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Yang J, Yao M, Zhang D, Zhao Y, Gao G. Microbial community diversity analysis of kiwifruit pollen and identification of potential pathogens. Antonie Van Leeuwenhoek 2024; 117:114. [PMID: 39164415 DOI: 10.1007/s10482-024-02013-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2024] [Accepted: 08/16/2024] [Indexed: 08/22/2024]
Abstract
The kiwifruit industry typically uses commercial pollen for artificial pollination. However, during the collection of male flowers and pollen production, pollen can be easily contaminated by pathogenic bacteria that cause diseases such as canker and flower rot. Consequently, it is crucial to understand the structure of the pollen microbial community. This study employed Illumina high-throughput sequencing technology to analyze the fungal and bacterial composition in pollen samples from various regions in Shaanxi Province. Concurrently, potential pathogenic strains were isolated using traditional microbial isolation and cultivation techniques, and their molecular identification was performed through 16S rDNA sequence analysis. A tieback test was conducted on healthy branches to verify the pathogenicity of the strains. The results revealed a rich diversity of fungi and bacteria in kiwifruit pollen. At the phylum level, pollen fungi were mainly distributed in Ascomycota, and bacteria were mainly distributed in Proteobacteria and Firmicutes. The dominant fungal genera were Mycosphaerella, Aspergillus, and Cladosporium; the dominant bacterial genera were Weissella, Pantoea, Enterobacter, and Pseudomonas, respectively. Additionally, both Erwinia persicina and Pseudomonas fluorescens, isolated from pollen, exhibited high pathogenicity toward healthy kiwifruit branches. These findings contribute to a deeper understanding of the microbial diversity in commercial kiwifruit pollen used for mass pollination.
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Affiliation(s)
- Jiaqi Yang
- College of Food Engineering and Nutritional Science, Shaanxi Normal University, Xi'an, 710119, Shaanxi, China
| | - Manli Yao
- College of Food Engineering and Nutritional Science, Shaanxi Normal University, Xi'an, 710119, Shaanxi, China
| | - Dan Zhang
- College of Food Engineering and Nutritional Science, Shaanxi Normal University, Xi'an, 710119, Shaanxi, China
| | - Yu Zhao
- College of Food Engineering and Nutritional Science, Shaanxi Normal University, Xi'an, 710119, Shaanxi, China
| | - Guitian Gao
- College of Food Engineering and Nutritional Science, Shaanxi Normal University, Xi'an, 710119, Shaanxi, China.
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Wu D, Zou Y, Xiao J, Mo L, Lek S, Chen B, Fu Q, Guo Z. The spatiotemporal variations of microbial community in relation to water quality in a tropical drinking water reservoir, Southmost China. Front Microbiol 2024; 15:1354784. [PMID: 38770023 PMCID: PMC11102952 DOI: 10.3389/fmicb.2024.1354784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Accepted: 04/08/2024] [Indexed: 05/22/2024] Open
Abstract
It is well-known that water quality has great significance on microbial community composition in aquatic environments. In this study, we detected water column indicates the microbial community composition of nine sampling sites over two seasons using Illumina TruSeq sequencing in Songtao Reservoir, Hainan Province, Southmost China. The study indicated that the dominant phylum was Actinobacteria, Proteobacteria, Bacteroidetes, and Cyanobacteria. The diversity parameters showed that the microbial community composition had significant spatiotemporal variations, including the significantly higher Shannon index and Simpson index upstream than those midstream and downstream. Besides, there were significantly higher Chao1 index, Shannon index, and Simpson index in winter than in summer. Principal coordinates analysis (PCoA) showed the microbial structural composition had significant seasonal differences. The results of microbial community composition further revealed that the eutrophication level upstream was higher than that of midstream and downstream. The redundancy analysis (RDA) diagram indicated that the abundance of microbiology species significantly correlated with temperature, total phosphorus, Se, and Ni. Furthermore, the mantel's test showed that the temperature and total phosphorus significantly affected the community composition of archaea and bacteria. Overall, our finding here partially validated our hypothesis that the spatiotemporal variations of microbial community composition are significantly related to nutrients, physicochemical factors and metals, which has been unknown previously in tropical drinking waterbodies. This study substantially contributed to understanding of the composition of microbial community in tropical drinking water reservoirs and the main environmental driving factors in tropical zones. It also provided a reference for the management of reservoir operation to ensure drinking water safe.
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Affiliation(s)
- Di Wu
- School of Life and Health Sciences, Key Laboratory of Tropical Biological Resources of Ministry of Education, State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, China
| | - Ying Zou
- School of Life and Health Sciences, Key Laboratory of Tropical Biological Resources of Ministry of Education, State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, China
| | - Juan Xiao
- School of Life and Health Sciences, Key Laboratory of Tropical Biological Resources of Ministry of Education, State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, China
| | - Ling Mo
- Institute of Environmental Sciences, Haikou, Hainan Province, China
| | - Sovan Lek
- School of Life and Health Sciences, Key Laboratory of Tropical Biological Resources of Ministry of Education, State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, China
- Laboratoire Evolution & Diversité Biologique, Université Paul Sabatier, Toulouse, France
| | - Bo Chen
- National Health Commission of the People's Republic of China Key Laboratory of Control of Tropical Diseases Control, School of Tropical Medicine, Hainan Medical University, Haikou, Hainan, China
| | - Qiongyao Fu
- National Health Commission of the People's Republic of China Key Laboratory of Control of Tropical Diseases Control, School of Tropical Medicine, Hainan Medical University, Haikou, Hainan, China
| | - Zhiqiang Guo
- School of Life and Health Sciences, Key Laboratory of Tropical Biological Resources of Ministry of Education, State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, China
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Wu S, Lu J, Li C, Du H, Xu Y. Pediococcus spp. -mediated competition interaction within Daqu microbiota determines the temperature formation and metabolic profiles. Appl Environ Microbiol 2024; 90:e0179023. [PMID: 38506521 PMCID: PMC11022566 DOI: 10.1128/aem.01790-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Accepted: 01/08/2024] [Indexed: 03/21/2024] Open
Abstract
Fermented microbiota is critical to the formation of microenvironment and metabolic profiles in spontaneous fermentation. Microorganisms generate a diverse array of metabolites concurrent with the release of heat energy. In the case of Daqu fermentation, the peak temperature exceeded 60°C, forming a typical high-temperature fermentation system known as high-temperature Daqu. However, microorganisms that cause the quality variation in Daqu and how they affect the functional microbiota and microenvironment in the fermentation process are not yet clear. This study adopted high-throughput sequencing and monitored the dynamic fluctuations of metabolites and environmental factors to identify the pivotal microorganism responsible for the alterations in interaction patterns of functional keystone taxa and quality decline in the fermentation system of different operational areas during the in situ fermentation process that had been mainly attributed to operational taxonomic unit (OTU)_22 (Pediococcus acidilactici). Additionally, we used isothermal microcalorimetry, plate inhibition experiments, and in vitro simulation fermentation experiments to explore the impact of Pediococcus spp. on heat generation, microorganisms, and metabolite profiles. Results showed the heat peak generated by Pediococcus spp. was significantly lower than that of Bacillus spp., filamentous fungi, and yeast. In addition, the preferential growth of P. acidilactici strain AA3 would obviously affect other strains to colonize through competition, and its metabolites made a significant impact on filamentous fungi. The addition of P. acidilactici strain AA3 in simulated fermentation would cause the loss of pyrazines and acids in metabolites. These evidences showed that the overgrowth of Pediococcus spp. greatly influenced the formation of high temperatures and compounds in solid-state fermentation systems. Our work illustrated the vital impact of interaction variability mediated by Pediococcus spp. for microbial assembly and metabolites, as well as in forming temperature. These results emphasized the functional role of Daqu microbiota in metabolites and heat production and the importance of cooperation in improving the fermentation quality.IMPORTANCEThe stable and high-quality saccharifying and fermenting starter in traditional solid-state fermentation was the prerequisite for liquor brewing. An imbalance of microbial homeostasis in fermentation can adversely impact production quality. Identification of such critical microorganisms and verifying their associations with other fermentation parameters pose a challenge in a traditional fermentation environment. To enhance the quality of spontaneous fermented products, strategies such as bioaugmentation or the control of harmful microorganisms would be employed. This work started with the differences in high-temperature Daqu metabolites to explore a series of functional microorganisms that could potentially contribute to product disparities, and found that the differences in interactions facilitated directly or indirectly by Pediococcus spp. seriously affected the development of microbial communities and metabolites, as well as the formation of the microenvironment. This study not only identified functional microbiota in Daqu that affected fermentation quality, but also demonstrated how microorganisms interact to affect the fermentation system, which would provide guidance for microbial supervision in the actual production process. Besides, the application of isothermal microcalorimetry in this study was helpful for us to understand the heat production capacity of microorganisms and their adaptability to the environment. This study presented a commendable framework for improving and controlling the quality of traditional fermentation and inspired further investigations in similar systems.
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Affiliation(s)
- Shenglu Wu
- Lab of Brewing Microbiology and Applied Enzymology, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
- Key Laboratory of Industrial Biotechnology of Ministry of Education, Jiangnan University, Wuxi, Jiangsu, China
| | - Jun Lu
- Guizhou Guotai Liquor Group Co. Ltd., Zunyi, Guizhou, China
| | - Changwen Li
- Guizhou Guotai Liquor Group Co. Ltd., Zunyi, Guizhou, China
| | - Hai Du
- Lab of Brewing Microbiology and Applied Enzymology, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
- Key Laboratory of Industrial Biotechnology of Ministry of Education, Jiangnan University, Wuxi, Jiangsu, China
| | - Yan Xu
- Lab of Brewing Microbiology and Applied Enzymology, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
- Key Laboratory of Industrial Biotechnology of Ministry of Education, Jiangnan University, Wuxi, Jiangsu, China
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Finn DR. A metagenomic alpha-diversity index for microbial functional biodiversity. FEMS Microbiol Ecol 2024; 100:fiae019. [PMID: 38337180 PMCID: PMC10939414 DOI: 10.1093/femsec/fiae019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 12/15/2023] [Accepted: 02/08/2024] [Indexed: 02/12/2024] Open
Abstract
Alpha-diversity indices are an essential tool for describing and comparing biodiversity. Microbial ecologists apply indices originally intended for, or adopted by, macroecology to address questions relating to taxonomy (conserved marker) and function (metagenome-based data). In this Perspective piece, I begin by discussing the nature and mathematical quirks important for interpreting routinely employed alpha-diversity indices. Secondly, I propose a metagenomic alpha-diversity index (MD) that measures the (dis)similarity of protein-encoding genes within a community. MD has defined limits, whereby a community comprised mostly of similar, poorly diverse protein-encoding genes pulls the index to the lower limit, while a community rich in divergent homologs and unique genes drives it toward the upper limit. With data acquired from an in silico and three in situ metagenome studies, I derive MD and typical alpha-diversity indices applied to taxonomic (ribosomal rRNA) and functional (all protein-encoding) genes, and discuss their relationships with each other. Not all alpha-diversity indices detect biological trends, and taxonomic does not necessarily follow functional biodiversity. Throughout, I explain that protein Richness and MD provide complementary and easily interpreted information, while probability-based indices do not. Finally, considerations regarding the unique nature of microbial metagenomic data and its relevance for describing functional biodiversity are discussed.
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Affiliation(s)
- Damien R Finn
- Thünen Institut für Biodiversität, Johann Heinrich von Thünen Institut, Braunschweig 38116, Germany
- Institut für Geoökologie, Technische Universität Braunschweig, Braunschweig 38106, Germany
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Danov A, Segev O, Bograd A, Ben Eliyahu Y, Dotan N, Kaplan T, Levy A. Toxinome-the bacterial protein toxin database. mBio 2024; 15:e0191123. [PMID: 38117054 PMCID: PMC10790787 DOI: 10.1128/mbio.01911-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 11/14/2023] [Indexed: 12/21/2023] Open
Abstract
IMPORTANCE Microbes use protein toxins as important tools to attack neighboring cells, microbial or eukaryotic, and for self-killing when attacked by viruses. These toxins work through different mechanisms to inhibit cell growth or kill cells. Microbes also use antitoxin proteins to neutralize the toxin activities. Here, we developed a comprehensive database called Toxinome of nearly two million toxins and antitoxins that are encoded in 59,475 bacterial genomes. We described the distribution of bacterial toxins and identified that they are depleted by bacteria that live in hot and cold temperatures. We found 5,161 cases in which toxins and antitoxins are densely clustered in bacterial genomes and termed these areas "Toxin Islands." The Toxinome database is a useful resource for anyone interested in toxin biology and evolution, and it can guide the discovery of new toxins.
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Affiliation(s)
- Aleks Danov
- Department of Plant Pathology and Microbiology, Institute of Environmental Science, The Faculty of Agriculture, Food, and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Ofir Segev
- Department of Plant Pathology and Microbiology, Institute of Environmental Science, The Faculty of Agriculture, Food, and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Avi Bograd
- Department of Plant Pathology and Microbiology, Institute of Environmental Science, The Faculty of Agriculture, Food, and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Yedidya Ben Eliyahu
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Noam Dotan
- Department of Brain Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Tommy Kaplan
- School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem, Israel
- Department of Developmental Biology and Cancer Research, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Asaf Levy
- Department of Plant Pathology and Microbiology, Institute of Environmental Science, The Faculty of Agriculture, Food, and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
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Kumar S, Najar IN, Sharma P, Tamang S, Mondal K, Das S, Sherpa MT, Thakur N. Temperature - A critical abiotic paradigm that governs bacterial heterogeneity in natural ecological system. ENVIRONMENTAL RESEARCH 2023; 234:116547. [PMID: 37422118 DOI: 10.1016/j.envres.2023.116547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 06/28/2023] [Accepted: 07/01/2023] [Indexed: 07/10/2023]
Abstract
A baseline data has been presented here to prove that among the abiotic factors, temperature is the most critical factor that regulates and governs the bacterial diversity in a natural ecosystem. Present study in Yumesamdong hot springs riverine vicinity (Sikkim), parades a gamut of bacterial communities in it and hosts them from semi-frigid region (- 4-10 °C) to fervid region (50-60 °C) via an intermediate region (25-37 °C) within the same ecosystem. This is an extremely rare intriguing natural ecosystem that has no anthropogenic disturbances nor any artificial regulation of temperature. We scanned the bacterial flora through both the culture-dependent and culture-independent techniques in this naturally complex thermally graded habitat. High-throughput sequencing gave bacterial and archaeal phyla representatives of over 2000 species showcasing their biodiversity. Proteobacteria, Firmicutes, Bacteroidetes and Chloroflexi were the predominant phyla. A concave down-curve significance was found in temperature-abundance correlation as the number of microbial taxa decreased when the temperature increased from warm (35 °C) to hot (60 °C). Firmicutes showed significant linear increase from cold to hot environment whereas Proteobacteria followed the opposite trend. No significant correlation was observed for physicochemical parameters against the bacterial diversity. However, only temperature has shown significant positive correlation to the predominant phyla at their respective thermal gradients. The antibiotic resistance patterns correlated with temperature gradient where the prevalence of antibiotic resistance was higher in case of mesophiles than that of psychrophiles and there was no resistance in thermophiles. The antibiotic resistant genes obtained were solely from mesophiles as it conferred high resistance at mesophilic conditions enabling them to adapt and metabolically compete for survival. Our study concludes that the temperature is a major factor that plays a significant contribution in shaping the bacterial community structure in any thermal gradient edifice.
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Affiliation(s)
- Santosh Kumar
- Department of Microbiology, School of Life Sciences, Sikkim University, Gangtok, 737102, Sikkim, India
| | - Ishfaq Nabi Najar
- Department of Microbiology, School of Life Sciences, Sikkim University, Gangtok, 737102, Sikkim, India
| | - Prayatna Sharma
- Department of Microbiology, School of Life Sciences, Sikkim University, Gangtok, 737102, Sikkim, India
| | - Sonia Tamang
- Department of Microbiology, School of Life Sciences, Sikkim University, Gangtok, 737102, Sikkim, India
| | - Krishnendu Mondal
- Department of Microbiology, Vidyasagar University, Midnapore, 721102, India
| | - Sayak Das
- Department of Life Science & Bioinformatics, HK School of Life Sciences, Assam University, Silchar, 788011, Assam, India
| | - Mingma Thundu Sherpa
- Department of Microbiology, School of Life Sciences, Sikkim University, Gangtok, 737102, Sikkim, India
| | - Nagendra Thakur
- Department of Microbiology, School of Life Sciences, Sikkim University, Gangtok, 737102, Sikkim, India.
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Ohore OE, Ifon BE, Wang Y, Kazmi SSUH, Zhang J, Sanganyado E, Jiao X, Liu W, Wang Z. Vertical changes in water depth and environmental variables drove the antibiotics and antibiotic resistomes distribution, and microbial food web structures in the estuary and marine ecosystems. ENVIRONMENT INTERNATIONAL 2023; 178:108118. [PMID: 37517178 DOI: 10.1016/j.envint.2023.108118] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 06/29/2023] [Accepted: 07/25/2023] [Indexed: 08/01/2023]
Abstract
The influence of vertical changes in water depth on emerging pollutants distribution and microbial food web remains elusive. We investigated the influence of vertical transition in water depth on the environmental variables, antibiotics and antibiotic resistomes, and microbial community structures in estuary and marine ecosystems (0-50 m). Stepwise multiple linear regression model showed that among investigated environmental variables, change in water salinity was the most influential factor dictating the fluoroquinolone and macrolides concentrations, while dissolved oxygen and turbidity were the key influencers of sulfonamides and beta-lactam concentrations, respectively. Bacterial and eukaryotic diversity and niche breadth significantly increased with the increasing water depth. Ecosystem food web structure at the bottom depths was more stable than at the middle and surface depths. At the surface depth, the top 5 keystone genera were Cryothecomonas, Syndiniales, Achromobacter, Pseudopirsonia, and Karlodinium. Whereas Eugregarinorida, Neptuniibacter, Mychonastes, Novel_Apicomplexa_Class_1, Aplanochytrium and Dietzia, Halodaphnea, Luminiphilus, Aplanochytrium, Maullinia dominated the top 5 genera at the middle and the bottom depth, respectively. Absolute abundance of antibiotic resistance genes (ARGs) was drastically increased at the surface depth compared with the middle and bottom depths. Abundance of the top 10 ARGs and mobile genetic elements (MGEs) detected including tnpA-05, aadA2-03, mexF, aadA1, intI-1(clinic), qacEdelta1-02, aadA-02, qacEdelta1-01, cmlA1-01, and aadA-01 were amplified at the surface depth. This study demonstrated that ARGs abundance was disproportionate to bacterial diversity, and anthropogenic disturbances, confinement, MGEs, and ecosystem stability play primary roles in the fate of ARGs. The findings of this study also implicate that vertical changes in the water depth on environmental conditions can influence antibiotic concentrations and microbial community dramatically.
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Affiliation(s)
- Okugbe Ebiotubo Ohore
- Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, and Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou 515063, China
| | - Binessi Edouard Ifon
- CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; Laboratory of Physical Chemistry, University of Abomey-Calavi, Republic of Benin, Cotonou 01 BP 4521, Benin
| | - Yuwen Wang
- Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, and Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou 515063, China
| | - Syed Shabi Ul Hassan Kazmi
- Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, and Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou 515063, China
| | - Jingli Zhang
- Department of Clinical Medicine, Shantou University Medical College, Shantou, Guangdong 515041, China
| | - Edmond Sanganyado
- Department of Applied Sciences, Northumbria University, Newcastle Upon Tyne NE2 4PB, UK
| | - Xiaoyang Jiao
- Department of Cell Biology and Genetics, Shantou University Medical College, Shantou, Guangdong 515041, China
| | - Wenhua Liu
- Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, and Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou 515063, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
| | - Zhen Wang
- Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, and Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou 515063, China.
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Wang X, Yin Y, Yu Z, Shen G, Cheng H, Tao S. Distinct distribution patterns of the abundant and rare bacteria in high plateau hot spring sediments. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 863:160832. [PMID: 36521602 DOI: 10.1016/j.scitotenv.2022.160832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Revised: 12/02/2022] [Accepted: 12/06/2022] [Indexed: 06/17/2023]
Abstract
The diversity and distribution patterns of the abundant and rare microbial sub-communities in hot spring ecosystems and their assembly mechanisms are poorly understood. The present study investigated the diversity and distribution patterns of the total, abundant, conditionally rare, and always rare taxa in the low- and moderate-temperature hot spring sediments on the Tibetan Plateau based on high-throughput 16S rRNA gene sequencing, and explored their major environmental drivers. The diversity of these four bacterial taxa showed no significant change between the low-temperature and moderate-temperature hot spring sediments, whereas the bacterial compositions were obviously different. Stochasticity dominated the bacterial sub-community assemblages, while heterogeneous selection also played an important role in shaping the abundant and conditionally rare taxa between the low-temperature and moderate-temperature hot spring sediments. No significant difference in the topological properties of co-occurrence networks was found between the conditionally rare and abundant taxa, and the connections between the paired operational taxonomic units (OTUs) were almost positive. The diversity of the total, abundant, and conditionally rare taxa was governed by the salinity of hot spring sediments, while that of the always rare taxa was determined by the content of S element. In contrast, temperature had significant direct effect on the composition of the total, abundant, and conditionally rare taxa, but relatively weak influence on that of the always rare taxa. Besides, salinity was another major environmental factor driving the composition of the abundant and rare sub-communities in the hot spring sediments. These results reveal the assembly processes and major environmental drivers that shaped different bacterial sub-communities in the hot spring sediments on the Tibetan Plateau, and indicate the importance of conditionally rare taxa in constructing bacterial communities. These findings enhance the current understanding of the ecological mechanisms maintaining the ecosystem stability and services in extreme environment.
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Affiliation(s)
- Xiaojie Wang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China; MOE Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Yue Yin
- MOE Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Zhiqiang Yu
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Guofeng Shen
- MOE Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Hefa Cheng
- MOE Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China.
| | - Shu Tao
- MOE Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
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Liu Q, Yang J, Wang B, Liu W, Hua Z, Jiang H. Influence of salinity on the diversity and composition of carbohydrate metabolism, nitrogen and sulfur cycling genes in lake surface sediments. Front Microbiol 2022; 13:1019010. [PMID: 36519167 PMCID: PMC9742235 DOI: 10.3389/fmicb.2022.1019010] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Accepted: 11/08/2022] [Indexed: 08/23/2023] Open
Abstract
Exploring functional gene composition is essential for understanding the biogeochemical functions of lakes. However, little is known about the diversity and composition of biogeochemical cycling genes and their influencing factors in saline lakes. In this study, metagenomic analysis was employed to characterize the diversity and composition of microbial functions predicted from genes involved in carbohydrate metabolisms, nitrogen, and sulfur cycles in 17 surface sediments of Qinghai-Tibetan lakes with salinity ranging from 0.7 to 31.5 g L-1. The results showed that relative abundances of carbohydrate-active enzyme (CAZy), nitrogen, and sulfur cycling genes were 92.7-116.5, 15.1-18.7, 50.8-63.9 per 1,000 amino acid coding reads, respectively. The Shannon diversity indices of CAZy and sulfur cycling genes decreased with increasing salinity, whereas nitrogen cycling gene diversity showed an opposite trend. Relative abundances of many CAZy (i.e., carbohydrate-binding module and carbohydrate esterase), nitrogen (i.e., anammox and organic degradation and synthesis) and sulfur (i.e., dissimilatory sulfur reduction and oxidation, link between inorganic and organic sulfur transformation, sulfur disproportionation and reduction) cycling gene categories decreased with increasing salinity, whereas some CAZy (i.e., auxiliary activity), nitrogen (i.e., denitrification) and sulfur (i.e., assimilatory sulfate reduction and sulfur oxidation) gene categories showed an increasing trend. The compositions of CAZy, nitrogen, and sulfur cycling genes in the studied lake sediments were significantly (p < 0.05) affected by environmental factors such as salinity, total organic carbon, total nitrogen, and total phosphorus, with salinity having the greatest influence. Together, our results suggest that salinity may regulate the biogeochemical functions of carbohydrate metabolisms, nitrogen, and sulfur cycles in lakes through changing the diversity and composition of microbial functional genes. This finding has great implications for understanding the impact of environmental change on microbial functions in lacustrine ecosystems.
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Affiliation(s)
- Qing Liu
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China
| | - Jian Yang
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China
| | - Beichen Wang
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China
| | - Wen Liu
- National and Local Joint Engineering Research Center of Ecological Treatment Technology for Urban Water Pollution, Zhejiang Provincial Key Laboratory for Water Environment and Marine Biological Resources Protection, College of Life and Environmental Science, Wenzhou University, Wenzhou, China
| | - Zhengshuang Hua
- Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei, China
| | - Hongchen Jiang
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China
- Qinghai Provincial Key Laboratory of Geology and Environment of Salt Lakes, Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining, China
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