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Coastal salinity typically alters the soil microbial communities, which subsequently affect the biogeochemical cycle of nutrients in the soil. The seasonal variation of the soil fungal communities in the coastal area, closely associated with plant population, is poorly understood. This study provides an insight into the fungal community's variations from autumn to winter and spring to summer at a well-populated area of salt-tolerant Tamarix chinensis and beach. The richness and diversity of fungal community were higher in the spring season and lower in the winter season, as showed by high throughput sequencing of the 18S rRNA gene. Ascomycota was the predominant phylum reported in all samples across the region, and higher difference was reported at order level across the seasonal variations. The redundancy analysis suggested that the abundance and diversity of fungal communities in different seasons are mainly correlated to total organic carbon and total nitrogen. Additionally, the saprotrophic and pathotrophic fungi decreased while symbiotic fungi increased in the autumn season. This study provides a pattern of seasonal variation in fungal community composition that further broadens our limited understanding of how the density of the salt-tolerant T. chinensis population of the coastal saline soil could respond to their seasonal variations. [ABSTRACT FROM AUTHOR]

• Zein, a biopolymer protein from corn, was used to construct the liquid chromatography stationary phase. • The PEI/Zein@SiO 2 column displayed good separation for hydrophilic/hydrophobic compounds. • Expanding the potential application of zein in the field of separation analysis. Based on the adhesion of polyethyleneimine (PEI), a novel PEI/zein co-modified core-shell stationary phase (PEI/Zein@SiO 2) was prepared by doping zein to form a composite modification layer. The stationary phase achieved effective separation of nucleosides, bases and antibiotics in hydrophilic interaction mode on account of the hydrophilic groups of composite coating. With the hydrophobicity of zein, the flavones could be separated in reversed-phase mode. In short, the separation and analysis of hydrophilic/hydrophobic compounds were accomplished excellently by the PEI/Zein@SiO 2 column with mixed double mode. The prepared chromatographic stationary phase not only avoided the dissolution of zein, but also covered the strong adsorption of some analytes caused by silica hydroxyl groups on the surface of silica spheres. The morphological structure and specific surface area of the material were reflected by various characterization techniques. Hydrophilic/hydrophobic compounds were used as tested analytes to research separation performance and retention mechanisms of PEI/Zein@SiO 2 column. The stability and reproducibility of the PEI/Zein@SiO 2 stationary phase were satisfied. Therefore, the modification of zein could improve the separation selectivity of stationary phase effectively for complex samples, which had the potential to be one of the significant potential application materials in stationary phase packing. [ABSTRACT FROM AUTHOR]

Limited knowledge about the variation patterns of bacterial community composition in the sand and vegetative ecosystems confines our understanding regarding the contribution of the sand dune to desert areas. In this study, 454 pyrosequencing platforms were adopted to determine the community structure of bacteria and diversity of sand dunes in northeastern Qinghai-Tibet Plateau, China: 50 cm deep, rhizosphere, physical crusts, and biological crusts representing sand and vegetative ecosystems, respectively. The findings revealed significant variation in bacterial diversities and the structure of communities in the sand and vegetative ecosystems. The dominant bacterial phyla of sand and vegetative ecosystems were Firmicutes (47%), Actinobacteria (21%), Proteobacteria (16%), and Bacteroidetes (13%), while Lactococcus (50%) was found to be the dominant genus. Furthermore, samples with high alpha-diversity indices (Chao 1 and Shannon) for the vegetative ecosystem have the lowest modularity index and the largest number of biomarkers, with some exceptions. Redundancy analysis exhibited that environmental factors could explain 72% (phyla) and 67% (genera) of the bacterial communities, with EC, TC, and TOC being the major driving factors. This study expands our understanding of bacterial community composition in the desert ecosystem. The findings suggest that variations in the sand and vegetative ecosystems, such as those predicted by environmental factors, may reduce the abundance and diversity of bacteria, a response that likely affects the provision of key ecosystem processes by desert regions. [ABSTRACT FROM AUTHOR]

• It is the best for strength and workability with 20% replacement of aeolian sand. • Influence mechanism of aeolian sand on strength of concrete is revealed. • Effect of aeolian sand on strength is due to its chemical and physical properties. • Strength prediction model for ASC agrees well with the test results. The aim of this work is to promote the utilization of aeolian sand for concrete production. The workability and mechanical property of aeolian sand concrete (ASC) is studied. The effect mechanisms of aeolian sand on the mechanical property of concrete are revealed from multiple scales. For the macro scale, use the pressure tester to test the compressive strength. For the mesoscopic, use the scanning electron microscope (SEM) to observe the structure of the interface transition zone (ITZ) and the nuclear magnetic resonance (NMR) to test the pore structure. Meanwhile, the distribution of chemical bonds is analyzed by the Fourier transform infrared (FT-IR) spectrometer and the microstructure of hydration products are characterized by the SEM for the microscopic. The results show that using parts of aeolian sand can improve the working and mechanical property of concrete. The physical influence mechanism is that it perfects the gradation of the aggregate and increases the density of concrete, reduces the effect of aggregate size and micro-region bleeding, improves the structure of ITZ and pores. For the chemical, it may accelerate the hydration reaction speed of cement and change the microstructure of hydration products. Finally, a strength prediction model of ASC is established based on the published and tested data, which agrees well with the tested result. [ABSTRACT FROM AUTHOR]

[Display omitted] • Forest managements reshaped the phyllosphere bacterial community. • The α -diversity increased, and β -diversity decreased. • The community stability and resistance increased, while the complexity decreased. • The keystone species altered following forest management. • Select-driven community assembly mechanisms increased in the managed forest. Research has shown that forest management can improve the post-drought growth and resilience of Qinghai spruce in the eastern Qilian Mountains, located on the northeastern Tibetan Plateau. However, the impact of such management on the tree-associated phyllosphere microbiome is not yet fully understood. This study provides new evidence of positive forest management effects on the phyllosphere microbiome after extreme drought, from the perspectives of community diversity, structure, network inference, keystone species, and assembly processes. In managed Qinghai spruce forest, the α -diversity of the phyllosphere bacterial communities increased, whereas the β -diversity decreased. In addition, the phyllosphere bacterial community became more stable and resistant, yet less complex, following forest management. Keystone species inferred from a bacterial network also changed under forest management. Furthermore, forest management mediated changes in community assembly processes, intensifying the influence of determinacy, while diminishing that of stochasticity. These findings support the hypothesis that management can re-assemble the phyllosphere bacterial community, enhance community stability, and ultimately improve tree growth. Overall, the study highlights the importance of forest management on the phyllosphere microbiome and furnishes new insights into forest conservation from the perspective of managing microbial processes and effects. [ABSTRACT FROM AUTHOR]

Tiantishan Grottoes, a famous site well known for its historical status in the spread of Buddhism art in ancient China, were selected for a comparison and analysis of microbial taxonomic characteristics on the wall paintings under different preservation conditions: in situ and ex situ conservation. A total of 12 samples were collected from three different cave wall paintings preserved in situ or ex situ . The 16/18S rRNA gene-based sequences revealed a high bacterial diversity and a relative low fungal abundance, including bacterial groups Firmicutes, Actinobacteria, Proteobacteria, Bacteroidetes, Cyanobacteria, Acidobacteria, Deinococcus-Thermus and Fusobacteria; and fungal groups Ascomycota and Basidiomycota. Among them, two bacterial genera of the Promicromonospora and Planomicrobium and fungal order of the Sordariales and the family of Trichocomaceae were dominant in the samples preserved ex situ . Some of them have been reported at other cultural heritage sites and associated with the biodeterioration of cultural relics. The over-growth of these microbes led to the abundant filaments formed visible on the surface of the ex situ wall paintings, which preserved under museum conditions. Application of preservation materials including animal glue and wet gypsum to take them off from grottoes and strengthen, and subsequent long-term preservation under poor conditions in museums were mainly responsible for the microbial outbreaks. To avoid similar problems in the future, reasonable intervention measures and strict micro-environmental control must be implemented to the ex situ preservation of wall paintings. Our results have profound significance for clarify the occurrence of microbial invasions and mechanisms on the wall paintings; it is helpful to development a reasonable artificial intervention measures for conservation work of the wall paintings in the future. [ABSTRACT FROM AUTHOR]

Microorganisms that are halophilic and halotolerant have gradually developed unique structures, physiologies, and genomes to survive. They are essential for ecological restoration and pollution control. This review emphasizes the critical role of halophilic and halotolerant microorganisms in plant stress tolerance, the ability to degrade a wide range of organic pollutants, the potential for cultural heritage conservation and restoration, and the impact on the spread of resistance genes. Halophilic and halotolerant microorganisms tolerate salt by controlling osmotic pressure in the cytoplasm via one of two major mechanisms: compatible solute accumulation or inorganic ion accumulation. Besides, the ability of halophilic and halotolerant microorganisms to survive high salt concentrations is also related to enzymatic proteins with fascinating physicochemical and structural properties. The advantage of halophilic enzymes is their ability to maintain enzyme stability and activity under high salt concentrations and organic reagents. The review of halophilic and halotolerant microorganisms is critically valuable for the reclamation of saline lands and pollutant degradation in highly saline environments. [Display omitted] • Eco-environmental restoration and sustainability in various types of saline environments are more challenging. • Halophilic and halotolerant microorganisms have unique advantages in ecological restoration and pollution control. • Halophilic and halotolerant microorganisms survive through conventional mechanisms and halophilic enzymes. • Halophilic enzymes can be more flexible in high salt environments. [ABSTRACT FROM AUTHOR]

The relative concentrations of carbon (C), nitrogen (N), and phosphorus (P) in plants, termed stoichiometry, influence the functioning and structuring of ecosystems by influencing important ecological processes. However, the stoichiometry of phylogenetically related plant species remains poorly understood. To understand the biogeographical drivers of this trait in Tamarix Lour., we collected 90 leaf samples from 30 sites containing four Tamarix species. C, N, and P concentrations and their stoichiometric ratios were determined. The mean leaf C, N, and P concentrations were 396.976 g/kg, 24.034 g/kg, and 1.689 g/kg, respectively. The C/N, C/P, and N/P ratios were 17.088, 256.650, and 15.051, respectively. C and N concentrations increased with increasing summer mean precipitation, whereas the C/N ratio declined. Soil pH negatively affected leaf C. Leaf P increased with increasing summer mean precipitation and decreased with increasing latitude, with the opposite trend being detected for C/P. N/P had a quadratic correlation with summer mean precipitation, increasing with increasing latitude. No phylogenetic signals were observed in stoichiometry. However, the quadratic equations for P, C/P, and N/P with the intraspecies nucleotide genetic diversity of T. chinensis Lour. were obtained, indicating that genetic components help drive elemental composition. Overall, our results showed that widespread Tamarix species exhibit stoichiometric adaptation strategies to heterogeneous environments. [ABSTRACT FROM AUTHOR]

Tamarix is a genus in family Tamaricaceae. The present study inferred phylogenetic trees for sixteen Tamarix species from China, whose status has remained unclear, using the nuclear internal transcribed spacer (ITS) region and four chloroplast DNA regions. Thirty ITS sequences from the GenBank database were added for expanded ITS analysis. The molecular phylogenies divide the Tamarix species into eight clades. Tamarix androssowii , T. gracilis , and T. laxa group together as a subclade closely related to T. gansuensis and T. elongata (clade A). Tamarix austromongolica , T. chinensis , T. hohenackeri , T. ramosissima , and T. sachensis cluster into clade B; T. karelinii from Gansu province is also in this clade. Tamarix leptostachya belongs to clade C, and one population of T. ramosissima from Gansu province is placed in this clade in the expanded ITS tree. Tamarix hispida groups with T. karelinii from Xinjiang province in clade D. Three putative T. hispida individuals from Gansu province and T. hispida from the US cluster into clade E. Finally, Tamarix arceuthoides , T. taklamakanensis , and T. aphylla form separate clades (F, G, and H, respectively). These molecular analyses are consistent with the current classification of certain Tamarix species based on morphological traits. [ABSTRACT FROM AUTHOR]

Pulmonary tuberculosis (PTB) is a major public health problem in China. Minqin, a Northwest county of China, has a very high number of annual PTB clinic visits and it is also known for its severe dust storms. The epidemic usually begins in February and ends in July, while the dust storms mainly occur throughout spring and early summer, thereby suggesting that there might be a close link between the causative agent of PTB and dust storms. We investigated the general impact of dust storms on PTB over time by analyzing the variation in weekly clinic visits in Minqin during 2005–2012. We used the Mann–Whitney–Pettitt test and a regression model to determine the seasonal periodicity of PTB and dust storms in a time series, as well as assessing the relationships between meteorological variables and weekly PTB clinic visits. After comparing the number of weekly PTB cases in Gansu province with dust storm events, we detected a clear link between the population dynamics of PTB and climate events, i.e., the onset of epidemics and dust storms (defined by an atmospheric index) occurred in almost the same mean week. Thus, particulate matter might be the cause of PTB outbreaks on dust storm days. It is highly likely that the significant decline in annual clinic visits was closely associated with improvements in the local environment, which prevented desertification and decreased the frequency of dust storm events. To the best of our knowledge, this is the first population-based study to provide clear evidence that a PTB epidemic was affected by dust storms in China, which may give insights into the association between this environmental problem and the evolution of epidemic disease. [ABSTRACT FROM AUTHOR]

[Display omitted] • The bacterial variation within microhabitats associated with the black stone of the Black Gobi desert were investigated. • Bacterial communities within microhabitats were highly different in the desert ecosystems. • Microhabitats formed by black stones support highly diverse and biologically active bacterial communities. • Major environmental controls were water content, total carbon, and total nitrogen. Desert soil around the black stones is highly complex, which substantially affects the diversity and composition of inhabiting microbes. The existence of black stones in the southern part of the Black Gobi desert of China could provide microhabitats for diverse bacterial communities that remain unexplored. Hence, Illumina MiSeq sequencing was used to determine the differences in bacterial communities associated within microhabitats in three sites of the Black Gobi desert, China. Our results show that bacterial communities are significantly affected by each microhabitat. For instance, the α -diversity of bacterial communities indicated more remarkable diversity and richness in these microhabitats. Considering β -diversity, variances were reported mainly in the Proteobacteria (30%), Actinobacteria (26%), Chloroflexi (19%), and Firmicutes (9%). Firmicutes were markedly enriched in the upper surface, especially in site 1. Compared to other microhabitats, the relative abundance of Proteobacteria was greater in the subsurface, and they were also more dominant in the other two sites. Network analysis of soil factors and bacterial genera showed that the most significant-occurrences were positively correlated, demonstrating potential synergistic interactions. Collective with the predicted function profiles and the redundancy analysis, these results indicated the highest variances in bacterial community structure and function in Black Gobi Desert ecosystems. These differences are likely closely related to the soil parameters, mainly water content, total carbon, and total nitrogen, and might be associated with black stones. This study concludes that microhabitats formed by black stones support highly diverse and biologically active bacterial communities. These microhabitats with extreme environmental conditions deliver new opportunities to explore soil bacterial communities at relevant spatial scales in the Black Gobi desert. [ABSTRACT FROM AUTHOR]

• The F-T fatigue life of concrete increases with increasing aeolian sand content. • Multi-scale influence of aeolian sand on concrete's frost resistance is revealed. • F-T damage of ASC is mainly caused by physical effect and weakly by chemical effect. • Aeolian sand changes concrete pore structure thereby affects its frost resistance. A comprehensive understanding of the freeze–thaw (F-T) degradation of aeolian sand concrete (ASC) and associated damage mechanism is important for its popularization and application. In this study, river sand was partially replaced by aeolian sand from the Mu Us Desert in Northwest China to produce ASC. Scanning electron microscopy, X-ray single crystal diffraction, nuclear magnetic resonance, and damage mechanics theory were applied to determine the damage mechanism caused by F-T cycling, and the multi-scale influence of aeolian sand on the frost resistance of concrete was constrained based on rapid F-T cycle tests. The results show that the F-T fatigue life of concrete increases with increasing aeolian sand content. The optimal frost resistance is achieved with 100% aeolian sand replacement despite its low strength, which is 19.49% higher than that of ordinary concrete. A quadratic parabolic relationship exists between the loss rates of mass, dynamic elastic modulus, compressive strength, and number of F-T cycles. The F-T damage of ASC is mainly dominated by physical effects and weakly by chemical effects. Concrete subjected to F-T cycling undergoes damage that progresses from the outside surface inward. The main drivers of the macroscopic property degradation of concrete are (1) scaling and debonding of the aggregate slurry in the interfacial transition zone and (2) cracking and expansion of the mortar matrix. The influence mechanism of aeolian sand on the frost resistance of concrete involves a change of porosity and concrete pore structure, which alters the moisture transmission path and thus affects the pore saturation and saturation rate. [ABSTRACT FROM AUTHOR]

Microorganisms can accelerate the deterioration of stone monuments. In this study, we used next-generation sequencing (Illumina MiSeq PE300 Platform) to investigate the microbial biofilm communities that have developed on sandstone in two famous Buddhist cave temples, the Maijishan Grottoes and Tiantishan Grottoes, located on the historical Silk Road in western China. We found high bacterial diversity and relatively low eukaryota diversity based on 16S and 18S ribosomal RNA (rRNA) sequencing analysis. The dominant bacterial groups were Cyanobacteria, Actinobacteria, Proteobacteria, Bacteroidetes, and Chloroflexi. The dominant eukaryota were Ascomycota, Basidiomycota, and Chytridiomycota. The most dominant genes among the bacteria were from Cyanobacteria (unclassified and no rank), Pseudonocardia , Kribbella, and Rubrobacter ; the dominant fungal genes were from unclassified Lecanorales and Capnodiales (unclassified and norank). These microbes form biofilms that will contribute to biodeterioration of the underlying sandstone. Combining with field monitoring and microscopic analysis, we determined that high bioreceptivity of the sandstone and locally available water were two important exogenous and endogenous factors that promoted microbial colonization, proliferation, and subsequent biofilm formation. The aforementioned microbes usually coexisted on the sandstone surfaces by building an inter-connected and dynamic community capable of adapting to and resisting the harsh local environmental conditions to survive and undergo succession. • A comparative analysis of microbial communities of stone biofilms of the two Grottoes. • High bioreceptivity of sandstone and available water are two of the most important factors for biofilm formation. • Strongly positive intra-domain connections contributed to resistance to harsh environment. [ABSTRACT FROM AUTHOR]

• The first study of microbial Hg methylation in a high altitude mountain glacier. • Hg methylation genes hgcA have the highest abundance in supraglacial cryoconite and dusty layers. • Microbial Hg methylation is consequently more likely in supraglacial cryoconite and dusty layers. • 37% of the hgcA sequences could not be classified into any known genus. The Qinghai-Tibet Plateau glaciers are an important carrier of mercury (Hg). With global warming, Hg enters into the downstream ecosystem in the melt waters, threatening human health and ecosystem security in the region. Methylmercury (MeHg), which has higher toxicity than Hg itself, is converted from inorganic Hg. However, little is known about the process of Hg methylation and, in particular, microbial Hg methylation in high altitude mountain glaciers. We combined Hg speciation measurements and metagenomic analysis of 6 sample types from the terminus of Laohugou No.12 glacier to elucidate potential microbially mediated Hg methylation. We found higher Hg concentrations in supraglacial cryoconite (SC) and dusty layer (DL) samples which contain considerable debris and dust. In addition, MeHg concentrations were highest in some of these SC and DL samples. Bacterial hgcA Hg methylation genes were present in all samples except supraglacial ice but were of highest abundance in SC and DL. This suggested that microbial Hg methylation is most likely to occur in SC and DL. There were 8 phyla of potential Hg methylation microorganisms, but 37% of the sequences could not be classified into any known genus. Most of the hgcA sequences were closely related to sequences from previously reported Hg methylating genera within the Deltaproteobacteria and Firmicutes, but the common Hg methylating Methanomicrobia were absent in glacial samples. [ABSTRACT FROM AUTHOR]

Recent decades have seen growing attention on viruses in the environment and their potential impacts as a result of global epidemics. Due to the diversity of viral species along with the complexity of environmental and host factors, virus extraction and detection methods have become key for the study of virus ecology. This review systematically summarises the methods for extracting and detecting pathogens from different environmental samples (e.g., soil, water, faeces, air) and biological samples (e.g., plants, animals) in existing studies, comparing their similarities and differences, applicability, as well as the advantages and disadvantages of each method. Additionally, this review discusses future directions for research in this field. The aim is to provide a theoretical foundation and technical reference for virus ecology research, facilitating further exploration and applications in this field.

Permafrost acts as a potential pathogen reservoir. With accelerating climate change and intensifying permafrost degradation, the release of these pathogens poses significant threats to ecosystems and public health. However, the changes in pathogenic communities during permafrost degradation remain unclear. This study utilized quantitative PCR and Illumina high-throughput sequencing to analyze the composition and quantities of potential pathogenic bacteria in four types of permafrost soil on the northeast edge of the Qinghai-Tibet Plateau (QTP): sub-stable permafrost (SSP), transition permafrost (TP), unstable permafrost (UP), and extremely unstable permafrost (EUP). The results showed that during permafrost degradation, the quantity of potential pathogenic bacteria decreased from 7.8 × 10 6 to 3.1 × 10 6  copies/g. Both the Richness and Shannon indices initially declined from SSP, to TP, UP, and then began to rise when permafrost degraded to EUP. A total of 216 potential pathogenic bacterial species were identified, including 166 animal pathogens, 28 zoonotic pathogens, and 22 plant pathogens. The pathogenic community intergroup differences (ANOSIM), unique taxa, and dominant pathogen analysis indicated the significant changes in pathogenic communities during permafrost degradation. The potential pathogenic community was significantly influenced by non-pathogenic bacterial communities (Procrustes analysis), with soil moisture being the primary environmental factor, followed by TDS, soil organic carbon, and total nitrogen. SourceTracker2 analysis indicated that the majority of potential pathogenic bacteria in the soil originated from external sources, only a small portion coming from the permafrost itself. These findings suggest that a large number of pathogens were released into the environment while also preserving amount from external sources. It elucidates that each stage of permafrost degradation presents unique biosecurity risks. This study highlights the release and redistribution of pathogenic bacteria associated with the potential public health risks. It provides the crucial insights into the ecological dynamics of permafrost degradation, emphasizing the need for ongoing monitoring and proactive management strategies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

A bacterial strain designated HT6-4 T was isolated from soil samples collected from the Flaming Mountain, Xinjiang, PR China. The purpose of this study was to describe a novel species and its characteristics, through genome sequencing and analysis of the relationship between the members of the genus Blastococcus , and explore the antiradiation, antioxidation and antibacterial capabilities of strain HT6-4 T . The polyphasic study confirmed the affiliation of strain HT6-4 T with the genus Blastococcus . Strain HT6-4 T was aerobic, Gram-stain-positive, non-budding, non-motile, catalase-positive and oxidase-negative. It grew at 10-37 °C, pH 5.0-8.0 and 0-4% (w/v) NaCl. Colonies were circular, smooth and bright orange in colour. In addition, strain HT6-4 T was drought tolerant. The predominant menaquinone was MK-9, with MK-8 as the minor component. The polar lipids of strain HT6-4 T were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, phosphatidylinositol, phospholipids, an unidentified aminolipid and two unidentified phospholipids. Whole-cell hydrolysates contain meso -diaminopimelic acid as the diagnostic diamino acid and ribose and galactose as diagnostic sugars. Its major fatty acids were iso-C 16 :  0 , C 17 :  1 ω 8 c and C 18 :  1 ω 9 c . The genome of strain HT6-4 T was 4.30 Mb in the whole-genome shotgun project. The G+C content was 73.9 mol%. The phylogenetic analysis based on the 16S rRNA gene sequence showed that strain HT6-4 T was closely related to Blastococcus jejuensis KST3-10 T (97.9%), Blastococcus capsensis BMG 804 T (97.8%), Bl astococcus aggregatus DSM 4725 T (97.5%), Blastococcus saxobsidens BC 444 T (97.5%), Blastococcus xanthinilyticus BMG 862 T (97.5%) and Blastococcus litoris GP-S2-8 T (97.5%). The average nucleotide identity (OrthoANI) and digital DNA-DNA hybridization (dDDH) values among strain HT6-4 T and B. jejuensis KST3-10 T , B. capsensis BMG 804 T , B. aggregatus DSM 4725 T , B. saxobsidens BC 444 T , B. xanthinilyticus BMG 862 T and B. litoris GP-S2-8 T were below the species delimitation thresholds. The genome of strain HT6-4 T contained antiradiation genes, antioxidant genes and antibacterial genes. Based on its morphological, physiological and chemical taxonomic characteristics, strain HT6-4 T (=KCTC 59234 T =GDMCC 1.4386 T ) should be classified as a novel species of the genus Bl astococcus with the proposed name Blastococcus montanus sp. nov.

Bacteria-derived hydrogen sulfide (H 2 S) often contributes to the emergence of antibiotic-recalcitrant bacteria, especially persister (a sub-population of dormant bacteria), thus causing the treatment failure of Catheter-associated urinary tract infection (CAUTI). Here, an H 2 S harvester nanosystem to prevent the generation of persister bacteria and disrupt the dense biofilm matrix by the self-adaptive ability of shape-morphing is prepared. The nanosystem possesses a core-shell structure that is composed of liquid metal nanoparticle (LM NP), AgNPs, and immobilized urease. The nanosystem decomposes urea contained in urine to generate ammonia for eliminating bacteria-derived H 2 S. Depending on the oxidative layer of liquid metal, the nanosystem also constitutes a long-lasting reservoir for temporarily storing bacteria-derived H 2 S, when urease transiently overloads or in the absence of urine in a catheter. Depriving H 2 S can prevent the emergence of persistent bacteria, enhancing the bacteria-killing efficiency of Ga 3+ and Ag + ions. Even when the biofilm has formed, the urine flow provides heat to trigger shape morphing of the LM NP, tearing the biofilm matrix. Collectively, this strategy can turn trash (urea) into treasure (H 2 S scavengers and biofilm rippers), and provides a new direction for the antibacterial materials application in the medical field., (© 2024 Wiley‐VCH GmbH.)

Radiation protection is an important field of study, as it relates to human health and environmental safety. Radiation-resistance mechanisms in extremophiles are a research hotspot, as this knowledge has great application value in bioremediation and development of anti-radiation drugs. Mount Everest, an extreme environment of high radiation exposure, harbors many bacterial strains resistant to radiation. However, owing to the difficulties in studying them because of the extreme terrain, many remain unexplored. In this study, a novel species (herein, S7-12 T ) was isolated from the moraine of Mount Everest, and its morphology and functional and genomic characteristics were analyzed. The strain S7-12 T is white in color, smooth and rounded, non-spore-forming, and non-motile and can survive at a UV intensity of 1000 J/m 2 , showing that it is twice as resistant to radiation as Deinococcus radiodurans . Radiation-resistance genes, including IbpA and those from the rec and CspA gene families, were identified. The polyphasic taxonomic approach revealed that the strain S7-12 T (=KCTC 59114T =GDMCC 1.3458T) is a new species of the genus Knoellia and is thus proposed to be named glaciei . The in-depth study of the genome of strain S7-12 T will enable us to gain further insights into its potential use in radiation resistance. Understanding how microorganisms resist radiation damage could reveal potential biomarkers and therapeutic targets, leading to the discovery of potent anti-radiation compounds, thereby improving human resistance to the threat of radiation.

Introduction: T-sheep and H-sheep exhibit different environmental adaptability and production performance. The rumen microbiome has co-evolved with hosts and plays a vital role in nutrient digestion and energy metabolism. In our previous study, we found that T-sheep have a higher efficiency in energy metabolism than H-sheep, but the rumen microbial community remains unclear., Methods: In this study, we determined the rumen bacterial profile and rumen fermentation parameters to reveal the bacterial profiles and predictive functions among breeds and diets with four different energy levels, as well as the correlation between bacterial profiles and rumen fermentation characteristics., Results: The results showed that the rumen total volatile fatty acids (VFAs), acetate, butyrate, total branched-chain VFAs, iso-butyrate, and iso-valerate were higher in T-sheep than H-sheep. The alpha diversity of ruminal bacteria is not affected by dietary energy, but it shows a distinction between the sheep breeds. Specifically, T-sheep rumen bacteria exhibit higher alpha diversity than H-sheep. The beta diversity of ruminal bacteria is not influenced by dietary energy or sheep breeds, indicating similar communities of ruminal bacteria between different diets and sheep breeds. The phyla of Bacteroidetes and Firmicutes predominate in the rumen, with a higher relative abundance of Firmicutes observed in T-sheep than H-sheep. The two most abundant genera in the rumen were Prevotella 1 and Rikenellaceae RC9 gut group. Prevotella 1 is the predominant bacterial genus in the rumen of H-sheep, while the Rikenellaceae RC9 gut group dominates in the rumen of T-sheep. Microbial co-occurrence network analysis reveals that variations in rumen fermentation characteristics result from differences in module abundance, with a higher abundance of VFA-producing modules observed in the rumen of T-sheep. Microbial function prediction analysis showed that dietary energy rarely alters the functional composition of rumen bacteria. However, there were differences in the functions of rumen bacteria between sheep breeds, with T-sheep showing a greater emphasis on energy metabolism-related functions, while H-sheep showed a greater emphasis on protein metabolism-related functions., Discussion: These findings provide evidence of the special rumen microbial community that helps T-sheep efficiently obtain energy from low-protein and low-energy diets, enabling them to survive in the extreme environment of the Qinghai-Tibet Plateau., Competing Interests: HC was employed by Shandong Huakun Rural Revitalization Institute Co., Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Wu, Zhang, Zhang, Zhou, Cong, Yang and Liu.)

A rich diversity of radiation-resistant (Rr) and desiccation-resistant (Dr) bacteria has been found in arid habitats of the world. Evidence from scientific research has linked their origin to reactive oxygen species (ROS) intermediates. Rr and Dr. bacteria of arid regions have the potential to regulate imbalance radicals and evade a higher dose of radiation and oxidation than bacterial species of non-arid regions. Photochemical-activated ROS in Rr bacteria is run through photo-induction of electron transfer. A hypothetical model of the biogeochemical cycle based on solar radiation and desiccation. These selective stresses generate oxidative radicals for a short span with strong reactivity and toxic effects. Desert-inhibiting Rr bacteria efficiently evade ROS toxicity with an evolved antioxidant system and other defensive pathways. The imbalanced radicals in physiological disorders, cancer, and lung diseases could be neutralized by a self-sustaining evolved Rr bacteria antioxidant system. The direct link of evolved antioxidant system with intermediate ROS and indirect influence of radiation and desiccation provide useful insight into richness, ecological diversity, and origin of Rr bacteria capabilities. The distinguishing features of Rr bacteria in deserts present a fertile research area with promising applications in the pharmaceutical industry, genetic engineering, biological therapy, biological transformation, bioremediation, industrial biotechnology, and astrobiology., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be constructed as a potential conflict of interest., (Copyright © 2024 Khan, Liu, Zhang and Li.)

We isolated and analyzed a novel, Gram-stain-positive, aerobic, rod-shaped, non-motile actinobacterium, designated as strain ZFBP1038 T , from rock sampled on the north slope of Mount Everest. The growth requirements of this strain were 10-37 °C, pH 4-10, and 0-6% (w/v) NaCl. The sole respiratory quinone was MK-9, and the major fatty acids were anteiso-C 15:0 and iso-C 17:0 . Peptidoglycan containing meso-diaminopimelic acid, ribose, and glucose were the major cell wall sugars, while polar lipids included diphosphatidyl glycerol, phosphatidyl glycerol, an unidentified phospholipid, and an unidentified glycolipid. A phylogenetic analysis based on 16S rRNA gene sequences showed that strain ZFBP1038 T has the highest similarity with Spelaeicoccus albus DSM 26341  T (96.02%). ZFBP1038 T formed a distinct monophyletic clade within the family Brevibacteriaceae and was distantly related to the genus Spelaeicoccus. The G + C content of strain ZFBP1038 T was 63.65 mol% and the genome size was 4.05 Mb. Digital DNA-DNA hybridization, average nucleotide identity, and average amino acid identity values between the genomes of strain ZFBP1038 T and representative reference strains were 19.3-25.2, 68.0-71.0, and 52.8-60.1%, respectively. Phylogenetic, phenotypic, and chemotaxonomic characteristics as well as comparative genome analyses suggested that strain ZFBP1038 T represents a novel species of a new genus, for which the name Saxibacter gen. nov., sp. nov. was assigned with the type strain Saxibacter everestensis ZFBP1038 T (= EE 014  T  = GDMCC 1.3024  T  = JCM 35335  T )., (© 2024. The Author(s), under exclusive licence to Microbiological Society of Korea.)

Gram-stain-negative, aerobic, rod-shaped, non-motile bacterium strain ZFBP2030 T was isolated from a rock on the North slope of Mount Everest. This strain contained a unique ubiquinone-10 (Q-10) as a predominant respiratory quinone. Among the tested fatty acids, the strain contained summed feature 8, C 14:0 2OH, and C 16:0 , as major cellular fatty acids. The polar lipid profile contained phosphatidyl glycerol, phosphatidyl ethanolamine, three unidentified phospholipids, two unidentified aminolipids, and six unidentified lipids. The cell-wall peptidoglycan was a meso-diaminopimelic acid, and cell-wall sugars were ribose and galactose. Phylogenetic analyses based on 16S rRNA gene sequence revealed that strain ZFBP2030 T was a member of the genus Sphingomonas, exhibiting high sequence similarity to the 16S rRNA gene sequences of Sphingomonas aliaeris DH-S5 T (97.9%), Sphingomonas alpina DSM 22537 T (97.3%) and Sphingomonas hylomeconis CCTCC AB 2013304 T (97.0%). The 16S rRNA gene sequence similarity between ZFBP2030 T and other typical strains was less than 97.0%. The average amino acid identity values, average nucleotide identity, and digital DNA-DNA hybridization values between strain ZFBP2030 T and its highest sequence similarity strains were 56.9-79.9%, 65.1-82.2%, and 19.3-25.8%, respectively. The whole-genome size of the novel strain ZFBP2030 T was 4.1 Mbp, annotated with 3838 protein-coding genes and 54 RNA genes. Moreover, DNA G + C content was 64.7 mol%. Stress-related functions predicted in the subsystem classification of the strain ZFBP2030 T genome included osmotic, oxidative, cold/heat shock, detoxification, and periplasmic stress responses. The overall results of this study clearly showed that strain ZFBP2030 T is a novel species of the genus Sphingomonas, for which the name Sphingomonas endolithica sp. nov. is proposed. The type of strain is ZFBP2030 T (= EE 013 T  = GDMCC 1.3123 T  = JCM 35386 T )., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

A novel Streptomyces strain, designated 3_2 T , was isolated from soil under the black Gobi rock sample of Northwest China. The taxonomic position of this strain was revealed by a polyphasic approach. Comparative analysis of the 16S rRNA gene sequences indicated that 3_2 T was closely related to the members of the genus Streptomyces, with the highest similarity to Streptomyces rimosus subsp. rimosus CGMCC 4.1438 (99.17%), Streptomyces sioyaensis DSM 40032 (98.97%). Strain 3_2 T can grow in media up to 13% NaCl. The genomic DNA G + C content of strain 3_2 T was 69.9%. We obtained the genomes of 22 Streptomyces strains similar to strain 3_2 T , compared the average nucleotide similarity, dDDH and average amino acid identity, and found that the genomic similarity of the new isolate 3_2 T to all strains was below the threshold for interspecies classification. Chemotaxonomic data revealed that strain 3_2 T possessed MK-9 (H 6 ) and MK-9 (H 8 ) as the major menaquinones. The cell wall contained LL-diaminopimelic acid (LL-DAP) and the whole-cell sugars were ribose and glucose. The major fatty acid methyl esters were iso-C 16:0 (23.6%) and anteiso-C 15:0 (10.4%). The fermentation products of strain 3_2 T were inhibitory to Staphylococcus aureus and Bacillus thuringiensi. The genome of 3_2 T was further predicted using anti-smash and the strain was found to encode the production of 41 secondary metabolites, and these gene clusters may be key to the good inhibitory activity exhibited by the strain. Genomic analysis revealed that strain 3_2 T can encode genes that produce a variety of genes in response to environmental stresses, including cold shock, detoxification, heat shock, osmotic stress, oxidative stress, and these genes may play a key role in the harsh environment in which the strain can survive. Therefore, this strain represents a novel Streptomyces species, for which the name Streptomyces halobius sp. nov. is proposed. The type strain is 3_2 T (= JCM 34935 T  = GDMCC 4.217 T )., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Glaciers retreating due to global warming create important new habitats, particularly suitable for studying ecosystem development where nitrogen is a limiting factor. Nitrogen availability mainly results from microbial decomposition and transformation processes, including nitrification. AOA and AOB perform the first and rate-limiting step of nitrification. Investigating the abundance and diversity of AOA and AOB is essential for understanding early ecosystem development. The dynamics of AOA and AOB community structure along a soil chronosequence in Tianshan No. 1 Glacier foreland were analyzed using qPCR and clone library methods. The results consistently showed low quantities of both AOA and AOB throughout the chronosequence. Initially, the copy numbers of AOB were higher than those of AOA, but they decreased in later stages. The AOB community was dominated by "Nitrosospira cluster ME", while the AOA community was dominated by "the soil and sediment 1". Both communities were potentially connected to supra- and subglacial microbial communities during early stages. Correlation analysis revealed a significant positive correlation between the ratios of AOA and AOB with soil ammonium and total nitrogen levels. These results suggest that variations in abundance and diversity of AOA and AOB along the chronosequences were influenced by ammonium availability during glacier retreat.

Nocardioides , a genus belonging to Actinomycetes , can endure various low-nutrient conditions. It can degrade pollutants using multiple organic materials such as carbon and nitrogen sources. The characteristics and applications of Nocardioides are described in detail in this review, with emphasis on the degradation of several hard-to-degrade pollutants by using Nocardioides , including aromatic compounds, hydrocarbons, haloalkanes, nitrogen heterocycles, and polymeric polyesters. Nocardioides has unique advantages when it comes to hard-to-degrade pollutants. Compared to other strains, Nocardioides has a significantly higher degradation rate and requires less time to break down substances. This review can be a theoretical basis for developing Nocardioides as a microbial agent with significant commercial and application potential.

Background: New antibiotics are urgently needed in clinical treatment of superdrug-resistant bacteria. Nonribosomal peptides (NRPs) are a major source of antibiotics because they exhibit structural diversity, and unique antibacterial mechanisms and resistance. Analysis of gene clusters of S. agglomeratus 5-1-3 showed that Clusters 3, 6, 12, 21, and 28 were used to synthesize NRPs. Here, we examined secondary metabolites of S. agglomeratus 5-1-3 isolated from soils in the Qinghai-Tibet Plateau, China, for NRPs with antibacterial activity., Results: We isolated a total of 36 Streptomyces strains with distinct colony morphological characteristics from 7 soil samples. We screened 8 Streptomyces strains resistant to methicillin-resistant Staphylococcus aureus (MRSA). We then selected S. agglomeratus 5-1-3 for further study based on results of an antibacterial activity test. Here, we isolated three compounds from S. agglomeratus 5-1-3 and characterized their properties. The crude extract was extracted with ethyl acetate and purified with column chromatography and semipreparative high-performance liquid chromatography (HPLC). We characterized the three compounds using NMR analyses as echinomycin (1), 5,7,4'-trihydroxy-3.3',5'-trimethoxy flavone (2), and 2,6,2', 6'-tetramethoxy-4,4-bis(2,3-epoxy-1-hydroxypropyl)-biphenyl (3). We tested the antibacterial activity of pure compounds from strain 5-1-3 with the Oxford cup method. NRP echinomycin (1) showed excellent anti-MRSA activity with a minimum inhibitory concentration (MIC) of 2.0 μg/mL. Meanwhile, MIC of compound 2 and 3 was 128.0 μg/mL for both. In addition, 203 mg of echinomycin was isolated from 10 L of the crude extract broth of strain 5-1-3., Conclusion: In this study, S. agglomeratus 5-1-3 with strong resistance to MRSA was isolated from the soils in the Qinghai-Tibet Plateau. Strain 5-1-3 had a high yield of echinomycin (1) an NRP with a MIC of 2 μg/mL against MRSA. We propose that echinomycin derived from S. agglomeratus 5-1-3 may be a potent antibacterial agent for pharmaceutical use., (© 2023. The Author(s).)

Background: The bacterial mechanisms responsible for hydrogen peroxide (H 2 O 2 ) scavenging have been well-reported, yet little is known about how bacteria isolated from cold-environments respond to H 2 O 2 stress. Therefore, we investigated the transcriptional profiling of the Planomicrobium strain AX6 strain isolated from the cold-desert ecosystem in the Qaidam Basin, Qinghai-Tibet Plateau, China, in response to H 2 O 2 stress aiming to uncover the molecular mechanisms associated with H 2 O 2 scavenging potential., Methods: We investigated the H 2 O 2 -scavenging potential of the bacterial Planomicrobium strain AX6 isolated from the cold-desert ecosystem in the Qaidam Basin, Qinghai-Tibet Plateau, China. Furthermore, we used high-throughput RNA-sequencing to unravel the molecular aspects associated with the H 2 O 2 scavenging potential of the Planomicrobium strain AX6 isolate., Results: In total, 3,427 differentially expressed genes (DEGs) were identified in Planomicrobium strain AX6 isolate in response to 4 h of H 2 O 2 (1.5 mM) exposure. Besides, Kyoto Encyclopedia of Genes and Genomes pathway and Gene Ontology analyses revealed the down- and/or up-regulated pathways following H 2 O 2 treatment. Our study not only identified the H 2 O 2 scavenging capability of the strain nevertheless also a range of mechanisms to cope with the toxic effect of H 2 O 2 through genes involved in oxidative stress response. Compared to control, several genes coding for antioxidant proteins, including glutathione peroxidase (GSH-Px), Coproporphyrinogen III oxidase, and superoxide dismutase (SOD), were relatively up-regulated in Planomicrobium strain AX6, when exposed to H 2 O 2 ., Conclusions: Overall, the results suggest that the up-regulated genes responsible for antioxidant defense pathways serve as essential regulatory mechanisms for removing H 2 O 2 in Planomicrobium strain AX6. The DEGs identified here could provide a competitive advantage for the existence of Planomicrobium strain AX6 in H 2 O 2 -polluted environments., (© 2022. The Author(s).)

A 4 H -type BaMnO 3 single crystal was prepared by combining the floating zone method with high-pressure treatment at 5 GPa and 1023 K. The crystal crystallizes to a hexagonal structure with space group P 6 3 / mmc and lattice parameters a = 5.63723(5) Å and c = 9.22355(8) Å. In this structure, face-sharing MnO 6 octahedral dimers connect with each other by corner O atoms along the c -axis direction, forming an -A-B-A-C-type 4 H arrangement. A long-range antiferromagnetic (AFM) phase transition is found to occur at T N ≈ 263 K. When the synthesis pressure increases to 20 GPa, a new polymorphic phase is obtained. This higher-pressure phase still possesses the hexagonal P 6 3 / mmc symmetry, but the lattice parameters change to be a = 5.61349(2) Å and c = 13.66690(9) Å with a unit cell volume reduction of 2.05%. In this new phase, the c -axis MnO 6 dimers are separated by MnO 6 octahedral layers in the ab plane, forming an -A-B-C-A-C-B-type 6 H structure. The 6 H phase exhibits two long-range AFM orderings at T N1 ≈ 220 K and T N2 ≈ 25 K, respectively. The different magnetic properties are discussed on the basis of the detailed structural constitutions of 4 H - and 6 H -BaMnO 3 .

A new oxide, LaMn 3 Co 2 Mn 2 O 12 , was synthesized under high-pressure (7 GPa) and high-temperature (1423 K) conditions. The compound crystallizes in an AA' 3 B 4 O 12 -type quadruple perovskite structure with space group Im 3̅. The Rietveld structural analysis combined with soft X-ray absorption spectroscopy reveals the charge combination to be LaMn 3+ 3 Co 2+ 2 Mn 4+ 2 O 12 , where the La 3+ and Mn 3+ are 1:3 ordered respectively at the A and A' sites, whereas the Co 2+ and Mn 4+ are disorderly distributed at the B site. This is in sharp contrast to R 2 Co 2+ Mn 4+ O 6 (R = La and rare earth) double perovskites, in which the Co 2+ and Mn 4+ charge states are always orderly distributed with a rocksalt-type fashion, giving rise to a long-range magnetic ordering. As a result, LaMn 3 Co 2 Mn 2 O 12 displays spin glassy magnetic properties due to the random Co 2+ and Mn 4+ distribution, as demonstrated by dc and ac magnetic susceptibility as well as specific heat measurements. Possible factors that affect the B-site degree of order in perovskite structures are discussed.

A Gram-staining-positive and aerobic coccus with the ability to degrade petroleum bacterium, designated Y42 T , was isolated from the Lenghu oil field located in the northern margin of the Qaidam Basin. Phylogenetic and signature nucleotides analyses revealed that strain Y42 T belongs to the genus Planococcus. The multiple sequence alignments of 16S rRNA and housekeeping genes showed that strain Y42 T formed a distinct lineage with the other Planococcus clade. The average nucleotide identity (ANI) and DNA-DNA hybridization values (DDH) between strain Y42 T and the reference strains were 69.5-70.1 and 19.4-21.7%, respectively, which values were below the threshold for species delineation. The major fatty acids of strain Y42 T were anteiso-C 15:0 . The respiratory quinone was MK-7 (71.8%) as the predominant menaquinone followed the MK-6 (28.2%) and the cell-wall hydrolysates contained LL-diaminopimelic acid. The polar lipid was composed of diphosphatidyl glycerol, phosphatidyl glycerol, phosphoglycolipid, aminophospholipid and four unidentified lipids. The peptidoglycan type was A4α (L-Lys-D-Glu). The strain Y42 T possessed larger genome (approximately 4 MB) and revealed obvious differences for the abundance of the COG categories compared with the other Planococcus bacteria. Also, the strain Y42 T also possessed more unique orthologous proteins. The structural characteristics of the strain Y42 T genome provided a competitive advantage for better survival in petroleum-polluted environments. Combined with the 16S rRNA gene and genome sequence, phenotypic as well as chemotaxonomic characterisations, strain Y42 T is considered to represent a novel species of the genus Planococcus, for which the name Planococcus lenghuensis sp. nov. be proposed. The type strain is Y42 T (= CGMCC 1.15921 T  = JCM 32719 T ).

Proxy-based reconstructions and modeling of Holocene spatiotemporal precipitation patterns for China and Mongolia have hitherto yielded contradictory results indicating that the basic mechanisms behind the East Asian Summer Monsoon and its interaction with the westerly jet stream remain poorly understood. We present quantitative reconstructions of Holocene precipitation derived from 101 fossil pollen records and analyse them with the help of a minimal empirical model. We show that the westerly jet-stream axis shifted gradually southward and became less tilted since the middle Holocene. This was tracked by the summer monsoon rain band resulting in an early-Holocene precipitation maximum over most of western China, a mid-Holocene maximum in north-central and northeastern China, and a late-Holocene maximum in southeastern China. Our results suggest that a correct simulation of the orientation and position of the westerly jet stream is crucial to the reliable prediction of precipitation patterns in China and Mongolia.

A strain of Nocardia isolated from crude oil-contaminated soils in the Qinghai-Tibetan Plateau degrades nearly all components of crude oil. This strain was identified as Nocardia soli Y48, and its growth conditions were determined. Complete genome sequencing showed that N. soli Y48 has a 7.3 Mb genome and many genes responsible for hydrocarbon degradation, biosurfactant synthesis, emulsification and other hydrocarbon degradation-related metabolisms. Analysis of the clusters of orthologous groups (COGs) and genomic islands (GIs) revealed that Y48 has undergone significant gene transfer events to adapt to changing environmental conditions (crude oil contamination). The structural features of the genome might provide a competitive edge for the survival of N. soli Y48 in oil-polluted environments and reflect the adaptation of coexisting bacteria to distinct nutritional niches., (Copyright © 2018. Published by Elsevier Inc.)

This study investigates the biodegradation of crude oil by a mixed culture of bacteria isolated from the Qinghai-Tibet plateau using gas chromatography-mass spectrometer (GC-MS) and the gravimetric method. The results showed that a mixed culture has a stronger ability to degrade hydrocarbon than pure cultures. Once both Nocardia soli Y48 and Rhodococcus erythropolis YF28-1 (8) were present in a culture, the culture demonstrated the highest crude oil removal efficiency of almost 100% after 10 days of incubation at 20 °C. Moreover, further analysis of the degradation mechanisms used by the above strains, which revealed utilization of different n-alkane substrates, indicated the diversity of evolution and variations in different strains, as well as the importance of multiple metabolic mechanisms for alkane degradation. Therefore, it is concluded that a mixed culture of Y48 and YF28-1 (8) strains can provide a more effective method for bioremediation of hydrocarbon-contaminated soil in permafrost regions.

A novel actinobacterial strain, designated S10 T , was isolated from a sand sample collected from the Qaidam Basin in Qinghai province, China. The strain S10 T exhibited antibacterial activity against MRSA. The taxonomic position of the strain S10 T was determined by a polyphasic approach. There were six copies of 16S rDNA in S10 T which were not same exactly (MH257693-MH257698). Phylogenetic analysis of 16S rRNA gene sequences indicated the strain belonging to the genus Streptomyces and it showed high sequence similarities with Streptomyces chartreusis NBRC 12753 T (99.31%), Streptomyces phaeoluteigriseus DSM 41896 T (99.24%), Streptomyces variegatus NRRL B-16380 T (99.17%) and Streptomyces flavovariabilis NRRL B-16367 T (99.17%) comparing with MH257693, MH257695, MH257696, MH257697, and MH257698. Similarities with Streptomyces kunmingensis NBRC14463 T (98.82%), Streptomyces bungoensis DSM 41781 T (98.76%), S. chartreusis NBRC 12753 T (98.69%) and S. phaeoluteigriseus DSM 41896 T (98.62%) with MH257694. Whole-genome average nucleotide identity (ANI) values between strain S10 T and S. chartreusis NBRC 12753 T , S. phaeoluteigriseus DSM 41896 T , S. variegatus NRRL B-16380T, S. flavovariabilis NRRL B-16367 T , S. kunmingensis NBRC 14463 T , S. bungoensis DSM 41781 T were 83.63%, 82.89%, 92.55%, 92.51%, 79.29, and 82.87%, respectively, suggesting that the strain S10 T represented a new species. A phylogenetic analysis comparing the S10 T genome with those of 336 other sequenced Streptomyces genomes confirmed its relatedness with Streptomyces variegatus NRRL B-16380 T and Streptomyces flavovariabilis NRRL B-16367 T . Strain S10 T contained LL-diaminopimelic acid in the cell wall. The predominant menaquinones were MK-9(H 6 ) and MK-9(H 8 ) and the major fatty acids were iso-C 15:0, anteiso-C 15:0 , iso-C 16:0 , and anteiso-C 17:0 . Phospholipids detected were diphosphatidyl glycerol, phosphatidyl ethanolamine, phosphatidyl choline, three unknown phospholipids, an unknown aminophospholipid and an unknown phosphatidyl glycolipid. On the basis of these genotypic and phenotypic data, it is proposed that isolate S10 T (=JCM 31184 T =CGMCC 4.7315 T ) should be classified in the genus Streptomyces as Streptomyces qaidamensis sp. nov.

As a glacier retreats, barren areas are exposed, and these barren areas are ideal sites to study microbial succession. In this study, we characterized the soil culturable bacterial communities and biochemical parameters of early successional soils from a receding glacier in the Tianshan Mountains. The total number of culturable bacteria ranged from 2.19×10 5 to 1.30×10 6 CFUg -1 dw and from 9.33×10 5 to 2.53×10 6 CFUg -1 dw at 4°C and 25°C, respectively. The number of culturable bacteria in the soil increased at 25°C but decreased at 4°C along the chronosequence. The total organic carbon, total nitrogen content, and enzymatic activity were relatively low in the glacier foreland. The number of culturable bacteria isolated at 25°C was significantly positively correlated with the TOC and TN as well as the soil urease, protease, polyphenoloxidase, sucrase, catalase, and dehydrogenase activities. We obtained 358 isolates from the glacier foreland soils that clustered into 35 groups using amplified ribosomal DNA restriction analysis. These groups are affiliated with 20 genera that belong to six taxa, namely, Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Actinobacteria, Bacteroides, and Deinococcus-Thermus, with a predominance of members of Actinobacteria and Proteobacteria in all of the samples. A redundancy analysis showed that the bacterial succession was divided into three periods, an early stage (10a), a middle stage (25-74a), and a late stage (100-130a), with the total number of culturable bacteria mainly being affected by the soil enzymatic activity, suggesting that the microbial succession correlated with the soil age along the foreland., (Copyright © 2018. Published by Elsevier Editora Ltda.)