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Butler J, Morgan S, Jones L, Upton M, Besinis A. Evaluating the antibacterial efficacy of a silver nanocomposite surface coating against nosocomial pathogens as an antibiofilm strategy to prevent hospital infections. Nanotoxicology 2024:1-27. [PMID: 39051684 DOI: 10.1080/17435390.2024.2379809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Revised: 07/04/2024] [Accepted: 07/05/2024] [Indexed: 07/27/2024]
Abstract
Antimicrobial nanocoatings may be a means of preventing nosocomial infections, which account for significant morbidity and mortality. The role of hospital sink traps in these infections is also increasingly appreciated. We describe the preparation, material characterization and antibacterial activity of a pipe cement-based silver nanocoating applied to unplasticized polyvinyl chloride, a material widely used in wastewater plumbing. Three-dimensional surface topography imaging and scanning electron microscopy showed increased roughness in all surface finishes versus control, with grinding producing the roughest surfaces. Silver stability within nanocoatings was >99.89% in deionized water and bacteriological media seeded with bacteria. The nanocoating exhibited potent antibiofilm (99.82-100% inhibition) and antiplanktonic (99.59-99.99% killing) activity against three representative bacterial species and a microbial community recovered from hospital sink traps. Hospital sink trap microbiota were characterized by sequencing the 16S rRNA gene, revealing the presence of opportunistic pathogens from genera including Pseudomonas, Enterobacter and Clostridioides. In a benchtop model sink trap system, nanocoating antibiofilm activity against this community remained significant after 11 days but waned following 25 days. Silver nanocoated disks in real-world sink traps in two university buildings had a limited antibiofilm effect, even though in vitro experiments using microbial communities recovered from the same traps demonstrated that the nanocoating was effective, reducing biofilm formation by >99.6% and killing >98% of planktonic bacteria. We propose that conditioning films forming in the complex conditions of real-world sink traps negatively impact nanocoating performance, which may have wider relevance to development of antimicrobial nanocoatings that are not tested in the real-world.
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Affiliation(s)
- James Butler
- School of Engineering, Computing and Mathematics, Faculty of Science and Engineering, University of Plymouth, Plymouth, United Kingdom
| | - Sian Morgan
- School of Engineering, Computing and Mathematics, Faculty of Science and Engineering, University of Plymouth, Plymouth, United Kingdom
| | - Lewis Jones
- Clinical Microbiology, University Hospitals Plymouth NHS Trust, Plymouth, United Kingdom
| | - Mathew Upton
- School of Biomedical Sciences, Faculty of Health, University of Plymouth, Plymouth, United Kingdom
| | - Alexandros Besinis
- School of Engineering, Computing and Mathematics, Faculty of Science and Engineering, University of Plymouth, Plymouth, United Kingdom
- Peninsula Dental School, Faculty of Health, University of Plymouth, Plymouth, United Kingdom
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2
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Zavarzina DG, Merkel AY, Klyukina AA, Elizarov IM, Pikhtereva VA, Rusakov VS, Chistyakova NI, Ziganshin RH, Maslov AA, Gavrilov SN. Iron or sulfur respiration-an adaptive choice determining the fitness of a natronophilic bacterium Dethiobacter alkaliphilus in geochemically contrasting environments. Front Microbiol 2023; 14:1108245. [PMID: 37520367 PMCID: PMC10376724 DOI: 10.3389/fmicb.2023.1108245] [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: 11/25/2022] [Accepted: 06/26/2023] [Indexed: 08/01/2023] Open
Abstract
Haloalkaliphilic microorganisms are double extremophiles functioning optimally at high salinity and pH. Their typical habitats are soda lakes, geologically ancient yet widespread ecosystems supposed to harbor relict microbial communities. We compared metabolic features and their determinants in two strains of the natronophilic species Dethiobacter alkaliphilus, the only cultured representative of the class "Dethiobacteria" (Bacillota). The strains of D. alkaliphilus were previously isolated from geographically remote Mongolian and Kenyan soda lakes. The type strain AHT1T was described as a facultative chemolithoautotrophic sulfidogen reducing or disproportionating sulfur or thiosulfate, while strain Z-1002 was isolated as a chemolithoautotrophic iron reducer. Here, we uncovered the iron reducing ability of strain AHT1T and the ability of strain Z-1002 for thiosulfate reduction and anaerobic Fe(II) oxidation. Key catabolic processes sustaining the growth of both D. alkaliphilus strains appeared to fit the geochemical settings of two contrasting natural alkaline environments, sulfur-enriched soda lakes and iron-enriched serpentinites. This hypothesis was supported by a meta-analysis of Dethiobacterial genomes and by the enrichment of a novel phylotype from a subsurface alkaline aquifer under Fe(III)-reducing conditions. Genome analysis revealed multiheme c-type cytochromes to be the most probable determinants of iron and sulfur redox transformations in D. alkaliphilus. Phylogeny reconstruction showed that all the respiratory processes in this organism are likely provided by evolutionarily related early forms of unconventional octaheme tetrathionate and sulfite reductases and their structural analogs, OmhA/OcwA Fe(III)-reductases. Several phylogenetically related determinants of anaerobic Fe(II) oxidation were identified in the Z-1002 genome, and the oxidation process was experimentally demonstrated. Proteomic profiling revealed two distinct sets of multiheme cytochromes upregulated in iron(III)- or thiosulfate-respiring cells and the cytochromes peculiar for Fe(II) oxidizing cells. We suggest that maintaining high variation in multiheme cytochromes is an effective adaptive strategy to occupy geochemically contrasting alkaline environments. We propose that sulfur-enriched soda lakes could be secondary habitats for D. alkaliphilus compared to Fe-rich serpentinites, and that the ongoing evolution of Dethiobacterales could retrace the evolutionary path that may have occurred in prokaryotes at a turning point in the biosphere's history, when the intensification of the sulfur cycle outweighed the global significance of the iron cycle.
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Affiliation(s)
- Daria G. Zavarzina
- Winogradsky Institute of Microbiology, FRC Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Alexander Yu Merkel
- Winogradsky Institute of Microbiology, FRC Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Alexandra A. Klyukina
- Winogradsky Institute of Microbiology, FRC Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Ivan M. Elizarov
- Winogradsky Institute of Microbiology, FRC Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Valeria A. Pikhtereva
- Winogradsky Institute of Microbiology, FRC Biotechnology, Russian Academy of Sciences, Moscow, Russia
- Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia
| | | | | | - Rustam H. Ziganshin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Alexey A. Maslov
- Faculty of Geology, Lomonosov Moscow State University, Moscow, Russia
| | - Sergey N. Gavrilov
- Winogradsky Institute of Microbiology, FRC Biotechnology, Russian Academy of Sciences, Moscow, Russia
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3
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Dick JM, Tan J. Chemical Links Between Redox Conditions and Estimated Community Proteomes from 16S rRNA and Reference Protein Sequences. MICROBIAL ECOLOGY 2023; 85:1338-1355. [PMID: 35503575 DOI: 10.1007/s00248-022-01988-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 02/28/2022] [Indexed: 05/10/2023]
Abstract
Environmental influences on community structure are often assessed through multivariate analyses in order to relate microbial abundances to separately measured physicochemical variables. However, genes and proteins are themselves chemical entities; in combination with genome databases, differences in microbial abundances directly encode for chemical variability. We predicted that the carbon oxidation state of estimated community proteomes, obtained by combining taxonomic abundances from published 16S rRNA gene sequencing datasets with reference microbial proteomes from the NCBI Reference Sequence (RefSeq) database, would reflect environmental oxidation-reduction conditions. Analysis of multiple datasets confirms the geobiochemical predictions for environmental redox gradients in hydrothermal systems, stratified lakes and marine environments, and shale gas wells. The geobiochemical signal is largest for the steep redox gradients associated with hydrothermal systems and between injected water and produced fluids from shale gas wells, demonstrating that microbial community composition can be a chemical proxy for environmental redox gradients. Although estimates of oxidation state from 16S amplicon and metagenomic sequences are correlated, the 16S-based estimates show stronger associations with redox gradients in some environments.
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Affiliation(s)
- Jeffrey M Dick
- Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring, Ministry of Education, School of Geosciences and Info-Physics, Central South University, Changsha, 410083, China.
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China.
| | - Jingqiang Tan
- Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring, Ministry of Education, School of Geosciences and Info-Physics, Central South University, Changsha, 410083, China
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4
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Yang Z, Wei Y, Wu W, Zhang L, Wang J, Shan A. Characterization of simplified nonapeptides with broad-spectrum antimicrobial activities as potential food preservatives, and their antibacterial mechanism. Food Funct 2023; 14:3139-3154. [PMID: 36892465 DOI: 10.1039/d2fo03861g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/10/2023]
Abstract
Antimicrobial peptides (AMPs) have attracted attention in the field of food preservatives due to their favorable biosafety and potential antimicrobial activity. However, high synthetic cost, systemic toxicity, a narrow antimicrobial spectrum, and poor antimicrobial activity become the main bottlenecks for their practical applications. To address these questions, a set of derived nonapeptides were designed based on a previously discovered ultra-short peptide sequence template (RXRXRXRXL-NH2) and screened to identify an optimal peptide-based food preservative with excellent antimicrobial properties. Among these nonapeptides, the designed peptides 3IW (RIRIRIRWL-NH2) and W2IW (RWRIRIRWL-NH2) presented a membrane-disruptive and reactive oxygen species (ROS) accumulation mechanism to execute potent and rapid broad-spectrum antimicrobial activity without observed cytotoxicity. Moreover, they exhibited favorable antimicrobial stability regardless of high ionic strength, heat, and excessive acid-base conditions, retaining potent antimicrobial effects for chicken meat preservation. Collectively, their ultra-short sequence length and potent broad-spectrum antimicrobial capacity may be beneficial for the further development of green and safe peptide-based food preservatives.
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Affiliation(s)
- Zhanyi Yang
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, 150030, China.
| | - Yingxin Wei
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, 150030, China.
| | - Wanpeng Wu
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, 150030, China.
| | - Licong Zhang
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, 150030, China.
| | - Jiajun Wang
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, 150030, China.
| | - Anshan Shan
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, 150030, China.
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Peera Sheikh Kulsum PG, Khanam R, Das S, Nayak AK, Tack FMG, Meers E, Vithanage M, Shahid M, Kumar A, Chakraborty S, Bhattacharya T, Biswas JK. A state-of-the-art review on cadmium uptake, toxicity, and tolerance in rice: From physiological response to remediation process. ENVIRONMENTAL RESEARCH 2023; 220:115098. [PMID: 36586716 DOI: 10.1016/j.envres.2022.115098] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 12/01/2022] [Accepted: 12/15/2022] [Indexed: 06/17/2023]
Abstract
Cadmium (Cd), a major contaminant of concern, has been extensively reviewed and debated for its anthropogenic global shifts. Cadmium levels in rice grains raise wide food safety concerns. The aim of this review is therefore to capture the dynamics of Cd in paddy soil, translocation pathways of Cd from soil to consumption rice, and assess its bio-accessibility in human consumption. In crop plants, Cd reduces absorption of nutrients and water, triggers oxidative stress, and inhibits plant metabolism. Understanding the mechanisms and behaviour of Cd in paddy soil and rice allows to explain, predict and intervene in Cd transferability from soil to grains and human exposure. Factors affecting Cd movement in soil, and further to rice grain, are elucidated. Recently, physiological and molecular understanding of Cd transport in rice plants have been advanced. Morphological-biochemical characteristics and Cd transporters of plants in such a movement were also highlighted. Ecologically viable remediation approaches, including low input cost agronomic methods, phytoremediation and microbial bioremediation methods, are emerging.
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Affiliation(s)
| | - Rubina Khanam
- ICAR-Crop Production Division, National Rice Research Institute, Cuttack, 753006, Odisha, India
| | - Shreya Das
- Department of Agricultural Chemistry and Soil Science, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, 741252, West Bengal, India
| | - Amaresh Kumar Nayak
- ICAR-Crop Production Division, National Rice Research Institute, Cuttack, 753006, Odisha, India
| | - Filip M G Tack
- Department of Green Chemistry and Technology, Ghent University, Ghent, Belgium
| | - Erik Meers
- Department of Green Chemistry and Technology, Ghent University, Ghent, Belgium
| | - Meththika Vithanage
- Ecosphere Resilience Research Centre, Faculty of Applied Sciences, University of Sri Jayewardenepura, Sri Lanka
| | - Mohammad Shahid
- ICAR-Crop Production Division, National Rice Research Institute, Cuttack, 753006, Odisha, India
| | - Anjani Kumar
- ICAR-Crop Production Division, National Rice Research Institute, Cuttack, 753006, Odisha, India
| | - Sukalyan Chakraborty
- Environmental Engineering Laboratory, Department of Civil & Environmental Engineering, Birla Institute of Technology, Mesra, Jharkhand, 835215, India
| | - Tanushree Bhattacharya
- Environmental Engineering Laboratory, Department of Civil & Environmental Engineering, Birla Institute of Technology, Mesra, Jharkhand, 835215, India
| | - Jayanta Kumar Biswas
- Department of Ecological Studies &International Centre for Ecological Engineering, Universityof Kalyani, Kalyani, Nadia, 741235, West Bengal, India.
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6
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Anand S, Singh A, Kumar V. Recent advancements in cadmium-microbe interactive relations and their application for environmental remediation: a mechanistic overview. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:17009-17038. [PMID: 36622611 DOI: 10.1007/s11356-022-25065-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Accepted: 12/26/2022] [Indexed: 01/10/2023]
Abstract
The toxic and persistent nature of cadmium (Cd) in the environment has become a matter of concern with its drastic increase in the concentrations over past few decades. Among the various techniques, the microbial remediation has been accepted as an effective decontamination tool for environmental applications, which is sustainable over a period of time. The Cd decontamination potential of the microbes depends on various internal and external factors that play a crucial role in selection of the microbes for application in a particular environment. Thus, it is important to understand the role of these factors for optimal application of the microbes. This study provides an insight into the mechanisms involved between the microbes and the environmental Cd. The study also briefly reviews the mathematical models that have been used to predict the remediation potential of the microbes and the kinetics involved during the process. A critical analysis of the recent advancements in the techniques for use of bacteria, fungi, and algal cells to remove Cd has been also presented in the manuscript.
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Affiliation(s)
- Saumya Anand
- Laboratory of Applied Microbiology, Department of Environmental Science and Engineering, Indian Institute of Technology (Indian School of Mines), Dhanbad, Jharkhand, India, 826004
| | - Ankur Singh
- Laboratory of Applied Microbiology, Department of Environmental Science and Engineering, Indian Institute of Technology (Indian School of Mines), Dhanbad, Jharkhand, India, 826004
| | - Vipin Kumar
- Laboratory of Applied Microbiology, Department of Environmental Science and Engineering, Indian Institute of Technology (Indian School of Mines), Dhanbad, Jharkhand, India, 826004.
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7
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Xia M, Zhang X, Xiao Y, Sheng Q, Tu L, Chen F, Yan Y, Zheng Y, Wang M. Interaction of acetic acid bacteria and lactic acid bacteria in multispecies solid-state fermentation of traditional Chinese cereal vinegar. Front Microbiol 2022; 13:964855. [PMID: 36246224 PMCID: PMC9557190 DOI: 10.3389/fmicb.2022.964855] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 09/12/2022] [Indexed: 11/13/2022] Open
Abstract
The microbial community plays an important role on the solid-state fermentation (SSF) of Chinese cereal vinegar, where acetic acid bacteria (AAB) and lactic acid bacteria (LAB) are the dominant bacteria. In this study, the top-down (in situ) and bottom-up (in vitro) approaches were employed to reveal the interaction of AAB and LAB in SSF of Shanxi aged vinegar (SAV). The results of high-throughput sequencing indicates that Acetobacter pasteurianus and Lactobacillus helveticus are the predominant species of AAB and LAB, respectively, and they showed negative interrelationship during the fermentation. A. pasteurianus CGMCC 3089 and L. helveticus CGMCC 12062, both of which were isolated from fermentation of SAV, showed no nutritional competition when they were co-cultured in vitro. However, the growth and metabolism of L. helveticus CGMCC 12062 were inhibited during SSF due to the presence of A. pasteurianus CGMCC 3089, indicating an amensalism phenomenon between these two species. The transcriptomic results shows that there are 831 differentially expressed genes (|log2 (Fold Change)| > 1 and, p ≤ 0.05) in L. helveticus CGMCC 12062 under co-culture condition comparing to its mono-culture, which are mainly classified into Gene Ontology classification of molecular function, biological process, and cell composition. Of those 831 differentially expressed genes, 202 genes are up-regulated and 629 genes are down-regulated. The down-regulated genes were enriched in KEGG pathways of sugar, amino acid, purine, and pyrimidine metabolism. The transcriptomic results for A. pasteurianus CGMCC 3089 under co-culture condition reveals 529 differentially expressed genes with 393 up-regulated and 136 down-regulated, and the genes within KEGG pathways of sugar, amino acid, purine, and pyrimidine metabolism are up-regulated. Results indicate an amensalism relationship in co-culture of A. pasteurianus and L. helveticus. Therefore, this work gives a whole insight on the interaction between the predominant species in SSF of cereal vinegar from nutrient utilization, endogenous factors inhibition and the regulation of gene transcription.
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Affiliation(s)
- Menglei Xia
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Xiaofeng Zhang
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Yun Xiao
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Qing Sheng
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Linna Tu
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Fusheng Chen
- Hubei International Scientific and Technological Cooperation Base of Traditional Fermented Foods, Huazhong Agricultural University, Wuhan, China
| | - Yufeng Yan
- Shanxi Zilin Vinegar Industry Co., Ltd., Shanxi Province Key Laboratory of Vinegar Fermentation Science and Engineering, Taiyuan, China
| | - Yu Zheng
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China,*Correspondence: Yu Zheng, Min Wang,
| | - Min Wang
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China,*Correspondence: Yu Zheng, Min Wang,
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8
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Ma X, Johnson KB, Gu B, Zhang H, Li G, Huang X, Xia X. The in-situ release of algal bloom populations and the role of prokaryotic communities in their establishment and growth. WATER RESEARCH 2022; 219:118565. [PMID: 35597219 DOI: 10.1016/j.watres.2022.118565] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 05/03/2022] [Accepted: 05/05/2022] [Indexed: 06/15/2023]
Abstract
Harmful algal blooms (HABs) may quickly travel and inoculate new water bodies via currents and runoff in estuaries. The role of in-situ prokaryotic communities in the re-establishment and growth of inoculated algal blooms remains unknown. A novel on-board incubation experiment was employed to simulate the sudden surge of algal blooms to new estuarine waters and reveal possible outcomes. A dinoflagellate (Amphidinium carterae) and a diatom species (Thalassiosira weissflogii) which had bloomed in the Pearl River Estuary (PRE) area were cultured to bloom densities and reintroduced back into PRE natural seawaters. The diatom showed better adaptation ability to the new environment and increased significantly after the incubation. Simultaneously, particle-attached (PA) prokaryotic community structure was strongly influenced by adding of the diatom, with some opportunistic prokaryotes significantly enhanced in the diatom treatment. Whereas the dinoflagellate population did not increase following incubation, and their PA prokaryotic community showed no significant differences relative to the control. Metagenomic analyzes revealed that labile carbohydrates and organic nitrogen produced by the diatom contributed to the surge of certain PA prokaryotes. Genomic properties of a bacteria strain, which is affiliated with genus GMD16E07 (Planctomycetaceae) and comprised up to 50% of PA prokaryotes in the diatom treatment, was described here for the first time. Notably, the association of Planctomycetaceae and T. weissflogii likely represents symbiotic mutualism, with the diatom providing organic matter for Planctomycetaceae and the bacteria supplying vitamins and detoxifying nitriles and hydrogen peroxides in exchange. Therefore, the close association between Planctomycetaceae and T. weissflogii promoted the growth of both populations, and eventually facilitated the diatom bloom establishment.
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Affiliation(s)
- Xiao Ma
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), China
| | - Kevin B Johnson
- Department of Ocean Engineering and Marine Sciences, Florida Institute of Technology, Melbourne, FL, United States
| | - Bowei Gu
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China; University of Chinese Academy of Sciences, Beijing, China
| | - Hao Zhang
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), China
| | - Gang Li
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), China
| | - Xiaoping Huang
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), China
| | - Xiaomin Xia
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), China.
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9
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Li X, Yang M, Mu T, Miao D, Liu J, Xing J. Composition and key-influencing factors of bacterial communities active in sulfur cycling of soda lake sediments. Arch Microbiol 2022; 204:317. [PMID: 35567694 DOI: 10.1007/s00203-022-02925-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 01/20/2022] [Accepted: 04/15/2022] [Indexed: 11/28/2022]
Abstract
Bacteria are important participants in sulfur cycle of the extremely haloalkaline environment, e.g. soda lake. The effects of physicochemical factors on the composition of sulfide-oxidizing bacteria (SOB) and sulfate-reducing bacteria (SRB) in soda lake have remained elusive. Here, we surveyed the community structure of total bacteria, SOB and SRB based on 16S rRNA, soxB and dsrB gene sequencing, respectively, in five soda lakes with different physicochemical factors. The results showed that the dominant bacteria belonged to the phyla Proteobacteria, Bacteroidetes, Halanaerobiaeota, Firmicutes and Actinobacteria. SOB and SRB were widely distributed in lakes with different physicochemical characteristics, and the community composition were different. In general, salinity and inorganic nitrogen sources (NH4+-N, NO3--N) were the most significant factors. Specifically, the communities of SOB, mainly including Thioalkalivibrio, Burkholderia, Paracoccus, Bradyrhizobium, and Hydrogenophaga genera, were remarkably influenced by the levels of NH4+-N and salinity. Yet, for SRB communities, including Desulfurivibrio, Candidatus Electrothrix, Desulfonatronospira, Desulfonatronum, Desulfonatronovibrio, Desulfonatronobacter and so on, the most significant determinants were salinity and NO3--N. Besides, Rhodoplanes played a significant role in the interaction between SOB and SRB. From our results, the knowledge regarding the community structures of SOB and SRB in extremely haloalkaline environment was extended.
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Affiliation(s)
- Xiangyuan Li
- CAS Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China.,College of Bioscience and Bioengineering, Hebei University of Science and Technology, Shijiazhuang, 050018, Hebei, China
| | - Maohua Yang
- CAS Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China.
| | - Tingzhen Mu
- CAS Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China
| | - Delu Miao
- CAS Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China
| | - Jinlong Liu
- College of Bioscience and Bioengineering, Hebei University of Science and Technology, Shijiazhuang, 050018, Hebei, China
| | - Jianmin Xing
- CAS Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China
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10
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Al Disi ZA, Zouari N, Attia E, Al-Asali M, Al Saad Al-Kuwari H, Sadooni F, Dittrich M, Bontognali TRR. Systematic laboratory approach to produce Mg-rich carbonates at low temperature. RSC Adv 2021; 11:37029-37039. [PMID: 35496424 PMCID: PMC9043586 DOI: 10.1039/d1ra06206a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Accepted: 11/10/2021] [Indexed: 01/04/2023] Open
Abstract
Dolomite is a common Mg-rich carbonate in the geological record, but the mechanism of its formation remains unclear. At low temperature, the incorporation of magnesium ions into the carbonate minerals necessary to form dolomite is kinetically inhibited. Over the decades, several factors that possibly allow for overcoming this kinetic barrier have been proposed, and their effectiveness debated. Here, we present the results of a large number of laboratory precipitation experiments that have been designed to identify and compare the factors that promote the formation of Mg-rich carbonates. Under the tested conditions, the most interesting observations include: (1) from solutions that mimic evaporitic seawater, the maximum mol% of Mg incorporated in high Mg calcite is 35, (2) carbonates with a mol% of Mg above 40 were obtained exclusively in the presence of organic molecules, (3) no correlation was observed between the charge of the organic molecules and the incorporation of Mg, (4) the mode (i.e., slow vs. fast mixing) used to add carbonate to the solution obtaining supersaturation has a significant impact on the forming mineral phase (aragonite vs. nesquehonite vs. high Mg calcite) and its Mg content. These findings allow for a more informed evaluation of the existing models for dolomite formation, which are based on the study of natural environments and ancient sedimentary sequences. Carbonates with a mol% of Mg above 40 were obtained exclusively in the presence of organic molecules. The mode used to add carbonate to the solution obtaining supersaturation has a significant impact on the forming mineral phase.![]()
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Affiliation(s)
- Zulfa Ali Al Disi
- Environmental Sciences Program, Department of Biological & Environmental Sciences, College of Arts Sciences, Qatar University P. O. Box 2713 Doha Qatar
| | - Nabil Zouari
- Environmental Sciences Program, Department of Biological & Environmental Sciences, College of Arts Sciences, Qatar University P. O. Box 2713 Doha Qatar
| | - Essam Attia
- Central Laboratory Unit, Qatar University P. O. Box 2713 Doha Qatar
| | - Mazen Al-Asali
- Environmental Science Centre, Qatar University P. O. Box 2713 Doha Qatar
| | | | - Fadhil Sadooni
- Environmental Science Centre, Qatar University P. O. Box 2713 Doha Qatar
| | - Maria Dittrich
- Environmental Science Centre, Qatar University P. O. Box 2713 Doha Qatar.,Department of Physical and Environmental Sciences, University of Toronto Scarborough 1265 Military Trail Toronto M1C 1A4 Canada
| | - Tomaso R R Bontognali
- Environmental Science Centre, Qatar University P. O. Box 2713 Doha Qatar.,Space Exploration Institute (SPACE-X) 68 Faubourg de l'Hopital 2000 Neuchatel Switzerland.,Department of Environmental Sciences, University of Basel Klingelbergstrasse 27 4056 Basel Switzerland
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11
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Lach J, Jęcz P, Strapagiel D, Matera-Witkiewicz A, Stączek P. The Methods of Digging for "Gold" within the Salt: Characterization of Halophilic Prokaryotes and Identification of Their Valuable Biological Products Using Sequencing and Genome Mining Tools. Genes (Basel) 2021; 12:genes12111756. [PMID: 34828362 PMCID: PMC8619533 DOI: 10.3390/genes12111756] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 10/18/2021] [Accepted: 10/30/2021] [Indexed: 02/06/2023] Open
Abstract
Halophiles, the salt-loving organisms, have been investigated for at least a hundred years. They are found in all three domains of life, namely Archaea, Bacteria, and Eukarya, and occur in saline and hypersaline environments worldwide. They are already a valuable source of various biomolecules for biotechnological, pharmaceutical, cosmetological and industrial applications. In the present era of multidrug-resistant bacteria, cancer expansion, and extreme environmental pollution, the demand for new, effective compounds is higher and more urgent than ever before. Thus, the unique metabolism of halophilic microorganisms, their low nutritional requirements and their ability to adapt to harsh conditions (high salinity, high pressure and UV radiation, low oxygen concentration, hydrophobic conditions, extreme temperatures and pH, toxic compounds and heavy metals) make them promising candidates as a fruitful source of bioactive compounds. The main aim of this review is to highlight the nucleic acid sequencing experimental strategies used in halophile studies in concert with the presentation of recent examples of bioproducts and functions discovered in silico in the halophile's genomes. We point out methodological gaps and solutions based on in silico methods that are helpful in the identification of valuable bioproducts synthesized by halophiles. We also show the potential of an increasing number of publicly available genomic and metagenomic data for halophilic organisms that can be analysed to identify such new bioproducts and their producers.
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Affiliation(s)
- Jakub Lach
- Department of Molecular Microbiology, Faculty of Biology and Environmental Protection, University of Lodz, 93-338 Lodz, Poland; (P.J.); (P.S.)
- Biobank Lab, Department of Molecular Biophysics, Faculty of Environmental Protection, University of Lodz, 93-338 Lodz, Poland;
- Correspondence:
| | - Paulina Jęcz
- Department of Molecular Microbiology, Faculty of Biology and Environmental Protection, University of Lodz, 93-338 Lodz, Poland; (P.J.); (P.S.)
| | - Dominik Strapagiel
- Biobank Lab, Department of Molecular Biophysics, Faculty of Environmental Protection, University of Lodz, 93-338 Lodz, Poland;
| | - Agnieszka Matera-Witkiewicz
- Screening Laboratory of Biological Activity Tests and Collection of Biological Material, Faculty of Pharmacy, Wroclaw Medical University, 50-368 Wroclaw, Poland;
| | - Paweł Stączek
- Department of Molecular Microbiology, Faculty of Biology and Environmental Protection, University of Lodz, 93-338 Lodz, Poland; (P.J.); (P.S.)
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12
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Phillips AA, Speth DR, Miller LG, Wang XT, Wu F, Medeiros PM, Monteverde DR, Osburn MR, Berelson WM, Betts HL, Wijker RS, Mullin SW, Johnson HA, Orphan VJ, Fischer WW, Sessions AL. Microbial succession and dynamics in meromictic Mono Lake, California. GEOBIOLOGY 2021; 19:376-393. [PMID: 33629529 PMCID: PMC8359280 DOI: 10.1111/gbi.12437] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 11/18/2020] [Accepted: 02/08/2021] [Indexed: 05/30/2023]
Abstract
Mono Lake is a closed-basin, hypersaline, alkaline lake located in Eastern Sierra Nevada, California, that is dominated by microbial life. This unique ecosystem offers a natural laboratory for probing microbial community responses to environmental change. In 2017, a heavy snowpack and subsequent runoff led Mono Lake to transition from annually mixed (monomictic) to indefinitely stratified (meromictic). We followed microbial succession during this limnological shift, establishing a two-year (2017-2018) water-column time series of geochemical and microbiological data. Following meromictic conditions, anoxia persisted below the chemocline and reduced compounds such as sulfide and ammonium increased in concentration from near 0 to ~400 and ~150 µM, respectively, throughout 2018. We observed significant microbial succession, with trends varying by water depth. In the epilimnion (above the chemocline), aerobic heterotrophs were displaced by phototrophic genera when a large bloom of cyanobacteria appeared in fall 2018. Bacteria in the hypolimnion (below the chemocline) had a delayed, but systematic, response reflecting colonization by sediment "seed bank" communities. Phototrophic sulfide-oxidizing bacteria appeared first in summer 2017, followed by microbes associated with anaerobic fermentation in spring 2018, and eventually sulfate-reducing taxa by fall 2018. This slow shift indicated that multi-year meromixis was required to establish a sulfate-reducing community in Mono Lake, although sulfide oxidizers thrive throughout mixing regimes. The abundant green alga Picocystis remained the dominant primary producer during the meromixis event, abundant throughout the water column including in the hypolimnion despite the absence of light and prevalence of sulfide. Our study adds to the growing literature describing microbial resistance and resilience during lake mixing events related to climatic events and environmental change.
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Affiliation(s)
- Alexandra A. Phillips
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCAUSA
| | - Daan R. Speth
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCAUSA
| | - Laurence G. Miller
- United States Geological Survey, Earth Systems Process DivisionMenlo ParkCAUSA
| | - Xingchen T. Wang
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCAUSA
- Department of Earth and Environmental SciencesBoston CollegeChestnut HillMAUSA
| | - Fenfang Wu
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCAUSA
| | | | - Danielle R. Monteverde
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCAUSA
| | - Magdalena R. Osburn
- Department of Earth and Planetary SciencesNorthwestern UniversityEvanstonILUSA
| | - William M. Berelson
- Department of Earth SciencesUniversity of Southern CaliforniaLos AngelesCAUSA
| | | | - Reto S. Wijker
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCAUSA
| | - Sean W. Mullin
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCAUSA
| | - Hope A. Johnson
- Department of Biological ScienceCalifornia State University FullertonFullertonCAUSA
| | - Victoria J. Orphan
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCAUSA
| | - Woodward W. Fischer
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCAUSA
| | - Geobiology Course 2017
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCAUSA
| | - Geobiology Course 2018
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCAUSA
| | - Alex L. Sessions
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCAUSA
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13
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Cifuentes GR, Jiménez-Millán J, Quevedo CP, Gálvez A, Castellanos-Rozo J, Jiménez-Espinosa R. Trace element fixation in sediments rich in organic matter from a saline lake in tropical latitude with hydrothermal inputs (Sochagota Lake, Colombia): The role of bacterial communities. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 762:143113. [PMID: 33131835 DOI: 10.1016/j.scitotenv.2020.143113] [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: 08/21/2020] [Revised: 10/13/2020] [Accepted: 10/13/2020] [Indexed: 06/11/2023]
Abstract
We studied the relationships between the trace element concentration in sediments from a saline lake at a tropical latitude (Sochagota Lake, Colombia) containing hydrothermal and anthropic inputs with the organic matter content, the mineral assemblage composition and the activity of the bacterial communities of the sediments. Organic matter-poor sediments (TOC < 0.7%) with quartz and kaolinite near the southern entrance of the lake were enriched in Zr (up to 603 mg/kg) and some major detrital elements (Na, Ti, Al and Si). Fine-sized clay-rich sediments deposited in the deep zones of the lake (central and northern segments) were characterized by substantial organic matter (up to 11.10%) and the crystallization of S-bearing minerals, clay mineral mixed layers and illite. These sediments were enriched in S, Fe, Zn, Mo, Rb, Co, K, Cr, Sb, Ni, As, Ba, Cu, Mn, Pb, P, Mg, and Sr. The presence of Fe sulfide nanoparticles enriched in heavy metals encrusting microbial cells and a dominant sulfate-reducing bacteria (SRB) community (Desulfatiglans, Desulfobacterales and Sva0485) suggested that the precipitation of the hydrothermal S and the accumulation of trace elements in the sediments was regulated by SRB activity. The crystallization of S°, barite and calcite and the good correlations between Ba, Sr and Ca indicated that previously precipitated sulfide can be oxidized by the activity of a relevant sulfur-oxidizing bacterial community (Thioalkalimicrobium, Sulfurovum, Arcobacter and Sulfurimonas), possibly facilitating the release of the metals.
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Affiliation(s)
- Gabriel Ricardo Cifuentes
- Faculty of Sciences and Engineering, Water Resources Research Group, University of Boyacá, 150003 Tunja, Colombia
| | - Juan Jiménez-Millán
- Department of Geology and CEACTEMA, University of Jaén, Campus Las Lagunillas, 23071 Jaén, Spain.
| | - Claudia Patricia Quevedo
- Faculty of Sciences and Engineering, Water Resources Research Group, University of Boyacá, 150003 Tunja, Colombia
| | - Antonio Gálvez
- Microbiology Division, Department of Health Sciences, Campus Las Lagunillas, 23071 Jaén, Spain
| | - José Castellanos-Rozo
- Department of Biology and Microbiology, Faculty of Sciences and Engineering, Environmental Management Group, University of Boyacá, 150003 Tunja, Colombia
| | - Rosario Jiménez-Espinosa
- Department of Geology and CEACTEMA, University of Jaén, Campus Las Lagunillas, 23071 Jaén, Spain
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14
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Aljahdali NH, Sanad YM, Han J, Foley SL. Current knowledge and perspectives of potential impacts of Salmonella enterica on the profile of the gut microbiota. BMC Microbiol 2020; 20:353. [PMID: 33203384 PMCID: PMC7673091 DOI: 10.1186/s12866-020-02008-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 10/12/2020] [Indexed: 12/27/2022] Open
Abstract
In the past decade, the initial studies of the gut microbiota started focusing on the correlation of the composition of the gut microbiota and the health or diseases of the host, and there are extensive literature reviews pertaining to this theme. However, little is known about the association between the microbiota, the host, and pathogenic bacteria, such as Salmonella enterica, which is among the most important foodborne pathogens and identified as the source of multiple outbreaks linked to contaminated foods causing salmonellosis. Secretion systems, flagella, fimbriae, endotoxins, and exotoxins are factors that play the most important roles in the successful infection of the host cell by Salmonella. Infections with S. enterica, which is a threat to human health, can alter the genomic, taxonomic, and functional traits of the gut microbiota. The purpose of this review is to outline the state of knowledge on the impacts of S. enterica on the intestinal microbiota and highlight the need to identify the gut bacteria that could contribute to salmonellosis.
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Affiliation(s)
- Nesreen H Aljahdali
- Division of Microbiology, National Center for Toxicological Research, U.S. Food and Drug Administration, 3900 NCTR Rd, Jefferson, AR, 72079, USA.,Biological Science Department, College of Science, King Abdul-Aziz University, Jeddah, Saudi Arabia
| | - Yasser M Sanad
- Division of Microbiology, National Center for Toxicological Research, U.S. Food and Drug Administration, 3900 NCTR Rd, Jefferson, AR, 72079, USA.,Department of Agriculture, University of Arkansas, Pine Bluff, AR, USA.,Department of Parasitology and Animal Diseases, Veterinary Research Division, National Research Centre, Giza, Egypt
| | - Jing Han
- Division of Microbiology, National Center for Toxicological Research, U.S. Food and Drug Administration, 3900 NCTR Rd, Jefferson, AR, 72079, USA
| | - Steven L Foley
- Division of Microbiology, National Center for Toxicological Research, U.S. Food and Drug Administration, 3900 NCTR Rd, Jefferson, AR, 72079, USA.
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15
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Szabó A, Korponai K, Somogyi B, Vajna B, Vörös L, Horváth Z, Boros E, Szabó-Tugyi N, Márialigeti K, Felföldi T. Grazing pressure-induced shift in planktonic bacterial communities with the dominance of acIII-A1 actinobacterial lineage in soda pans. Sci Rep 2020; 10:19871. [PMID: 33199773 PMCID: PMC7669872 DOI: 10.1038/s41598-020-76822-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 09/18/2020] [Indexed: 11/23/2022] Open
Abstract
Astatic soda pans of the Pannonian Steppe are unique environments with respect to their multiple extreme physical and chemical characteristics (high daily water temperature fluctuation, high turbidity, alkaline pH, salinity, polyhumic organic carbon concentration, hypertrophic state and special ionic composition). However, little is known about the seasonal dynamics of the bacterial communities inhabiting these lakes and the role of environmental factors that have the main impact on their structure. Therefore, two soda pans were sampled monthly between April 2013 and July 2014 to reveal changes in the planktonic community. By late spring in both years, a sudden shift in the community structure was observed, the previous algae-associated bacterial communities had collapsed, resulting the highest ratio of Actinobacteria within the bacterioplankton (89%, with the dominance of acIII-A1 lineage) ever reported in the literature. Before these peaks, an extremely high abundance (> 10,000 individuum l-1) of microcrustaceans (Moina brachiata and Arctodiaptomus spinosus) was observed. OTU-based statistical approaches showed that in addition to algal blooms and water-level fluctuations, zooplankton densities had the strongest effect on the composition of bacterial communities. In these extreme environments, this implies a surprisingly strong, community-shaping top-down role of microcrustacean grazers.
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Affiliation(s)
- Attila Szabó
- Department of Microbiology, ELTE Eötvös Loránd University, Pázmány Péter stny. 1/C, Budapest, 1117, Hungary.
| | - Kristóf Korponai
- Department of Microbiology, ELTE Eötvös Loránd University, Pázmány Péter stny. 1/C, Budapest, 1117, Hungary
| | - Boglárka Somogyi
- Centre for Ecological Research, Balaton Limnological Institute, Klebelsberg Kunó u. 3, Tihany, 8237, Hungary
| | - Balázs Vajna
- Department of Microbiology, ELTE Eötvös Loránd University, Pázmány Péter stny. 1/C, Budapest, 1117, Hungary
| | - Lajos Vörös
- Centre for Ecological Research, Balaton Limnological Institute, Klebelsberg Kunó u. 3, Tihany, 8237, Hungary
| | - Zsófia Horváth
- Centre for Ecological Research, Balaton Limnological Institute, Klebelsberg Kunó u. 3, Tihany, 8237, Hungary
| | - Emil Boros
- Centre for Ecological Research, Danube Research Institute, Karolina út 29, Budapest, 1113, Hungary
| | - Nóra Szabó-Tugyi
- Centre for Ecological Research, Balaton Limnological Institute, Klebelsberg Kunó u. 3, Tihany, 8237, Hungary
| | - Károly Márialigeti
- Department of Microbiology, ELTE Eötvös Loránd University, Pázmány Péter stny. 1/C, Budapest, 1117, Hungary
| | - Tamás Felföldi
- Department of Microbiology, ELTE Eötvös Loránd University, Pázmány Péter stny. 1/C, Budapest, 1117, Hungary
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16
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Xu W, Gao Q, He C, Shi Q, Hou ZQ, Zhao HZ. Using ESI FT-ICR MS to Characterize Dissolved Organic Matter in Salt Lakes with Different Salinity. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:12929-12937. [PMID: 33040523 DOI: 10.1021/acs.est.0c01681] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Dissolved organic matter (DOM) composition in salt lakes is critical for water quality and aquatic ecology, and the salinization of salt lakes affects the DOM composition. To the best of our knowledge, no study has explored the effects of salinity on salt lake DOM composition at the molecular level. In this work, we selected Qinghai Lake (QHL) and Daihai Lake (DHL) as typical saline lakes. The two lakes have similar geographical and climatic conditions, and the salinity of QHL is higher than that of DHL. Fourier transform ion cyclotron resonance mass spectrometry coupled with electrospray ionization was applied to compare the DOM molecular composition in the two lakes. At higher salinity, the DOM showed larger average molecular weight, higher oxidation degree, and lower aromaticity. Moreover, the proportion of DOM that is vulnerable to microbial degradation (e.g., lipids), photo-degradation (e.g., aromatic structures), or both processes (e.g., carbohydrates and unsaturated hydrocarbons) reduced at higher salinity. On the contrary, compounds that are refractory to microbial degradation (e.g., lignins/CRAM-like structures and tannins) or photo-degradation (e.g., aliphatic compounds) accumulated. Our study provides a useful and unique method to study DOM molecular composition in salt lakes with different salinity and is helpful to understand DOM transformation during the salinization of salt lakes.
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Affiliation(s)
- Wei Xu
- Key Laboratory of Water and Sediment Sciences (Ministry of Education), College of Environmental Sciences and Engineering, Peking University, Beijing 100871, People's Republic of China
| | - Qiang Gao
- State Key Lab Plateau Ecology and Agriculture, Qinghai University, Xining 810016, People's Republic of China
| | - Chen He
- State Key Laboratory of Heavy Oil Processing, Petroleum Molecular Engineering Center (PMEC), China University of Petroleum, Beijing 102249, People's Republic of China
| | - Quan Shi
- State Key Laboratory of Heavy Oil Processing, Petroleum Molecular Engineering Center (PMEC), China University of Petroleum, Beijing 102249, People's Republic of China
| | - Zheng-Qing Hou
- College of Chemistry and Chemical Engineering, China University of Petroleum, Qingdao 266555, People's Republic of China
| | - Hua-Zhang Zhao
- Key Laboratory of Water and Sediment Sciences (Ministry of Education), College of Environmental Sciences and Engineering, Peking University, Beijing 100871, People's Republic of China
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17
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Lavrentyeva EV, Erdyneeva EB, Banzaraktsaeva TG, Kotsyurbenko OR, Baturina OA, Khakhinov VV, Kozyreva LP. Prokaryotic Diversity in the Biotopes of the Gudzhirganskoe Saline Lake (Barguzin Valley, Russia). Microbiology (Reading) 2020. [DOI: 10.1134/s0026261720030157] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
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18
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An evaluation of the core bacterial communities associated with hypersaline environments in the Qaidam Basin, China. Arch Microbiol 2020; 202:2093-2103. [PMID: 32488562 DOI: 10.1007/s00203-020-01927-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 05/15/2020] [Accepted: 05/26/2020] [Indexed: 12/31/2022]
Abstract
Hypersaline lakes and saltern areas are important industrial and biodiversity resources in the Qaidam Basin of China that reside at > 2600 m asl. Most hypersaline environments in this area are characterized by saturated salinity (~ 300 g/L salinity), nearly neutral pH, intense ultraviolet radiation, and extremely variable temperature fluctuations. The core bacterial communities associated with these stressful environments have nevertheless remained uninvestigated. 16S rRNA gene Illumina sequencing analyses revealed that the bacterial communities were dominated by core lineages including the Proteobacteria (39.4-64.6%) and the Firmicutes (17.0-42.7%). However, the relative abundances of common lineages, and especially the five most abundant taxa of Pseudomonas, Lactococcus, Anoxybacillus, Acinetobacter, and Brevundimonas, were highly variable across communities and closely associated with hypersaline characteristics in the samples. Network analysis revealed the presence of co-occurrence high relative abundance taxa (cluster I) that were highly correlated across all hypersaline samples. Additionally, temperature, total organic carbon, K+, and Mg2+ correlated highest with taxonomic distributions across communities. These results highlight the potential mechanisms that could underlie survival and adaptation to these extreme hypersaline ecosystems.
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19
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Abdel Samad R, Al Disi Z, Mohammad Ashfaq MY, Wahib SM, Zouari N. The use of principle component analysis and MALDI-TOF MS for the differentiation of mineral forming Virgibacillus and Bacillus species isolated from sabkhas. RSC Adv 2020; 10:14606-14616. [PMID: 35497157 PMCID: PMC9051895 DOI: 10.1039/d0ra01229g] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Accepted: 04/01/2020] [Indexed: 01/23/2023] Open
Abstract
Occurrence of mineral forming and other bacteria in mats is well demonstrated. However, their high diversity shown by ribotyping has not been explained, although it could explain the diversity of formed minerals. Common biomarkers as well as phylogenic relationships are useful tools for clustering the isolates and the prediction of their potential role in the natural niche. In this study, a combination of MALDI-TOF MS with PCA was shown to be a powerful tool to categorize 35 mineral forming bacterial isolates isolated from Dohat Faishakh sabkha, northwest of Qatar (23 from decaying mats and 12 from living ones). The 23 strains from decaying mats belong to the Virgibacillus genus as identified by ribotyping and are shown to be highly involved in the formation of protodolomite and a diversity of minerals. They were used as internal references for the categorization of sabkha bacteria. Combination of the isolation of bacteria on selective mineral forming media, their MALDI TOF MS protein profiling and PCA analysis established their relationship in a phylloproteomic dendrogram based on protein biomarkers including m/z 4905, 3265, 5240, 6430, 7765, and 9815. PCA analysis clustered the studied isolates into 3 major clusters, showing strong correspondence to the 3 phylloproteomic groups that were established by the dendrogram. Both clustering analysis means have evidently demonstrated a relationship between known Virgibacillus strains and other related bacteria based on profiling of their synthesized proteins. Thus, larger populations of bacteria in mats can be easily screened for their potential to exhibit certain activities, which is of ecological, environmental and biotechnological significance. Occurrence of mineral forming and other bacteria in mats is well demonstrated.![]()
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Affiliation(s)
- Rim Abdel Samad
- Department of Biological and Environmental Sciences
- College of Arts and Sciences
- Qatar University
- Doha
- Qatar
| | - Zulfa Al Disi
- Department of Biological and Environmental Sciences
- College of Arts and Sciences
- Qatar University
- Doha
- Qatar
| | | | - Sara Mohiddin Wahib
- Department of Biological and Environmental Sciences
- College of Arts and Sciences
- Qatar University
- Doha
- Qatar
| | - Nabil Zouari
- Department of Biological and Environmental Sciences
- College of Arts and Sciences
- Qatar University
- Doha
- Qatar
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20
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The microbial community in filamentous bulking sludge with the ultra-low sludge loading and long sludge retention time in oxidation ditch. Sci Rep 2019; 9:13693. [PMID: 31548550 PMCID: PMC6757048 DOI: 10.1038/s41598-019-50086-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 08/31/2019] [Indexed: 12/20/2022] Open
Abstract
Sludge bulking is a major problem that restricts the development of the activated sludge process. The microbial community responsible for sludge bulking varies depending on water quality and operational conditions. This study analysed the microbial community of bulking sludge in oxidation ditch with ultra-low sludge loading and long sludge retention time using high-throughput sequencing. The study found that the relative abundance of bacterial genus Saprospiraceae_norank was the highest in bulking sludge, reaching 13.39-28.83%, followed by Comamonadaceae_unclassified, Ardenticatenia_norank and Tetrasphaera, with the relative abundance of 4.59-11.08%, 0.52-16.60% and 0.17-8.92% respectively. In contrast, the relative abundance of bacteria that easily caused sludge bulking including Microthrix (0.54-2.47%), Trichococcus (0.32-1.71%), Gordonia (0.14-1.28%), and Thiothrix (0.01-0.06%) were relatively low. Saprospiraceae_norank was predominant and induced sludge bulking in oxidation ditch. The relative abundance of fungal genus Trichosporon was the highest in bulking sludge, reaching 16.95-24.98%, while other fungal genera were Saccharomycetales_unclassified (5.59-14.55%), Ascomycota_norank (1.45-13.51%), Galactomyces (5.23-11.23%), and Debaryomyces (7.69-9.42%), whereas Trichosporon was the dominant fungal genus in bulking sludge. This study reported that excessive Saprospiraceae_norank can induce sludge bulking for the first time, which provides important knowledge to control sludge bulking.
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21
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Ample Arsenite Bio-Oxidation Activity in Bangladesh Drinking Water Wells: A Bonanza for Bioremediation? Microorganisms 2019; 7:microorganisms7080246. [PMID: 31398879 PMCID: PMC6723331 DOI: 10.3390/microorganisms7080246] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 07/26/2019] [Accepted: 07/31/2019] [Indexed: 11/17/2022] Open
Abstract
Millions of people worldwide are at risk of arsenic poisoning from their drinking water. In Bangladesh the problem extends to rural drinking water wells, where non-biological solutions are not feasible. In serial enrichment cultures of water from various Bangladesh drinking water wells, we found transfer-persistent arsenite oxidation activity under four conditions (aerobic/anaerobic; heterotrophic/autotrophic). This suggests that biological decontamination may help ameliorate the problem. The enriched microbial communities were phylogenetically at least as diverse as the unenriched communities: they contained a bonanza of 16S rRNA gene sequences. These related to Hydrogenophaga, Acinetobacter, Dechloromonas, Comamonas, and Rhizobium/Agrobacterium species. In addition, the enriched microbiomes contained genes highly similar to the arsenite oxidase (aioA) gene of chemolithoautotrophic (e.g., Paracoccus sp. SY) and heterotrophic arsenite-oxidizing strains. The enriched cultures also contained aioA phylotypes not detected in the previous survey of uncultivated samples from the same wells. Anaerobic enrichments disclosed a wider diversity of arsenite oxidizing aioA phylotypes than did aerobic enrichments. The cultivatable chemolithoautotrophic and heterotrophic arsenite oxidizers are of great interest for future in or ex-situ arsenic bioremediation technologies for the detoxification of drinking water by oxidizing arsenite to arsenate that should then precipitates with iron oxides. The microbial activities required for such a technology seem present, amplifiable, diverse and hence robust.
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22
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Gavrilov SN, Korzhenkov AA, Kublanov IV, Bargiela R, Zamana LV, Popova AA, Toshchakov SV, Golyshin PN, Golyshina OV. Microbial Communities of Polymetallic Deposits' Acidic Ecosystems of Continental Climatic Zone With High Temperature Contrasts. Front Microbiol 2019; 10:1573. [PMID: 31379766 PMCID: PMC6650587 DOI: 10.3389/fmicb.2019.01573] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 06/24/2019] [Indexed: 12/26/2022] Open
Abstract
Acid mine drainage (AMD) systems are globally widespread and are an important source of metal pollution in riverine and coastal systems. Microbial AMD communities have been extensively studied for their ability to thrive under extremely acidic conditions and for their immense contribution to the dissolution of metal ores. However, little is known on microbial inhabitants of AMD systems subjected to extremely contrasting continental seasonal temperature patterns as opposed to maritime climate zones, experiencing much weaker annual temperature variations. Here, we investigated three types of AMD sites in Eastern Transbaikalia (Russia). In this region, all surface water bodies undergo a deep and long (up to 6 months) freezing, with seasonal temperatures varying between -33 and +24°C, which starkly contrasts the common well-studied AMD environments. We sampled acidic pit lake (Sherlovaya Gora site) located in the area of a polymetallic deposit, acidic drainage water from Bugdaya gold-molybdenum-tungsten deposit and Ulan-Bulak natural acidic spring. These systems showed the abundance of bacteria-derived reads mostly affiliated with Actinobacteria, Acidobacteria, Alpha- and Gammaproteobacteria, chloroplasts, Chloroflexi, Bacteroidetes, and Firmicutes. Furthermore, candidate taxa "Ca. Saccharibacteria" (previously known as TM7), "Ca. Parcubacteria" (OD1) and WPS-2 were represented in substantial quantities (10-20%). Heterotrophy and iron redox cycling can be considered as central processes of carbon and energy flow for majority of detected bacterial taxa. Archaea were detected in low numbers, with Terrestrial Miscellaneous Euryarchaeal Group (TMEG), to be most abundant (3%) in acidic spring Ulan-Bulak. Composition of these communities was found to be typical in comparison to other AMD sites; however, certain groups (as Ignavibacteriae) could be specifically associated with this area. This study provides insight into the microbial diversity patterns in acidic ecosystems formed in areas of polymetallic deposits in extreme continental climate zone with contrasting temperature parameters.
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Affiliation(s)
- Sergey N. Gavrilov
- Laboratory of Metabolism of Extremophiles, Winogradsky Institute of Microbiology, FRC Biotechnology, RAS, Moscow, Russia
| | - Aleksei A. Korzhenkov
- Laboratory of Bioinformatics, Genomics and Genome Editing, NRC Kurchatov Institute, Moscow, Russia
| | - Ilya V. Kublanov
- Laboratory of Metabolism of Extremophiles, Winogradsky Institute of Microbiology, FRC Biotechnology, RAS, Moscow, Russia
| | - Rafael Bargiela
- School of Natural Sciences, Bangor University, Bangor, United Kingdom
| | - Leonid V. Zamana
- Laboratory of Geoecology and Hydrogeochemistry, Institute of Natural Resources, Ecology and Cryology, SB RAS, Chita, Russia
| | - Alexandra A. Popova
- Laboratory of Metabolism of Extremophiles, Winogradsky Institute of Microbiology, FRC Biotechnology, RAS, Moscow, Russia
| | - Stepan V. Toshchakov
- Laboratory of Metabolism of Extremophiles, Winogradsky Institute of Microbiology, FRC Biotechnology, RAS, Moscow, Russia
| | - Peter N. Golyshin
- School of Natural Sciences, Bangor University, Bangor, United Kingdom
- Centre for Environmental Biotechnology, Bangor University, Bangor, United Kingdom
| | - Olga V. Golyshina
- School of Natural Sciences, Bangor University, Bangor, United Kingdom
- Centre for Environmental Biotechnology, Bangor University, Bangor, United Kingdom
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23
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Shurigin V, Hakobyan A, Panosyan H, Egamberdieva D, Davranov K, Birkeland NK. A glimpse of the prokaryotic diversity of the Large Aral Sea reveals novel extremophilic bacterial and archaeal groups. Microbiologyopen 2019; 8:e00850. [PMID: 31058468 PMCID: PMC6741134 DOI: 10.1002/mbo3.850] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Revised: 03/27/2019] [Accepted: 03/27/2019] [Indexed: 01/10/2023] Open
Abstract
During the last five decades, the Aral Sea has gradually changed from a saline water body to a hypersaline lake. Microbial community inhabiting the Aral Sea has been through a succession and continuous adaptation during the last 50 years of increasing salinization, but so far, the microbial diversity has not been explored. Prokaryotic diversity of the Large Aral Sea using cultivation‐independent methods based on determination of environmental 16S rRNA gene sequences revealed a microbial community related to typical marine or (hyper) saline‐adapted Bacteria and Archaea. The archaeal sequences were phylogenetically affiliated with the order Halobacteriales, with a large number of operational taxonomic units constituting a novel cluster in the Haloferacaceae family. Bacterial community analysis indicated a higher diversity with representatives belonging to Proteobacteria, Actinobacteria and Bacteroidetes. Many members of Alphaproteobacteria and Gammaproteobacteria were affiliated with genera like Roseovarius, Idiomarina and Spiribacter which have previously been found in marine or hypersaline waters. The majority of the phylotypes was most closely related to uncultivated organisms and shared less than 97% identity with their closest match in GenBank, indicating a unique community structure in the Large Aral Sea with mostly novel species or genera.
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Affiliation(s)
- Vyacheslav Shurigin
- Department of Biological Sciences, University of Bergen, Bergen, Norway.,Department of Microbiology and Biotechnology, Faculty of Biology, National University of Uzbekistan, Tashkent, Uzbekistan
| | - Anna Hakobyan
- Department of Biological Sciences, University of Bergen, Bergen, Norway.,Department of Biochemistry, Microbiology and Biotechnology, Yerevan State University, Yerevan, Armenia
| | - Hovik Panosyan
- Department of Biochemistry, Microbiology and Biotechnology, Yerevan State University, Yerevan, Armenia
| | - Dilfuza Egamberdieva
- Department of Microbiology and Biotechnology, Faculty of Biology, National University of Uzbekistan, Tashkent, Uzbekistan.,Key Laboratory of Biogeography and Bioresource in Arid Land, Xinjiang Institute of Ecology and Geography, CAS, Urumqi, People's Republic of China.,Leibniz Centre for Agricultural Landscape Research (ZALF), Müncheberg, Germany
| | - Kakhramon Davranov
- Department of Microbiology and Biotechnology, Faculty of Biology, National University of Uzbekistan, Tashkent, Uzbekistan
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24
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Meng D, Li J, Liu T, Liu Y, Yan M, Hu J, Li X, Liu X, Liang Y, Liu H, Yin H. Effects of redox potential on soil cadmium solubility: Insight into microbial community. J Environ Sci (China) 2019; 75:224-232. [PMID: 30473288 DOI: 10.1016/j.jes.2018.03.032] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 03/20/2018] [Accepted: 03/22/2018] [Indexed: 05/08/2023]
Abstract
Understanding the role of microbes in the solubility of cadmium (Cd) is of fundamental importance for remediation of Cd toxicity. The present study aimed to identify the microbes that involved in regulating Cd solubility and to reveal possible mechanisms. Therefore, microbial communities were investigated through high-throughput sequencing approach, the molecular ecological network was constructed and metagenomes were predicted. Our results indicated that redox conditions affected both the solubility of soil Cd and the microbial communities. Anaerobic microbes, such as Anaerolineaceae, did not only play important roles in shaping the microbial community in soils, but might also be involved in regulating the Cd solubility. Two possible mechanisms that how Anaerolineaceae involved in Cd solubility are (1) Anaerolineaceae are important organic matter degraders under anoxic conditions and (2) Anaerolineaceae can co-exist with methane metabolism microbes, while methane metabolism promotes the precipitation of soluble Cd. Thus, application of Anaerolineaceae in bioremediation of soil Cadmium contamination is a potential approach. The study provided a novel insight into the role of microbial community in the regulation of Cd solubility under different redox conditions, and suggested a potential approach for the remediation of soil Cd contamination.
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Affiliation(s)
- Delong Meng
- School of Minerals Processing and Bioengineering, Central South University, Changsha, 410083 China; Key laboratory of Biometallurgy, Ministry of Education, Changsha, 410083 China.
| | - Juan Li
- College of Agronomy, Hunan Agricultural University, Changsha, 410128 China
| | - Tianbo Liu
- College of Plant protection, Hunan Agricultural University, Changsha, 410128 China
| | - Yongjun Liu
- College of Agronomy, Hunan Agricultural University, Changsha, 410128 China
| | - Mingli Yan
- School of Life Science, Hunan University of Science and Technology, Xiangtan, 411201 China
| | - Jin Hu
- School of Minerals Processing and Bioengineering, Central South University, Changsha, 410083 China; Key laboratory of Biometallurgy, Ministry of Education, Changsha, 410083 China
| | - Xiaoqi Li
- School of Minerals Processing and Bioengineering, Central South University, Changsha, 410083 China; Key laboratory of Biometallurgy, Ministry of Education, Changsha, 410083 China
| | - Xueduan Liu
- School of Minerals Processing and Bioengineering, Central South University, Changsha, 410083 China; Key laboratory of Biometallurgy, Ministry of Education, Changsha, 410083 China
| | - Yili Liang
- School of Minerals Processing and Bioengineering, Central South University, Changsha, 410083 China; Key laboratory of Biometallurgy, Ministry of Education, Changsha, 410083 China
| | - Hongwei Liu
- School of Minerals Processing and Bioengineering, Central South University, Changsha, 410083 China; Key laboratory of Biometallurgy, Ministry of Education, Changsha, 410083 China
| | - Huaqun Yin
- School of Minerals Processing and Bioengineering, Central South University, Changsha, 410083 China; Key laboratory of Biometallurgy, Ministry of Education, Changsha, 410083 China.
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25
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Metabolic Capability and Phylogenetic Diversity of Mono Lake during a Bloom of the Eukaryotic Phototroph Picocystis sp. Strain ML. Appl Environ Microbiol 2018; 84:AEM.01171-18. [PMID: 30120120 PMCID: PMC6193381 DOI: 10.1128/aem.01171-18] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 08/04/2018] [Indexed: 02/07/2023] Open
Abstract
Algal blooms in lakes are often associated with anthropogenic eutrophication; however, they can occur without the human introduction of nutrients to a lake. A rare bloom of the alga Picocystis sp. strain ML occurred in the spring of 2016 at Mono Lake, a hyperalkaline lake in California, which was also at the apex of a multiyear-long drought. These conditions presented a unique sampling opportunity to investigate microbiological dynamics and potential metabolic function during an intense natural algal bloom. We conducted a comprehensive molecular analysis along a depth transect near the center of the lake from the surface to a depth of 25 m in June 2016. Across sampled depths, rRNA gene sequencing revealed that Picocystis-associated chloroplasts were found at 40 to 50% relative abundance, greater than values recorded previously. Despite high relative abundances of the photosynthetic oxygenic algal genus Picocystis, oxygen declined below detectable limits below a depth of 15 m, corresponding with an increase in microorganisms known to be anaerobic. In contrast to previously sampled years, both metagenomic and metatranscriptomic data suggested a depletion of anaerobic sulfate-reducing microorganisms throughout the lake's water column. Transcripts associated with photosystem I and II were expressed at both 2 m and 25 m, suggesting that limited oxygen production could occur at extremely low light levels at depth within the lake. Blooms of Picocystis appear to correspond with a loss of microbial activity such as sulfate reduction within Mono Lake, yet microorganisms may survive within the sediment to repopulate the lake water column as the bloom subsides.IMPORTANCE Mono Lake, California, provides a habitat to a unique ecological community that is heavily stressed due to recent human water diversions and a period of extended drought. To date, no baseline information exists from Mono Lake to understand how the microbial community responds to human-influenced drought or algal bloom or what metabolisms are lost in the water column as a consequence of such environmental pressures. While previously identified anaerobic members of the microbial community disappear from the water column during drought and bloom, sediment samples suggest that these microorganisms survive at the lake bottom or in the subsurface. Thus, the sediments may represent a type of seed bank that could restore the microbial community as a bloom subsides. Our work sheds light on the potential photosynthetic activity of the halotolerant alga Picocystis sp. strain ML and how the function and activity of the remainder of the microbial community responds during a bloom at Mono Lake.
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