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A polyphasic taxonomic study was carried out on strain T5W1 T , isolated from the roots of the aquatic plant Spirodela polyrhiza . This isolate is Gram-negative, rod-shaped, motile, aerobic and non-pigmented. Nearly complete 16S rRNA gene sequence homology related the strain to Pseudomonas , with 98.4% similarity to P. guineae , P. peli and P. leptonychotis . Average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) with the closest phylogenetic neighbour of T5W1 T showed differences at the species level, further confirmed by differences in several physiological characteristics. The main fatty acids are summed feature 3 (C 16 : 1   ω7c and/or C 16 : 1 . The DNA G+C content is 59.3 mol%. Q-9 is the primary ubiquinone found, and phosphatidylethanolamine is the dominant polar lipid, with lesser amounts of phosphatidylglycerol, diphosphatidylglycerol and phosphatidylserine. Based on the results obtained, this bacterium is assigned to the genus   ω6c ), C 18 : 1   ω7c , and C 16 : 0 . The DNA G+C content is 59.3 mol%. Q-9 is the primary ubiquinone found, and phosphatidylethanolamine is the dominant polar lipid, with lesser amounts of phosphatidylglycerol, diphosphatidylglycerol and phosphatidylserine. Based on the results obtained, this bacterium is assigned to the genus Pseudomonas as a new species with the name Pseudomonas spirodelae sp. nov., type strain T5W1 T (=NRRL B-65714 T =DSM 118085 T ).

Two Gram-stain-negative, motile, non-spore-forming, aerobic or facultative anaerobic and short rod-shaped bacterial strains, 25B02-3 T and BH-R2-4, were isolated from surface seawater collected from the Bering Sea and Chukchi Sea, respectively. The 16S rRNA gene sequences of the two strains were identical. The phylogenetic analysis of the 16S rRNA gene sequences indicated that they were related to the genus Tistrella and shared 99.6 and 98.2% sequence similarity with T. bauzanensis BZ78 T and T. mobilis IAM 14872 T , respectively. Both 16S rRNA gene and genome sequence-based phylogenetic analyses showed that the two strains formed a monophyletic clade within the genus Tistrella , indicating that they may represent a novel species. The digital DNA‒DNA hybridization (dDDH) values and average nucleotide identities (ANI) between the two strains were 93 and 99%, respectively, indicating that they are different strains. The dDDH and ANI values between the two strains and the type strains of the genus Tistrella were 22.4-58.3% and 81.0-95.0%, respectively. These data clearly demonstrated that the two strains represent a separate genomic species of the genus Tistrella . The principal fatty acids were Sum In Feature 8 (C 18 : 1 ω7 c or C 18 : 1 ω6 c), C 19 : 0 cyclo ω 8 c , Sum In Feature 2 (C 12 : 0 aldehyde or unknown 10.928) and C 16 : 0 . The predominant respiratory quinone was Q-10, with a minor Q-9. The polar lipids included phosphatidylethanolamine, aminolipids and phospholipids. The genomic DNA G+C contents of strains 25B02-3 T and BH-R2-4 were 67.3 mol% and 67.4 mol%, respectively. On the basis of the polyphasic evidence presented in this study, the two strains represent a novel species within the genus Tistrella , for which the name Tistrella arctica sp. nov. is proposed. The type strain is 25B02-3 T (=MCCC 1A07333 T =KCTC 8340 T ).

Marine biofilms were newly revealed as a bank of hidden microbial diversity and functional potential. In this study, a Gram-stain-negative, aerobic, oval and non-motile bacterium, designated LMIT008 T , was isolated from the biofilm of concrete breakwater structures located in the coastal area of Shantou, PR China. Strain LMIT008 T was found to grow at salinities of 1-7% NaCl, at pH 5-8 and at temperatures 10-40 °C. Phylogenetic analysis based on 16S rRNA gene sequence indicated that strain LMIT008 T belonged to the genus Jannaschia and was closely related to the type strains Jannaschia aquimarina KCTC23555 T (96.03%) and Jannaschia marina SHC-163 T (95.31%). The draft genome size of the strain LMIT008 T was 3.67 Mbp, and the genomic DNA G+C content was 69.83 mol%. The average nucleotide identity value between strain LMIT008 T and the closely related type strain J. aquimarina KCTC23555 T was 74.82%. The predominant cellular fatty acids were identified as summed feature 8 (C 18 : 1  ω 7 c /C 18 : 1  ω , and the major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine. Ubiquinone-10 (Q-10) is the sole respiratory quinone. Further, genomic analysis of strain LMIT008 c ) and C 18 : 0 , and the major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine. Ubiquinone-10 (Q-10) is the sole respiratory quinone. Further, genomic analysis of strain LMIT008 T showed that the strain harbours abundant genes associated with biofilm formation and environmental adaption, explaining the potential strategies for living on concrete breakwater structures. Based on the morphological, phylogenetic, chemotaxonomic and phenotypic characterization, the strain LMIT008 T was considered to represent a novel species in the genus of Jannaschia , for which the name Jannaschia maritima sp. nov. was proposed, with LMIT008 T (=MCCC 1K08854 T =KCTC 8321 T ) as the type strain.

Two Gram-stain-negative bacterial strains, BSw22131 T and DMSP-1 T , were isolated from seawater of Arctic Kongsfjorden in the Ny-Ålesund area, Svalbard. Strains BSw22131 T and DMSP-1 T were within the genus Pseudomonas and presented 98.1 and 99.8% 16S rRNA gene sequence similarity to Pseudomonas piscicola P50 T and Pseudomonas paracarnis V5/DAB/2/5 T , respectively. However, the results of multilocus sequence analysis (concatenated 16S rRNA, gyrB , rpoB and rpoD gene sequences) and whole-genome sequence analysis indicated that BSw22131 T and DMSP-1 T were most closely related to Pseudomonas petrae P2653 T and Pseudomonas lactis DSM 29167 T , respectively. The genome G+C contents of strains BSw22131 T and DMSP-1 T were 58.2 and 60.0%, respectively. The two isolates presented digital DNA-DNA hybridization and average nucleotide identity values of less than 70 and 96%, respectively, with type strain genomes of their close relatives. BSw22131 T contained summed feature 3 (C 16 : 1  ω6 c / C1 6 : 1  ω7 c), C 16 : 0 and summed feature 8 (C 18 : 1  ω6 c / C1 8 : 1  ω7 c) as the major cellular fatty acids, whereas DMSP-1 T contained an additional C 17 : 0 -cyclo as the major fatty acid. The major quinones of both strains were Q-9 (57.5-77.2%) and Q-8 (22.8-37.2%), and their major cellular polar lipids were diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. BSw22131 T could be differentiated from its related species by positive ornithine decarboxylase, esterase (C8) and l-rhamnose and d-fructose-6-PO 4 utilization, whereas DMSP-1 T could be differentiated by positive acid phosphatase but negative p -hydroxyphenylacetic acid utilization. The two strains were negative for the reduction of nitrates but contained genes related to dimethylsulfoniopropionate catabolism. The results of the polyphasic taxonomy analysis revealed that strains BSw22131 T and DMSP-1 T represent two novel species of the genus Pseudomonas , for which the names Pseudomonas huanghezhanensis sp. nov. (type strain BSw22131 T = CCTCC AB 2019135 T = JCM 36635 T = DSM 117336 T ) and Pseudomonas fjordensis sp. nov. (type strain DMSP-1 T = CCTCC AB 2019124 T = JCM 36636 T = DSM 117337 T ) are proposed.

The photosynthetic microorganisms within the coral holobiont produce energy and organic compounds through photosynthesis, which are vital for the biocalcification and heat tolerance of coral hosts. However, aerobic anoxygenic phototrophic bacteria (AAPB), which are one of the most important photosynthetic microorganisms, have not been thoroughly investigated in this environment. In this study, a novel AAPB, SCSIO 66989 T , was isolated from the reef-building coral Favia sp. and considered a beneficial microorganism for corals (BMC). The polyphasic taxonomic analysis showed that it had the highest similarities with Parasphingorhabdus litoris DSM 22379 T (95.9%) and Altererythrobacter ishigakiensis ATCC BAA-2084 T (95.7%). Phylogenetic analysis showed that it formed an independent clade, distinguishing it from other genera within the family Sphingomonadaceae . The predominant fatty acids were C 18 : 1  ω7 c and/or C 18 : 1 . The major respiratory quinone was ubiquinone-10 (Q-10). Sphingolipid, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine were the diagnostic polar lipids. The average nucleotide identity, average amino acid identity and digital DNA-DNA hybridization values between SCSIO 66989  ω6 c and C 16 : 0 . The major respiratory quinone was ubiquinone-10 (Q-10). Sphingolipid, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine were the diagnostic polar lipids. The average nucleotide identity, average amino acid identity and digital DNA-DNA hybridization values between SCSIO 66989 T and the type strains of P. litoris DSM 22379 T and A. ishigakiensis ATCC BAA-2084 T were 69.2-70.0%, 58.6-61.2% and 19.2-19.7%, respectively. These results indicate that strain SCSIO 66989 T represents a new species of a novel genus in the family Sphingomonadaceae , for which the name Alterisphingorhabdus coralli gen. nov. sp. nov. is proposed.

Two yellow-pigmented novel strains, designated HF-S3 T and HF-S4 T , were isolated from farm soil in Paju, Republic of Korea. Cells of the two strains are characteristically Gram-stain-negative, facultatively anaerobic, catalase- and oxidase-positive, non-motile and rod-shaped. Strain HF-S3 T grew at 10-37 °C, while HF-S4 T grew at 15-35 °C. Both strains grew at pH 5.0-12.0 and in NaCl concentrations (w/v) of 0-2.0%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that HF-S3 T and HF-S4 T belong to the genus Sphingomonas , with HF-S3 T exhibiting 97.7, 97.6 and 97.4% similarity to Sphingomonas cannabina DM2-R-LB4 T , Sphingomonas leidyi DSM 4733 T and Sphingomonas canadensis FWC47 T , respectively. Strain HF-S4 T displayed 97.9, 97.7 and 97.6% similarity to Sphingomonas psychrotolerans Cra20 T , Sphingomonas gei ZFGT-11 T and Sphingomonas naasensis KIS18-15 T , respectively. The DNA G+C contents of HF-S3 T and HF-S4 T were 67.0 and 66.5 mol%, respectively. The digital DNA-DNA hybridization and average nucleotide identity values among the novel and related type strains were 20.2-28.2% and 75.9-84.3%, respectively. They all contained C 14:0 2-OH and C 16:0 , summed feature 8 (C 18:1 ω 6 c and/or C 18:1 ) as the major fatty acids and ubiquinone-10 as the predominant respiratory quinone. Strains HF-S3 ω 7 c ) as the major fatty acids and ubiquinone-10 as the predominant respiratory quinone. Strains HF-S3 T and HF-S4 T were found to produce carotenoid-type pigments. Based on polyphasic taxonomic analysis, the new isolates ostensibly represent two novel species of the genus Sphingomonas , with the proposed names Sphingomonas rustica sp. nov. and Sphingomonas agrestis sp. nov. for strains HF-S3 T and HF-S4 T , respectively. The S. rustica and S. agrestis type strains are HF-S3 T (=KACC 23554 T =TBRC 18352 T ) and HF-S4 T (=KACC 23386 T =TBRC 17899 T ), respectively.

Two Gram-stain-negative, aerobic, ovoid to short rod-shaped bacterial strains, designated as WL0062 T and WL0115, were isolated from coastal zone of the Yellow Sea, Jiangsu Province, PR China, respectively. Strain WL0062 T grew optimally at 28 °C, pH 7.0-8.0 and with 1.0-3.0% (w/v) NaCl. Strain WL0115 grew optimally at 28 °C, pH 6.0-7.0 and with 1.0-3.0% (w/v) NaCl. In the bac120 tree, strains WL0062 T and WL0115 clustered together with Sedimentimonas flavescens B57 T . The respiratory quinone of both strains was ubiquinone-10. The major polar lipids of both strains were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, glycolipid, phosphatidylmonomethylethanolamine, and one unidentified polar lipid. The major fatty acids of strain WL0062 T were summed features 8 (C 18 : 1  ω 6 c and/or C 18 : 1  ω 7 c ). The major fatty acids of strain WL0115 were summed features 8 (C 18 : 1  ω 6 c and/or C 18 : 1  ω 7 c ), C 18 : 0 , iso-C 17 : 1  ω 5 c and C 20 : 4  ω 6/9/12/15 c (arachidonic acid). The G+C content of genomic DNA of strains WL0062 T and WL0115 was 64.0 mol% in both of them. Combined with the analysis of average nucleotide identity, average amino acid identity, and digital DNA-DNA hybridization, strain WL0062 T represents a novel species of the genus Rhodobacter , for which the name Rhodobacter flavimaris sp. nov is proposed. The type strain is WL0062 T (=MCCC 1K06014 T =JCM 34676 T =GDMCC 1.2427 T ). Strain WL0115 (=MCCC 1K07531=JCM 35568=GDMCC 1.3088) should belong to the same species as Sedimentimonas flavescens B57 T . In addition, on the basis of phylogenomic relationship and phenotypical characteristics, the genera Paenirhodobacter , Sedimentimonas , and Sinirhodobacter are proposed as synonyms of Rhodobacter .

Six bacterial strains, Mut1 T , Mut2, Alt1, Alt2, Alt3 T , and Alt4, were isolated from soil samples collected in parks in Gothenburg, Sweden, based on their ability to utilize the insoluble polysaccharides α-1,3-glucan (mutan; Mut strains) or the mixed-linkage α-1,3/α-1,6-glucan (alternan; Alt strains). Analysis of 16S rRNA gene sequences identified all strains as members of the genus Streptomyces . The genomes of the strains were sequenced and subsequent phylogenetic analyses identified Mut2 as a strain of Streptomyces laculatispora and Alt1, Alt2 and Alt4 as strains of Streptomyces poriferorum, while Mut1 T and Alt3 T were most closely related to the type strains Streptomyces drozdowiczii NBRC 101007 T and Streptomyces atroolivaceus NRRL ISP-5137 T , respectively. Comprehensive genomic and biochemical characterizations were conducted, highlighting typical features of Streptomyces , such as large genomes (8.0-9.6 Mb) with high G+C content (70.5-72.0%). All six strains also encode a wide repertoire of putative carbohydrate-active enzymes, indicating a capability to utilize various complex polysaccharides as carbon sources such as starch, mutan, and cellulose, which was confirmed experimentally. Based on phylogenetic and phenotypic characterization, our study suggests that strains Mut1 T and Alt3 T represent novel species in the genus Streptomyces for which the names Streptomyces castrisilvae sp. nov. and Streptomyces glycanivorans sp. nov. are proposed, with strains Mut1 T (=DSM 117248 T =CCUG 77596 T ) and Alt3 T (=DSM 117252 T =CCUG 77600 T ) representing the respective type strains.

A Gram-stain-negative, non-spore-forming and strictly aerobic bacterial strain, designated R-7 T , was isolated from river sediment in Wuxi, Jiangsu, PR China. Cells (1.6-3.8 µm long and 0.6-0.8 µm wide) were slightly curved to straight rods and motile by means of a polar flagellum. The strain grew optimally on Reasoner's 2A medium at 30 °C, pH 7.0 and with 1.0% (w/v) NaCl. Strain R-7 T exhibited closest 16S rRNA gene sequence similarities to Dongia mobilis CGMCC 1.7660 T (95.4%), D. rigui 04SU4-P T (94.6%) and D. soli D78 T (93.8%). The phylogenetic trees based on genomic and 16S rRNA gene sequences showed that strain R-7 T was clustered in the genus Dongia . The obtained average nucleotide identity and digital DNA-DNA hybridization values between R-7 T and the three type strains of the genus Dongia were 73.4, 72.8 and 72.4% and 19.5, 19.0 and 18.7%, respectively. The major respiratory quinone was Q-10. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, three unidentified aminolipids, two unidentified aminophospholipids and nine unidentified polar lipids. The major cellular fatty acids (>5% of the total) were cyclo-C 19 : 0  ω 8 c , C 16 : 0 and C 16 : 0 2-OH. The DNA G+C content was 65.5 mol%. On the basis of the evidence presented in this study, strain R-7 T represents a novel species of the genus Dongia , for which the name Dongia sedimenti sp. nov. is proposed, with strain R-7 T (=KCTC 8082 T =MCCC 1K08805 T ) as the type strain.

Two Gram-negative, obligately aerobic, rod-shaped bacteria, strains G1-22 T and G1-23 T , were isolated from the phycosphere of a marine brown alga. Both strains exhibited catalase- and oxidase-positive activities. Strain G1-22 T displayed optimal growth at 25 °C, pH 8.0, and 2.0-3.0% (w/v) NaCl, while strain G1-23 T exhibited optimal growth at 25 °C, pH 8.0, and 4.0% NaCl. Ubiquinone-8 was identified as the sole isoprenoid quinone in both strains. As major fatty acids (> 5%), strain G1-22 T contained C 16 : 0 , summed feature 3 (C 16 : 1 ω 7 c and/or C 16 : 1 ω 6 c ), summed feature 8 (C 18 : 1 ω 7 c and/or C 18 : 1 ω 6 c ), C 12 : 1 3-OH, and C 10 : 0 3-OH, while strain G1-23 T contained C 16 : 0 , summed feature 3 (C 16 : 1 ω 7 c and/or C 16 : 1 ω 6 c ), and C 14 : 0 . Phosphatidylethanolamine, phosphatidylglycerol, and diphosphatidylglycerol were major polar lipids in both strains. Strains G1-22 T and G1-23 T had DNA G+C contents of 40.2 and 38.9 mol%, respectively. Phylogenetic analyses based on 16S rRNA and genome sequences revealed that strains G1-22 T and G1-23 T formed distinct phylogenetic lineages within the genera Psychrosphaera and Paraglaciecola , respectively. Strain G1-22 T showed closest relatedness to Psychrosphaera ytuae MTZ26 T with 97.8% 16S rRNA gene sequence similarity, 70.2% average nucleotide identity (ANI), and a 21.5% digital DNA-DNA hybridization (dDDH) value, while strain G1-23 T was most closely related to Paraglaciecola aquimarina KCTC 32108 T with 95.6% 16S rRNA gene sequence similarity, 74.6% ANI, and a 20.1% dDDH value. Based on phenotypic and molecular characteristics, strains G1-22 T and G1-23 T are proposed to represent two novel species, namely Psychrosphaera algicola sp. nov. (type strain G1-22 T =KACC 22486 T =JCM 34971 T ) and Paraglaciecola algarum sp. nov. (type strain G1-23 T =KACC 22490 T =JCM 34972 T ), respectively. Additionally, based on the comparison of whole genome sequences, it is proposed that Pseudoalteromonas elyakovii , Pseudoalteromonas flavipulchra , and Pseudoalteromonas profundi are reclassified as later heterotypic synonyms of Pseudoalteromonas distincta , Pseudoalteromonas maricaloris , and Pseudoalteromonas gelatinilytica , respectively.

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 . 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 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.

Two Gram-stain-negative, rod-shaped, non-motile, aerobic and carotenoid-producing strains, belonging to the family Erythrobacteraceae, designated as H149 T and Z2 T , were isolated from tidal flat sediment samples collected in Hainan and Zhejiang, PR China, respectively. Growth of strain H149 T occurred at 15-42 °C, 0-10.0 % (w/v) NaCl, and pH 6.0-8.5, with the optima at 35-37 °C, 3.0-3.5 % (w/v) NaCl and pH 7.0. Strain Z2 T grew at 15-37 °C, 0-6.0 % (w/v) NaCl, and pH 6.0-9.5, with the optima at 25-30 °C, 0.5-1.0 % (w/v) NaCl and pH 6.0-6.5. Ubiquinone-10 was the sole ubiquinone in two strains. The predominant cellular fatty acids of strain H149 T were C 16 : 0 , summed feature 3 and summed feature 8, while those of strain Z2 T were C 17 : 1  ω 6 c , summed feature 3 and summed feature 8. Strains H149 T and Z2 T shared diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and sphingoglycolipid as major polar lipids. The 16S rRNA gene sequence identity analysis indicated that strain H149 T had the highest sequence identity of 98.4 % with Aurantiacibacter odishensis KCTC 23981 T , and strain Z2 T had that of 98.2 % with Qipengyuania pacifica NZ-96 T . Phylogenetic trees based on 16S rRNA gene and core-genome sequences revealed that strains H149 T and Z2 T formed two independent clades in the genera Aurantiacibacter and Qipengyuania , respectively. Strain H149 T had average nucleotide identity values of 74.0-81.3 % and in silico DNA-DNA hybridization values of 18.5-23.1 % with Aurantiacibacter type strains, while strain Z2 T had values of 73.3-78.7 % and 14.5-33.3 % with Qipengyuania type strains. The genomic DNA G+C contents of strains H149 T and Z2 T were 64.3 and 61.8 %, respectively. Based on the genetic, genomic, phylogenetic, physiological and chemotaxonomic results, strains H149 T (=KCTC 8397 T =MCCC 1K08920 T ) and Z2 T (=KCTC 8396 T =MCCC 1K08946 T ) are concluded to represent two novel Erythrobacteraceae species for which the names Aurantiacibacter hainanensis sp. nov. and Qipengyuania zhejiangensis sp. nov. are proposed, respectively.

A comprehensive polyphasic taxonomic investigation integrating taxongenomic criteria was conducted on strain IRAMC:0171 T isolated from the root nodules of Retama raetam in Tunisia. This Gram-stain-negative and aerobic bacterium thrived within a temperature range of 5-45 °C, optimal at 28 °C, and tolerated salt concentrations from 0-6 % NaCl, with an optimal range of 0-3 %. It displayed pH tolerance from pH 4 to 10, thriving best at pH 6.8-7.5. Chemotaxonomically, strain IRAMC:0171 T was characterized by diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, and phosphatidylethanolamine as polar lipids. Its predominant fatty acid composition was C 18 : 1 7c (61.2 %), and the primary ubiquinone was Q10 (97 %). Analysis of the 16S rRNA gene of strain IRAMC:0171  ω 7c (61.2 %), and the primary ubiquinone was Q10 (97 %). Analysis of the 16S rRNA gene of strain IRAMC:0171 T showed 99.08 % similarity to Mesorhizobium waimense ICMP 19557 T , Mesorhizobium amorphae ACCC 19665 T , and Mesorhizobium huakuii IAM 14158. However, digital DNA-DNA hybridization and average nucleotide identity analyses revealed values ranging from 21.1 to 25.2 % and 77.05 to 82.24 %, respectively, signifying significant deviation from established species demarcation thresholds. Phylogenetic studies, encompassing 16S rRNA, whole-genome-based tree reconstruction, and core protein analysis, positioned strain IRAMC:0171 T closest to Mesorhizobium terrae KCTC 72278 T and ' Mesorhizobium hungaricum ' UASWS1009 T , forming together a distinct branch within the genus Mesorhizobium . In consideration of this comprehensive data, we propose strain IRAMC:0171 T (=DSM 112841 T =CECT 30767 T ) as the type strain of a new species named Mesorhizobium retamae sp. nov.

A Gram-negative, ellipsoidal to short-rod-shaped, motile bacterium was isolated from Beijing's urban air. The isolate exhibited the closest kinship with Noviherbaspirillum aerium 122213-3 T , exhibiting 98.4 % 16S rRNA gene sequence similarity. Phylogenetic analyses based on 16S rRNA gene sequences and genomes showed that it clustered closely with N. aerium 122213-3 T , thus forming a distinct phylogenetic lineage within the genus Noviherbaspirillum . The average nucleotide identity and digital DNA-DNA hybridization values between strain I16B-00201 T and N. aerium 122213-3 T were 84.6 and 29.4 %, respectively. The respiratory ubiquinone was ubiquinone 8. The major fatty acids (>10 %) were summed feature 3 (C 16:1 ω6 c /C 16:1 ω7 c , 43.3 %), summed feature 8 (C 18:1 ω7 c /C 18:1 ω6 c , 15.9 %) and C 12:0 (11.0 %). The polyamine profile showed putrescine as the predominant compound. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, unknown lipids and unknown phosphatidylaminolipids. The phenotypic, phylogenetic and chemotaxonomic results consistently supported that strain I16B-00201 T represented a novel species of the genus Noviherbaspirillum , for which the name Noviherbaspirillum album sp. nov. is proposed, with I16B-00201 T (=CPCC 100848 T =KCTC 52095 T ) designated as the type strain. Its DNA G+C content is 59.4 mol%. Pan-genome analysis indicated that some Noviherbaspirillum species possess diverse nitrogen and aromatic compound metabolism pathways, suggesting their potential value in pollutant treatment.

A Gram-negative, non-motile, and creamy-white coloured bacterium, designated CAU 1616 T , was isolated from sea sand collected at Ayajin Beach, Goseong-gun, Republic of Korea. The bacterium was found to grow optimally at 37 °C, pH 8.0-8.5, and with 1-5 % (w/v) NaCl. Phylogenetic analyses based on the 16S rRNA gene sequences placed strain CAU 1616 T within the order Rhodospirillales . The highest 16S rRNA gene sequence similarity was to Fodinicurvata fenggangensis YIM D812 T (94.1 %), Fodinicurvata sediminis YIM D82 T (93.7 %), Fodinicurvata halophila BA45AL T (93.6 %) and Algihabitans albus HHTR 118 T (92.3 %). Comparing strain CAU 1616 T with closely related species ( Fodinicurvata fenggangensis YIM D812 T and Fodinicurvata sediminis YIM D82 T ), the average nucleotide identity based on blast+ values were 69.7-69.8 %, the average amino acid identity values were 61.3-61.4 %, and the digital DNA-DNA hybridization values were 18.4-18.5 %. The assembled draft genome of strain CAU 1616 T had 29 contigs with an N50 value of 385.8 kbp, a total length of 3 490 371 bp, and a DNA G+C content of 65.1 mol%. The predominant cellular fatty acids were C 18 : 1 2-OH, C 19 : 0 cyclo ω 8 c , and summed feature 8 (C 18 : 1  ω 6 c and/or C 18 : 1  ω 7 c ). The major respiratory quinone was Q-10. Based on phenotypic, phylogenetic, and chemotaxonomic evidence, strain CAU 1616 T represents a novel genus in the family Rhodovibrionaceae , for which the name Aquibaculum arenosum gen. nov., sp. nov. is proposed. The type strain is CAU 1616 T (=KCTC 82428 T =MCCC 1K06089 T ).

Bacterial strain H4R21 T was isolated from beech rhizosphere soil sampled in the forest experimental site of Montiers (Meuse, France). It effectively weathers minerals, hydrolyses chitin and produces quorum sensing signal molecules. The strain is aerobic and Gram-stain-negative. Phylogenetic analysis based on its 16S rRNA gene sequence indicated that strain H4R21 T belongs to the genus Collimonas with high sequence similarity to C. arenae Ter10 T (99.38 %), C. fungivorans Ter6 T (98.97 %), C. pratensis Ter91 T (98.76 %), C. humicola RLT1W51 T (98.46 %) and C. silvisoli RXD178 T (98.46 %), but less than 98 % similarity to other strains of the genus Collimonas . The predominant quinone in H4R21 T is ubiquinone-8 (Q8). The major polar lipids are diphosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol and lipid. The major fatty acids identified were C 12 : 0 , C 12:0 3-OH, C 16  :  0 and C 17:0  cyclo. The digital DNA G+C content of the genomic DNA was 59.5 mol%. Furthermore, the strain could be clearly distinguished from its closely related type strains by a combination of phylogenomic and in silico DNA-DNA hybridization results, and phenotypic characteristics. Therefore, strain H4R21 T represents a novel species within the genus Collimonas , for which the name Collimonas rhizosphaerae sp. nov. is proposed, with strain H4R21 T (=CFBP 9203 T =DSM 117599 T ) as the type strain.

A bacterial strain, designated S6 T , was isolated from the sandy soil on a rocky mountain in South China. Cells of S6 T were Gram-stain-negative, aerobic, non-spore-forming, non-motile and non-prosthecae-producing. 16S rRNA gene sequence analysis revealed the highest similarities to 12 uncultured bacteria, followed by Phenylobacterium sp. B6.10-61 (97.14 %). The closest related validly published strains are Caulobacter henricii ATCC 15253 T (96.15 %), Phenylobacterium conjunctum FWC 21 T (96.08 %) and Caulobacter mirabilis FWC 38 T (96.08 %). Phylogenetic analysis based on 16S rRNA gene, genome and proteome sequences demonstrated that S6 T formed a separated lineage in the genus Phenylobacterium . Strain S6 T contained Q-10 (97.5 %) as the major ubiquinone and C 18 : 1  ω7 c and C 16 : 0 as the major fatty acids. The polar lipid profile consisted of phosphatidylglycerol, an unknown phosphoglycolipid and three unknown glycolipids. The assembled genome comprises a chromosome with a length of 5.5 Mb and a plasmid of 96 014 bp. The G+C content was 67.6 mol%. The morphological, physiological, chemotaxonomic and phylogenetic analyses clearly distinguished this strain from its closest phylogenetic neighbours. Thus it is proposed that strain S6 T represents a novel species in the genus Phenylobacterium , for which the name Phenylobacterium montanum sp. nov. is proposed. The type strain is S6 T (=NBRC 115419 T =GCMCC 1.18594 T ).

A novel Gram-stain-negative strain, designated JM10B15 T , was isolated from pond water for Litopenaeus vannamei collected from Jiangmen City, Guangdong province, south PR China. Cells of the strain were aerobic, rod-shaped, and motile by lateral flagella. JM10B15 T could grow at 15-40 °C, pH 6.0-9.5, and in 0-3.0 % NaCl, with optimal growth at 25-35 °C, pH 7.5-8.5, and in 0 % NaCl, respectively. Furthermore, this strain grew well on Reasoner's 2A agar but not on nutrient broth agar or Luria-Bertani agar. JM10B15 T was a denitrifying bacterium capable of removing nitrites and nitrates, and three key functional genes, nasA , nirS , and nosZ , were identified in its genome. The results of phylogenetic analyses based on the 16S rRNA gene and genome sequences indicated that JM10B15 T belonged to the genus Gemmobacter . JM10B15 T showed the highest 16S rRNA sequence similarity to Gemmobacter lutimaris YJ-T1-11 T (98.8 %), followed by Gemmobacter aquatilis IFAM 1031 T (98.6 %) and Gemmobacter serpentinus HB-1 T (98.1 %). The average nucleotide identity and digital DNA-DNA hybridization values between JM10B15 T and the other type strains of genus Gemmobacter were 78.1-82.1 % and 18.4-22.1 %, respectively. The major fatty acids of strain JM10B15 T were summed feature 8 (C 18 : 1  ω 6 c and/or C 18 : 1  ω 7 c ) and C 18 : 1  ω 7 c 11-methyl. In addition, the major respiratory quinone of this novel strain was Q-10, and the predominant polar lipids were phosphatidylglycerol, phosphatidylethanolamine, four unidentified phospholipids, three unidentified lipids, and an unidentified aminophospholipid. Results of analyses of the phylogenetic, genomic, physiological, and biochemical characteristics indicated that JM10B15 T represents a novel species of the genus Gemmobacter , for which the name Gemmobacter denitrificans sp. nov. is proposed. The type strain is JM10B15 T (=GDMCC 1.4148 T =KCTC 8140 T ).

A Gram-negative, aerobic, pink-pigmented, and bacteriochlorophyll a -containing bacterial strain, designated B14 T , was isolated from the macroalga Fucus spiralis sampled from the southern North Sea, Germany. Based on 16S rRNA gene sequences, species of the genera Roseobacter and Sulfitobacter were most closely related to strain B14 T with sequence identities ranging from 98.15 % ( Roseobacter denitrificans Och 114 T ) to 99.11 % ( Roseobacter litoralis Och 149 T ), whereas Sulfitobacter mediterraneus CH-B427 T exhibited 98.52 % sequence identity. Digital DNA-DNA hybridization and average nucleotide identity values between the genome of the novel strain and that of closely related Roseobacter and Sulfitobacter type strains were <20 % and <77 %, respectively. The novel strain contained ubiquinone-10 as the only respiratory quinone and C 18 : 1  ω7 c , C 16 : 0 , C 18 : 0 , C 12 : 1  ω7 c , C 18 : 2  ω7,13 c , and C 10 : 0 3-OH as the major cellular fatty acids. The predominant polar lipids of strain B14 T were phosphatidylcholine, phosphatidylethanolamine, and phosphatidylglycerol. The genome of strain B14 T comprises a chromosome with a size of 4.5 Mbp, one chromid, and four plasmids. The genome contains the complete gene cluster for aerobic anoxygenic photosynthesis required for a photoheterotrophic lifestyle. The results of this study indicate that strain B14 T (=DSM 116946 T =LMG 33352 T ) represents a novel species of the genus Roseobacter for which the name Roseobacter fucihabitans sp. nov. is proposed.

Strain S30A2 T , isolated from the acid mine drainage sediment of Mengzi Copper Mine, Yunnan, is proposed to represent a novel species of the sulphur-oxidizing genus Acidithiobacillus . Cells were Gram-stain-negative, non-endospore forming, highly motile with one or two monopolar flagella and rod-shaped. The strain was mesophilic, growing at 30-50 °C (optimum, 38 °C), acidophilic, growing at pH 2.0-4.5 (optimum, pH 2.5), and tolerant of 0-4 % (w/v; 684 mol l -1 ) NaCl. The 16S rRNA gene-based sequence analysis showed that strain S30A2 T belongs to the genus Acidithiobacillus and shows the largest similarity of 96.6 % to the type strain Acidithiobacillus caldus KU T . The genomic DNA G+C content of strain S30A2 T was 59.25 mol%. The average nucleotide identity ANIb and ANIm values between strain S30A2 T and A. caldus KU T were 70.95 and 89.78 %, respectively and the digital DNA-DNA hybridization value was 24.9 %. Strain S30A2 T was strictly aerobic and could utilize elementary sulphur and tetrathionate to support chemolithotrophic growth. The major cellular fatty acid of S30A2 T was C 19 : 1 ω7 c . The respiratory quinones were ubiquinone-8 and ubiquinone-7. Based upon its phylogenetic, genetic, phenotypic, physiologic and chemotaxonomic characteristics, strain S30A2 T is considered to represent a novel species of the genus Acidithiobacillus , for which the name Acidithiobacillus acidisediminis sp. nov. is proposed. The type strain is S30A2 T (=CGMCC 1.17059 T =KCTC 72580 T ).

A Gram-negative, facultative anaerobic, non-motile and rod-shaped bacterium, designated 10c7w1 T , was isolated from a human gastrointestinal tract. Colonies on agar plates were small, circular, smooth and beige. The optimal growth conditions were determined to be 37 °C, pH 7.0-7.5 and 0 % (w/v) NaCl. Comparative analysis of complete 16S rRNA gene sequences revealed that strain 10c7w1 T showed the highest sequence similarity of 95.8 % to Ottowia beijingensis MCCC 1A01410 T , followed by Ottowia thiooxydans (95.2 %) JCM 11629 T . The average amino acid identity values between 10c7w1 T and O. beijingensis MCCC 1A01410 T and O. thiooxydans JCM 11629 T were above 60 % (71.4 and 69.5 %). The average nucleotide identity values between strain 10c7w1 T and O. beijingensis MCCC 1A01410 T and O. thiooxydans JCM 11629 T were 76.9 and 72.5 %, respectively. The dominant fatty acids (≥10 %) were straight chain ones, with summed feature 3 (C 16 : 1  ω 7 c /C 16 : 1  ω 6 c ), summed feature 8 (C 18 : 1  ω 7 c /C 18 : 1  ω 6 c ) and C 16 : 00 being the most abundant. Q-8 was the only respiratory quinone. The major polar lipids of strain 10c7w1 T were phosphatidylethanolamine, diphosphatidylglycerol and unknown lipids. The DNA G+C content of strain 10c7w1 T was 63.6 mol%. On the basis of phylogenetic, phenotypic and chemotaxonomic data, strain 10c7w1 T is considered to represent a novel species within the genus Ottowia , for which the name Ottowia cancrivicina sp. nov. is proposed. The type strain is 10c7w1 T (=MCCC 1H01399 T =KCTC 92200 T ).

Two strictly aerobic and rod-shaped bacteria, labelled as DB1703 T and DB2414S T , were obtained from an automobile air conditioning system. Strain DB1703 T was Gram-stain-negative, while strain DB2414S T was Gram-stain-positive. Both strains were catalase-positive and oxidase-negative. Strains DB1703 T and DB2414S T were able to grow at 18-42 °C. Strain DB1703 T grew within a NaCl range of 0-3 % and a pH range of 6.0-8.0; while strain DB2414S T grew at 0-1 % and pH 6.5-8.5. The phylogenetic and 16S rRNA gene sequence analysis indicated that strains DB1703 T and DB2414S T belonged to the genera Enterovirga and Knoellia , respectively. Strain DB1703 T showed the closest phylogenetic similarity to Enterovirga rhinocerotis YIM 100770 T (94.8 %), whereas strain DB2414S T was most closely related to Knoellia remsis ATCC BAA-1496 T (97.7 %). The genome sizes of strains DB1703 T and DB2414S T were 4 652 148 and 4 282 418 bp, respectively, with DNA G+C contents of 68.8 and 70.5 mol%, respectively. Chemotaxonomic data showed Q-10 as the sole ubiquinone in DB1703 T and ML-8 (H4) in DB2414S T . The predominant cellular fatty acid in DB1703 T was summed feature 8 (C 18 : 1  ω 7 c and/or C 18 : 1  ω 6 c ), whereas iso-C 16 : 0 , C 17 : 1  ω 8 c , and iso-C 15 : 0 were dominant in DB2414S T . Overall, the polyphasic taxonomic comparisons showed that strains DB1703 T and DB2414S T were distinct from their closest taxa and represent novel species within the genera Enterovirga and Knoellia , respectively. Accordingly, we propose the names Enterovirga aerilata sp. nov., with the type strain DB1703 T (=KCTC 72724 T =NBRC 114759 T ), and Knoellia koreensis sp. nov., with the type strain DB2414S T (=KCTC 49355 T =NBRC 114620 T ).

Four newly discovered Gram-stain-negative bacteria, designated as BL00010 T , BL00058, D8-11 T and BL00200, were isolated from water samples collected at three hydrological monitoring stations (namely Chiang Saen, Chiang Khan and Nong Khai) located along the Mekong River in Thailand. An investigation encompassing phenotypic, chemotaxonomic and genomic traits was conducted. The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that all four isolates represented members of the genus Rhodoferax . These isolates were closely related to Rhodoferax bucti KCTC 62564 T with a similarity of 99.59%. The major fatty acids of the four novel isolates included C 16:0 and C 16:1 ω7 c and/or C 16 : 1 ω6 c , whereas the major respiratory quinone was identified as ubiquinone Q-8. In addition, phosphatidylethanolamine was identified as a major polar lipid in these bacteria. The genomes of BL00010 T , BL00058, D8-11 T and BL00200 were similar in size (3.88-4.01 Mbp) and DNA G+C contents (59.5, 59.3, 59.5 and 59.3 mol%, respectively). In contrast to R. bucti KCTC 62564 T and Rhodoferax aquaticus KCTC 32394 T , the newly discovered species possessed several genes involved in nitrite and nitrile metabolism, which may be related to their unique adaptation to nitrile-rich environments. From the results of the pairwise analysis of average nucleotide identity of the whole genome and digital DNA-DNA hybridisation, it was evident that BL00010 T and D8-11 T represented two novel species, for which we propose the nomenclature Rhodoferax potami sp. nov., with the type strain BL00010 T (TBRC 17198 T = NBRC 116413 T ), and Rhodoferax mekongensis sp. nov., with the type strain D8-11 T (TBRC 17307 T = NBRC 116415 T ).

A Gram-stain-negative and rod-shaped bacterium, designated strain CY04 T , was isolated from a sediment sample collected from the Yellow Sea. CY04 T exhibited the highest 16S rRNA gene sequence similarity of 98.7 % to Zongyanglinia huanghaiensis CY05 T , followed by the similarities of 98.6 %, 98.0 and 98.0 % to Zongyanglinia marina DSW4-44 T , Parasedimentitalea marina W43 T and Parasedimentitalea psychrophila QS115 T respectively. Phylogenetic analysis based on 16S rRNA gene and phylogenomic analysis based on genome sequences revealed that CY04 T formed a robust cluster with Z. huanghaiensis CY05 T , Z. marina DSW4-44 T , P. marina W43 T and P. psychrophila QS115 T . Calculated digital DNA-DNA hybridisation and average nucleotide identity values between CY04 T and its closely related species were 22.2-23.7 % and 79.0-81.2 % respectively. Cells of CY04 T were strictly aerobic, non-motile and positive for catalase, oxidase and denitrification. CY04 T harboured a set of genes encoding the enzymes involved in denitrification. Growth occurred at 10-30 °C (optimum, 20 °C), at pH 6.5-9.5 (optimum, pH 8.0) and with 1-6 % (w/v) (optimum, 2.5 %,) NaCl. The major component of the fatty acids was summed feature 8 (C 18 : 1 ω7 c and/or C 18 : 1 ω6 c ). The isoprenoid quinone was Q-10. Results of the phenotypic, chemotaxonomic and molecular study indicate that strain CY04 T represents a novel species of the genus Parasedimentitalea , for which the name Parasedimentitalea denitrificans sp. nov. is proposed. The type strain is CY04 T (=MCCC 1K08635 T =KCTC 62199 T ). It is also proposed that Zongyanglinia huanghaiensis and Zongyanglinia marina should be reclassified as Parasedimentitalea huanghaiensis comb. nov. and Parasedimentitalea maritima nom. nov. An emended description of the genus Parasedimentitalea is also proposed.

Two Gram-stain-negative, facultatively aerobic, and motile rod bacteria, designated as strains KJ51-3 T and 15G1-11 T , were isolated from marine algae collected in the Republic of Korea. Both strains exhibited catalase- and oxidase-positive activities. Optimum growth conditions for strain KJ51-3 T were observed at 30 °C and pH 6.0-8.0, with 1.0-7.0 % (w/v) NaCl, whereas strain 15G1-11 T exhibited optimal growth at 30 °C, pH 7.0, and 1.0-5.0 % NaCl. Major fatty acids detected in both strains included C 16 : 0 , C 10 : 0 3-OH and summed features 3 (C 16 : 1  ω 7 c and/or C 16 : 1  ω 6 c ) and 8 (C 18 : 1  ω 7 c and/or C 18 : 1 had PE, PG, and an unidentified aminolipid. Ubiquinone-8 was the predominant respiratory quinone in both strains, with minor detection of ubiquinone-9 in strain KJ51-3  ω 6 c ). As for polar lipids, strain KJ51-3 T contained phosphatidylethanolamine (PE), phosphatidylglycerol (PG), diphosphatidylglycerol, and two unidentified phospholipids, whereas strain 15G1-11 T had PE, PG, and an unidentified aminolipid. Ubiquinone-8 was the predominant respiratory quinone in both strains, with minor detection of ubiquinone-9 in strain KJ51-3 T . The genomic DNA G+C contents were 44.0 mol% for strain KJ51-3 T and 40.5 mol% for strain 15G1-11 T . Phylogenetic analyses based on both 16S rRNA gene and genome sequences placed strains KJ51-3 T and 15G1-11 T into distinct lineages within the genus Marinomonas , most closely related to Marinomonas arctica 328 T (98.6 %) and Marinomonas algicola SM1966 T (98.3 %), respectively. Strains KJ51-3 T and 15G1-11 T exhibited a 94.6 % 16S rRNA gene sequence similarity and a 70.7 % average nucleotide identity (ANI), with ANI values of 91.9 and 79.3 % between them and M. arctica 328 T and M. algicola SM1966 T , respectively, indicating that they represent novel species. In summary, based on their phenotypic, chemotaxonomic, and phylogenetic properties, strains KJ51-3 T and 15G1-11 T are proposed to represent novel species within the genus Marinomonas , for which the names Marinomonas rhodophyticola sp. nov. (KJ51-3 T =KACC 22756 T =JCM 35591 T ) and Marinomonas phaeophyticola sp. nov. (15G1-11 T =KACC 22593 T =JCM 35412 T ) are respectively proposed.

The use of algae as feedstock for industrial purposes, such as in bioethanol production, is desirable. During a search for new agarolytic marine bacteria, a novel Gram-stain-negative, strictly aerobic, and agarolytic bacterium, designated as TS8 T , was isolated from algae in the harbour of the island of Susak, Croatia. The cells were rod-shaped and motile. The G+C content of the sequenced genome was 38.6 mol%. Growth was observed at 11-37 °C, with 0.5-13 % (w/v) NaCl, and at pH 6.0-9.0. The main fatty acids were summed feature 3 (C 16 : 1  ω 6 c and/or C 16 : 1  ω 7 c ), summed feature 8 (C 18 : 1  ω 7 c . The main respiratory quinone was ubiquinone-8. The major polar lipids were phosphatidylethanolamine and phosphatidylglycerol. Analysis of 16S rRNA gene sequences indicated that the newly isolated strain belongs to the genus 18 : 1  ω 6 c ), and C 16 : 0 . The main respiratory quinone was ubiquinone-8. The major polar lipids were phosphatidylethanolamine and phosphatidylglycerol. Analysis of 16S rRNA gene sequences indicated that the newly isolated strain belongs to the genus Catenovulum . Based on 16S rRNA gene sequence data, strain TS8 T is closely related to Catenovulum sediminis D2 T (95.7 %), Catenovulum agarivorans YM01 T (95.0 %), and Catenovulum maritimum Q1 T (93.2 %). Digital DNA-DNA hybridization values between TS8 T and the other Catenovulum strains were below 25 %. Based on genotypic, phenotypic, and phylogenetic data, strain TS8 T represents a new species of the genus Catenovulum , for which the name Catenovulum adriaticum sp. nov. is proposed. The type strain is TS8 T (=DSM 114830 T =NCIMB 15451 T ).

Two Gram-negative bacterial strains designated MMS20-SJTN17 T and MMS20-SJTR3 T were isolated from a grassland soil sample, and taxonomically characterized using a polyphasic approach. The 16S rRNA gene sequence analysis indicates that both strains belong to the genus Paraburkholderia of the class Betaproteobacteria , with strain MMS20-SJTN17 T being mostly related to Paraburkholderia sprentiae WSM5005 T (96.45 % sequence similarity) and strain MMS20-SJTR3 T to Paraburkholderia tuberum STM678 T (98.59 % sequence similarity). MMS20-SJTN17 T could grow at 15-40 °C (optimum, 25-30 °C) and at pH 6.0-8.0 (optimum, pH 6.0-7.0), whereas MMS20-SJTR3 T could grow at 10-40 °C (optimum, 30-37 °C) and at pH 6.0-8.0 (optimum, pH 6.0). Both strains tolerated up to 1 % (w/v) NaCl (optimum, 0 %). The major fatty acids of MMS20-SJTN17 T were C 16 : 0 and C 19 : 0 cyclo ω8 c , and those of MMS20-SJTR3 T were C 17 : 0 cyclo and a summed feature comprising C 18 : 1  ω7 c and/or C 18 : 1  ω6 c . The major isoprenoid quinone of both strains was ubiquinone-8 and the diagnostic polar lipids were diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. Regarding plant growth promoting potential, both strains were capable of producing indole acetic acid, siderophore and 1-aminocyclopropane-1-carboxylic acid deaminase, and also showed phosphate-solubilizing activity. A genome-based comparison using orthologous average nucleotide identity and digital DNA-DNA hybridization values indicates that strain MMS20-SJTN17 T shares highest relatedness with Paraburkholderia monticola JC2948 T and MMS20-SJTR3 T with Paraburkholderia antibiotica G-4-1-8 T , with values clearly below the cutoffs for species distinction. Examination of biosynthetic gene clusters responsible for secondary metabolite production reveals unique characteristics distinguishing each strain from closely related Paraburkholderia species. On the basis of genotypic, phenotypic, chemotaxonomic and phylogenomic data, each strain should be classified as a novel species of the genus Paraburkholderia , for which the names Paraburkholderia translucens sp. nov. (=MMS20-SJTN17 T =LMG 32366 T =KCTC 82783 T ) and Paraburkholderia sejongensis sp. nov. (=MMS20-SJTR3 T =LMG 32367 T =KCTC 82784 T ) are proposed.

A Gram-stain-negative, aerobic, oxidase-positive, weakly catalase-positive, motile by means of a single polar flagellum, rod-shaped bacterium designated as strain S2-9 T was isolated from sediment sampled in Wiyang pond, Republic of Korea. Growth of this strain was observed at 10-40 °C (optimum, 35 °C) and pH 5.5-9.5 (optimum, pH 7.0-8.0) and in the presence of 0-0.5 % NaCl in Reasoner's 2A broth. The major fatty acids (>10 %) of strain S2-9 T were C 16 : 0 and summed feature 3 (comprising a mixture of C 16 : 1  ω 7 c and/or C 16 : 1 ). Ubiquinone-8 was detected as the respiratory quinone. The major polar lipids were phosphatidylethanolamine and phosphatidylglycerol. Strain S2-9  ω 6 c ). Ubiquinone-8 was detected as the respiratory quinone. The major polar lipids were phosphatidylethanolamine and phosphatidylglycerol. Strain S2-9 T showed the highest 16S rRNA gene sequence similarity to Paucibacter oligotrophus CHU3 T (98.7 %), followed by ' Paucibacter aquatile ' CR182 (98.4 %), all type strains of Pelomonas species (98.1-98.3 %), Mitsuaria chitosanitabida NBRC 102408 T (97.9 %), Kinneretia asaccharophila KIN192 T (97.8 %), Mitsuaria chitinivorans HWN-4 T (97.4 %), and Paucibacter toxinivorans 2C20 T (97.4 %). Phylogenetic trees based on the 16S rRNA gene and whole-genome sequences showed that strain S2-9 T formed a tight phylogenetic lineage with Paucibacter species (CHU3 T , CR182, and 2C20 T ). Average nucleotide identity and digital DNA-DNA hybridization values between strain S2-9 T and Paucibacter strains were 76.6-79.3% and 19.5-21.5 %, respectively. The genomic DNA G+C content of strain S2-9 T was 68.3 mol%. Notably, genes responsible for both sulphur oxidation and reduction and denitrification were found in the genome of strain S2-9 T , suggesting that strain S2-9 T is involved in the nitrogen and sulphur cycles in pond ecosystems. Based on the polyphasic taxonomic results, strain S2-9 T represents a novel species of the genus Paucibacter , for which the name Paucibacter sediminis sp. nov. is proposed. The type strain is S2-9 T (= KACC 22267 T = JCM 34541 T ).

Two Gram-negative, aerobic, rod-shaped bacterial strains, 7MK25 T and 6Y81 T , were isolated from forest soil of Dinghushan Biosphere Reserve, Guangdong Province, PR China. Based on the results of 16S rRNA gene sequence analysis, strain 7MK25 T showed the highest similarity (93.6 %) to Methyloferula stellata AR4 T , followed by Bosea thiooxidans DSM 9653 T (93.3 %). Strain 6Y81 T had the highest similarity of 97.9 % to Lichenibacterium minor RmlP026 T , followed by Lichenibacterium ramalinae RmlP001 T (97.2 %). Phylogenomic analysis using the UBCG and PhyloPhlAn methods consistently showed that strain 7MK25 T formed a sister clade to Boseaceae , while strain 6Y81 T formed an independent clade within the genus Lichenibacterium , both in the order Hyphomicrobiales . The digital DNA-DNA hybridization and average nucleotide identity values between strains 7MK25 T , 6Y81 T and their close relatives were in the ranges of 19.1-29.9 % and 72.5-85.5 %, respectively. The major fatty acids of 7MK25 T were summed feature 8 (C 18 : 1  ω7 c /C 18 : 1  ω6 c ), C 19 : 0 cyclo ω8 c , C 16 : 0 and C 17 : 0 cyclo, while those of 6Y81 T were summed feature 8 (C 18 : 1  ω7 c /C 18 : 1  ω6 c ), C 16 : 0 and C 16 : 0 3-OH. Strains 7MK25 T and 6Y81 T took diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine as their dominant polar lipids, and Q-10 as their major respiratory quinone. On the basis of phenotypic and phylogenetic data, strain 7MK25 T is proposed to represent a novel species of a novel genus with name Terrirubrum flagellatum gen. nov., sp. nov., within a novel family Terrirubraceae fam. nov., with 7MK25 T (=KCTC 62738 T =GDMCC 1.1452 T ) as its type strain. Strain 6Y81 T represents a novel species in the genus Lichenibacterium , for which the name Lichenibacterium dinghuense sp. nov. (type strain 6Y81 T =KACC 21 727 T =GDMCC 1.2176 T ) is proposed. Rhodoblastaceae fam. nov. with Rhodoblastus as the type genus is also proposed to solve the non-monophylectic problem of the family Roseiarcaceae .

Two Gram-stain-negative, chemoheterotrophic, aerobic bacteria, designated IC7 T and JM2-8 T , were isolated from seawater of the Yellow Sea of China and rhizosphere soil of mangroves in Xiamen, Fujian, respectively. Phylogenetic analyses based on 16S rRNA gene and genome sequences showed that these two novel strains belonged to the family Roseobacteraceae . Strain IC7 T formed a coherent lineage within the genus Pseudodonghicola , showing 98.05 % 16S rRNA gene sequence similarity to Pseudodonghicola xiamenensis Y-2 T . Strain JM2-8 T was most closely related to members of the genus Sedimentitalea , showing 96.51 and 96.73 % 16S rRNA gene sequence similarities to Sedimentitalea nanhaiensis NH52F T and Sedimentitalea todarodis KHS03 T , respectively. The two novel strains contained Q-10 as the major quinone, and phosphatidylethanolamine, aminophospholipid, phosphatidylglycerol and phosphatidylcholine as the principal polar lipids. The main fatty acid of strain IC7 T was C 19 : 0 cyclo ω 8 c , while the fatty acid profile JM2-8 T was dominated by summed feature 8 containing C 18 : 1  ω 7 c and/or C 18 : 1  ω 6 c . The average nucleotide identity and digital DNA-DNA hybridization values between these two novel isolates and their closely related species were below the cut-off values of 95-96 and 70 %, respectively. The combined genotypic and phenotypic data show that strain IC7 T represents a novel species of the genus Pseudodonghicola , for which the name Pseudodonghicola flavimaris sp. nov. is proposed, with the type strain IC7 T (=MCCC 1A02763 T =KCTC 82844 T ), and strain JM2-8 T represents a novel species of the genus Sedimentitalea , for which the name Sedimentitalea xiamensis sp. nov. is proposed, with the type strain JM2-8 T (=MCCC 1A17756 T =KCTC 82846 T ).

A diatom-associated bacterium, designated as strain F10 T , was isolated from a pure culture of the pennate diatom Asterionellopsis glacialis A3 and has since been used to characterize molecular mechanisms of symbiosis between phytoplankton and bacteria, including interactions using diatom-derived azelaic acid. Its origin from a hypersaline environment, combined with its capacity for quorum sensing, biofilm formation, and potential for dimethylsulfoniopropionate methylation/cleavage, suggest it is within the family Roseobacteraceae . Initial phylogenetic analysis of the 16S rRNA gene sequence placed this isolate within the Phaeobacter genus, but recent genomic and phylogenomic analyses show strain F10 T is a separate lineage diverging from the genus Pseudophaeobacter . The genomic DNA G+C content is 60.0 mol%. The predominant respiratory quinone is Q-10. The major fatty acids are C 18 : 1  ω7 c and C 16 : 0 . Strain F10 T also contains C 10 : 0 3-OH and the furan-containing fatty acid 10,13-epoxy-11-methyl-octadecadienoate (9-(3-methyl-5-pentylfuran-2-yl)nonanoic acid). The major polar lipids are diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. Based on genomic, phylogenomic, phenotypic and chemotaxonomic characterizations, strain F10 T represents a novel genus and species with the proposed name, Phycobacter azelaicus gen. nov. sp. nov. The type strain is F10 T (=NCMA B37 T =NCIMB 15470 T =NRIC 2002 T ).

A novel bacterial strain, N1Y112 T , was isolated from coastal sediment collected in Weihai, PR China. This Gram-stain-negative, facultatively anaerobic, motile rod-shaped bacterium exhibited the ability to oxidize thiosulphate to sulphate and reduce nitrate to ammonia through its Sox system and nitrate reduction pathway, respectively. The strain grew at 20-35 °C (optimum, 28 °C), pH 6.0-10.0 (optimum, pH 7.5) and in the presence of 1.0-5.0 % (w/v) NaCl (optimum, 3.0 %). Major fatty acids present in the strain included summed feature 8 (comprising C 18 : 1  ω 7 c and/or C 18 : 1  ω 6 c ), summed feature 3 (comprising C 16 : 1  ω 7 c and/or C 16 : 1 contained ubiquinone-7 and ubiquinone-8 as isoprenoid quinones, with a genomic G+C content of 50.6 mol%. Based on phylogenetic analysis, strain N1Y112  ω 6 c ) and C 16 : 0 . Its polar lipid profile consisted of one phosphatidylethanolamine, two unknown aminolipids, one aminophosphoglycolipid, one diphosphatidylglycerol, one phosphatidylglycerol, two unknown phospholipids and two unknown lipids. Strain N1Y112 T contained ubiquinone-7 and ubiquinone-8 as isoprenoid quinones, with a genomic G+C content of 50.6 mol%. Based on phylogenetic analysis, strain N1Y112 T clustered with Pontibacterium granulatum JCM 30316 T being its closest relative at 97.1 % 16S rRNA gene sequence similarity. The average nucleotide identity and digital DNA-DNA hybridization values were 77.1 and 20.7 %, respectively, which suggest significant differences between genomes of N1Y112 T and P. granulatum JCM 30316 T . Based on the findings from its phenotypic, genotypic and phylogenetic analyses, N1Y112 T is considered to represent a novel species of the genus Pontibacterium , for which the name Pontibacterium sinense sp. nov. is proposed. The type strain is N1Y112 T (=KCTC 72927 T =MCCC 1H00429 T ).

Three Gram-stain-negative, aerobic, rod-shaped, stalked and motile strains with a polar flagellum (BYS171W T , DXS10W T and LKC15W T ) were isolated from streams in PR China. Comparisons based on 16S rRNA gene sequences showed that strains BYS171W T and DXS10W T had the highest 16S rRNA gene sequence similarities (98.1 and 98.6 %, respectively) to Asticcacaulis excentricus CB 48 T , and strain LKC15W T showed 99.6 % similarity to Asticcacaulis endophyticus ZFGT-14 T . These three strains showed 16S rRNA gene sequence similarities of less than 96.9 % to other species of the genus Asticcacaulis . A phylogenetic tree reconstructed based on 16S rRNA gene sequences also showed that strains BYS171W T and DXS10W T took A. excentricus CB 48 T as their closest neighbour, and strain LKC15W T formed a tight cluster with A. endophyticus ZFGT-14 T . The phylogenomic tree also showed that these three strains belong to the genus Asticcacaulis and form a distinct clade with the species of the genus Asticcacaulis . The major cellular fatty acids of these three strains were summed feature 3 (C 16 : 1  ω 7 c and/or C 16 : 1  ω 6 c ), summed feature 8 (C 18 : 1  ω 7 c and/or C 18 : 1  ω 6 c ), C 16 : 0 and 11-methyl C 18 : 1  ω 7 c . Their polar lipids mainly consisted of phosphatidylglycerol, unidentified glycolipids and nitrogen-containing phosphoglycolipids. The calculated OrthoANIu and digital DNA-DNA hybridization values among strains BYS171W T , DXS10W T , LKC15W T and other related strains were less than 87.2 % and 34.0 %, respectively, indicating that these three strains should represent three independent novel species of the genus Asticcacaulis , for which the names Asticcacaulis aquaticus sp. nov. (type strain BYS171W T =GDMCC 1.3226 T =KCTC 92612 T ), Asticcacaulis currens sp. nov. (type strain DXS10W T =GDMCC 1.3224 T =KCTC 92543 T ) and Asticcacaulis machinosus sp. nov. (type strain LKC15W T =GDMCC 1.3225 T =KCTC 92544 T ) are proposed.

A Gram-reaction-negative, aerobic, motile, rod-shaped bacterium, designated GH3-8 T , was isolated from rhizosphere mudflats of halophytes on the seashore of Gangwha Island, Republic of Korea. Growth was observed at pH 4-10 (optimum, pH 7-8), at 4-40 °C (optimum, 37 °C) and in the presence of 0.5-20 % (w/v) NaCl (optimum, 4 %). The predominant respiratory quinone was Q-9. The major fatty acids were C 18 : 1 ω7 c , C 16 : 0 , summed feature 3 (C 16 : 1 ω7 c and/or C 16 : 1 ω6 c ) and C 12 : 0 3OH. The polar lipids contained phosphatidylethanolamine, phosphatidylglycerol, an unidentified phosphoglycolipid, an unidentified phosphoglycoaminolipid, an unidentified glycoaminolipid, two unidentified phospholipids and two unidentified lipids. Phylogenetic analysis based on 16S rRNA gene sequences exhibited that the isolate belonged to the family Halomonadaceae , with the most closely related species, Larsenimonas suaedae (98.1 % sequence similarity) and Larsenimonas salina (97.9 %). Sequence similarity values between the isolate and other representatives of the family Halomonadaceae were all below 95.3 %. The values of average nucleotide identity between strain GH3-8 T and members of the genus Larsenimonas were 73.42 % with L. salina CCM 8464 T and 72.38 % with L. suaedae DSM 22428 T . Strain GH3-8 T showed digital DNA-DNA hybridization values of 18.5-18.6 % with members of the genus Larsenimonas . Based on phenotypic and chemotaxonomic distinctiveness together with low overall genomic relatedness indices and phylogenetic data, the isolate is considered to represent a new species of the genus Larsenimonas , for which the name Larsenimonas rhizosphaerae sp. nov. is proposed, with the type strain GH3-8 T (=KCTC 62127 T =NBRC 113214 T ).