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Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Gut microbiota influences nutrient metabolism and immunity of animal hosts. Better understanding of the composition and diversity of gut microbiota contributes to conservation and management of threatened animals both in situ and ex situ. In this study, we applied 16S rRNA gene amplicon sequencing to evaluate the composition and diversity of the fecal bacterial community of four gibbon genera (Family Hylobatidae) at four Chinese zoos. The results showed that the dominant bacterial phyla were Bacteroidetes, Firmicutes, and Proteobacteria and dominant families were Prevotellaceae (Bacteroidetes), Spirochaetaceae (Spirochaetes) and Ruminococcaceae (Firmicutes) in the gut of all gibbons. Both captive site and host genus had significant effects on the relative abundance of dominant bacteria and structure of gut bacterial community. We found that captive site and host genus did not solely impact gut bacterial diversity, but the interaction between them did. This study provides basic knowledge for gut microbiota of all four gibbon genera and contributes to management and conservation of captive gibbons. RESEARCH HIGHLIGHTS: The results showed that the dominant bacterial phyla were Bacteroidetes, Firmicutes, and Proteobacteria and dominant families were Prevotellaceae (Bacteroidetes), Spirochaetaceae (Spirochaetes) and Ruminococcaceae (Firmicutes) in the gut of all gibbons. Both captive site and host genus had significant effects on the relative abundance of dominant bacteria and structure of gut bacterial community. Captive site and host genus did not solely impact gut bacterial diversity, but the interaction between them did. [ABSTRACT FROM AUTHOR]

The environmental burden due to industrial activities has been quite observable in the last few years, with heavy metals (HMs) like lead, cadmium, and arsenic inducing serious perturbations to the microbial ecosystem of groundwater. Studies carried out in North China, a region known for interconnection of industrial and groundwater systems, sought to explore the natural mechanisms of adaptation of microbes to groundwater contamination. The results showed that heavy metals permeate from surface increased the diversity and abundance of microbial communities in groundwater, producing an average decrease of 40.84% and 34.62% in the relative abundance of Bacteroidetes and Proteobacteria in groundwater, respectively. Meanwhile, the key environmental factors driving the evolution of microbial communities shift from groundwater nutrients to heavy metals, which explained 50.80% of the change in the microbial community composition. Microbial indicators are more sensitive to HMs pollution and could accurately identify industrial area where HMs permeation occurred and other extraneous pollutants. The phylum Bacteroidetes could act as appropriate indicators for the identification. Significant genera that were identified, being Mesorhizobium, Clostridium, Bacillus and Mucilaginibacter, were found to play important roles in the microbial network in terms of the potential to assist in groundwater clean-up. Notably, pollution from heavy metals has diminished the effectiveness and resilience of microbial communities in groundwater, thereby heightening the susceptibility of these normally stable microbial ecosystems. These findings offer new perspectives on how to monitor and detect groundwater pollution, and provide scientific guidance for developing suitable remediation methods for groundwater contaminated with heavy metals. Future research is essential explore the application of metal-tolerant or resistant bacteria in bioremediation strategies to rehabilitate groundwater systems contaminated by HMs., 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 Ltd. All rights reserved.)

Phosphate-solubilizing bacteria (PSB) have beneficial effects on plant health and soil composition. To date, studies of PSB in soil have largely been performed under field or greenhouse conditions. However, less is known about the impact of introducing indigenous PSB in the field, including their effects on the local microbial community. In this study, we conducted greenhouse and field experiments to explore the effects of the addition of indigenous PSB on the growth of Chenmou elm (Ulmus chenmoui) and on the diversity and composition of the bacterial community in the soil. We obtained four bacterial isolates with the highest phosphate-solubilizing activity: UC_1 (Pseudomonas sp.), UC_M (Klebsiella sp.), UC_J (Burkholderia sp.), and UC_3 (Chryseobacterium sp.). Sequencing on the Illumina MiSeq platform showed that the inoculated PSB did not become the dominant strains in the U. chenmoui rhizosphere. However, the soil bacterial community structure was altered by the addition of these PSB. The relative abundance of Chloroflexi decreased significantly in response to PSB application in all treatment groups, whereas the populations of several bacteria, including Proteobacteria and Bacteroidetes, increased. Network analysis indicated that Chloroflexi was the most strongly negatively correlated with Proteobacteria, whereas Proteobacteria was strongly positively correlated with Bacteroidetes. Our findings indicate that inoculation with PSB (UC_1, UC_M, UC_J, and UC_3) can improve the growth of U. chenmoui and regulate its rhizosphere microbial community. Therefore, inoculation with these bacterial strains could promote the efficient cultivation and production of high-quality plant materials. [ABSTRACT FROM AUTHOR]

The gut microbiota (GM) and its potential functions play a crucial role in maintaining host health and longevity. The aim of this study was to investigate the potential relationship between GM and longevity. We collected fecal samples from 92 healthy volunteers (middle-aged and elderly: 43-79 years old; longevity: ≥ 90 years old) from Changshou Town, Zhongxiang City, Hubei, China. In addition, we collected samples from 30 healthy middle-aged and elderly controls (aged 51-70 years) from Wuhan, Hubei. The 16S rDNA V3 + V4 region of the fecal samples was sequenced using high-throughput sequencing technology. Diversity analysis results showed that the elderly group with longevity and the elderly group with low body mass index (BMI) exhibited higher α diversity. However, no significant difference was observed in β diversity. The results of the microbiome composition indicate that Firmicutes, Proteobacteria, and Bacteroidota are the core phyla in all groups. Compared to younger elderly individuals, Akkermansia and Lactobacillus are significantly enriched in the long-lived elderly group, while Megamonas is significantly reduced. In addition, a high abundance of Akkermansia is a significant characteristic of elderly populations with low BMI values. Furthermore, the functional prediction results showed that the elderly longevity group had higher abilities in short-chain fatty acid metabolism, amino acid metabolism, and xenobiotic biodegradation. Taken together, our study provides characteristic information on GM in the long-lived elderly population in Changshou Town. This study can serve as a valuable addition to the current research on age-related GM. KEY POINTS: • The gut microbiota of elderly individuals with longevity and low BMI exhibit higher alpha diversity • Gut microbiota diversity did not differ significantly between genders in the elderly population • Several potentially beneficial bacteria (e.g., Akkermansia and Lactobacillus) are enriched in long-lived individuals., (© 2024. The Author(s).)

Three Gram-stain-negative, aerobic, rod-shaped, non-motile strains (DC2W T , DC25W T , and LKC2W) were isolated from streams in China. Comparisons based on the 16S rRNA gene sequences showed that these three strains share 16S rRNA gene sequence similarity values over 97.0 % with the species of genus Arcicella . There was confusion due to the fact that all species of genera Flectobacillus , Aquirufa , and Sandaracinomonas show 16S rRNA gene sequence similarity of over 90.0 % to the above three strains, but the genus Flectobacillus belongs to the family Spirosomataceae and the genera Aquirufa and Sandaracinomonas belong to the family Cytophagaceae . Observing the phylogenetic trees, strains DC2W T , DC25W T , and LKC2W cluster closely with the species of genus Arcicella , but some species within the families Spirosomataceae and Cytophagaceae are not monophyletic. The phylogenomic tree also showed a confused phylogenetic relationships among these non-monophyletic species. Combining the phylogenetic relationships and average nucleotide identity values, the current taxonomic status of all the genera within the families Spirosomataceae and Cytophagaceae were re-examined. The genera ' Chryseosolibacter ', ' Dawidia ', and Chryseotalea should belong to the new family Chryseotaleaceae fam. nov., the genera Arcicella , Flectobacillus , Pseudarcicella , Aquirufa , and Sandaracinomonas should belong to the new family Flectobacillaceae fam. nov., the genera Fluviimonas , Taeseokella , Arcticibacterium , Emticicia , Jiulongibacter , Marinilongibacter , Lacihabitans , and Leadbetterella should belong to the new family Leadbetterellaceae fam. nov., the genus Litoribacter should be reassigned to the family Cyclobacteriaceae , and the genera Arundinibacter and Tellurirhabdus should be reassigned to the family Spirosomataceae . Strains DC2W T and DC25W T are reported to represent two novel species of the genus Arcicella , for which the names Arcicella gelida sp. nov. (type strain DC2W T =GDMCC 1.3209 T =KCTC 92559 T ) and Arcicella lustrica sp. nov. (type strain DC25W T =GDMCC 1.3210 T =KCTC 92557 T ) are proposed.

Karst mountainous areas in Southwest China, the world's largest bare karst area, are faced with growing water shortages. Rainwater harvesting plays an important role in alleviating water shortage. However, there remains a substantial gap in the research regarding the water quality of tanks. Water samples were seasonally collected from ten tanks to investigate the physicochemical properties, microbial communities, and their key influencing factors. The result showed that pH, turbidity, chroma, DOC, and COD Mn exceeded drinking water guidelines. The alkaline pH value and the deterioration of sensory properties was the main feature of tank water, from which the over-standard rate of the uncleaned water tanks was higher. Moreover, principal component analyses suggested that tank water quality was influenced by human activities, catchment areas, and material cycling processes within the tanks, of which in-tank microbial activities were the most important driving factors in water quality variation. Proteobacteria, Actinobacteria, Bacteroidetes, Cyanobacteria, Firmicutes, and Verrucomicrobia were the predominant bacterial phyla in water tanks. Acinetobacter, Cyanobium-PCC-6307, CL500-29-marine-group, Candidatus-Aquiluna, and Exiguobacterium were the most abundant genera. The bacterial communities were significantly affected by the management practices. Higher relative abundance of Cyanobacteria and lower relative abundance of Proteobacteria was detected in the uncleaned tanks, which was a sign of tank water quality deterioration. The microbial community structure was closely related to the environmental factors. There was evidence that the water quality was affected by the existence of a microecosystem dominated by photosynthetic microorganisms in the water tanks. In addition, Acinetobacter, Enterobacter, Pseudomonas, and Legionella identified as the potential opportunistic pathogenic genera were frequently detected but the relative abundances except Acinetobacter were low in the tanks. Overall, our findings indicated that management style influences water quality and bacterial communities of tank water., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Scylla paramamosain is a commercially important mud crab. The microbiota is a community that inhabits the crab intestine, and is important for physiological functional and host health. Results: Proteobacteria, Firmicutes, Bacteroidetes, Tenericutes, Spirochaetae and Fusobacteria were the dominant phyla of the 36 representative phyla. Eleven genera of the 820 representative genera were considered as core gut microbiota and were distributed in the five dominant phyla. The core genus of the Proteobacteria included Arcobacter, Photobacterium, Vibrio, Shewanella and Desulfovibrio. The other four phyla contained one or two genera. Male and female crab samples had two different core genera, (male samples: Psychrilyobacter & Lactococcus; female samples: Clostridium_sensu_stricto_11 and Candidatus_Bacilloplasma). Conclusions: This is the first time core intestinal microbiota have been identified in crab from nine coastal regions of southern China. This study provides sequencing data related to the gut microbiota of S. paramamosain, and may contribute to probiotic development for S. paramamosain aquaculture industries. [ABSTRACT FROM AUTHOR]

Coastal wetlands are undergoing substantial transformations globally as a result of increased human activities. However, compared to other ecosystems, diversity and functional characteristics of microbial communities in reclaimed coastal wetlands are not well studied compared to other ecosystems. This is important because it is known that microorganisms can play a crucial role in biogeochemical cycling within coastal wetland ecosystems. Hence, this study utilized the high-throughput sequencing technique to investigate the structure and assembly processes of microbial communities in reclaimed coastal wetlands. The results revealed a substantial change in soil properties following coastal wetland reclamation. Remarkably, the reclaimed soil exhibited significantly lower pH, soil organic carbon (SOC), and total salinity (TS) values (p < 0.05). The dominant phyla included Proteobacteria, Chloroflexi, Bacteroidetes, Acidobacteria, and Planctomycetes among study sites. However, the relative abundance of Proteobacteria increased from un-reclaimed coastal wetlands to reclaimed ones. The Proteobacteria, Chloroflexi, and Acidobacteria showed higher relative abundance in vegetated soil compared to bare soil, while Bacteroidetes and Planctomycetes exhibited the opposite trend. Notably, vegetation types exerted the strongest influence on microbial diversity, surpassing the effects of soil types and depth (F = 34.49, p < 0.001; F = 25.49, p < 0.001; F = 3.173, p < 0.078, respectively). Stochastic assembly processes dominated in un-reclaimed soil, whereas deterministic processes governed the assembly in artificial sea embankment wetlands (SEW). The presence of Spartina alterniflora in all soil types (except SEW soils) indicated stochastic assembly, while Phragmites australis in reclaimed soils pointed toward deterministic microbial assembly. Furthermore, environmental factors such as pH, soil water content (SWC), SOC, total carbon (TC), total nitrogen (TN), total phosphorus (TP), NH 4 + -N, vegetation types, soil depth, and geographic distance exhibited significant effects on microbial beta diversity indices. Co-occurrence network analysis revealed a stronger association between taxa in SEW compared to land reclaimed from wetlands (LRW) and natural coastal wetlands (NCW). The bottom soil layer exhibited more complex network interactions than the topsoil layer. Besides soil parameters, reclamation and varieties of vegetation were also substantial factors influencing the composition, diversity, and assembly processes of microbial communities in coastal wetlands., Competing Interests: Declaration of competing interest The 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 © 2023 Elsevier B.V. All rights reserved.)

Two novel bacterial strains, designated as SYSU D00344 T and SYSU D00433 T , were isolated from soil of Gurbantunggut Desert in Xinjiang, north-west PR China. Cells of both strains were Gram-stain-negative, aerobic, short-rod-shaped, catalase-positive and non-motile. Oxidase activities of SYSU D00344 T and SYSU D00433 T were negative and positive, respectively. Optimal growth occurred at 30 °C, with 0-0.5 % (w/v) NaCl and at pH 7.0. The results of phylogenetic analysis of 16S rRNA gene sequences indicated that they represented members of the genus Rufibacter and were closely related to Rufibacter hautae NBS58-1 T . The results of phylogenomic analysis indicated that the two strains formed two independent and robust branches distinct from all reference type strains. The analyses of average nucleotide identity (ANI), digital DNA-DNA hybridisation (dDDH) values and 16S rRNA gene similarities between the two strains and their relatives further demonstrated that SYSU D00344 T and SYSU D00433 T represented two different novel genospecies. The polar lipids consisted of phosphatidylethanolamine, one unidentified glycolipid, two unidentified aminophospholipids, and two or four unidentified lipids. MK-7 was the only respiratory quinone. The major fatty acids (>10 %) for both strains were identified as iso-C 15 : 0 , anteiso-C 15 : 0 and summed feature 3 (C 16 : 1 ω7 c and/or C 16 : 1 ω6 c ), as well as summed feature 4 (anteiso-C 17 : 1 B and/or iso-C 17 : 1 I) for SYSU D00344 T and C 16 : 1 ω5 c for SYSU D00433 T . On the basis of the phylogenetic, phenotypic, chemotaxonomic and genotypic characteristics, we propose Rufibacter roseolus sp. nov. and Rufibacter aurantiacus sp. nov. as two novel species in the genus Rufibacter . The type strains are SYSU D00344 T (=CGMCC 1.8625 T =MCCC 1K04971 T =KCTC 82274 T ) and SYSU D00433 T (=CGMCC 1.8617 T =MCCC 1K04982 T =KCTC 82277 T ), respectively.

Background: Gut microbiota plays a significant role in host survival, health, and diseases; however, compared to other livestock, research on the gut microbiome of donkeys is limited., Results: In this study, a total of 30 donkey samples of rectal contents from six regions, including Shigatse, Changdu, Yunnan, Xinjiang, Qinghai, and Dezhou, were collected for metagenomic sequencing. The results of the species annotation revealed that the dominant phyla were Firmicutes and Bacteroidetes, and the dominant genera were Bacteroides, unclassified&#95;o&#95;Clostridiales (short for Clostridiales) and unclassified&#95;f&#95;Lachnospiraceae (short for Lachnospiraceae). The dominant phyla, genera and key discriminators were Bacteroidetes, Clostridiales and Bacteroidetes in Tibet donkeys (Shigatse); Firmicutes, Clostridiales and Clostridiales in Tibet donkeys (Changdu); Firmicutes, Fibrobacter and Tenericutes in Qinghai donkeys; Firmicutes, Clostridiales and Negativicutes in Yunnan donkeys; Firmicutes, Fibrobacter and Fibrobacteres in Xinjiang donkeys; Firmicutes, Clostridiales and Firmicutes in Dezhou donkeys. In the functional annotation, it was mainly enriched in the glycolysis and gluconeogenesis of carbohydrate metabolism, and the abundance was the highest in Dezhou donkeys. These results combined with altitude correlation analysis demonstrated that donkeys in the Dezhou region exhibited strong glucose-conversion ability, those in the Shigatse region exhibited strong glucose metabolism and utilization ability, those in the Changdu region exhibited a strong microbial metabolic function, and those in the Xinjiang region exhibited the strongest ability to decompose cellulose and hemicellulose., Conclusion: According to published literature, this is the first study to construct a dataset with multi-regional donkey breeds. Our study revealed the differences in the composition and function of gut microbes in donkeys from different geographic regions and environmental settings and is valuable for donkey gut microbiome research., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Particle-attached (PA) and free-living (FL) bacterial communities play essential roles in the biogeochemical cycling of essential nutrients in aquatic environments. However, little is known about the factors that drive the differentiation of bacterial lifestyles, especially in flooding lake systems. Here we assessed the compositional and functional similarities between the FL and PA bacterial fractions in a typical flooding lake-the Poyang Lake (PYL) of China. The results revealed that PA communities had significantly different compositions and functions from FL communities in every hydrological period, and the diversity of both PA and FL communities was affected mainly by the water regime rather than bacterial lifestyles. PA communities were more diverse and enriched with Proteobacteria and Bacteroidetes, while FL communities had more Actinobacteria. There was a higher abundance of photosynthetic and nitrogen-cycling bacterial groups in PA communities, but a higher abundance of members involved in hydrocarbon degradation, aromatic hydrocarbon degradation, and methylotrophy in FL communities. Water properties (e.g., temperature, pH, total phosphorus) significantly regulated the lifestyle variations of PA and FL bacteria in PYL. Collectively, our results have demonstrated a clear ecological differentiation of PA and FL bacterial communities in flooding lakes, suggesting that the connectivity between FL and PA bacterial fractions is water property-related rather than water regime-related., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Snub-nosed monkeys are highly endangered primates and their population continues to decline with the habitat fragmentation. Artificial feeding and breeding is an important auxiliary conservation strategy. Studies have shown that changes and imbalances in the gut microbiota often cause gastrointestinal problems in captive snub-nosed monkeys. Here, we compare the gut microbiota composition, diversity, and predicted metabolic function of three endangered species of snub-nosed monkeys (Rhinopithecus bieti, R. brelichi, and R. roxellana) under the same captive conditions to further our understanding of the microbiota of these endangered primates and inform captive conservation strategies. 16 S rRNA gene sequencing was performed on fecal samples from 15 individuals (R. bieti N = 5, R. brelichi N = 5, R. roxellana N = 5)., Results: The results showed that the three Rhinopithecus species shared 24.70% of their amplicon sequence variants (ASVs), indicating that the composition of the gut microbiota varied among the three Rhinopithecus species. The phyla Firmicutes and Bacteroidetes represented 69.74% and 18.45% of the core microbiota. In particular, analysis of microbiota diversity and predicted metabolic function revealed a profound impact of host species on the gut microbiota. At the genus level, significant enrichment of cellulolytic genera including Rikenellaceae RC9 gut group, Ruminococcus, Christensenellaceae R7 group, UCG 004 from Erysipelatoclostridiaceae, and UCG 002 and UCG 005 from Oscillospiraceae, and carbohydrate metabolism including propionate and butyrate metabolic pathways in the gut of R. bieti indicated that R. bieti potentially has a stronger ability to use plant fibers as energy substances. Bacteroides, unclassified Muribaculaceae, Treponema, and unclassified Eubacterium coprostanoligenes group were significantly enriched in R. brelichi. Prevotella 9, unclassified Lachnospiraceae, and unclassified UCG 010 from Oscillospirales UCG 010 were significantly enriched in R. roxellana. Among the predicted secondary metabolic pathways, the glycan biosynthesis and metabolism had significantly higher relative abundance in the gut of R. brelichi and R. roxellana than in the gut of R. bieti. The above results suggest that different Rhinopithecus species may have different strategies for carbohydrate metabolism. The Principal coordinate analysis (PCoA) and Unweighted pair-group method with arithmetic mean (UPGMA) clustering tree revealed fewer differences between the gut microbiota of R. brelichi and R. roxellana. Correspondingly, no differences were detected in the relative abundances of functional genes between the two Rhinopithecus species., Conclusion: Taken together, the study highlights that host species have an effect on the composition and function of the gut microbiota of snub-nosed monkeys. Therefore, the host species should be considered when developing nutritional strategies and investigating the effects of niche on the gut microbiota of snub-nosed monkeys., (© 2023. The Author(s).)

The gut microbiota promotes host health by maintaining homeostasis and enhancing digestive efficiency. The gut microflora in wild birds affects host physiological characteristics, nutritional status, and stress response. The relict gull ( Larus Relictus, a Chinese national first-class protected species) and the black-necked grebe ( Podiceps Nigricollis , a secondary protected species) bred in the Ordos Relic Gull National Nature Reserve share similar feeding habits and living environments but are distantly related genetically. To explore the composition and differences in the gut microbiota of these two key protected avian species in Erdos Relic Gull National Nature Reserve and provide a basis for their protection, 16S rRNA gene high-throughput sequencing was performed and the gut microbial diversity and composition of the relict gull ( L. Relictus ) and black-necked grebe ( P. Nigricollis ) was characterized. In total, 445 OTUs (operational taxonomic units) were identified and classified into 15 phyla, 22 classes, 64 orders, 126 families, and 249 genera. Alpha diversity analysis indicates that the gut microbial richness of the relict gull is significantly lower than that of the black-necked grebe. Gut microbe composition differs significantly between the two species. The most abundant bacterial phyla in these samples were Proteobacteria, Firmicutes, Fusobacteria, and Bacteroidetes. The prominent phylum in the relict gull was Proteobacteria, whereas the prominent phylum in the black-necked grebe was Firmicutes. The average relative abundance of the 17 genera identified was greater than 1%. The dominant genus in the relict gull was Escherichia-Shigella , whereas Halomonas was dominant in the black-necked grebe. Microbial functional analyses indicate that environmental factors exert a greater impact on relict gulls than on black-necked grebes. Compared with the relict gull, the black-necked grebe was able to use food more efficiently to accumulate its nutrient requirements, and the gut of the relict gull harbored more pathogenic bacteria, which may be one reason for the decline in the relict gull population, rendering it an endangered species. This analysis of the gut microbial composition of these two wild avian species in the same breeding grounds is of great significance, offers important guidance for the protection of these two birds, especially relict gulls, and provides a basis for understanding the propagation of related diseases., Competing Interests: The authors declare there are no competing interests., (©2023 Zhao et al.)

Field monitoring revealed that the infection ratio of the bacterial symbiont Cardinium in the whitefly (Bemisia tabaci MED) was relatively low in northern China. However, the role of this symbiont and the symbiont-whitefly-host plant interaction mechanism are poorly understood. We investigated the influence of Cardinium on the competitiveness of the host whitefly and the physiological interaction between the host plants and host whiteflies. Cardinium-infected whiteflies were displaced by uninfected whiteflies after 5 generations, which showed that Cardinium infection reduced whitefly competitiveness. The defense response genes of cotton significantly decreased under infestation by infected whiteflies compared to uninfected whiteflies. The expression of detoxification metabolism genes, especially the uridine 5'-diphospho-glucuronyltransferase and P450 genes, in infected whiteflies significantly decreased. These results demonstrated that Cardinium could inhibit the defense response of the host plant and decrease the detoxification metabolism ability of the host whitefly. The reduced competitiveness of infected whiteflies may be associated with the inhibition of the whitefly detoxification metabolism by Cardinium, resulting in the reduced performance of infected whiteflies. However, Cardinium infection can suppress plant defenses, which may benefit both infected and uninfected whiteflies when they coexist. This research illustrates the symbiont-whitefly-host plant interaction mechanism and the population dynamics of the whitefly., (© 2022 Institute of Zoology, Chinese Academy of Sciences.)

While dam construction supports social and economic development, changes in hydraulic conditions can also affect natural aquatic ecosystems, especially microbial ecosystems. The compositional and functional traits of multi-trophic microbiota can be altered by dam construction, which may result in changes in aquatic predator-prey interactions. To understand this process, we performed a large-scale sampling campaign in the urban reaches of the dam-impacted Yangtze River (1 995 km) and obtained 211 metagenomic datasets and water quality data. We first compared the compositional traits of planktonic microbial communities upstream, downstream, and in a dam reservoir. Results showed that Bacteroidetes (R-strategy) bacteria were more likely to survive upstream, whilst the reservoir and downstream regions were more conducive to the survival of K-strategy bacteria such as Actinobacteria. Eukaryotic predators tended to be enriched upstream, whilst phototrophs tended to be enriched in the reservoir and downstream regions. Based on bipartite networks, we inferred that the potential microbial predator-prey interactions gradually and significantly decreased from upstream to the downstream and dam regions, affecting 56% of keystone microbial species. Remarkably, functional analysis showed that the abundance of the photosynthetic gene psbO was higher in the reservoir and downstream regions, whilst the abundance of the KEGG carbohydrate metabolic pathway was higher upstream. These results indicate that dam construction in the Yangtze River induced planktonic microbial ecosystem transformation from detritus-based food webs to autotroph-based food webs., 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 © 2023 Elsevier Ltd. All rights reserved.)

The study of bacterial community diversity and metabolic function in lake water is of great significance to the healthy development of the urban landscape lake water environment. In this study, Hancheng Lake, Nanhu Lake, Xingqing Lake, and Taohuatan Lake were selected as the study area. Illumina Nova high-throughput sequencing technology was used to study the composition and structure of bacterial communities in four different types of lakes. The correlation between bacterial communities and environmental factors was analyzed using the RDA method. Tax4Fun was used to predict the metabolic function of bacterial communities. The results showed that the diversity of bacterial communities was different in different lakes. The α diversity of Taohuatan Lake was the highest, and that of Xingqing Lake was the lowest. The bacterial community structure of the same lake had a trend of aggregation. The dominant phyla of bacteria in the four lakes were similar, mainly Proteobacteria, Bacteroidetes, and Actinobacteria. The difference was only in the proportion of bacteria. Additionally, the distribution of bacterial communities at the genus level in the four lakes was quite different. The physical and chemical properties of lakes were significantly correlated with bacterial community, and the most critical factor was nitrogen and phosphorus nutrients( P <0.05). Tax4Fun function prediction showed that the metabolic function of bacterial communities in the four lakes was similar, and the relative abundance of amino acid metabolism and carbohydrate metabolism was the highest. In addition, the potential drug-resistant bacterial pollution and the possibility of human infectious diseases were higher. These results are helpful for understanding the current situation of bacteria in urban lakes in Xi'an and providing a theoretical basis for the management and sustainable development of urban lakes.

Florpyrauxifen-benzyl is an herbicide that has been developed in recent years. Its degradation mode in paddy soil environments is not clear. In this study, the degradation dynamics in paddy soil and water were studied by ultrahigh-performance liquid chromatography. Microbial degradation was the main degradation pathway. Using third-generation high-throughput sequencing technology, the changes in the soil bacterial community structure were studied. After 30 days of application, compared with the control group (F0), the abundance of Sphingomonas, Lysobacter, and Flavisolibacter in the recommended and repeated application groups (F1, F5 and F10) increased significantly, and uncultured bacterium and Terrimonas decreased significantly. Compared with the F0 and F1 groups, the species diversity of the F0 and F1 groups showed a significant increase over time. The species diversity of the F5 and F10 groups decreased significantly on Days 5 and 15. On Day 30, the recovery even exceeded that of the control group. Luteimonas and five other genera were positively correlated with herbicide residues, and Pseudolabrys and two other genera were negatively correlated. Repeated application showed a significant effect on the structure of the soil bacterial community, mainly showing a trend of a significant decrease in the initial stage and gradual recovery in the later stage. The results will guide the safe and rational use of florpyrauxifen-benzyl and provide a scientific basis for florpyrauxifen-benzyl dynamic supervision of environmental pollution and protection of black soil in Northeast China., 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 © 2022. Published by Elsevier Inc.)

To understand the relationship between elevation and bacterial communities in wastewater treatment plants (WWTPs), bacterial communities in 21 municipal WWTPs across China, located 9 to 3,660 m above sea level (masl), were investigated by 454 pyrosequencing. A threshold for the association of elevation with bacterial community richness and evenness was observed at approximately 1,200 masl. At lower elevations, both richness and evenness were not significantly associated with elevation. At higher elevations, significant declines with increased elevations were observed for community richness and evenness. The declining evenness trend at the phylum level was reflected by distinct trends in relative abundance for individual bacterial phyla. Betaproteobacteria, Bacteroidetes, and Firmicutes displayed significant increases, while most other phyla showed declines. Spearman correlation analysis indicated that the community richness and evenness at high elevations were more correlated with elevation than with any other single environmental variable. Redundancy analysis indicated that the contribution of elevation to community composition variances increased from 3% at lower elevations to 11% at higher elevations whereas the community composition variance at higher elevations remained much more explained by operational variables (39.2%) than by elevation. The influent total phosphorus concentration, food/microorganism ratio, and treatment process were the three shared dominant contributors to the community composition variance across the whole elevation gradient, followed by effluent ammonia nitrogen and temperature at higher elevations. [ABSTRACT FROM AUTHOR]

We recovered microorganisms from five ice core samples from three glaciers (Puruogangri, Malan, and Dunde) located in the Tibetan Plateau in China and analyzed their small subunit rRNA gene sequences. Most of the bacterial sequences were unknown previously; the most closely related known sequences were from bacteria of the Proteobacteria, Bacteroidetes, and Actinobacteria phyla. Chlorophyta, Streptophyta, Ciliophora, and fungal groups were represented among the 18S rRNA gene sequences that we obtained. The most abundantly represented glacial bacteria were Bacteroidetes, and Chlamydomonas was the predominant eukaryote. Comparative analysis showed that the Bacteroidetes sequences obtained from this study were highly similar to one another but most were only distantly related to previously characterized Bacteroidetes (<92% identity). We propose that our Bacteroidetes sequences represent two novel subgroups: one at the family level and one at the genus level. The unique ice environment and the high abundance of Bacteroidetes, combined with the coexistence of a high abundance of psychrophilic Chlamydomonas, strongly suggests that there is a viable ecosystem on the surface of Tibetan glaciers. Comparisons of microbial community structures in the five ice samples showed distinct differences, likely due to environmental differences in the locations in which the samples were obtained. [ABSTRACT FROM AUTHOR]

A Gram-stain-negative, non-motile, facultatively anaerobic and non-flagellated marine bacterium, designated JC070 T was isolated from the Yongle Blue Hole in the South China Sea. The temperature, pH and NaCl ranges for growth of strain JC070 T were 4-37 °C (optimum, 16 °C), pH 6.0-9.0 (optimum, pH 7.0) and 1.0 -6.0% (w/v; optimum, 3.0%). The predominant isoprenoid quinone of strain JC070 T was identified as menaquinone-7. The dominant fatty acids (>10%) were iso-C 15:0 (59.6%) and iso-C 17:0 3-OH (17.2%). The major polar lipids were aminophospholipid, aminolipid, two unknown phospholipids and two unidentified lipids. The genomic DNA G+C content was determined to be 37.0 mol%. Based on the results of polyphasic analysis, a new species, named Marinifilum caeruleilacunae sp. nov., within the genus Marinifilum was proposed. The type strain is JC070 T (= JCM 39045 T =MCCC 1K03774 T ).

Two Gram-stain negative, facultative anaerobic, oxidase-negative, catalase-positive bacilli, designated as strains TMQ4 T and TMQ2, were isolated from Xiaoshi Island, China, using prey-traps. Growth was observed within the ranges 25-45 °C (optimally at 37 °C), pH 6.5-9.0 (optimally at pH 7.5-8.0) and 1-8% NaCl (optimally at 3-4%, w/v). The draft genome sequences of strains TMQ4 T and TMQ2 contained 184 contigs of 5,609,735 bp with a G+C content of 64.4% and 148 contigs of 5,589,985 bp with a G+C content of 65.0%, respectively. Phylogenetic analysis based on 16S rRNA gene sequences showed that both strains belonged to the genus Lujinxingia with the similarity of 98.9%. The phylogenetic and phylogenomic topologies and analyses demonstrated that both strains clustered together and differentiated from the closest neighbour, Lujinxingia sediminis SEH01 T . Genomic analyses showed that two strains lost the biosynthesis pathway of several chemical compounds. Iso-C 15:0 was contained in the predominant cellular fatty acids in both strains. The major polar lipids of both strains consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, and unidentified lipids; and the respiratory quinone was menaquinone MK-7 for both strains. Both strains predated other bacteria, including Owenweeksia hongkongensis JCM 12287 T and Paraliobacillus ryukyuensis DSM 15140 T , and were lured with one prey Acinetobacter baumannii ATCC 19606 T in prey-trap. Combining genomic analyses, two strains had the predatory indices of 2, similar to representative typical bacterial predators. The physiological, biochemical, and phylogenetic properties suggest that the two strains represent a novel species within the genus Lujinxingia. The name Lujinxingia vulgaris sp. nov. is proposed, with strain TMQ4 T (= KCTC 62851 T  = MCCC 1H00392 T ) as type strain and strain TMQ2 (= KCTC 72,079 = MCCC 1H00381) as reference strain., (© 2021. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Strain CZZ-1 T was isolated from long-term TBBPA-contaminated soil Zaozhuang city, Shandong province, People's Republic of China. CZZ-1 T was pink-pigmented, Gram-stain-negative, rod-shaped, non-motile and aerobic. The 16S rRNA gene analysis indicated that strain CZZ-1 T shows high similarities to Fluviicola taffensis DSM 16823 T (92.6%) and Fluviicola hefeinensis KACC 16597 T (92.5%) and less than 91% sequence similarities to other genus or species in the family Crocinitomicaceae. It was able to grow at 10-37 °C, with 0-6% (w/v) NaCl. It could hydrolyze gelatin, but could not reduce nitrates to nitrites. The predominant fatty acids of strain CZZ-1 T were iso-C 15:0 (51.3%), C 15:0 2-OH (11.0%), iso-C 17:0 3-OH (8.0%), C 14: 0 (7.0%), iso-C 15:1 G (6.8%) and Summed Feature 3 (C 16:1 ω7c and/or C 16:1 ω6c, 4.4%). The polar lipid profile was composed of five unidentified lipids, two unidentified phospholipids, one phosphatidylethanolamine, one unidentified aminolipid and one unidentified glycolipid. The predominant respiratory quinone was MK-6. The genomic DNA G+C content of strain CZZ-1 T was 41.5 mol%. Based on data from phenotypic, chemotaxonomic and genotypic analysis in this study, strain CZZ-1 T represents a novel species in a new genus in the family Crocinitomicaceae, for which the name Taishania pollutisoli gen. nov., sp. nov. is proposed. The type strain is CZZ-1 T (= KCTC 52343 T  = GDMCC 1.2270 T ).

A Gram-stain-negative, aerobic, non-motile, yellow-pigmented rod-shaped and alginate-degrading bacterium, designated B1N29 T , was isolated from the gut of the abalone Haliotis rubra obtained in Weihai, China. Strain B1N29 T was found to grow at 4-35 ℃ (optimum, 25 ℃), at pH 6.5-9.0 (optimum, 7.0-7.5) and in the presence of 0.5-9% (w/v) NaCl (optimum, 2%). Cells were positive for oxidase and catalase activity. The 16S rRNA-based phylogenetic analysis revealed that the nearest phylogenetic neighbors of strain B1N29 T were Tamlana carrageenivorans KCTC 62451 T (98.2%) and Tamlana agarivorans KCTC 22176 T (97.7%). Based on the phylogenomic analysis, the average nucleotide identity (ANI) values between strain B1N29 T and the neighbor strains were 79.2 and 79.0%, respectively; the digital DNA-DNA hybridization (dDDH) values between strain B1N29 T and its two closest neighbors were 22.8 and 23.0%, respectively. Menaquinone-6 (MK-6) was detected as the sole respiratory quinone. The dominant cellular fatty acids were iso-C 15:0 , iso-C 17:0 3-OH, anteiso-C 15:0 and iso-C 15:1 G. The polar lipids included phosphatidylethanolamine, one aminophospholipid, seven aminolipids and five unidentified lipids. Based on the phylogenetic and phenotypic characteristics, strain B1N29 T is considered to represent a novel species of the genus Tamlana, for which the name Tamlana haliotis sp. nov. is proposed. The type strain is B1N29 T (= KCTC 72683 T  = MCCC 1H00394 T ).

• Rumen bacteria community of Tibetan sheep was predominated by phyla Bacteroidetes, Firmicute and Verrucomicrobia at phylum level, as to genus , Rikenellaceae_RC9_gut_group and Prevotella_1 predominated. • Sex and age were two important factors which shaping the rumen bacterial composition of Tibetan sheep as previous reported on mice and human. • Most of predicted function genes significantly enriched in adult female sheep compared with adult male sheep and yearling female sheep, respectively. In this study, 18 Tibetan sheep were assigned into four groups by age and sex, namely young ewes (E1, n = 5), young rams (R1, n = 3), adult ewes (EA, n = 5) and adult rams (RA, n =5) to profile the bacterial composition of Tibetan sheep and to explore the impacts of sex and age on rumen microbiota using high-throughput sequencing method of amplicon of 16S rRNA V3–V4 region. The results indicated that all effective tags for 18 samples were clustered into 5429 OTUs (Operation taxonomic Units, OTUs) with an absolute abundance > 1 at a similarity level > 97%. The rumen bacterial composition of female adult sheep was more diverse than male adult sheep and yearling female sheep. SILVA database was used to annotate taxonomic information for each representative sequence using the RDP classifier, the results showed that Bacteroidetes, Firmicutes, Verrucomicrobia and Proteobacteria were the most dominant phyla, representing 56.68%, 28.81%, 6.71% and 1.73% of reads from all samples on average, respectively. At the genus level, Rikenellaceae_RC9_gut_group , and Prevotella_1 were most abundant with relative abundance of 12.98% and 11.19%, respectively. Relative abundance of Bacteroidetes in EA was greater than RA (p = 0.014), relative abundance of Firmicutes in RA was greater than EA (p < 0.001), and the relative abundance of Spirochaetae in E1 was greater than R1 (p = 0.038). Shifting genera between the sexes belonged to Order Bacteroidales and Clostridiales , both changed substantially across sex in adult sheep (p < 0.01). The abundance of Bacteroidetes in female sheep and Firmicutes and Planctomycetes in male sheep significantly increased with age (p < 0.05), while the abundance of Spirochaetae in female sheep and Cyanobacteria in male sheep decreased with age (p < 0.05). Shifting genera between age groups belonged to order Bacteroidales and Clostridial. The abundance of order Bacteroidales in female sheep increased with age (p = 0.046), and the abundance of order Clostridiales in male sheep increased with age (p = 0.006), while it decreased with age in female sheep (p = 0.030). In summary, this study profiled the bacterial composition characteristics of Tibetan sheep and concluded that physiological factors, e.g. sex and age, shaped the bacterial composition, which expands our knowledge of the rumen of ruminant animals residing on the Qinghai-Tibetan Plateau. [ABSTRACT FROM AUTHOR]

Objective: To assess the bacterial characteristics associated with intra-oral halitosis among Chinese preschool children., Methods: An epidemiological study was conducted among 273 preschool children (aged 3-4 years) in Shanghai, China, followed by the collection of 16 samples from the tongue coating of caries-free healthy and halitosis participants. The characterization of associated microbial communities was performed using 16S rRNA gene sequencing on the MiSeq., Results: Halitosis was observed in 13.2% of the preschool children. No significant difference in terms of microbial diversity (p > .05) was detected in the control and halitosis groups. The dominant bacterial genera observed in both groups included Prevotella, Veillonella, Streptococcus, Neisseria, Actinomyces, Haemophilus, and Leptotrichia. The relative proportions of thirteen species (including Leptotrichia sp. HMT&#95;417, Prevotella Pallens, and Alloprevotella rava) were significantly higher in the halitosis group compared with the control group, whereas the distribution of seventeen species from genera Streptococcus, Gemella, and Kingella showed a higher abundance in the control group. Further investigation of interactions among species demonstrated obvious differences in two groups, indicating that various microorganisms interact to produce halitosis in preschool children., Conclusions: Overall, halitosis is associated with multi-microbial mutual interactions. The oral flora microorganisms may exert potentiating or inhibiting effects on each other., (© 2020 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd. All rights reserved.)

Bacterial communities play an important role in the biogeochemical cycle in reservoir ecosystems. However, the dynamic changes in both planktonic and sediment bacterial communities in a highly regulated dam reservoir remain unclear. This study investigated the temporal distribution patterns of bacterial communities in a transition section of the Three Gorges Reservoir (TGR) using Illumina MiSeq sequencing. Results suggested that in comparison to the planktonic bacteria, sediment bacteria contributed more to the reservoir microbial communities, accounting for 97% of the 7434 OTUs. The Shannon diversity index in the water (3.22~5.68) was generally lower than that in the sediment (6.72~7.56). In the high water level period (January and March), Proteobacteria, Actinobacteria, Cyanobacteria, and Firmicutes were the most abundant phyla, whereas in the low water level period (May, July, and September), the dominant phyla were Proteobacteria, Actinobacteria, and Bacteroidetes. Sediment samples were dominated by Proteobacteria, Chloroflexi, and Acidobacteria. Principal coordinate analysis of the bacterioplankton communities showed greater sensitivity to monthly changes than that of the sediment bacterial communities. Network analysis suggested that in comparison to planktonic bacterial communities, sediment bacterial communities were more complex and stable. The linear relationship between the CH 4 /CO 2 ratio, water level, and relative abundance of methanotrophs highlighted the potential methane-oxidizing process in the mid-part of the TGR. Moreover, the potential impact of dam regulation on the bacterial communities was revealed by the significant relationship between abundant phyla and the inflow of the TGR. KEY POINTS: • Bacterioplankton communities showed great sensitivity to monthly changes. • Potential methane-oxidizing process was revealed in this representative area. • Water inflow regulated by dam has significant effects on dominant bacterioplankton.

Microorganisms have important ecological functions in ecosystems. Reseeding is considered as one of the main strategies for preventing grassland degradation in China. However, the response of soil microbial community and diversity to reseeding grassland (RG) and natural grassland (NG) remains unclear, especially in the Songnen Meadow. In this study, the soil microbial community compositions of two vegetation restoration types (RG vs NG) were analyzed using a high-throughput sequencing technique. A total of 23,142 microbial OTUs were detected, phylogenetically derived from 11 known bacterial phyla. Soil advantage categories included Proteobacteria, Acidobacteria, Actinobacteria, and Bacteroidetes, which together accounted for > 78% of the all phyla in vegetation restoration. The soil microbial diversity was higher in RG than in NG. Two types of vegetation restoration had significantly different characteristics of soil microbial community (P < 0.001). Based on a molecular ecological network analysis, we found that the network in RG had a longer average path distance and modularity than in NG network, making it more resilient to environment changes. Meanwhile, the results of the canonical correspondence analysis and molecular ecological network analysis showed that soil pH (6.34 ± 0.35 in RG and 7.26 ± 0.28 in NG) was the main factor affecting soil microbial community structure, followed by soil moisture (SM) in the Songnen meadow, China. Besides, soil microbial community characteristics can vary significantly in different vegetation restoration. Thus, we suggested that it was necessary and reasonable for this area to popularize reseeding grassland in the future.

Strains J15B81-2 T and J15B91 T were isolated from a sediment sample collected from the South China Sea. Cells of both strains were observed to be rod-shaped, non-gliding, Gram-stain-negative, yellow-pigmented, facultatively anaerobic, catalase-positive, oxidase-negative and showing optimum growth at 30 °C. Strains J15B81-2 T and J15B91 T could tolerate up to 9 and 10  % (w/v) NaCl concentration and grow at pH 6.5-9.5 and 6.0-9.0, respectively. The strains shared 97.4 % 16S rRNA gene sequence similarity to each other but were identified as two distinct species based on 81.1-85.8 % ANIb and 31.5 % dDDH values calculated using whole genome sequences. Strains J15B81-2 T and J15B91 T shared highest 16S rRNA gene sequence similarity to Salinimicrobium xinjiangense CGMCC 1.12522 T (98.4 %) and Salinimicrobium sediminis CGMCC 1.12641 T (98.0 %), respectively. Among species with validly published names, S. sediminis CGMCC 1.12641 T shared close genetic relatedness with strains J15B81-2 T [85.1-85.3% average nucleotide identity based on blastBlast+ (ANIb) and 30.6 % digital DNA-DNA hybridization (dDDH)] and J15B91 T (76.6-79.1 % ANIb and 21.5 % dDDH). The major fatty acid of strains J15B81-2 T and J15B91 T were identified as iso-C 15 : 0 and iso-C 16 : 0 , respectively, and the major polar lipids of the two strains consisted of phosphatidylethanolamine, one unidentified phospholipid, one unidentified aminolipid and one unidentified lipid. The strains contained MK-6 as their predominant menaquinone. The genomic G+C contents of strains J15B81-2 T and J15B91 T were determined to be 41.7 and 41.8 mol %, respectively. Both strains are considered to represent two novel species of the genus Salinimicrobium and the names Salinimicrobium nanhaiense sp. nov. and Salinimicrobium oceani sp. nov. are proposed for strains J15B81-2 T (=KCTC 72867 T =MCCC 1H00410 T ) and J15B91 T (=KCTC 72869 T =MCCC 1H00411 T ), respectively.

Ambient particle (PM 2.5 ) samples were collected in three East Asian cities (Beijing, China; Seoul, South Korea; Nagasaki, Japan) from December 2014 to November 2015 to quantitatively investigate airborne bacteria at the phylum level. Proteobacteria, Firmicutes, Actinobacteria, Bacteroidetes, and Cyanobacteria represented the top five airborne bacterial phyla in all three cities. The most dominant airborne phylum, Proteobacteria, was more prevalent during the winter (at rates of 67.2%, 79.9%, and 87.0% for Beijing, Seoul, and Nagasaki, respectively). Correlations among airborne bacteria and environmental factors including PM 2.5 , its major chemical constituents, and meteorological factors were calculated. Temperature correlated negatively with Proteobacteria but positively with Firmicutes and Bacteroidetes. The abundance of Cyanobacteria correlated positively with particulate NO 3 - and SO 4 2- levels in Beijing (R = 0.46 and R = 0.35 for NO 3 - and SO 4 2- , respectively) but negatively in Seoul (R = -0.14 and R = -0.19 for NO 3 - and SO 4 2- , respectively) and Nagasaki (R = -0.05 and R = -0.03 for NO 3 - and SO 4 2- , respectively). Backward trajectory analysis was applied for 72 h and three clusters were classified in each city. Five dominant bacteria and other bacterial groups showed significant differences (p < 0.05) in local clustering, as compared to the long-range transport clusters from Beijing. The proportions of the five bacterial phyla in Seoul were significantly different in each cluster. A local cluster in Nagasaki had higher ratios of all major airborne bacterial phyla, except Proteobacteria., 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 © 2020 Elsevier Ltd. All rights reserved.)

Strains of Echinicola , thought to play vital roles in the environment for their high enzyme production capacity during decomposition of polysaccharides, are ubiquitous in hypersaline environments. A Gram-negative, non-spore forming, gliding, aerobic bacterial strain, designated LN3S3 T , was isolated from alkaline saline soil sampled in Tumd Right Banner, Inner Mongolia, northern PR China. Strain LN3S3 T grew at 10-40 °C (optimum, 30 °C), pH 5.0-9.0 (optimum, pH 8.0) and with 0-12.5 % NaCl (optimum, 2.0 %). A phylogenetic tree based on the 16S rRNA gene sequences showed that strain LN3S3 T clustered with Echinicola rosea JL3085 T and Echinicola strongylocentroti MEBiC08714 T , sharing 97.0, 96.7 and <96.50 % of 16S rRNA gene sequence similarities to E. rosea JL3085 T , E. strongylocentroti MEBiC08714 T and all other type strains. MK-7 was the major respiratory quinone, while phosphatidylethanolamine, two unidentified phospholipids, an unidentified aminophospholipid, an unidentified lipid and two unidentified aminolipids were the major polar lipids. Its major cellular fatty acids were iso-C 15 : 0 , anteiso-C 15 : 0 and summed feature 3 (C 16 : 1   ω7 c and/or C 16 : 1   ω6 c ). The genome consisted of a circular 5 550 304 bp long chromosome with a DNA G + C content of 44.0 mol%. The average nucleotide identity (ANI), average amino acid identity (AAI) and digital DNA-DNA hybridization (dDDH) values of strain LN3S3 T to E. rosea JL3085 T and E. strongylocentroti MEBiC08714 T were 82.5 and 81.5 %, 87.5 and 86.0 %, and 39.1 and 35.1 %, respectively. Based on physiological, genotypic and phylogenetic analyses, strain LN3S3 T could be discriminated from its phylogenetic relatives. Echinicola soli sp. nov. is therefore proposed with strain LN3S3 T (=CGMCC 1.17081 T =KCTC 72458 T ) as the type strain.

A Gram-negative, strictly aerobic, gliding motility, none-spore forming, yellow, rods bacterial strain, designated XS-5 T , was isolated from rhizosphere soil of Suaeda salsa , in Tumd Right Banner, Inner Mongolia, PR China. A phylogenetic tree based on the 16S rRNA gene sequences and the phylogenomic tree both showed that strain XS-5 T clustered with Flavobacterium beibuense F44-8 T (shared 97.2 % of 16S rRNA gene similarity) and Flavobacterium rakeshii FCS-5 T (97.6 %), and shared <96.0 % of 16S rRNA gene similarities with all other type strains. Strain XS-5 T contained MK-6 as the major respiratory quinone. Its major polar lipids were phosphatidylethanolamine, an unidentified aminolipid and an unidentified lipid; and the major fatty acids were iso-C 15 : 0 , iso-C 17 : 0 3-OH, C 16 : 0 , iso-C 15 : 0 3-OH, Summed feature 3 (iso-C 15 : 0 2-OH and/or C 16 : 1   ω 7c ), and Summed feature 9 (iso-C 17 : 1  ω 9 c and/or C 16 : 0 10-methyl). The genome consisted of a 3 985 855 bp circular chromosome, with a G+C content of 37.9 mol%, predicting 3616 coding sequences genes, 45 tRNA genes and three rRNA operons. The average nucleotide identity, amino acid identity and digital DNA-DNA hybridization values of strain XS-5 T to F. beibuense F44-8 T and F. rakeshii FCS-5 T were 79.2 and 79.2 %, 81.7 and 81.6 %, 22.3 and 22.2 %, respectively. The results of phylogenetic, physiological and biochemical tests allowed the discrimination of strain XS-5 T from its phylogenetic relatives. Flavobacterium alkalisoli sp. nov. is therefore proposed with strain XS-5 T (=CGMCC 1.17077 T =KCTC 72459 T ) as the type strain.

Numerous genetic markers have been developed to establish microbial source tracking (MST) assays in the last decade. However, the selection of suitable markers is challenging due to a lack of understanding of fundamental factors such as sensitivity, specificity, and concentration in target/nontarget hosts, especially in East Asia. In this study, a total of 506 faecal samples comprised of human and 12 nonhuman hosts were collected from 28 cities across China and tested for marker performance characteristics. We firstly tested 40 host-associated markers based on a binary (presence/absence) criterion. Here, 15 markers (7 human-associated, 4 pig-associated, 3 ruminant-associated, and 1 poultry-associated) showed potential applicability in our study area. The selected 15 markers were then tested using qualitative and quantitative methods to characterise their performance. Overall, Bacteroidales markers presented higher sensitivity and concentrations in target samples compared to other bacterial or viral markers, but their specificity was low. Among nontarget samples, pets accounted for 43.7% and 35.7% of cross-reactivity with human-associated and poultry-associated markers, respectively. Noncommon animals, including horse and donkey, contributed 61.3% of cross-reactivity with ruminant-associated markers. When considering the quantitative distribution of markers, their concentration in nontarget samples were 1-3 orders of magnitude lower than in target samples. Moreover, a novel classification method was proposed to classify the nontarget hosts into four groups spanning "no cross-reactivity", "weak cross-reactivity", "moderate cross-reactivity", and "strong cross-reactivity" animal hosts. There were 77.9% nontarget samples identified as no cross-reactivity and weak cross-reactivity hosts, suggesting that these nontarget hosts produce little interference for corresponding markers. Our findings elucidate the performance of host-associated markers around China in a qualitative and quantitative manner, and reveal the interference degree of cross-reactivity from nontarget animals to genetic markers, which will facilitate tracking of multiple faecal pollution sources and planning timely remedial strategies in China., 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 © 2020 Elsevier Ltd. All rights reserved.)

A novel rod-shaped and Gram-stain-negative bacterium, designated strain RZ05 T , was isolated from a sand sample collected from the intertidal zone of the Yellow Sea, PR China. Results of phylogenetic analysis based on 16S rRNA gene sequences revealed that strain RZ05 T clusters within the genus Maribacter , a member of the family Flavobacteriaceae , and has the highest sequence similarity to Maribacter polysiphoniae KCTC 22021 T (97.8 %), followed by Maribacter arenosus KCTC 52191 T (97.2 %). Cells of this strain were observed to be aerobic, oxidase- and catalase-positive, motile by gliding and formed yellow colonies. Growth occurred at 7-40 °C (optimum, 30 °C), at pH 6.5-9.5 (optimum, pH 7.0) and with 0.5-6 % (optimum, 2 %) NaCl. Its polar lipid profile included phosphatidylethanolamine, two unidentified glycolipids, one unidentified aminolipid and four unidentified lipids. The major cellular fatty acids were iso-C 15 : 0 , iso-C 15 : 1 G, iso-C 17 : 0 3-OH, iso-C 16 : 0 3-OH, iso-C 15 : 0 3-OH, summed feature 9 (10-methyl C 16 : 0 /iso-C 17 : 1   ω9 c ) and summed feature 3 (iso-C 15 : 0 2-OH/C 16 : 1   ω7 c /C 16 : 1   ω6 c ). The only respiratory quinone was menaquinone 6 (MK-6). The genome of strain RZ05 T was 4.65 Mbp with a G+C content of 38.9 mol%. The average nucleotide identity and in silico DNA-DNA hybridization values between strain RZ05 T and its most closely related type strain M. polysiphoniae KCTC 22021 T were 80.3 and 26.3  %, respectively. The results of phylogenetic, phenotypic and chemotaxonomic analyses indicated that strain RZ05 T represents a novel species of the genus Maribacter , for which the name Maribacter luteus sp. nov. is proposed. The type strain is RZ05 T (=KCTC 62834 T =MCCC 1K03617 T ).

Bacterial communities play crucial roles in the biogeochemical cycle of the surface sediments of freshwater lakes, but previous studies on bacterial community changes in this habitat have mostly been based on the total bacterial community (DNA level), while an exploration of the active microbiota at the RNA level has been lacking. Herein, we analysed the bacterial communities in the surface sediments of Lake Taihu at the DNA and RNA levels. Using MiSeq sequencing and real-time quantification, we found that the sequencing and quantitative results obtained at the RNA level compared with the DNA level were more accurate in responding to the spatiotemporal dynamic changes of the bacterial community. Although both sequencing methods indicated that Proteobacteria, Chloroflexi, Acidobacteria, Nitrospirae, Bacteroidetes and Actinobacteria were the dominant phyla, the co-occurrence network at the RNA level could better reflect the close relationship between microorganisms in the surface sediment. Additionally, further analysis showed that Prochlorococcus and Microcystis were the most relevant and dominant genera of Cyanobacteria in the total and active bacterial communities, respectively; our results also demonstrated that the analysis of Cyanobacteria-related groups at the RNA level was more 'informative'., (© FEMS 2020.)

Drinking water purification and distribution processes shape the bacterial community in tap water; however, this study calls attention to the impact of source water on tap water bacterial community. Herein, paired source and tap water samples were collected from 46 drinking water supply systems in different watersheds across China, and high-throughput sequencing delineated that bacterial richness and diversity decreased and biogeographical distribution pattern weakened in tap water compared to source water. Despite the great changes of bacteria from source to tap, Bayesian-based SourceTracker analysis still verified that the proportional contributions of source water to shaping the tap water bacterial community ranged from 0% to 92.8% (49.73% ± 30.22% on average). This indelible contribution was further confirmed by the Mantel test (P < 0.001), Procrustes test (P < 0.001) and variance partition analysis, which showed that the source water together with geographical location explained 40.11% of tap water bacterial community variation. To explore the potential reasons that explain the great differences in the impact of source water among different samples, the universal shift pattern of bacterial communities from source to tap was summarized as a classification of dominant bacterial taxa: "sensitive taxa" versus "resistant taxa". The taxa including Planctomycetes, Verrucomicrobia, Acidobacteria, Chloroflexi, and δ-Proteobacteria could act as biomarkers to distinguish samples between source and tap water, and were classified as sensitive taxa. In contrast, α-Proteobacteria, β-Proteobacteria, γ-Proteobacteria, Actinobacteria, Firmicutes, Bacteroidetes, and Cyanobacteria were classified as resistant taxa. The abundance of sensitive taxa was negatively correlated with the SourceTracker proportion, while the abundance of resistant taxa was positively correlated with the SourceTracker proportion (P < 0.01). Thus, variation in source water bacterial community could be responsible for the degree of impact on tap water. Our findings give notice that the impact of source water microbiomes must be taken more seriously, and sufficient source water protection and engineering control strategies should be implemented to prevent the biological consequences of source water on tap water., 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 © 2020 Elsevier Ltd. All rights reserved.)

To correctly assess and properly manage the public health risks associated with exposure to contaminated water, it is necessary to identify the source of fecal pollution in a watershed. In this study, we evaluated the efficacy of our two previously developed real time-quantitative PCR (qPCR) assays for the detection of swine-associated Bacteroidales genetic markers (gene 1-38, gene 3-53) in the Yangtze Delta watershed of southeastern China. The results indicated that the gene 1-38 and 3-53 markers exhibited high accuracy (92.5%, 91.7% conditional probability, respectively) in detecting Bacteroidales spp. in water samples. According to binary logistic regression (BLR), these two swine-associated markers were well correlated (P < 0.05) with fecal indicators (Escherichia coli and Enterococci spp.) and zoonotic pathogens (E. coli O157: H7, Salmonella spp. and Campylobacter spp.) in water samples. In contrast, concentrations of conventional fecal indicator bacteria (FIB) were not correlated with zoonotic pathogens, suggesting that they are noneffective at detecting fecal pollution events. Collectively, the results obtained in this study demonstrated that a swine-targeted qPCR assay based on two Bacteroidales genes markers (gene 1-38, gene 3-53) could be a useful tool in determining the swine-associated impacts of fecal contamination in a watershed., (Copyright © 2019. Published by Elsevier B.V.)

Freshwater ecosystems are undergoing extensive human disturbance of dam construction which form large amounts of reservoirs and lead to dramatic changes in hydraulic conditions. Bacterioplankton are key component of aquatic ecosystems. Investigation on their taxonomic compositions and associated functions responded to reservoir operation is essential to understand the ecological consequence of dam construction. In this study, we use the Three Gorges Reservoir as a model system. High-throughput sequencing is used to investigate the bacterioplankton community composition, and the bioinformatic tool of Tax4Fun is applied to predict the potential metabolic functions responded to reservoir impoundment. Results show that the taxonomic communities of bacterioplankton are significantly impacted by impoundment. The dominant group of Actinobacteria which accounts for 17.0%-58.1% of the retrieved sequences significantly increases after impoundment on phylum level. The influences of impoundment appear to be more apparent on order level that the relative abundances of four groups including Frankiales, Sphingomonadales, Sphingobacteriales and SubsectionI of class Cyanobacteria significantly vary after impoundment. In contrast, the predicted functional communities of bacterioplankton remain relatively stable that most of predicted functional categories including methane and nitrogen metabolisms have no significant variation after impoundment. Besides, significant distance decay patterns appear on the taxonomic communities after impoundment rather than the predicted functional communities. The environmental variables show significant impacts on the taxonomic community rather than predicted functional community, whereas the spatial variables have no effect on both taxonomic and predicted functional communities. In general, the taxonomic and predicted functional communities of bacterioplankton exhibit divergent responses to the impoundment in reservoir., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Faecal microorganisms represent a key threat to human health. Potential origins of faecal microbial contamination in a typical urban-representative micro-scale were evaluated. The quantitative polymerase chain reaction (qPCR) method was used in this study. The Bacteroidetes is selected as the indicative microorganism in runoff samples that are collected during four representative stormwater events in north China. The principal component analysis (PCA) method indicated the distribution feature of the environmental factors. The largest contributor is dog, followed by bird and human to the faecal pollution in stormwater runoff. The output of human and dog faecal pollutants in response to the first flush effect of nonpoint source pollution while the transmit time of bird faecal pollutant is relatively longer. In addition, the number of antecedent drying days represents the key factor for dog faecal pollution, while human faecal pollution is impacted by more factors. The results of this study will provide sound evidence for the tracking and management of nonpoint source faecal pollution in urban catchment areas.

A novel, Gram-stain-negative, motile, flagellated, aerobic, rod-shaped (0.5-0.7 µm wide and 1.0-1.2 µm long) and faint-yellow strain, designated ALS 84 T , was isolated from marine sediment sampled at Ailian bay, Rongcheng, PR China. Growth occurred in the presence of 1-3 % (w/v) NaCl (optimum, 2 % NaCl), at pH 4.0-8.0 (pH 6.0-7.0) and at 8-30 °C (28 °C). The genome size was 4.37 Mbp. The G+C content of the genomic DNA was 33.6 mol%. The results of phylogenetic analysis based on 16S rRNA gene sequences suggested that strain ALS 84 T belongs to the genus Flavicella within the family Flavobacteriaceae , and is most closely related to Flavicella marina (95.6 % similarity). The major fatty acids (>10 %) were iso-C 15 : 0 3-OH (22.9 %), iso-C 15 : 0 (14.0 %) and C 16 : 0 (10.9 %). The major polar lipids were phosphatidylethanolamine and three unidentified lipids. Menaquinone-6 (MK-6) was identified as the respiratory quinone. On the basis of the phenotypic, phylogenetic and chemotaxonomic data obtained in the study, strain ALS 84 T is considered to represent a novel species of the genus Flavicella , for which the name Flavicella sediminum sp. nov. is proposed. The type strain of the novel species is strain ALS 84 T (=KCTC 62398 T =MCCC 1K03480 T ).

A Gram-stain-negative, strictly aerobic, gliding-motile, rod-shaped and orange-pigmented bacterium, designated 1494 T , was isolated from marine sediment collected off the coast of Weihai, PR China. Strain 1494 T was found to grow at 4-37 °C (optimum, 30 °C), at pH 6.0-9.0 (pH 7.0) and in the presence of 0-8 % (w/v) NaCl (2 %). Cells were positive for oxidase and catalase activity. The results of 16S rRNA gene based phylogenetic analysis revealed that strain 1494 T belonged to the genus Formosa and exhibited the highest sequence similarity to Formosa spongicola KCTC 22662 T (98.4 %). Menaquinone-6 (MK-6) was detected as the major respiratory quinone. The dominant cellular fatty acids were iso-C 15 : 1 G and iso-C 15 : 0 . The DNA G+C content of strain 1494 T was 31.1 mol%. The major polar lipids included phosphatidylethanolamine, one unidentified phospholipid and one unidentified lipid. Based on its phylogenetic and phenotypic characteristics, strain 1494 T is considered to represent a novel species from the genus Formosa , for which the name Formosa maritima sp. nov. is proposed. The type strain is 1494 T (=KCTC 72531 T =MCCC 1H00385 T ).

A Gram-stain-negative, facultatively anaerobic, non-motile, rod-shaped and orange-pigmented bacterium, designated 1505 T , was isolated from marine sediment that was obtained off the coast of Weihai, PR China. Strain 1505 T was found to grow at 10-35 °C (optimum, 28 °C), at pH 6.0-9.0 (optimum, 7.5) and in the presence of 1-4 % (w/v) NaCl (optimum, 2 %). Cells were positive for oxidase and catalase activity. The 16S rRNA gene based phylogenetic analysis revealed that the nearest phylogenetic neighbours of strain 1505 T were Seonamhaeicola algicola Gy8 T (97.1 %), Seonamhaeicola marinus B011 T (96.3 %) and Seonamhaeicola aphaedonensis KCTC 32578 T (95.6 %). Based on phylogenomic analysis, the average nucleotide identity values between strain 1505 T and S. algicola Gy8 T , S. marinus B011 T and S. aphaedonensis KCTC 32578 T were 75.9, 76.0 and 77.7 %, respectively; the digital DNA-DNA hybridization values based on the draft genomes between strain 1505 T and S. algicola Gy8 T , S. marinus B011 T and S. aphaedonensis KCTC 32578 T were 20.0, 20.7 and 21.4 %, respectively. Menaquinone-6 (MK-6) was detected as the major respiratory quinone. The dominant cellular fatty acids were iso-C 15 : 1 G and C 18 : 1 ω9 c . The DNA G+C content of strain 1505 T was 33.3 mol%. The polar lipids included phosphatidylethanolamine, six aminolipids and four unidentified lipids. Based on its phylogenetic and phenotypic characteristics, strain 1505 T is considered to represent a novel species of the genus Seonamhaeicola , for which the name Seonamhaeicola maritimus sp. nov. is proposed. The type strain is 1505 T (=KCTC 72528 T =MCCC 1H00389 T ).

A yellow-pigmented bacterial strain, designated T13 T , was isolated from the rhizosphere soil of Alhagi sparsifolia collected from Xinjiang, PR China. Cells were rod-shaped, Gram-stain-negative, aerobic and gliding. Strain T13 T grew optimally at 25-30 °C and pH 7.0-8.0 with a NaCl tolerance of 0-2 % on Reasoner's 2A agar. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain T13 T belonged to the genus Flavobacterium within the family Flavobacteriaceae and was closely related to Flavobacterium nitrogenifigens KCTC 42884 T with a similarity value of 97.4 %. The major polar lipid was phosphatidylethanolamine; the only respiratory quinone was MK-6, and the polyamine profile contained sym -homospermidine as the major polyamine and a trace amount of spermidine. The major fatty acids were iso-C 15 : 0 , C16 :  1 ω7 c and summed feature 3 (comprising C 16 : 1 ω7 c or C 16 : 1 ω6 c ). The G+C content of the genomic DNA was 34.1 mol%. It is concluded from the phenotypic and genotypic data that strain T13 T represents a novel species of the genus Flavobacterium , for which the name Flavobacteriumustbae sp. nov. with the type strain T13 T (=KCTC 62874 T =ACCC 60126 T ) is proposed.