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Objective: To establish and validate reference intervals of serum vitamin K for healthy children in China. Methods: A cross-sectional study was conducted from January 2020 to May 2023, involving 807 healthy children aged 0 to 14 years, selected by stratified random sampling based on the population distribution of children in eastern, central, western, and northeastern China. Sample collection was carried out in 16 hospitals across 12 provinces, autonomous regions, and municipalities. Basic information of the children was collected using a standardized self-design questionnaire. Serum levels of vitamin K 1 and vitamin K 2 (menaquinone-4 (MK-4), menaquinone-7 (MK-7)) were measured using liquid chromatography-tandem mass spectrometry. The reference intervals was established by direct approach. The children were divided into different groups by age. Inter-group comparisons were conducted using the Kruskal-Wallis non-parametric test, and the reference intervals ( P 2.5 - P 97.5 ) were determined using non-parametric methods. Screening 40 healthy children for small sample validation based on age groups within the reference range(25 from eastern, 10 from central, and 5 from western regions). Results: The age of the 807 children was 5.00 (2.00, 9.81) years, and 495 (61.3%) were males and 312 (38.7%) females. Reference intervals were established for 795 children, of whom 303 children were aged 1 month to 3 years and 492 were aged 4 to 14 years. The reference intervals for serum vitamin K 1 were 0.09-4.54 μg/L for children aged 1 month to 3 years, and 0.10-1.73 μg/L for 4-14 years. For MK-7, the intervals were 0.07-1.42 μg/L for 1 month to 3 years and 0.19-2.03 μg/L for 4-14 years. The reference intervals for MK-4 in children aged 1 month to 14 years were 0-0.42 μg/L. The measured values of serum vitamin K 1 , MK-4, and MK-7 in the validation samples did not exceed the reference limit in more than 2 samples. Conclusion: Reference intervals for vitamin K 1 , MK-4, and MK-7 in healthy children aged 1 month to 14 years have been established and validated, and can be used to assess vitamin K nutritional status in children.

Three Gram-stain-negative, aerobic, non-motile, chemoheterotrophic, short-rod-shaped bacteria, designated CDY1-MB1 T , CDY2-MB3, and BDY3-MB2, were isolated from three marine sediment samples collected in the eastern Pacific Ocean. Phylogenetic analysis based on 16S rRNA gene sequences indicated that these strains were related to the genus Aequorivita and close to the type strain of Aequorivita vitellina F4716 T (with similarities of 98.0-98.1%). Strain CDY1-MB1 T can grow at 15-37 °C (optimum 30 °C) and in media with pH 6-9 (optimum, pH 7), and tolerate up to 10% (w/v) NaCl. The predominant cellular fatty acids of strain CDY1-MB1 T were iso-C 15 : 0 (20.7%) and iso-C 17 : 0 3-OH (12.8%); the sole respiratory quinone was menaquinone 6; the major polar lipids were phosphatidylethanolamine, two unidentified aminolipids and two unidentified polar lipids. The digital DNA-DNA hybridization/average nucleotide identity values between strains CDY1-MB1 T , CDY2-MB3, and BDY3-MB2 and A. vitellina F4716 T were 24.7%/81.6-81.7%, thereby indicating that strain CDY1-MB1 T should represent a novel species of the genus Aequorivita . The genomic DNA G+C contents were 37.6 % in all three strains. Genomic analysis showed the presence of genes related to nitrogen and sulphur cycling, as well as metal reduction. The genetic traits of these strains indicate their possible roles in nutrient cycling and detoxification processes, potentially shaping the deep-sea ecosystem's health and resilience. Based upon the consensus of phenotypic and genotypic analyses, strain CDY1-MB1 T should be classified as a novel species of the genus Aequorivita , for which the name Aequorivita flava sp. nov. is proposed. The type strain is CDY1-MB1 T (=MCCC 1A16935 T =KCTC 102223 T ).

A Gram-stain-positive, aerobic, white-coloured, rod-shaped bacteria, designated as a strain dW9 T , was isolated from soil. Strain dW9 T was catalase-positive and oxidase-negative. Strain dW9 T grew at temperature of 20-37°C and at pH of 5.0-7.0. Phylogenetic and 16S rRNA gene analysis indicated that strain dW9 T belonged to the genus Paenibacillus with its closest relative being Paenibacillus filicis S4 T (97.4% sequence similarity). The genome size of dW9 T was 7,787,916 bp with DNA G+C content of 51.3%. The digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) values of dW9 T with its closest relatives were found to be <22.0% and <74.0%, respectively. The only respiratory quinone was MK-7, and the major fatty acids were antiso-C 15:0 and iso-C 16:0 . Overall, the comprehensive taxonomic analysis revealed that strain dW9 T met all the fundamental criteria to be classified as a novel species within the genus Paenibacillus. Accordingly, we propose the name Paenibacillus gyeongsangnamensis sp. nov., with the type strain dW9 T (=KCTC 43431 T =NBRC 116022 T ).

Strain SYSU D00308 T , a short-rod-shaped bacterium, was isolated from a sandy soil collected from the Gurbantunggut Desert, Xinjiang, PR China. Strain SYSU D00308 T was Gram-stain-negative, aerobic, pink-pigmented, non-motile, catalase- and oxidase-positive. The strain grew at 4-37 ℃, pH 5.0-8.0 and 0-1.5% (w/v) NaCl. 16S rRNA gene sequencing analyses demonstrated that strain SYSU D00308 T belonged to the genus Rufibacter and exhibited the highest sequence similarity (97.4%) to Rufibacter glacialis MDT1-10-3 T . Summed features 3, 4, and iso-C 15:0 were the major fatty acids, and menaquinone 7 (MK-7) was the sole respiratory menaquinone. The polar lipid profiles comprised phosphatidylethanolamine, an unidentified glycolipid, an unidentified phospholipid, two unidentified aminophospholipids, and two unidentified lipids. The genome size and DNA G + C content of strain SYSU D00308 T were 5,176,683 bp and 54.8%, respectively. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between SYSU D00308 T and members of the genus Rufibacter were 77.7-81.8% and 20.4-23.4% respectively, which were less than the corresponding thresholds (ANI: 95-96%; dDDH: 70%) for prokaryotic species definition. According to the genotypic, phenotypic and phylogenetic characteristics, strain SYSU D00308 T represents a novel species of the genus Rufibacter. We propose the name, Rufibacter psychrotolerans sp. nov., with SYSU D00308 T (= CGMCC 1.18621 T = KCTC 82275 T = MCCC 1K04970 T ) as the type strain., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Three novel mycelium-forming actinobacteria, designated OC33-EN06 T , OC33-EN07 T , and OC33-EN08 T , were isolated from wild orchid ( Aerides multiflora Roxb), collected from a hill evergreen forest in Northern Thailand. Strains OC33-EN06 T and OC33-EN07 T showed the highest 16S rRNA gene similarity with Actinomycetospora lutea TT00-04 T , 99.17 and 99.45%, respectively. Strain OC33-EN08 T showed high similarity with four species, namely ' Actinomycetospora termitidis Odt1-22 T ' (99.37%), Actinomycetospora chiangmaiensis DSM 45062 T (99.02%), Actinomycetospora corticicola 014-5 T (99.02%), and Actinomycetospora soli SF1 T (98.81%). Comparative genome analysis of OC33-EN06 T , OC33-EN07 T , and OC33-EN08 T with the closely related type strains showed that average nucleotide identity (ANI) based on blast, ANI based on MUMmer, and average amino acid identity values were less than 95% and the digital DNA-DNA hybridization values were less than 70%, all below the thresholds for species demarcation. The digital G+C content of OC33-EN06 T , OC33-EN07 T , and OC33-EN08 T were 74.5, 74, and 74 mol%, respectively. These three strains developed bud-like chains of non-motile cylindrical spores with a smooth surface. The cell-wall peptidoglycan contained meso -diaminopimelic acid. The whole-cell sugars contained ribose, arabinose, and galactose. The predominant menaquinone was MK-8(H 4 ). The phospholipid profile included phosphatidylcholine, phosphatidylethanolamine, phosphatidylmethylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, and phosphatidylinositol. Based on comparative analysis of genotypic, phenotypic and chemotaxonomic data, strains OC33-EN06 T (=TBRC 18349 T =NBRC 116543 T ), OC33-EN07 T (=TBRC 18350 T =NBRC 116544 T ), and OC33-EN08 T (=TBRC 18318 T =NBRC 116542 T ) represent the type strains of three novel species of the genus Actinomycetospora for which the names Actinomycetospora aeridis sp. nov., Actinomycetospora flava sp. nov., and Actinomycetospora aurantiaca sp. nov., are proposed.

Two novel bacteria, MJ-SS3 T and MJ-SS4, were isolated from tidal flat sediment sampled in Gochang, Republic of Korea. The isolates were Gram-stain-negative, aerobic, non-motile, rod-shaped, yellow-coloured, oxidase-positive, and catalase-positive. Strains MJ-SS3 T and MJ-SS4 grew at 20-37 °C (optimum, 30 °C), at pH 6-8 (optimum, pH 7.0) and in the presence of 0-7 % (w/v) NaCl (optimum, 2.0 % NaCl). Strains MJ-SS3 T and MJ-SS4 showed 99.9 % 16S rRNA gene sequence similarity. Phylogenetic analysis based on genome and 16S rRNA gene sequences indicated that strains MJ-SS3 T and MJ-SS4 were affiliated with the family Flavobacteriaceae and most closely related to Formosa maritima 1494 T (95.3 %), Hanstruepera flava NBU2984 T (95.2 %), Yeosuana marina JLT21 T (95.2 %), Meridianimaribacter flavus NH57N T (95.1 %), and Geojedonia litorea YCS-16 T (95.1 %). The major respiratory quinone was menaquinone-6. The major identified polar lipids were phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, and amino lipids. The major cellular fatty acids of strain MJ-SS3 T were iso-C 15 : 1 G (24.6 %), iso-C 15 : 0 (21.6 %), and iso-C 17 : 0 3-OH (15.8 %). The genome length of strain MJ-SS3 T is 3.1 Mbp (DNA G+C content, 32.5 mol%) and it has 2822 coding and 59 tRNA genes. The average amino acid identity and average nucleotide identity values, as well as biochemical, phylogenetic, and physiological characteristics, strongly supported the genotypic and phenotypic differentiation of strains MJ-SS3 T and MJ-SS4 from other members of the family Flavobacteriaceae . Hence, strains MJ-SS3 T and MJ-SS4 are considered to represent a novel species of a new genus in the family Flavobacteriaceae , for which the Gilvirhabdus luticola gen. nov., sp. nov. is proposed. The type strain is MJ-SS3 T (=KCTC 102114 T =KEMB 20189 T =JCM 36595 T ), with reference strain MJ-SS4 (=KCTC 102115=KEMB 20190).

Two Gram-stain-negative, aerobic, rod-shaped, orange-coloured bacterial strains, designated strain C216 T and strain M2295, were isolated from mature mushroom compost from composting facilities in Victoria and South Australia, Australia, respectively. External structures such as flagella or pili were not observed on the cells under scanning electron microscopy. Optimal growth was found to occur at 45 °C, at pH 7.25 and in the absence of NaCl on Emerson's 350 YpSs medium. The genome sequence of strain C216 T was 3 342 126 bp long with a G+C content of 40.5 mol%. Functional analysis of the genome of strain C216 T revealed genes encoding chitinolytic and hemi-cellulolytic functions, with 166 predicted genes associated with carbohydrate metabolism (8.9% of the predicted genes). These functions are important for survival in the mushroom compost environment, which is rich in hemicelluloses. No antibiotic resistance genes were found in the genome sequence. The major fatty acids of strain C216 T were iso-C 15 : 0 (56.7%), iso-C 17 : 0 3-OH (15.6%), C 16 : 1  ω 7 c /iso-C 15 : 0 2-OH (7.3%) and iso-C 15 : 1 G (6.1%). The only respiratory quinone was MK-7. The major polar lipid of strain C216 T was phosphatidylethanolamine, but three unidentified phospholipids, four unidentified aminophospholipids/aminolipids and one unidentified glycolipid were also detected. Phylogenetic analysis based on proteins encoded by the core genome (bac120, 120 conserved bacterial genes) showed that strain C216 T forms a distinct lineage in the family Chitinophagaceae and that the closest identified relative is Niabella soli (69.69% ANI). These data demonstrate that strain C216 T represents a novel genus and novel species within the family Chitinophagaceae , for which we propose the name Mycovorax composti . The type strain is C216 T (=DSM 114558 T =LMG 32998 T ).

Two new strains JP48 T and JP55 affiliated with the acidobacterial class Terriglobia have been isolated from fen soil sampled in the Fichtelgebirge Mountains near Bayreuth, Germany. Both strains were Gram-stain-negative, non-motile, non-spore-forming rods that divide by binary fission, segregate exopolysaccharide-like material and form capsules. Strains JP48 T and JP55 grew at 4-36 °C (optimum at 27 °C), pH 3.6-7.3 (optimum at pH 4.6-5.5) and with NaCl concentrations of 0-3% (optimum at 1.0%; w/v). Strains JP48 T and JP55 grew aerobically on a wide range of organic substrates including mono- and oligosaccharides, amino acids and short-chained fatty acids. MK-8 was identified as the major respiratory quinone. The major fatty acids for strains JP48 T and JP55 were iso -C 15 : 0 , C 16 : 1  ω7c, C 16 : 0 and iso -diabolic acid. Phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, lysophophatidylethanolamine, phosphatidylcholine, unidentified glyco- and glycophospholipids, and unidentified high mass lipid species were the major polar membrane lipids. The G+C content of strains JP48 T and JP55 was 57.4 and 57.2 mol%, respectively. The genomes of strains JP48 T and JP55 contained nine potential secondary metabolite regions encoding for the compound classes NRPS(-like), T3PKS, terpene, or lanthipeptide class IV. Phylogenetic reconstruction and 16S rRNA gene sequence similarities of 98.3 and 96.9% identified Edaphobacter dinghuensis DHF9 T and Edaphobacter lichenicola DSM 104462 T as the most closely related type strains to strains JP48 T and JP55. Based on their phenotype, phylogeny and chemotaxonomy, we propose the novel species Edaphobacter paludis sp. nov. (type strain JP48 T =DSM 109919 T =CECT 30269 T ; additional strain JP55=DSM 109920=CECT 30268) within the class Terriglobia of the phylum Acidobacteriota .

The genus Segeticoccus includes only one species with validly published name, Segeticoccus rhizosphaerae . The type strain Segeticoccus rhizosphaerae YJ01 T was isolated from soil in Korea, while Ornithinicoccus soli XNB-1 T was isolated from soil in China. Both strains share similar phenotypic and chemotaxonomic characteristics, including predominant menaquinone MK-8(H 4 ) and major polar lipids diphosphatidylglycerol and phosphatidylglycerol. Whole genome sequences revealed a DNA G+C content of 70.1 mol% for both strains and 100% similarity in their 16S rRNA gene sequences. Phylogenetic analysis showed they form a distinct cluster separate from other genera. Genomic comparisons showed average nucleotide identity and digital DNA-DNA hybridization values of 99.16 and 94.2%, respectively, indicating they represent a single species. Based on this genomic evidence, Ornithinicoccus soli Jiang et al . 2020 is proposed to be a later heterotypic synonym of Segeticoccus rhizosphaerae Lee and Whang 2020.

Four strains, designated dk4302 T , dk4209, xlx-73 T , and xlx-183, were isolated from Tibetan gazelle and red swamp crawfish collected from the Qinghai-Tibet Plateau and Jiangxi Province, PR China. The strains were Gram-stain-negative, aerobic, rod-shaped, non-motile, mucoid, and yellow-pigmented. Strains dk4302 T and dk4209 grew at 10-40 °C and pH 6.0-9.0, while strains xlx-73 T /xlx-183 grew at 15-40 °C and pH 6.0-10.0. Both strains exhibited growth in the presence of up to 3.5 % (w/v) NaCl. Phylogenetic and phylogenomic analyses based on the 16S rRNA gene sequences and 652 core genes, respectively, revealed that the four strains formed two distinct clusters in the genus Sphingobacterium . Strains dk4302 T and dk4209 formed a distinct clade with Sphingobacterium hotanense XH4 T and Sphingobacterium humi D1 T . The most closely related strains to xlx-73 T and xlx-183 were Sphingobacterium nematocida M-SX103 T . The DNA G+C contents were 38.9 and 39.8 mol%. The digital DNA-DNA hybridization (dDDH) values between dk4302 T and S. humi D1 T and S. hotanense XH4 T were 19.2 and 21.8 % (19.0 and 21.6 % for strain dk4209), respectively. The corresponding average nucleotide identity (ANI) values were 74.3 and 78.1 % (74.4 and 78.3 % for strain dk4209), respectively. The dDDH values between xlx-73 T (xlx-183) and S. nematocida M-SX103 T was 24.6 % (25.7 %). The corresponding ANI value was 85.7 % (85.5 % for strain xlx-183). The major fatty acid and respiratory quinone of dk4302 T and xlx-73 T were iso-C 15:0 and MK7. The polar lipids identified in all of the novel strains were phosphatidylethanolamine, phosphoglycolipids, aminophospholipids, and phospholipids. A total of 61/190 (32.1 %) and 82/190 (43.2 %) carbon substrates were metabolized by strains dk4302 T and xlx-73 T in the Biolog MicroPlates, respectively. Based on the results from this polyphasic taxonomic study, two novel species in the genus Sphingobacteruim are proposed, namely Sphingobacteruim zhuxiongii sp. nov. (type strain dk4302 T =CGMCC 1.16795 T =JCM 33600 T ) and Sphingobacteruimluzhongxinii sp. nov. (type strain xlx-73 T =GDMCC 1.1712 T =JCM 33886 T ).

A novel, Gram-positive, facultatively anaerobic, and non-motile bacterial strain, designated B2T-5 T , was isolated from jeotgal, a traditional Korean fermented seafood. Colonies grown on gifu anaerobic medium agar plates were cream-coloured, irregular, and umbonate with curled margins. Optimal growth of strain B2T-5 T occurred at 20 °C, pH 8.0, and in the presence of 1% (w/v) NaCl. Strain B2T-5 T was negative for oxidase and catalase activity. Hippurate was not hydrolysed and acetoin was not produced. The major cellular fatty acids were C 18 : 1  ω 9 c and C 16 : 0 . The cell-wall peptidoglycan was of the A4 α type containing l-Lys-d-Asp. The predominant respiratory quinone was menaquinone 7. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylcholine. According to the phylogenetic analysis based on 16S rRNA gene sequences, strain B2T-5 T was most closely related to Vagococcus teuberi DSM 21459 T , showing 98.2% sequence similarity. Genome sequencing of strain B2T-5 T revealed a genome size of 2.0 Mbp and a G+C content of 33.8 mol%. The average nucleotide identities of strain B2T-5 T with Vagococcus teuberi DSM 21459 T , Vagococcus bubulae SS1994 T , and Vagococcus martis D7T301 T were 75.0, 74.7, and 75.1%, respectively. Based on the phenotypic, chemotaxonomic, and genotypic data, strain B2T-5 T represents a novel species of the genus Vagococcus , for which the name Vagococcus jeotgali sp. nov. is proposed. The type strain is B2T-5 T (=KCTC 21223 T =JCM 35937 T ).

The K family of vitamins includes a collection of molecules with different pharmacokinetic characteristics. Menaquinone-7 (MK-7) has the finest properties and is the most therapeutically beneficial due to its long plasma half-life and outstanding extrahepatic bioavailability. MK-7 exhibits cis-trans isomerism, and merely the all-trans form is biologically efficacious. Therefore, the remedial value of MK-7 end products is exclusively governed by the quantity of all-trans MK-7. Consumers favour fermentation for the production of MK-7; however, it involves several challenges. The low MK-7 yield and extensive downstream processing requirements increase production costs, resulting in an expensive final product that is not universally available. Bacterial cell immobilisation with iron oxide nanoparticles (IONs) can potentially address the limitations of MK-7 fermentation. Uncoated IONs tend to have low stability and can adversely affect cell viability; thus, amine-functionalised IONs, owing to their increased physicochemical stability and biocompatibility, are a favourable alternative. Nonetheless, employing biocompatible IONs for this purpose is only advantageous if the bioactive MK-7 isomer is obtained in the most significant fraction, exploring which formed the aim of this investigation. Two amine-functionalised IONs, namely 3-aminopropyltriethoxysilane (APTES)-coated IONs (IONs@APTES) and L-Lysine (L-Lys)-coated IONs (L-Lys@IONs), were synthesised and characterised, and their impact on various parameters was evaluated. IONs@APTES were superior, and the optimal concentration (300 μ g/mL) increased all-trans MK-7 production and improved its yield relative to the untreated cells by 2.3- and 3.1-fold, respectively. The outcomes of this study present an opportunity to develop an innovative and effective fermentation method that enhances the production of bioactive MK-7., (© 2023. The Author(s).)

Promising outcomes have been reported in elder patients with acute myeloid leukemia (AML) using combined therapy of venetoclax (VEN) and azacytidine (AZA) in recent years. However, approximately one-third of patients appear to be refractory to this therapy. Vitamin K2 (VK2) shows apoptosis-inducing activity in AML cells, and daily oral VK2 (menaquinone-4, GlakayR) has been approved for patients with osteoporosis in Japan. We observed a high response rate to AZA plus VEN therapy, with no 8-week mortality in the newly diagnosed AML patients consuming daily VK2 in our hospital. The median age of the patients was 75.9 years (range 66-84) with high-risk features. Patients received AZA 75 mg/m2 on D1-7, VEN 400 mg on D1-28, and daily VK2 45 mg. The CR/CRi ratio was 94.7% (18/19), with a CR rate of 79%. Complete cytogenetic CR was achieved in 15 of 19 (79%) patients, and MRD negativity in 2 of 15 (13%) evaluable CR patients. Owing to the extremely high response rate in clinical settings, we further attempted to investigate the underlying mechanisms. The combination of VK2 and VEN synergistically induced apoptosis in all five AML cell lines tested. VK2, but not VEN, induced mitochondrial reactive oxygen species (ROS), leading to the transcriptional upregulation of NOXA, followed by MCL-1 repression. ROS scavengers repressed VK2 induced-NOXA expression and led to the cancellation of pronounced apoptosis and the downregulation of MCL-1 by VK2 plus VEN. Additionally, knockdown and knockout of NOXA resulted in abrogation of the MCL-1 repression as well as enhanced cytotoxicity by the two-drug combination, indicating that VK2 suppresses MCL-1 via ROS-mediated NOXA induction. These data suggest that the dual inhibition of BCL-2 by VEN and MCL-1 by VK2 is responsible for the remarkable clinical outcomes in our patients. Therefore, large-scale clinical trials are required., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Tauchi et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

A Gram-stain-positive, rod-shaped, non-spore-forming and non-motile bacterium, designated strain WY-16 T . Growth was observed at 20-42 °C (optimum, 30 °C), pH 6-9 (optimum, pH 7) and salinity of 0-3 % (w/v; optimum, 1 %). Phylogenetic analysis based on genome sequences indicated that WY-16 T was affiliated to the family Microbacteriaceae and most closely related to Salinibacterium xinjiangense and Salinibacterium amurskyense . The average nucleotide identity values between strain WY-16 T and S. xinjiangense and S. amurskyense were 74.7 and 72.5 %, respectively. The digital DNA-DNA hybridization values between strain WY-16 T and S. xinjiangense and S. amurskyense were 19.6 and 18.6 %, respectively. The predominant fatty acids were anteiso-C 15 : 0 , iso-C 16 : 0 and iso-C 16 : 0 10-methyl. The major menaquinones were MK-12, MK-13, MK-14 and MK-15. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, one unidentified glycolipid and one unidentified phospholipid. The cell-wall peptidoglycan contained 2,4-diaminobutyric acid as the diamino acid and ribose, rhamnose, glucose and galactose were the major cell-wall sugars. Based on phenotypic, genotypic and phylogenetic evidence, strain WY-16 T represents a novel species in the genus Salinibacterium , for which the name Salinibacterium soli sp. nov. is proposed. The type strain is WY-16 T (=GDMCC 1.4011 T =JCM 36421 T ).

Strain T-12 T , an orange, Gram-stain-negative, non-motile, rod-shaped strain, was isolated in November 2013 from water samples collected from an Atlantic salmon ( Salmo salar ) fry culturing system at a fish farm in Chile. Phylogenetic analysis based on 16S rRNA sequences (1394 bp) revealed that strain T-12 T belonged to the genus Flavobacterium , showing close relationships to Flavobacterium bernardetii F-372 T (99.48 %) and Flavobacterium terrigena DS-20 T (98.50 %). The genome size of strain T-12 T was 3.28 Mb, with a G+C content of 31.1 mol%. Genome comparisons aligned strain T-12 T with Flavobacterium bernardetii F-372 T (GCA&#95;011305415) and Flavobacterium terrigena DSM 17934 T (GCA&#95;900108955). The highest digital DNA-DNA hybridization (dDDH) values were 42.6 % with F. bernardetii F-372 T (GCA&#95;011305415) and 33.9 % with F. terrigena DSM 17934 T (GCA&#95;900108955). Pairwise average nucleotide identity (ANI) calculations were below the species cutoff, with the best results with F. bernardetii F-372 T being: ANIb, 90.33 %; ANIm, 91.85 %; and TETRA, 0.997 %. These dDDH and ANI results confirm that strain T-12 T represents a new species. The major fatty acids were iso-C 15 : 0 and C 15 : 1 ω6 с . Detected polar lipids included phospholipids ( n =2), aminophospholipid ( n =1), aminolipid ( n =1) and unidentified lipids ( n =2). The predominant respiratory quinone was menaquinone MK7 (80 %) followed by MK-6 (20 %). Phenotypic, chemotaxonomic, and genomic data support the classification of strain T-12 T (=CECT 30410 T =RGM 3222 T ) as representing a novel species of Flavobacterium , for which the name Flavobacterium facile sp. nov. is proposed.

An orange-pigmented, Gram-stain-negative, strictly aerobic, non-flagellated and rod-shaped bacterium, designated strain DF17 T , was isolated from coastal sediment collected from Jingzi Wharf, Weihai, PR China. The optimal growth conditions were determined to be at 30 °C, pH 7.5, and in 3 % (w/v) NaCl. According to phylogenetic analysis of the 16S rRNA gene sequence, strain DF17 T showed the highest sequence similarity of 96.9 % to Winogradskyella aquimaris KCTC 23502 T . The DNA G+C content was 35.8 mol%, and the major fatty acids were iso-C 15 : 1 G, iso-C 15 : 0 , and iso-C 17 : 0 3-OH. The major polar lipids were two aminoglycolipids, one phosphatidylethanolamine and four unidentified lipids. The predominant respiratory quinone was menaquinone-6 (MK-6). The average nucleotide identity, digital DNA-DNA hybridization, and amino acid identity values between strain DF17 T and other Winogradskyella species were below the species delineation thresholds of 69.35-72.95 %, 16.9-19.6 % and 71.25-78.93 %, respectively. On the basis of its phenotypic, genetic and physiological characteristics, strain DF17 T is suggested to represent a novel species of the genus Winogradskyella , for which the name Winogradskyella pelagia sp. nov. is proposed. The type strain is DF17 T (MCCC 1H00456 T =KCTC 82421 T ).

Two strains, designated as SYSU M80004 T and SYSU M80005 T , were isolated from water sampled in the Pearl River Estuary, Guangzhou, Guangdong, PR China. The strains were Gram-stain-negative and aerobic. Strain SYSU M80004 T could grow at pH 6.0-8.0 (optimum, pH 7.0), 22-30 °C (optimum, 28 °C) and in the presence of 0-1 % NaCl (w/v; optimum 0 %). Strain SYSU M80005 T could grow at pH 6.0-8.0 (optimum, pH 7.0), 4-37 °C (optimum, 28 °C) and in the presence of 0-1 % NaCl (w/v; optimum 0%). Both strains contained MK-6 as the predominant menaquinone. C 16 : 0 and iso-C 15 : 0 were identified as the major fatty acids (>10 %) of strain SYSU M80004 T while strain SYSU M80005 T contained iso-C 15 : 0 and iso-C 17 : 0 3-OH as major fatty acids. Phosphatidylethanolamine was present as the major polar lipid in both strains. The average nucleotide identity and digital DNA-DNA hybridization values between these two strains and their closest relatives were 73.5-79.3 % and 19.6-23.2 %, respectively. Phylogenetic analysis based on the 16S rRNA gene and genomic sequences indicated they belonged to the genus Flavobacterium . Therefore, on the basis of phenotypic, physiological, chemotaxonomic and genomic evidence, two novel species, Flavobacterium adhaerens sp. nov. (type strain=SYSU M80004 T =CDMCC 1.4522 T =KCTC 102268 T ) and Flavobacterium maritimum sp. nov. (type strain=SYSU M80005 T =CGMCC 1.4523 T = KCTC 102269 T ) are proposed.

Six novel bacterial strains, designated N016 T , N017, N022 T , N028, N056 T , and N064, were isolated from soil sampled on the Qinghai-Tibet Plateau. Cells were aerobic, orange or yellow, globular or rod-shaped, non-motile, non-spore-forming, Gram-stain-positive, catalase-positive and oxidase-negative. All the isolates were salt-tolerant and could grow in the range of 4-42 °C. Results of phylogenomic analyses based on 16S rRNA gene sequences and core genomic genes showed that the three pairs of strains (N016 T /N017, N022 T /N028, and N056 T /N064) were closely related to the members of the genus Planococcus , and clustered with Planococcus ruber , Planococcus glaciei , and Planococcus chinensis . The digital DNA-DNA hybridization and average nucleotide identity values of the six novel strains with other members of the genus Planococcus were within the ranges of 18.7-53 % and 70.58-93.49 %, respectively, all below the respective recommended thresholds of 70.0 % and 95-96 %. The genomic DNA G+C content of the six strains ranged from 43.5 to 46.0 mol%. The major fatty acids of the six strains were anteiso -C 15 : 0 , iso -C 14 : 0 , and C 16 : 1  ω 7 c alcohol. The predominant polar lipids of strains N016 T , N022 T , and N056 T were diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine. Menaquinones 7 and 8 were the respiratory quinones. The results of the above analyses indicated that the six strains represent three novel species of the genus Planococcus , for which the names Planococcus shenhongbingii sp. nov. (type strain N016 T =GDMCC 1.4062 T =JCM 36224 T ), Planococcus shixiaomingii sp. nov. (type strain N022 T =GDMCC 1.4063 T =JCM 36225 T ), and Planococcus liqunii sp. nov. (type strain N056 T =GDMCC 1.4064 T =JCM 36226 T ) are proposed.

A bacterial strain designated PU5-4 T was isolated from the mealworm (the larvae of Tenebrio molitor ) intestines. It was identified to be Gram-stain-negative, strictly aerobic, rod-shaped, non-motile, and non-spore-forming. Strain PU5-4 T was observed to grow at 10-40 °C, at pH 7.0-10.0, and in the presence of 0-3.0 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain PU5-4 T should be assigned to the genus Sphingobacterium . The 16S rRNA gene sequence similarity analysis showed that strain PU5-4 T was closely related to the type strains of Sphingobacterium lactis DSM 22361 T (98.49 %), Sphingobacterium endophyticum NYYP31 T (98.11 %), Sphingobacterium soli NCCP 698 T (97.69 %) and Sphingobacterium olei HAL-9 T (95.73 %). The predominant isoprenoid quinone is MK-7. The major fatty acids were identified as iso-C 15 : 0 , iso-C 17 : 0 3-OH and summed feature 3 (C 16 : 1  ω 7 c and/or C 16 : 1  ω 6 c ) and summed feature 9 (iso-C 17 : 0  ω 9 c ). The polar lipids are phosphatidylethanolamine, one unidentified phospholipid, and six unidentified lipids. The genomic DNA G+C content of strain PU5-4 T is 40.24 mol%. The average nucleotide identity of strain PU5-4 T exhibited respective values of 73.88, 73.37, 73.36 and 70.84 % comparing to the type strains of S. lactis DSM 22361 T , S. soli NCCP 698 T , S. endophyticum NYYP31 T and S. olei HAL-9 T , which are below the cut-off level (95-96 %) for species delineation. Based on the above results, strain PU5-4 T represents a novel species of the genus Sphingobacterium , for which the name Sphingobacterium temoinsis sp. nov. is proposed. The type strain is PU5-4 T (=CGMCC 1.61908 T =JCM 36663 T ).

Strain ELA7 T , a novel Gram-negative, non-motile bacterium with a white pigment and rod-shaped morphology, was isolated from the faeces of an eland at Seoul Grand Park, a zoo in the Republic of Korea. The novel bacterial strain grew optimally in R2A medium under the following conditions: 0 % (w/v) NaCl, pH 8.0, and 34 °C. Based on phylogenetic analyses using 16S rRNA gene sequencing, strain ELA7 T was found to have the closest relatedness to Pedobacter ginsengisoli Gsoil 104 T (97.8 %), P. frigoris RP-3-15 T (97.2 %), P. humi THG S15-2 T (97.0 %), P. seoulensis THG-G12 T (97.0 %), and P. foliorum LMG 31463 T (96.9 %). The genome size and genomic DNA G+C content of strain ELA7 T were 3.63 Mbp and 46.5 %, respectively. A whole genome-level comparison of strain ELA7 T with P. ginsengisoli Gsoil 104 T , P. frigoris RP-3-15 T , P. africanus DSM 12126 T , and P. psychroterrae RP-1-14 T revealed average nucleotide identity values of 72.0, 71.8, 71.9, and 71.6 %, respectively. The major fatty acids were summed feature 3 (comprising C 16 : 1  ω7 c and/or C 16 : 1  ω6 c ) and MK-7 was the predominant respiratory quinone. The major polar lipids of strain ELA7 T were phosphatidylethanolamine, sphingolipid, unidentified aminolipid, unidentified phosphoglycolipid, unidentified glycolipid, and eight unidentified lipids. Considering our chemotaxonomic, genotypic, and phenotypic findings, strain ELA7 T (=KACC 23137 T =JCM 36003 T ) is identified as representing a novel species within the genus Pedobacter , for which the name Pedobacter faecalis sp. nov. is proposed.

Gram-stain-positive, aerobic, rod-shaped strains, YJM1 T and YJM12S, were isolated from Maebong Mountain, Dogok-dong, Gangnam-gu, Seoul, Republic of Korea. Strains YJM1 T and YJM12S exhibited growth at 5-35 °C (optimum, 20-30 °C) and pH 6-9 (optimum, pH 7) and in 0-4 % (w/v) NaCl. Strains YJM1 T and YJM12S showed highest 16S rRNA gene sequence similarity to the following members of the genus Arthrobacter : A. nanjingensis A33 T (98.3 %/98.2 % similarity), A. woluwensis NBRC 107840 T (98.2 %/98.1 %), A. humicola KV-653 T (97.3 %), A. oryzae KV-651 T (97.3 %), and A. globiformis NBRC 12137 T (97.2 %). The strains grew well on Reasoner's 2A, nutrient, Mueller-Hinton, yeast-dextrose, and glucose-peptone-meat extract agars. The major polar lipids of strain YJM1 T were phosphatidylglycerol, diphosphatidylglycerol, and phosphatidylinositol. The primary respiratory quinone of strain YJM1 T was MK-9(H 2 ), and the major fatty acids of strains YJM1 T and YJM12S were anteiso-C 15 : 0 , anteiso-C 17 : 0 , iso-C 15 : 0 , and iso-C 16 : 0 . The DNA G+C content, based on the whole genome sequence of strain YJM1 T , was 68.3 mol%. Average nucleotide identity values and digital DNA-DNA hybridization values between strain YJM1 T and the reference strains ranged from 75.0 to 92.7 % and from 21.0 to 65.3 %, respectively. Strain YJM1 T exhibited antimicrobial activity against Bacillus subtilis and Escherichia coli . Considering the chemotaxonomic, phenotypic, genotypic, and phylogenetic results, we propose the strain YJM1 T represents a novel species in the genus Arthrobacter and suggest the name Arthrobacter horti sp. nov. (type strain YJM1 T =KACC 23300 T =JCM 36483 T ).

Two pink-pigmented bacteria, designated strains NEAU-140 T and NEAU-K T , were isolated from field soil collected from Linyi, Shandong Province, PR China. Both isolates were aerobic, Gram-stain-negative, rod-shaped, and facultatively methylotrophic. 16S rRNA gene sequences analysis showed that these two strains belong to the genus Methylobacterium . Strain NEAU-140 T exhibited high 16S rRNA gene sequence similarities to Methylobacterium radiotolerans NBRC 15690 T (97.43 %) and Methylobacterium phyllostachyos NBRC 105206 T (97.36 %). Strain NEAU-K T exhibited high 16S rRNA gene sequence similarities to M. phyllostachyos NBRC 105206 T (99.00 %) and Methylobacterium longum DSM 23933 T (98.72 %). A phylogenetic tree based on 16S rRNA gene sequences showed that strain NEAU-140 T formed a clade with Methylobacterium aerolatum (95.94 %), Methylobacterium persicinum (95.66 %) and Methylobacterium komagatae (96.87 %), and strain NEAU-K T formed a cluster with M. phyllostachyos and M. longum . The predominant fatty acid in both strains was C 18 : 1  ω 7 c . Both strains contained ubiquinone Q-10 as the only respiratory quinone. The polar lipid profiles of both strains contained diphosphatidylglycerol, phosphatidylethanolamine, and phosphatidylcholine. Whole-genome phylogeny showed that strains NEAU-140 T and NEAU-K T formed a phyletic line with M. aerolatum , M. persicinum , Methylobacterium radiotolerans , Methylobacterium fujisawaense , Methylobacterium oryzae , Methylobacterium tardum , M. longum and M. phyllostachyos . The orthologous average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain NEAU-140 T and its closely related strains were lower than 82.62 and 25.90  %, respectively. The ANI and dDDH values between strain NEAU-K T and its closely related strains were lower than 86.29 and 31.7 %, respectively. The genomic DNA G+C contents were 71.63 mol% for strain NEAU-140 T and 69.08 mol% for strain NEAU-K T . On the basis of their phenotypic and phylogenetic distinctiveness and the results of dDDH and ANI hybridization, these two isolates represent two novel species within the genus Methylobacterium , for which the names Methylobacterium amylolyticum sp. nov. (type strain NEAU-140 T =MCCC 1K08801 T =DSM 110568 T ) and Methylobacterium ligniniphilum sp. nov. (type strain NEAU-K T =MCCC 1K08800 T =DSM 110567 T ) are proposed.

Three actinobacterial strains, KSW2-21 T , KSW2-29 T and KSW4-17 T , were isolated from dried seaweeds collected around Gwakji Beach in Jeju, Republic of Korea. Their taxonomic positions were determined based on genomic, physiological and morphological characteristics. The isolates were Gram-positive, aerobic, non-motile, rod-shaped bacteria characterized by the following chemotaxonomic features: ornithine as the cell wall diamino acid, the N -glycolyl type of murein, MK-11 as the predominant menaquinone, polar lipids including diphosphatidylglycerol, phosphatidylglycerol, two unidentified glycolipids and four unidentified phospholipids, with anteiso-C 15 : 0 , iso-C 16 : 0 and anteiso-C 17 : 0 as the the major fatty acids. The 16S rRNA gene phylogeny showed that the novel strains formed three distinct sublines within the genus Microbacterium . Strain KSW4-17 T formed a tight cluster with the type strain of Microbacterium hydrothermale , while strains KSW2-21 T and KSW2-29 T occupied distinct positions between the type strains of M. hydrothermale and Microbacterium testaceum . Strains KSW4-17 T and KSW2-29 T showed 99.9 % rRNA gene sequence similarity to M. hydrothermale CGMCC 1.12512 T , while strain KSW2-21 T revealed 99.4 % 16S rRNA gene sequence similarity to the type strains of M. hydrothermale and M. testaceum . The genome sizes and genomic G+C contents of the three isolates ranged from 3.44 to 3.74 Mbp and from 70.3 to 70.8 mol%, respectively. The phylogenomic tree based on 92 core gene sequences exhibited similar topologies to the 16S rRNA gene phylogeny. The comparison of overall genomic relatedness indices, such as average nucleotide indentity and digital DNA-DNA hybridization, supported that the isolates represent three new species of the genus Microbacterium . Based on the results obtained here, Microbacterium algihabitans sp. nov. (type strain, KSW2-21 T =KACC 23322 T =DSM 116381 T ), Microbacterium phycohabitans sp. nov. (type strain KSW2-29 T =KACC 22350 T =NBRC 115221 T ) and Microbacterium galbum sp. nov. (type strain, KSW4-17 T =KACC 23323 T =DSM 116383 T ) are proposed.

A novel facultatively anaerobic and Gram-stain-negative bacterium, designated FJH33 T , was isolated from mangrove sediment sampled in Zhangzhou, PR China. Cells of strain FJH33 T were rod-shaped or slightly curved-shaped, with widths of 0.3-0.5 µm and lengths of 1.0-3.0 µm. Optimum growth of strain FJH33 T occurred in the presence of 3 % NaCl (w/v), at 33 °C and at pH 7.0. Oxidase activity was negative, while catalase activity was positive. Its iron-reducing ability was determined. Based on 16S rRNA gene sequence similarity, strain FJH33 T was most closely related to Maribellus luteus XSD2 T (95.1 %), followed by Maribellus sediminis Y2-1-60 T (95.0 %) and Maribellus maritimus 5E3 T (94.9 %). Genome analysis of strains FJH33 T and M. luteus XSD2 T revealed low genome relatedness, with an average nucleotide identity value of 73.8% and a digital DNA-DNA hybridization value of 19.0%. Phylogenetic trees built from 16S rRNA genes and genome sequences showed that strain FJH33 T represents a relatively independent phylogenetic lineage within the genus Maribellus . The major cellular fatty acids (≥10 %) were iso-C 15 : 0 and C 18 : 1  ω 9 c . The sole respiratory quinone was MK-7. The polar lipids consisted of phosphatidylethanolamine, diphosphatidylcholine, diphosphatidyglycerol and one unidentified lipid. The DNA G+C content was 41.4 mol%. Based on the integrated results of phylogenetic, physiological, biochemical and chemotaxonomic characterizations, we propose that strain FJH33 T represents a novel species of the genus Maribellus , for which the name Maribellus mangrovi sp. nov. is proposed. The type strain is FJH33 T (=KCTC 102210 T =MCCC 1H01459 T ).

An anaerobic, mesophilic, syntrophic, archaeon strain MK-D1 T , was isolated as a pure co-culture with Methanogenium sp. strain MK-MG from deep-sea methane seep sediment. This organism is, to our knowledge, the first cultured representative of 'Asgard' archaea, an archaeal group closely related to eukaryotes. Here, we describe the detailed physiology and phylogeny of MK-D1 T and propose Promethearchaeum syntrophicum gen. nov., sp. nov. to accommodate this strain. Cells were non-motile, small cocci, approximately 300-750 nm in diameter and produced membrane vesicles, chains of blebs and membrane-based protrusions. MK-D1 T grew at 4-30 °C with optimum growth at 20 °C. The strain grew chemoorganotrophically with amino acids, peptides and yeast extract with obligate dependence on syntrophy with H 2 -/formate-utilizing organisms. MK-D1 T showed the fastest growth and highest maximum cell yield when grown with yeast extract as the substrate: approximately 3 months to full growth, reaching up to 6.7×10 6 16S rRNA gene copies ml -1 . MK-D1 T had a circular 4.32 Mb chromosome with a DNA G+C content of 31.1 mol%. The results of phylogenetic analyses of the 16S rRNA gene and conserved marker proteins indicated that the strain is affiliated with 'Asgard' archaea and more specifically DHVC1/DSAG/MBG-B and 'Lokiarchaeota'/'Lokiarchaeia'. On the basis of the results of 16S rRNA gene sequence analysis, the most closely related isolated relatives were Infirmifilum lucidum 3507LT T (76.09 %) and Methanothermobacter tenebrarum RMAS T (77.45 %) and the closest relative in enrichment culture was Candidatus 'Lokiarchaeum ossiferum' (95.39 %). The type strain of the type species is MK-D1 T (JCM 39240 T and JAMSTEC no. 115508). We propose the associated family, order, class, phylum, and kingdom as Promethearchaeaceae fam. nov., Promethearchaeales ord. nov., Promethearchaeia class. nov., Promethearchaeota phyl. nov., and Promethearchaeati regn. nov., respectively. These are in accordance with ICNP Rules 8 and 22 for nomenclature, Rule 30(3)(b) for validation and maintenance of the type strain, and Rule 31a for description as a member of an unambiguous syntrophic association.

A Gram-stain-negative, yellow-pigmented, and facultatively aerobic bacterium, designated strain GPA1 T , was isolated from plastic waste landfill soil in the Republic of Korea. The cells were non-motile short rods exhibiting oxidase-negative and catalase-positive activities. Growth was observed at 15-40 °C (optimum, 30 °C), at pH 6.0-9.0 (optimum, pH 7.0-8.0) and in the presence of 0-2.5 % (w/v) NaCl (optimum, 0 %). Menaquinone-7 was the sole respiratory quinone, and iso-C 15 : 0 , C 16 : 1  ω 5 c , and iso-C 17 : 0 3-OH were the major cellular fatty acids (>10 % of the total fatty acids). Phosphatidylethanolamine was identified as a major polar lipid. Phylogenetic analyses based on 16S rRNA gene sequences and 120 concatenated marker protein sequences revealed that strain GPA1 T formed a distinct lineage within the genus Chitinophaga . The genome of strain GPA1 T was 6078 kb in size with 53.8 mol% G+C content. Strain GPA1 T exhibited the highest similarity to Chitinophaga rhizosphaerae T16R-86 T , with a 98.6 % 16S rRNA gene sequence similarity, but their average nucleotide identity and digital DNA-DNA hybridization values were 82.5 and 25.9 %, respectively. Based on its phenotypic, chemotaxonomic, and phylogenetic characteristics, strain GPA1 T represents a novel species of the genus Chitinophaga , for which the name Chitinophaga pollutisoli sp. nov. is proposed. The type strain is GPA1 T (=KACC 23415 T =JCM 36644 T ).

Menaquinone-7 (MK-7), a vital vitamin with numerous health benefits, is synthesized and secreted extracellularly by the formation of biofilm, dominantly in Bacillus strains. Our team developed an innovative biofilm reactor utilizing Bacillus subtilis natto cells to foster biofilm growth on plastic composite supports to produce MK-7. Continuous fermentation in biofilm reactors offers a promising strategy for achieving sustainable and efficient production of Menaquinone-7 (MK-7). Unlike conventional batch fermentation, continuous biofilm reactors maintain a steady state of operation, which reduces resource consumption and waste generation, contributing to sustainability. By optimizing fermentation conditions, MK-7 production was significantly enhanced in this study, demonstrating the potential for sustainable industrial-scale production. To determine the optimal operational parameters, various dilution rates were tested. These rates were selected based on their potential to enhance nutrient supply and biofilm stability, thereby improving MK-7 production. By carefully considering the fermentation conditions and systematically varying the dilution rates, MK-7 production was significantly enhanced during continuous fermentation. The MK-7 productivity was found to increase from 0.12 mg/L/h to 0.33 mg/L/h with a dilution rate increment from 0.007 to 0.042 h -1 ). This range was chosen to explore the impact of various nutrient supply rates on MK-7 production and to identify the optimal conditions for maximizing productivity. However, a further increase in the dilution rate to 0.084 h -1 led to reduced productivity at approximately 0.16 mg/L/h, likely due to insufficient retention time for effective biofilm formation. Consequently, a dilution rate of 0.042 h -1 exhibited the highest productivity of 0.33 mg/L/h, outperforming all investigated dilution rates and demonstrating the critical balance between nutrient supply and retention time in continuous fermentation. These findings validate the feasibility of operating continuous fermentation at a 0.084 h -1 dilution rate, corresponding to a 48 h retention time, to achieve the highest MK-7 productivity compared to conventional batch fermentation. The significant advancements achieved in enhancing Menaquinone-7 (MK-7) productivity through continuous fermentation at optimal dilution rates in the present work indicate promising prospects for even greater efficiency and sustainability in MK-7 production through future developments., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Menaquinone-4 (MK-4) is an isoform of vitamin K 2 that has been shown to exert various biological actions besides its functions in blood coagulation and bone metabolism. Here we examined the effect of MK-4 on a mouse model of intracerebral hemorrhage (ICH). Daily oral administration of 200 mg/kg MK-4 starting from 3 h after induction of ICH by intrastriatal collagenase injection significantly ameliorated neurological deficits. Unexpectedly, MK-4 produced no significant effects on various histopathological parameters, including the decrease of remaining neurons and the increase of infiltrating neutrophils within the hematoma, the increased accumulation of activated microglia/macrophages and astrocytes around the hematoma, as well as the injury volume and brain swelling by hematoma formation. In addition, ICH-induced increases in nitrosative/oxidative stress reflected by changes in the immunoreactivities against nitrotyrosine and heme oxygenase-1 as well as the contents of malondialdehyde and glutathione were not significantly affected by MK-4. In contrast, MK-4 alleviated axon tract injury in the internal capsule as revealed by neurofilament-H immunofluorescence. Enhanced preservation of the corticospinal tract by MK-4 was also confirmed by retrograde labeling of neurons in the primary motor cortex innervating the spinal cord. These results suggest that MK-4 produces therapeutic effect on ICH by protecting structural integrity of the corticospinal tract., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background and Aims: Experimental studies suggested that vitamin K supplementation may retard arterial calcification. Recently, serum calcification propensity time (T 50 ) has been suggested as a functional biomarker for arterial wall calcification propensity. In this post-hoc analysis of a clinical trial, we evaluated the effect of six-month oral vitamin K supplementation on T 50 and assessed the correlation between T 50 and imaging arterial calcification parameters in people with type 2 diabetes (T2DM)., Methods: This double-blind, randomized, placebo-controlled trial included 68 participants (age = 69 ± 8 years, 76% male) with T2DM. Participants were assigned to menaquinone-7 (360 μg/day; n = 35) or placebo (n = 33). T 50 was measured via nephelometry in serum collected at baseline, three and six months. Arterial calcification was measured at baseline and six months via 18 F-Na PET-CT and conventional CT using Target-to-Background ratio (TBR) and Agatston score. Longitudinal analysis of covariance adjusted for baseline T 50 was used to study the treatment effect. Spearman's correlation was used to assess the correlation between T 50 and imaging calcification parameters., Results: Median baseline T 50 was similar in the vitamin K (350 [321-394] minutes) and placebo groups (363 [320-398]). There was no significant difference in T 50 between treatment arms over time (ẞ = 1.00, 95%C.I. = 0.94-1.07, p = 0.982). The correlation coefficient of T 50 with TBR and Agatston score at baseline were -0.185 (p = 0.156) and -0.121 (p = 0.358), respectively., Conclusions: No effect of vitamin K supplementation on T 50 was observed in T2DM. Moreover, T 50 did not correlate with TBR and Agatston score. Further research on vitamin K in arterial calcification and on the validity of T 50 as arterial calcification marker is warranted., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Objective: Patients on dialysis treatment have poor functional vitamin K status, and this may increase the risk of vascular calcification. Vitamin K supplementation may therefore be relevant in patients on dialysis, but the procoagulant effects have not been studied. We evaluated effects of menaquinone-7 (MK-7) supplementation on biomarkers of coagulation in patients on dialysis., Methods: Double-blinded, placebo-controlled study in 123 patients on dialysis randomized to 52 weeks of vitamin K (MK-7, 360 μg/daily, n = 61) or placebo (n = 62). Measurements at baseline and after 52 weeks of intervention included thrombin generation (endogenous thrombin potential, peak thrombin concentration, time to peak, and lag time); clot activities of vitamin K-dependent coagulation factors (F) II, VII, IX, and X; prothrombin fragment 1 + 2 (F1+2); and proteins induced by vitamin K absence II (PIVKA-II). Between-group differences (vitamin K vs. placebo) at 52 weeks were determined with an analysis of covariance. Within-group changes in vitamin K and placebo groups were analyzed with a paired t-test. Vascular adverse events and serious adverse events were registered based on hospital records, laboratory data, and participant interviews and compared between groups using Fisher's exact test or Pearson's Chi-Squared test., Results: A between-group difference at 52 weeks was observed for PIVKA-II (P < .001). PIVKA-II decreased significantly from baseline to 52 weeks in the vitamin K group, but not in the placebo group. We observed no between-group differences or within-group changes for biomarkers of coagulation, except for FVII clot activity which was reduced in the placebo group (P = .04), and no between-group differences in adverse events and serious adverse events., Conclusion: One year of vitamin K supplementation in patients on dialysis has no detectable effects on biomarkers of coagulation activation, clot activities of vitamin K-dependent coagulation factors, and vascular events or death, indicating no procoagulant effects of this treatment., (Copyright © 2023 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Phylloquinon (PK) and menaquinones (MK) are both naturally occurring compounds belonging to vitamin K group. Present study aimed to comprehensively analyze the influence of PK in several models of vascular dysfunction to determine whether PK has vasoprotective properties, similar to those previously described for MK. Effects of PK and MK on endothelial dysfunction were studied in ApoE/LDLR -/- mice in vivo, in the isolated aorta incubated with TNF, and in vascular cells as regard inflammation and cell senescence (including replicative and stress-induced models of senescence). Moreover, the vascular conversion of exogenous vitamins to endogenous MK-4 was analyzed. PK, as well as MK, given for 8 weeks in diet (10 mg/kg) resulted in comparable improvement in endothelial function in the ApoE/LDLR -/- mice. Similarly, PK and MK prevented TNF-induced impairment of endothelium-dependent vasorelaxation in the isolated aorta. In in vitro studies in endothelial and vascular smooth muscle cells, we identified that both PK and MK displayed anti-senescence effects via decreasing DNA damage while in endothelial cells anti-inflammatory activity was ascribed to the modulation of NFκB activation. The activity of PK and MK was comparable in terms of their effect on senescence and inflammation. Presence of endogenous synthesis of MK-4 from PK in aorta and endothelial and smooth muscle cells suggests a possible involvement of MK in vascular effects of PK. In conclusion, PK and MK display comparable vasoprotective effects, which may be ascribed, at least in part, to the inhibition of cell senescence and inflammation. The vasoprotective effect of PK in the vessel wall can be related to the direct effects of PK, as well as to the action of MK formed from PK in the vascular wall., (© 2024. The Author(s).)

Background: Hypoxic-ischemic encephalopathy (HIE) is a major contributor to neonatal mortality and neurodevelopmental disorders, but currently there is no effective therapy drug for HIE. Mitochondrial dysfunction plays a pivotal role in hypoxic-ischemic brain damage(HIBD). Menaquinone-4 (MK-4), a subtype of vitamin K2 prevalent in the brain, has been shown to enhance mitochondrial function and exhibit protective effects against ischemia-reperfusion injury. However, the impact and underlying molecular mechanism of MK-4 in HIE have not been fully elucidated., Methods: In this study, we established the neonatal rats HIBD model in vivo and oxygen-glucose deprivation and reperfusion (OGD/R) of primary neurons in vitro to explore the neuroprotective effects of MK-4 on HI damage, and illuminate the potential mechanism., Results: Our findings revealed that MK-4 ameliorated mitochondrial dysfunction, reduced oxidative stress, and prevented HI-induced neuronal apoptosis by activating the Sirt1-PGC-1α-TFAM signaling pathway through Sirt1 mediation. Importantly, these protective effects were partially reversed by EX-527, a Sirt1 inhibitor., Conclusion: Our study elucidated the potential therapeutic mechanism of MK-4 in neonatal HIE, suggesting its viability as an agent for enhancing recovery from HI-induced cerebral damage in newborns. Further exploration into MK-4 could lead to novel interventions for HIE therapy., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Two endophytic actinobacteria, strains MK5 T and MK7, were isolated from the surface-sterilized root of Jasmine rice (Oryza sativa KDML 105). These strains were aerobic actinobacteria with a well-developed substrate and aerial mycelia that formed spiral spore chains. The type strains that shared the high 16S rRNA gene sequence similarity with both strains were Streptomyces naganishii NBRC 12892 T (99.4%), "Streptomyces griseicoloratus" TRM S81-3 T (99.2%), and Streptomyces spiralis NBRC 14215 T (98.9%). Strains MK5 T and MK7 are the same species sharing a digital DNA-DNA hybridization (dDDH) value of 95.3% and a 16S rRNA gene sequence similarity of 100%. Chemotaxonomic data confirmed the affiliation of strains MK5 T and MK7 to the genus Streptomyces. Strains MK5 T and MK7 contained MK-9(H 4 ) as a major menaquinone; the whole-cell sugar of both strains was galactose and glucose. The strain MK5 T shared 93.4% average nucleotide identity (ANI)-Blast, 95.5% ANI-MUMmer, 93% average amino acid identity, and 61.3% dDDH with S. spiralis NBRC 14215 T . The polyphasic approach confirmed that strain MK5 T represents a novel species, and the name Streptomyces mahasarakhamensis sp. nov. is proposed. The type strain is MK5 T (= TBRC 17754 = NRRL B-65683). Genome mining, using an in silico approach and searching biosynthesis gene clusters of strains MK5 T and MK7, revealed that the genomes contained genes encoding proteins relating to plant growth promotion, bioactive compounds, and beneficial enzymes. Strains MK5 T and MK7 could produce indole acetic acid and solubilize phosphate in vitro., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

A Gram-stain-positive, aerobic bacterium, designated as YPD9-1 T , was isolated from the gut contents of a spotty belly greenling, Hexagrammos agrammus , collected near Dokdo island, South Korea. The rod-shaped cells were oxidase-positive, and catalase-negative. The major cellular fatty acids were anteiso-C 15 : 0 , iso-C 15 : 0 , C 16 : 0 , iso-C 16 : 0 and iso-C 17: 0 . The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and two unidentified lipids. The DNA G+C content was 47.6 mol% and the predominant respiratory quinone was menaquinone MK-7. The 16S rRNA gene sequence of YPD9-1 T showed low sequence similarities to species of the genus Paenibacillus , Paenibacillus pocheonensis Gsoil 1138 T (97.21 % of sequence similarity), Paenibacillus aestuarii CJ25 T (97.12 %) and Paenibacillus allorhizoplanae JJ-42 T (96.89 %). The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that YPD9-1 T formed a distinct branch among other species of the genus Paenibacillus . The digital DNA-DNA hybridisation, average nucleotide identity, and average amino acid identity values between YPD9-1 T and the related species were in the ranges of 15.3-16.2 %, 74.1-78.4 %, and 71.1-71.9 %, respectively, which are below the species cutoff values. On the basis of the results of the polyphasic analysis, we conclude that strain YPD9-1 T represents a novel species of the genus Paenibacillus , for which the name Paenibacillus hexagrammi sp. nov. is proposed. The type strain of Paenibacillus hexagrammi is YPD9-1 T (=KCTC 43424 T =LMG 32988 T ).

During a study on the diversity of culturable actinobacteria from coastal halophytes in Thailand, strain LSe6-5 T was isolated from leaves of sea purslane ( Sesuvium portulacastrum L.), and a polyphasic approach was employed to determine its taxonomic position. The 16S rRNA gene sequences analysis indicated that the strain was most closely related to Klenkia brasiliensis Tu 6233 T (99.2 %), Klenkia marina YIM M13156 T (99.1 %), and Klenkia terrae PB261 T (98.7 %). The genome of strain LSe6-5 T was estimated to be 4.33 Mbp in size, with DNA G+C contents of 74.3%. A phylogenomic tree based on whole-genome sequences revealed that strain LSe6-5 T formed a clade with Klenkia marina DSM 45722 T , indicating their close relationship. However, the average nucleotide identity (ANI)-blast, ANI-MUMmer, and dDDH values between strain LSe6-5 T with K. marina DSM 45722 T (87.1, 88.9, and 33.0 %) were below the thresholds of 95-96 % ANI and 70 % dDDH for identifying a novel species. Furthermore, strain LSe6-5 T showed morphological and chemotaxonomic characteristics of the genus Klenkia . Cells were motile, rod-shaped, and Gram-stain-positive. Optimal growth of strain LSe6-5 T occurred at 28 °C, pH 7.0, and 0-3 % NaCl. The whole-cell hydrolysates contained meso -diaminopimelic acid as the diagnostic diamino acid, with galactose, glucose, mannose, and ribose as whole-cell sugars. The predominant menaquinones were MK-9(H 4 ) and MK-9(H 0 ). The polar lipid profile was composed of diphosphatidylglycerol, hydroxyphosphatidylethanolamine, phosphatidylinositol, glycophosphatidylinositol, an unidentified phospholipid, and an unidentified lipid. Major cellular fatty acids were iso -C 15 : 0 , iso -C 16 : 0 , and iso -C 17 : 0 . From the distinct phylogenetic position and combination of genotypic and phenotypic characteristics, it is supported that strain LSe6-5 T represents a novel species of the genus Klenkia , for which the name Klenkia sesuvii sp. nov. is proposed. The type strain is strain LSe6-5 T (=TBRC 16417 T = NBRC 115929 T ).

Two Gram-stain-negative, rod-shaped, non-motile, strictly aerobic strains, forming yellow colonies and designated F6058 T and S2608 T , were isolated from marine sediment collected in Weihai, PR China. Both strains grow at 4-40 °C (optimum, 30-33 °C), pH 6.0-7.5 (optimum, pH 6.5) and in the presence of 0-7.0 % (w/v) NaCl. The optimum NaCl concentrations for strains F6058 T and S2608 T were 2.0 % and 2.5 %, respectively. Phylogenetic analysis of the 16S rRNA gene sequences indicated that strains F6058 T and S2608 T share an evolutionary lineage with members of the genus Aequorivita . The isolates exhibited a 16S rRNA gene sequence similarity of 96.7 % to each other. Strains F6058 T exhibited the highest 16S rRNA gene sequence similarity to Aequorivita xiaoshiensis F64183 T (98.8 %), and S2608 T was most similar to Aequorivita capsosiphonis A71 T (96.9 %). Iso-C 15:0 , anteiso-C 15:0 and iso-C 17:0 3-OH were the major fatty acids of strains F6058 T and S2608 T . The sole respiratory quinone of both isolates was menaquinone 6 (MK-6). The polar lipid profiles of the isolates both consisted of phosphatidylethanolamine and phosphoglycolipids; however, strain F6058 T exhibited one glycolipid, one aminolipid and two unidentified polar lipids, and strain S2608 T also had two glycolipids and one unidentified polar lipid. The DNA G+C contents of strains F6058 T and S2608 T were 34.6 % and 37.7 mol%, respectively. Based on their phenotypic, chemotaxonomic and genomic characteristics, strains F6058 T and S2608 T were considered to represent novel species of the genus Aequorivita , for which the names Aequorivita sediminis sp. nov. and Aequorivita marina sp. nov. were proposed. The type strains are F6058 T (=KCTC 92653 T =MCCC 1H01358 T ) and S2608 T (KCTC 92652 T =MCCC 1H01361 T ).

A Gram-stain-negative, orange-yellow, rod-shaped bacterium, designated strain SCSIO 19198 T , was isolated from sediment of the Haima cold seep in the South China Sea, PR China. The strain was aerobic and non-motile. Growth of strain SCSIO 19198 T occurred at pH 7-9 (optimum, pH 7), 15-37 °C (optimum, 25-32 °C) and with 3-8 % (w/v) NaCl (optimum, 3-6 % NaCl). Phylogenetic analyses based on 16S rRNA sequences revealed that strain SCSIO 19198 T belonged to the genus Hwangdonia , having the highest similarity to Hwangdonia seohaensis HD-3 T (98.35 %), followed by Algibacter aquimarinus KYW589 T (95.17 %) and Gelatiniphilus marinus GYP-24 T (94.89 %). The DNA G+C content was 35.92 mol%. The average nucleotide identity value between the genome of strain SCSIO 19198 T and that of H. seohaensis HD-3 T was 88.49 %. The digital DNA-DNA hybridization value between strain SCSIO 19198 T and H. seohaensis HD-3 T was 36 %. The major fatty acids (>10 %) of strain SCSIO 19198 T were iso-C 15 : 0 , iso-C 15 : 1 G, summed feature 3 (C 16 : 1  ω 6 c /C 16 : 1  ω7 c ) and anteiso-C 15 : 0 . MK-6 was the only detected respiratory quinone. The polar lipids of strain SCSIO 19198 T included phosphatidylethanolamine, two aminolipids, glycolipid and two unidentified lipids. The phenotypic, phylogenetic, chemotaxonomic and genomic data clearly suggest that strain SCSIO 19198 T represents a novel species of the genus Hwangdonia , for which the name Hwangdonia lutea sp. nov. is proposed. The type strain is SCSIO 19198 T (=MCCC 1K08674 T =KCTC 102078 T ).

Two bacteria, UG2&#95;1 T and UG2&#95;2, were isolated from the gill tissues of the mangrove fiddler crab Cranuca inversa collected on the east coast of the Red Sea (Thuwal, Saudi Arabia). The cells are Gram-negative, rod-shaped, orange-pigmented, motile by gliding with no flagella, strictly aerobic, and grow at 20-37 °C (optimum, 28-35 °C), at pH 5.0-9.0 (optimum, pH 6.0-7.0), and with 1-11 % (w/v) NaCl (optimum, 2-4 %). They were positive for oxidase and catalase activity. Phylogenetic analysis based on 16S rRNA gene sequences indicated that isolates UG2&#95;1 T and UG2&#95;2 belong to the genus Mangrovimonas , showing the highest similarity to Mangrovimonas spongiae HN-E26 T (99.4 %). Phylogenomic analysis based on the whole genomes, independently using 49 and 120 concatenated genes, showed that strains UG2&#95;1 T and UG2&#95;2 formed a monophyletic lineage in a different cluster from other type strain species within the genus Mangrovimonas . The genome sizes were 3.08 and 3.07 Mbp for UG2&#95;1 T and UG2&#95;2, respectively, with a G+C content of 33.8 mol% for both strains. Values of average nucleotide identity and digital DNA-DNA hybridization between the strains and closely related species were 91.0 and 43.5 %, respectively. Chemotaxonomic analysis indicated that both strains had iso-C 15 : 0 and iso-C 15 : 1 G as dominant fatty acids, and the primary respiratory quinone was identified as MK-6. The major polar lipids comprised phosphatidylethanolamine, one unidentified glycolipid, one unidentified phospholipid, two unidentified aminolipids, and four unidentified lipids. Based on phylogenetic, phylogenomic, genome relatedness, phenotypic, and chemotaxonomical data, the two isolates represent a novel species within the genus Mangrovimonas , with the proposed name Mangrovimonas cancribranchiae sp. nov., and the type strain UG2&#95;1 T (=KCTC 102158 T =DSM 117025 T ).

A Gram-stain-positive, rod-shaped, aerobic, motile bacterium, J379 T , was isolated from radioactive water spring C1, located in a former silver-uranium mine in the Czech Republic. This slow-growing strain exhibited optimal growth at 24-28 °C on solid media with <1 % salt concentration and alkaline pH 8-10. The only respiratory quinone found in strain J379 T was MK-7(H 4 ). C 18 : 1  ω9 c (60.9 %), C 18 : 0 (9.4 %), C 16 : 0 and alcohol-C 18 : 0 (both 6.2 %) were found to be the major fatty acids. The peptidoglycan contained directly cross-linked meso -diaminopimelic acid. Phylogenetic reconstruction based on the 16S rRNA gene sequences and the core-genome analysis revealed that strain J379 T forms a separate phylogenetic lineage within the recently amended order Solirubrobacterales . A comparison of the 16S rRNA gene sequences between strain J379 T and other members of the order Solirubrobacterales showed <96 % similarity. This analysis revealed that the closest type strains were Parviterribacter kavangonensis D16/0 /H6 T (95.2 %), Capillimicrobium parvum 0166&#95;1 T (94.9 %) and Conexibacter arvalis KV-962 T (94.5 %). Whole-genome analysis showed that the closest type strain was Baekduia soli BR7-21 T with an average nucleotide identity of 78 %, average amino acid identity of 63.2 % and percentage of conserved proteins of 48.2 %. The G+C content of the J379 T genomic DNA was 71.7 mol%. Based on the phylogenetic and phylogenomic data, as well as its physiological characteristics, strain J379 T is proposed to represent a type strain (DSM 113746 T =CCM 9300 T ) of Svornostia abyssi gen. nov. sp. nov. within the family Baekduiaceae .

Vitamin K possesses efficacy as a topical dermatological agent. However, vitamin K is phototoxic and susceptible to photodegradation. Herein, we investigated the mechanisms underlying the phototoxicity of phylloquinone (PK, vitamin K 1 ) and menaquinone-4 (MK-4, vitamin K 2 ) under ultraviolet A (UVA) irradiation using various reactive oxygen species (ROS) scavengers. This resulted in the production of superoxide anion radicals via type I and singlet oxygen via type II photodynamic reactions, which were quenched by the ROS scavengers: superoxide dismutase and sodium azide (NaN 3 ). In HaCaT cells, MK-4 and PK induced the production of intracellular ROS, particularly hydrogen peroxide, in response to UVA irradiation. Furthermore, the addition of catalase successfully decreased maximum ROS levels by approximately 30%. NaN 3 and catalase decreased the maximum reduction in cell viability induced by UVA-irradiated PK and MK-4 in cell viability by approximately 2-7-fold. Additionally, ROS scavengers had no effect on the photodegradation of PK or MK-4 at 373 nm. Therefore, the phototoxicities of PK and MK-4 were attributed to the generation of singlet oxygen and hydrogen peroxide, underscoring the importance of photoshielding in circumventing phototoxicity., Competing Interests: Declaration of competing interest The authors have no conflict of interest to declare., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Two Gram-stain-positive, aerobic, oxidase- and catalase-negative, non-motile, and short rod-shaped actinomycetes, named SYSU T00b441 T and SYSU T00b490, were isolated from tidal flat sediment located in Guangdong province, PR China. The 16S rRNA gene sequence similarity, average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between SYSU T00b441 T and SYSU T00b490 were 99.3, 99.5 and 97.1 %, respectively. Strains SYSU T00b441 T and SYSU T00b490 exhibited the highest 16S rRNA gene sequence similarities to Actinotalea ferrariae CF 5-4 T (97.1 %/98.2 %), with ANI values of 74.01/73.88 % and dDDH values of 20.5/20.4 %. In the phylogenomic tree, the two isolates were affiliated with the genus Actinotalea . The genomes of strains SYSU T00b441 T and SYSU T00b490 were 3.31 and 3.34 Mb, and both had DNA G+C contents of 72.8 mol%, coding 3077 and 3085 CDSs, three and three rRNA genes, and 53 and 51 tRNAs, respectively. Growth occurred at 15-40 °C (optimum, 28-30 °C), pH 4.0-10.0 (optimum, 7.0) and in the presence of 0-7 % (w/v) NaCl (optimum, 3 %). The major fatty acids (>10  %) of strains SYSU T00b441 T and SYSU T00b490 were anteiso-C 15 : 0 and C 16 : 0 . The major respiratory quinone was identified as MK-10(H 4 ). The polar lipids of strains SYSU T00b441 T and SYSU T00b490 were diphosphatidyl glycerol, phosphatidylglycerol, phosphoglycolipid, phosphatidyl ethanolamine, two phosphatidylinositol mannosides, two glycolipids and two phospholipids. Based on these data, the two strains (SYSU T00b441 T and SYSU T00b490) represent a novel species of the genus Actinotalea , for which the name Actinotalea lenta sp. nov is proposed. The type strain is SYSU T00b441 T (=GDMCC 1.3827 T =KCTC 49943 T ).

Strain I65 T (=KACC 22647 T =JCM 35315 T ), a novel Gram-stain-negative, strictly aerobic, non-motile, non-spore-forming, rod-shaped, and orange-pigmented bacterium was isolated from influent water of a wastewater treatment system after treatment with several antibiotics, such as meropenem, gentamicin, and macrolide. The newly identified bacterial strain I65 T exhibits significant multi-drug and heavy metal resistance characteristics. Strain I65 T was grown in Reasoner's 2A medium [0 %-2 % (w/v) NaCl (optimum, 0 %), pH 5.0-10.0 (optimum, pH 7.0), and 20-45°C (optimum, 30 °C)]. Phylogenetic analysis based on 16S rRNA gene sequencing confirmed that strain I65 T was closely related to Niabella yanshanensis CCBAU 05354 T (99.56 % sequence similarity), Niabella hibiscisoli THG-DN5.5 T (97.51 %), and Niabella ginsengisoli GR10-1 T (97.09 %). Further analysis of the whole-genome sequence confirmed that the digital DNA-DNA hybridization, average nucleotide identity, and average amino acid identity values between strain I65 T and N. yanshanensis CCBAU 05354 T were 23.4, 80.7, and 85.0 %, respectively, suggesting that strain I65 T is distinct from N. yanshanensis . The genome size of strain I65 T was 6.1 Mbp, as assessed using the Oxford Nanopore platform, and its genomic DNA G+C content was 43.0 mol%. The major fatty acids of strain I65 T were iso-C 15 : 0 and iso-C 15 : 1 G, and the major respiratory quinone was MK-7. Moreover, the major polar lipid of strain I65 T was phosphatidylethanolamine. Based on genotypic, chemotaxonomic, and phenotype data, strain I65 T represents a novel species belonging to the genus Niabella , for which the name Niabella defluvii sp. nov. is proposed. The type strain is I65 T (=KACC 22647 T =JCM 35315 T ).

A Gram-stain-negative, aerobic, non-spore-forming, nonmotile, rod-shaped, and yellow-pigmented bacterium, designated strain JXAS1 T , was isolated from a freshwater sample collected from Poyang Lake in China. Phylogenetic analysis based on 16S rRNA gene sequence revealed that the isolate belonged to the genus Flavobacterium , being closest to Flavobacterium pectinovorum DSM 6368 T (98.61 %). The genome size of strain JXAS1 T was 4.66 Mb with DNA G+C content 35.7 mol%. The average nucleotide identity and in silico DNA-DNA hybridization values between strain JXAS1 T and its closest relatives were below the threshold values of 95 and 70 %, respectively. The strain contained menaquinone 6 (MK-6) as the predominant menaquinone and the major polar lipids were phosphatidylethanolamine, one unidentified glycolipid, and one unidentified polar lipid. The major fatty acids (>5 %) were iso-C 15 : 0 , summed feature 3 (C 16 : 1  ω 7 c and/or C 16 : 1  ω 6 c ), C 15 : 0 , iso-C 17 : 0 3OH, iso-C 15 : 0 3OH, and summed feature 9 (iso-C 17 : 1  ω 9 c and/or 10-methyl C 16 : 0 ). Based on phylogenetic, genotypic, and phenotypic evidence, the isolated strain represents a new species in the genus Flavobacterium , and the name Flavobacterium poyangense is proposed. The type strain is JXAS1 T (=GDMCC 1.1378 T =KCTC 62719 T ).

A Gram-stain-positive, rod-shaped bacterium, designated as HLT2-17 T , was isolated from soil sample taken from the Hailuogou glacier in Sichuan province, PR China. Strain HLT2-17 T was capable of growing at 4-25°C and in NaCl concentrations ranging from 0 to 2% (w/v). The highest level of 16S rRNA gene sequence similarity was observed with Pengzhenrongella phosphoraccumulans M0-14 T (98.3 %) and Pengzhenrongella sicca LRZ-2 T (98.2 %). The average nucleotide identity and digital DNA-DNA hybridization values between strain HLT2-17 T and its closest relatives, P. phosphoraccumulans M0-14 T and P. sicca LRZ-2 T , were 80.0-84.0 % and 23.3-27.7 %, respectively. Phylogenomic analysis indicated that strain HLT2-17 T clustered together with strains P. phosphoraccumulans M0-14 T and P. sicca LRZ-2 T . Strain HLT2-17 T contained C 16 : 0 and anteiso-C 15 : 0 as the major fatty acids, and MK-9(H 4 ) as the menaquinone. Therefore, based on a polyphasic approach, we propose that strain HLT2-17 T (=CGMCC 1.11116 T = NBRC 110443 T ) represents a novel species of the genus Pengzhenrongella and suggest the name Pengzhenrongella frigida sp. nov.

Vitamin K2 (VK2) is an effective compound for anti-ferroptosis and anti-osteoporosis, and Semen sojae praeparatum (Dandouchi in Chinese) is the main source of VK2. Chondrocyte ferroptosis and extracellular matrix (ECM) degradation playing a role in the pathogenesis of osteoarthritis (OA). Glutathione peroxidase 4 (GPX4) is the intersection of two mechanisms in regulating OA progression. But no studies have elucidated the therapeutic effects and mechanisms of VK2 on OA. This study utilized an in vivo rat OA model created via anterior cruciate ligament transection (ACLT) and an in vitro chondrocyte oxidative damage model induced by TBHP to investigate the protective effects and mechanisms of action of VK2 in OA. Knee joint pain in mice was evaluated using the Von Frey test. Micro-CT and Safranin O-Fast Green staining were employed to observe the extent of damage to the tibial cartilage and subchondral bone, while immunohistochemistry and PCR were used to examine GPX4 levels in joint cartilage. The effects of VK2 on rat chondrocyte viability were assessed using CCK-8 and flow cytometry assays, and chondrocyte morphology was observed with toluidine blue and alcian blue staining. The impact of VK2 on intracellular ferroptosis-related markers was observed using fluorescent staining and flow cytometry. Protein expression changes were detected by immunofluorescence and Western blot analysis. Furthermore, specific protein inhibitors were applied to confirm the dual-regulatory effects of VK2 on GPX4. VK2 can increase bone mass and cartilage thickness in the subchondral bone of the tibia, and reduce pain and the OARSI score induced by OA. Immunohistochemistry results indicate that VK2 exerts its anti-OA effects by regulating GPX4 to delay ECM degradation. VK2 can inhibit the activation of the MAPK/NFκB signaling pathway caused by reduced expression of intracellular GPX4, thereby decreasing ECM degradation. Additionally, VK2 can reverse the inhibitory effect of RSL3 on GPX4, increase intracellular GSH content and the GSH/GSSG ratio, reduce MDA content, and rescue chondrocyte ferroptosis. The protective mechanism of VK2 may involve its dual-target regulation of GPX4, reducing chondrocyte ferroptosis and inhibiting the MAPK/NFκB signaling pathway to decelerate the degradation of the chondrocyte extracellular matrix., Competing Interests: Declaration of Competing Interest All the authors have declared that no competing interest exists, (Copyright © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Strain wdc7 T , a rod-shaped bacterium, was isolated from soil in the Gotjawal Forest on Jeju Island, South Korea. Strain wdc7 T was Gram stain-negative, facultatively anaerobic, catalase- and oxidase positive, yellow pigmented, and non-flagellated. It grew at 4-37 °C and pH 5.0-8.0 in 0-3% (w/v) NaCl. 16S rRNA gene sequencing analysis revealed that strain wdc7 T belonged to the genus Chryseobacterium and was most closely related to Chryseobacterium salivictor NBC 122 T , with a sequence similarity of 98.51%. Menaquinone 6 was the sole respiratory quinone, and C 15:0 anteiso, C 15:0 iso, and summed feature 9 were the major fatty acids. The genome length was 3.30 Mbp, with a 37% G + C content. Average amino acid identity, average nucleotide identity, and digital DNA-DNA relatedness between strain wdc7 T and C. salivictor NBC 122 T were 93.52%, 92.80%, and 49.7%, respectively. Digital genomic and polyphasic analyses showed that strain wdc7 T likely represented a new species of the genus Chryseobacterium. We proposed the name Chryseobacterium gotjawalense sp. nov., with wdc7 T (= KCTC 92440 T  = JCM 35602 T ) as the type strain., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

An aerobic, Gram-stain-negative and short rod-shaped bacterial strain, designated M6-31 T , was isolated from rice paddy soil sampled in Miryang, Republic of Korea. Growth was observed at 4-35 °C (optimum, 28 °C), pH 6.0-9.0 (optimum, pH 7.0-8.0) and in the presence of 0-4 % (w/v) NaCl (optimum, 0 % w/v). Phylogenetic analysis based on 16S rRNA gene sequences grouped strain M6-31 T with Sphingobacterium bambusae IBFC2009 T , Sphingobacterium griseoflavum SCU-B140 T and Sphingobacterium solani MLS-26-JM13-11 T in the same clade, with the 16S rRNA gene sequence similarities ranging from 95.8 to 96.6 %. A genome-based phylogenetic tree reconstructed by using all publicly available Sphingobacterium genomes placed strain M6-31 T with S. bambusae KACC 22910 T , ' Sphingobacterium deserti ' ACCC 05744 T , S. griseoflavum CGMCC 1.12966 T and Sphingobacterium paludis CGMCC 1.12801 T . Orthologous average nucleotide identity and digital DNA-DNA hybridization values between strain M6-31 T and its closely related strains were lower than 74.6 and 22.0 %, respectively. The respiratory quinone was menaquinone-7, and the major polar lipid was phosphatidylethanolamine. The major fatty acids (>10 %) were C 15 : 0 iso, C 17 : 0 iso 3OH and summed feature 3. The phenotypic, chemotaxonomic and genotypic data obtained in this study showed that strain M6-31 T represents a novel species of the genus Sphingobacterium , for which the name Sphingobacterium oryzagri sp. nov. (type strain M6-31 T =KACC 22765 T =JCM 35893 T ) is proposed.

A Gram-stain-positive, aerobic, non-mobile and spherical strain, designated ZS9-10 T , belonging to the genus Deinococcus was isolated from soil sampled at the Chinese Zhong Shan Station, Antarctica. Growth was observed in the presence of 0-4 % (w/v) NaCl, at pH 7.0-8.0 and at 4-25 °C. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain ZS9-10 T formed a lineage in the genus Deinococcus . It exhibited highest sequence similarity (97.4 %) to Deinococcus marmoris DSM 12784 T . The major phospholipids of ZS9-10 T were unidentified phosphoglycolipid, unidentified glycolipids and unidentified lipids. The major fatty acids were summed feature 3 (C 16 : 1  ω 7 c and/or C 16 : 1  ω 6 c ), C 16 : 0 and C 16 : 1  ω 7 c . MK-8 was the predominant respiratory quinone. The digital DNA-DNA hybridization and average nucleotide identity values between strain ZS9-10 T and its close relative D. marmoris DSM 12784 T were 27.4 and 83.9 %, respectively. Based on phenotypic, phylogenetic and genotypic data, a novel species, named Deinococcus arenicola sp. nov., is proposed. The type strain iis ZS9-10 T (=CCTCC AB 2019392 T =KCTC43192 T ).

Two novel actinobacteria, designated as LP05-1 T and LP11 T , were isolated from the lichen Pyxine cocoes (Sw.) Nyl. collected in Bangkok, Thailand. Genotypic and phenotypic analyses revealed that both strains represented members of the genus Streptomyces . The 16S rRNA gene of LP05-1 T showed the highest similarity to the genome of Streptomyces gelaticus (98.41 %), while the 16S rRNA gene of LP11 T was most similar to that of Streptomyces cinerochromogenes (98.93 %). The major menaquinones in LP05-1 T were MK-9(H 8 ), MK-9(H 6 ), MK-9(H 4 ) and MK-9(H 2 ), and in LP11 T , they were MK-9(H 8 ) and MK-9(H 6 ). Both strains exhibited the major fatty acids iso-C 15 : 0 , anteiso-C 15 : 0 , iso-C 16 : 0 and anteiso-C 17 : 0 , with LP05-1 T also possessing iso-C 17 : 0 . The polar lipids of LP05-1 T included phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannoside and an unidentified lipid, while those of LP11 T consisted of phosphatidylethanolamine, lyso -phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannoside, an unidentified aminolipid and an unidentified glycolipid. The digital DNA-DNA hybridisation (dDDH) and average nucleotide identity (ANI) values indicated that both strains are distinct from each other with values below 70 and 95 %, respectively. dDDH, ANI by blast (ANIb) and ANI by MUMmer (ANIm) values between LP05-1 T and its closely related type strains were 26.07-26.80 %, 81.24-82.01 % and 86.82-86.96 %, respectively, while those for LP11 T and its closely related type strains were 30.70-31.70 %, 84.09-85.31 % and 88.02-88.39 %, respectively. The results of the taxonomic investigation, including dDDH and ANI values, indicate that LP05-1 T and LP11 T are novel type strains of two novel species within the genus Streptomyces . The names proposed are Streptomyces pyxinae sp. nov. for strain LP05-1 T (=TBRC 15494 T , =NBRC 115434 T ) and Streptomyces pyxinicus sp. nov. for strain LP11 T (=TBRC 15493 T , =NBRC 115421 T ).

A novel Gram-staining-positive actinobacterium with antimicrobial activity, designated CFH 90308 T , was isolated from the sediment of a salt lake in Yuncheng, Shanxi, south-western China. The isolate exhibited the highest 16S rRNA gene sequence similarities to Microbacterium yannicii G72 T , Microbacterium hominis NBRC 15708 T and Microbacterium xylanilyticum S3-E T (98.5, 98.4 and 98.2 %, respectively), and formed a separate clade with M. xylanilyticum S3-E T in phylogenetic trees. The strain grew at 15-40 ºC, pH 6.0-8.0 and could tolerate NaCl up to a concentration of 15 % (w/v). The whole genome of strain CFH 90308 T consisted of 4.33 Mbp and the DNA G+C content was 69.6 mol%. The acyl type of the peptidoglycan was glycolyl and the whole-cell sugars were galactose and mannose. The cell-wall peptidoglycan mainly contained alanine, glycine and lysine. The menaquinones of strain CFH 90308 T were MK-12, MK-13 and MK-11. Strain CFH 90308 T contained anteiso-C 15:0 , anteiso-C 17:0 , iso-C 16:0 and iso-C 15:0 as the predominant fatty acids. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between CFH 90308 T and the other species of the genus Microbacterium were found to be low (ANIb <81.3 %, dDDH <25.6 %). The secondary metabolite produced by strain CFH 90308 T showed antibacterial activities against Bacillus subtilis , Pseudomonas syringae , Aeromonas hydrophila and methicillin-resistant Staphylococcus aureus . Based on genotypic, phenotypic and chemotaxonomic results, the isolate is considered to represent a novel species of the genus Microbacterium , for which the name Microbacterium salsuginis sp. nov . is proposed. The type strain is CFH 90308 T (=DSM 105964 T =KCTC 49052 T ).