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Ooi QE, Nguyen CTT, Laloo AE, Koh YZ, Swarup S. Soil-sediment connectivity through Bayesian source tracking in an urban naturalised waterway via microbial and isotopic markers. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 949:175152. [PMID: 39097031 DOI: 10.1016/j.scitotenv.2024.175152] [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: 02/25/2024] [Revised: 06/27/2024] [Accepted: 07/28/2024] [Indexed: 08/05/2024]
Abstract
Riverine sediments are important habitats for microbial activity in naturalised waterways to provide potential ecosystem services that improve stormwater quality. Yet, little is known about the sources of these sediment microbes, and the factors shaping them. This study investigated the dominant source of sediments in a tropical naturalised urban waterway, using two Bayesian methods for microbial and isotopic 13C/15N markers concurrently. Additionally, key factors shaping microbial communities from the surrounding landscape were evaluated. A comprehensive two-year field survey identified source land covers of interest based on topology and soil context. Among these land covers, riverbanks were the dominant source of sediments contribution for both edaphic and microbial components. The physico-chemical environment explains most of the variation in sediment communities compared to inter-location distances and microbial source contribution. As microbes provide ecosystem services important for rewilding waterways, management strategies that establish diverse sediment microbial communities are encouraged. Since riverbanks play a disproportionately important role in material contribution to sediment beds, management practices aimed at controlling soil erosion from riverbanks can improve overall functioning of waterway systems.
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Affiliation(s)
- Qi En Ooi
- National University of Singapore Environmental Research Institute, National University of Singapore, 117411, Singapore; Singapore Centre of Environmental Engineering and Life Sciences, National University of Singapore, Singapore; Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore.
| | - Canh Tien Trinh Nguyen
- Singapore Centre of Environmental Engineering and Life Sciences, National University of Singapore, Singapore; Centre for Radiation Research Education and Innovation, The University of Adelaide, 5005, Australia
| | - Andrew Elohim Laloo
- National University of Singapore Environmental Research Institute, National University of Singapore, 117411, Singapore; Singapore Centre of Environmental Engineering and Life Sciences, National University of Singapore, Singapore.
| | - Yi Zi Koh
- Singapore Centre of Environmental Engineering and Life Sciences, National University of Singapore, Singapore
| | - Sanjay Swarup
- National University of Singapore Environmental Research Institute, National University of Singapore, 117411, Singapore; Singapore Centre of Environmental Engineering and Life Sciences, National University of Singapore, Singapore; Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore.
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Lee H, Hwang K, Cho A, Kim S, Kim M, Morgan-Kiss R, Priscu JC, Kim KM, Kim OS. Microbial assemblages and associated biogeochemical processes in Lake Bonney, a permanently ice-covered lake in the McMurdo Dry Valleys, Antarctica. ENVIRONMENTAL MICROBIOME 2024; 19:60. [PMID: 39160591 PMCID: PMC11334312 DOI: 10.1186/s40793-024-00605-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Accepted: 08/13/2024] [Indexed: 08/21/2024]
Abstract
BACKGROUND Lake Bonney, which is divided into a west lobe (WLB) and an east lobe (ELB), is a perennially ice-covered lake located in the McMurdo Dry Valleys of Antarctica. Despite previous reports on the microbial community dynamics of ice-covered lakes in this region, there is a paucity of information on the relationship between microbial genomic diversity and associated nutrient cycling. Here, we applied gene- and genome-centric approaches to investigate the microbial ecology and reconstruct microbial metabolic potential along the depth gradient in Lake Bonney. RESULTS Lake Bonney is strongly chemically stratified with three distinct redox zones, yielding different microbial niches. Our genome enabled approach revealed that in the sunlit and relatively freshwater epilimnion, oxygenic photosynthetic production by the cyanobacterium Pseudanabaena and a diversity of protists and microalgae may provide new organic carbon to the environment. CO-oxidizing bacteria, such as Acidimicrobiales, Nanopelagicales, and Burkholderiaceae were also prominent in the epilimnion and their ability to oxidize carbon monoxide to carbon dioxide may serve as a supplementary energy conservation strategy. In the more saline metalimnion of ELB, an accumulation of inorganic nitrogen and phosphorus supports photosynthesis despite relatively low light levels. Conversely, in WLB the release of organic rich subglacial discharge from Taylor Glacier into WLB would be implicated in the possible high abundance of heterotrophs supported by increased potential for glycolysis, beta-oxidation, and glycoside hydrolase and may contribute to the growth of iron reducers in the dark and extremely saline hypolimnion of WLB. The suboxic and subzero temperature zones beneath the metalimnia in both lobes supported microorganisms capable of utilizing reduced nitrogens and sulfurs as electron donors. Heterotrophs, including nitrate reducing sulfur oxidizing bacteria, such as Acidimicrobiales (MAG72) and Salinisphaeraceae (MAG109), and denitrifying bacteria, such as Gracilimonas (MAG7), Acidimicrobiales (MAG72) and Salinisphaeraceae (MAG109), dominated the hypolimnion of WLB, whereas the environmental harshness of the hypolimnion of ELB was supported by the relatively low in metabolic potential, as well as the abundance of halophile Halomonas and endospore-forming Virgibacillus. CONCLUSIONS The vertical distribution of microbially driven C, N and S cycling genes/pathways in Lake Bonney reveals the importance of geochemical gradients to microbial diversity and biogeochemical cycles with the vertical water column.
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Affiliation(s)
- Hanbyul Lee
- Division of Life Sciences, Korea Polar Research Institute, Yeonsu-Gu, Incheon, 21990, Republic of Korea
| | - Kyuin Hwang
- Division of Life Sciences, Korea Polar Research Institute, Yeonsu-Gu, Incheon, 21990, Republic of Korea
| | - Ahnna Cho
- Division of Life Sciences, Korea Polar Research Institute, Yeonsu-Gu, Incheon, 21990, Republic of Korea
| | - Soyeon Kim
- Division of Life Sciences, Korea Polar Research Institute, Yeonsu-Gu, Incheon, 21990, Republic of Korea
| | - Minkyung Kim
- Division of Life Sciences, Korea Polar Research Institute, Yeonsu-Gu, Incheon, 21990, Republic of Korea
| | | | - John C Priscu
- Emeritus, Department of Land Resources and Environmental Sciences, Montana State University, Bozeman, MT, 59717, USA
| | - Kyung Mo Kim
- Division of Life Sciences, Korea Polar Research Institute, Yeonsu-Gu, Incheon, 21990, Republic of Korea
| | - Ok-Sun Kim
- Division of Life Sciences, Korea Polar Research Institute, Yeonsu-Gu, Incheon, 21990, Republic of Korea.
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Gray DA, Wang B, Sidarta M, Cornejo FA, Wijnheijmer J, Rani R, Gamba P, Turgay K, Wenzel M, Strahl H, Hamoen LW. Membrane depolarization kills dormant Bacillus subtilis cells by generating a lethal dose of ROS. Nat Commun 2024; 15:6877. [PMID: 39128925 PMCID: PMC11317493 DOI: 10.1038/s41467-024-51347-0] [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: 08/12/2021] [Accepted: 08/02/2024] [Indexed: 08/13/2024] Open
Abstract
The bactericidal activity of several antibiotics partially relies on the production of reactive oxygen species (ROS), which is generally linked to enhanced respiration and requires the Fenton reaction. Bacterial persister cells, an important cause of recurring infections, are tolerant to these antibiotics because they are in a dormant state. Here, we use Bacillus subtilis cells in stationary phase, as a model system of dormant cells, to show that pharmacological induction of membrane depolarization enhances the antibiotics' bactericidal activity and also leads to ROS production. However, in contrast to previous studies, this results primarily in production of superoxide radicals and does not require the Fenton reaction. Genetic analyzes indicate that Rieske factor QcrA, the iron-sulfur subunit of respiratory complex III, seems to be a primary source of superoxide radicals. Interestingly, the membrane distribution of QcrA changes upon membrane depolarization, suggesting a dissociation of complex III. Thus, our data reveal an alternative mechanism by which antibiotics can cause lethal ROS levels, and may partially explain why membrane-targeting antibiotics are effective in eliminating persisters.
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Affiliation(s)
- Declan A Gray
- Centre for Bacterial Cell Biology, Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Baddiley-Clark Building, Newcastle upon Tyne, NE2 4AX, UK
- Centre for Antibiotic Resistance Research in Gothenburg (CARe), Gothenburg, Sweden
- Department of Infectious Diseases, Institute of Biomedicine, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Biwen Wang
- Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, C3.108, 1098 XH, Amsterdam, The Netherlands
| | - Margareth Sidarta
- Centre for Antibiotic Resistance Research in Gothenburg (CARe), Gothenburg, Sweden
- Division of Chemical Biology, Department of Life Sciences, Chalmers University of Technology, Kemigården 4, 412 96, Gothenburg, Sweden
| | - Fabián A Cornejo
- Max Planck Unit for the Science of Pathogens, Charitéplatz 1, 10117, Berlin, Germany
| | - Jurian Wijnheijmer
- Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, C3.108, 1098 XH, Amsterdam, The Netherlands
| | - Rupa Rani
- Centre for Antibiotic Resistance Research in Gothenburg (CARe), Gothenburg, Sweden
- Division of Chemical Biology, Department of Life Sciences, Chalmers University of Technology, Kemigården 4, 412 96, Gothenburg, Sweden
| | - Pamela Gamba
- Centre for Bacterial Cell Biology, Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Baddiley-Clark Building, Newcastle upon Tyne, NE2 4AX, UK
- Charles River Laboratories, Keele Science Park, Keele, ST5 5SP, UK
| | - Kürşad Turgay
- Max Planck Unit for the Science of Pathogens, Charitéplatz 1, 10117, Berlin, Germany
- Leibniz Universität Hannover, Institut für Mikrobiologie, Herrenhäuser Str. 2, 30419, Hannover, Germany
| | - Michaela Wenzel
- Centre for Antibiotic Resistance Research in Gothenburg (CARe), Gothenburg, Sweden
- Division of Chemical Biology, Department of Life Sciences, Chalmers University of Technology, Kemigården 4, 412 96, Gothenburg, Sweden
| | - Henrik Strahl
- Centre for Bacterial Cell Biology, Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Baddiley-Clark Building, Newcastle upon Tyne, NE2 4AX, UK
| | - Leendert W Hamoen
- Centre for Bacterial Cell Biology, Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Baddiley-Clark Building, Newcastle upon Tyne, NE2 4AX, UK.
- Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, C3.108, 1098 XH, Amsterdam, The Netherlands.
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Zhang C, Liu J, Liu X, Xu Y, Gan Q, Cheng Q, Liu W, Gao X, Wu S. Glutamine enhances pneumococcal growth under methionine semi-starvation by elevating intracellular pH. Front Microbiol 2024; 15:1430038. [PMID: 39044959 PMCID: PMC11263215 DOI: 10.3389/fmicb.2024.1430038] [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: 05/09/2024] [Accepted: 06/28/2024] [Indexed: 07/25/2024] Open
Abstract
Introduction Bacteria frequently encounter nutrient limitation in nature. The ability of living in this nutrient shortage environment is vital for bacteria to preserve their population and important for some pathogenic bacteria to cause infectious diseases. Usually, we study how bacteria survive after nutrient depletion, a total starvation condition when bacteria almost cease growth and try to survive. However, nutrient limitation may not always lead to total starvation. Methods Bacterial adaptation to nutrient shortage was studied by determining bacterial growth curves, intracellular pH, intracellular amino acid contents, gene transcription, protein expression, enzyme activity, and translation and replication activities. Results No exogenous supply of methionine results in growth attenuation of Streptococcus pneumoniae, a human pathogen. In this paper, we refer to this inhibited growth state between ceased growth under total starvation and full-speed growth with full nutrients as semi-starvation. Similar to total starvation, methionine semi-starvation also leads to intracellular acidification. Surprisingly, it is intracellular acidification but not insufficient methionine synthesis that causes growth attenuation under methionine semi-starvation. With excessive glutamine supply in the medium, intracellular methionine level was not changed, while bacterial intracellular pH was elevated to ~ 7.6 (the optimal intracellular pH for pneumococcal growth) by glutamine deamination, and bacterial growth under semi-starvation was restored fully. Our data suggest that intracellular acidification decreases translation level and glutamine supply increases intracellular pH to restore translation level, thus restoring bacterial growth. Discussion This growth with intracellular pH adjustment by glutamine is a novel strategy we found for bacterial adaptation to nutrient shortage, which may provide new drug targets to inhibit growth of pathogenic bacteria under semi-starvation.
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Affiliation(s)
- Chengwang Zhang
- Department of Basic Medical Science, School of Medicine, Lishui University, Lishui, Zhejiang, China
| | - Juncheng Liu
- Department of Basic Medical Science, School of Medicine, Lishui University, Lishui, Zhejiang, China
| | - Xiaohui Liu
- National Protein Science Facility, Tsinghua University, Beijing, China
- School of Life Sciences, Tsinghua University, Beijing, China
| | - Yueyu Xu
- Department of Basic Medical Science, School of Medicine, Lishui University, Lishui, Zhejiang, China
| | - Qingxiu Gan
- Department of Basic Medical Science, School of Medicine, Lishui University, Lishui, Zhejiang, China
| | - Qinqian Cheng
- Department of Basic Medical Science, School of Medicine, Lishui University, Lishui, Zhejiang, China
| | - Weiping Liu
- Department of Basic Medical Science, School of Medicine, Lishui University, Lishui, Zhejiang, China
| | - Xiangmin Gao
- Department of Basic Medical Science, School of Medicine, Lishui University, Lishui, Zhejiang, China
| | - Songquan Wu
- Department of Basic Medical Science, School of Medicine, Lishui University, Lishui, Zhejiang, China
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Andrew M, Jayaraman G. Production optimization and antioxidant potential of exopolysaccharide produced by a moderately halophilic bacterium Virgibacillus dokdonensis VITP14. Prep Biochem Biotechnol 2024:1-19. [PMID: 38963714 DOI: 10.1080/10826068.2024.2370879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/06/2024]
Abstract
This study aimed to enhance the extracellular polymeric substances (EPS) production of Virgibacillus dokdonensis VITP14 and explore its antioxidant potential. EPS and biomass production by VITP14 strain were studied under different culture parameters and media compositions using one factor at a time method. Among different nutrient sources, glucose and peptone were identified as suitable carbon and nitrogen sources. Furthermore, the maximum EPS production was observed at 5% of inoculum size, 5 g/L of NaCl, and 96 h of fermentation. Response surface methodology was employed to augment EPS production and investigate the optimal levels of nutrient sources with their interaction. The strain was observed to produce actual maximum EPS of about 26.4 g/L for finalized optimum medium containing glucose 20 g/L, peptone 10 g/L, and NaCl 50 g/L while the predicted maximum EPS was 26.5 g/L. There was a nine fold increase in EPS production after optimization study. Additionally, EPS has exhibited significant scavenging, reducing, and chelating potential (>85%) at their higher concentration. This study imparts valuable insights into optimizing moderately halophilic bacterial EPS production and evaluating its natural antioxidant properties. According to findings, V. dokdonensis VITP14 was a promising isolate that will provide significant benefits to biopolymer producing industries.
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Affiliation(s)
- Monic Andrew
- Department of Biotechnology, School of Biosciences and Technology, Vellore Institute of Technology, Vellore, Tamil Nadu, India
| | - Gurunathan Jayaraman
- Department of Biotechnology, School of Biosciences and Technology, Vellore Institute of Technology, Vellore, Tamil Nadu, India
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Walker RM, Sanabria VC, Youk H. Microbial life in slow and stopped lanes. Trends Microbiol 2024; 32:650-662. [PMID: 38123400 PMCID: PMC11187706 DOI: 10.1016/j.tim.2023.11.014] [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: 10/16/2023] [Revised: 11/27/2023] [Accepted: 11/28/2023] [Indexed: 12/23/2023]
Abstract
Microbes in nature often lack nutrients and face extreme or widely fluctuating temperatures, unlike microbes in growth-optimized settings in laboratories that much of the literature examines. Slowed or suspended lives are the norm for microbes. Studying them is important for understanding the consequences of climate change and for addressing fundamental questions about life: are there limits to how slowly a cell's life can progress, and how long cells can remain viable without self-replicating? Recent studies began addressing these questions with single-cell-level measurements and mathematical models. Emerging principles that govern slowed or suspended lives of cells - including lives of dormant spores and microbes at extreme temperatures - are re-defining discrete cellular states as continuums and revealing intracellular dynamics at new timescales. Nearly inactive, lifeless-appearing microbes are transforming our understanding of life.
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Affiliation(s)
- Rachel M Walker
- Department of Systems Biology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Valeria C Sanabria
- Department of Systems Biology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Hyun Youk
- Department of Systems Biology, University of Massachusetts Chan Medical School, Worcester, MA, USA.
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7
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Sharma D, Chetri PB, Ranga V, Sen S, Sarmah BK, Barooah M. Genomic analysis of acid tolerance genes and deciphering the function of ydaG gene in mitigating acid tolerance in Priestia megaterium. Front Microbiol 2024; 15:1414777. [PMID: 38966390 PMCID: PMC11222612 DOI: 10.3389/fmicb.2024.1414777] [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: 04/09/2024] [Accepted: 06/10/2024] [Indexed: 07/06/2024] Open
Abstract
Adverse environmental conditions, such as acid stress, induce bacteria to employ several strategies to overcome these stressors. These strategies include forming biofilms and activating specific molecular pathways, such as the general stress response (GSR). The genome of Priestia megaterium strain G18 was sequenced using the Illumina NextSeq 500 system, resulting in a de novo assembly of 80 scaffolds. The scaffolded genome comprises 5,367,956 bp with a GC content of 37.89%, and was compared to related strains using the MiGA web server, revealing high similarity to P. megaterium NBRC 15308 and P. aryabhattai B8W22 with ANI scores of 95.4%. Phylogenetic and ribosomal multilocus sequence typing (rMLST) analyses, based on the 16S rRNA and ribosomal protein-encoding alleles, confirmed close relationships within the P. megaterium species. Functional annotation identified 5,484 protein-coding genes, with 72.31% classified into 22 COG categories, highlighting roles in amino acid transport, transcription, carbohydrate metabolism, and ribosomal structure. An in-depth genome analysis of P. megaterium G18 revealed several key genes associated with acid tolerance. Targeted inactivation of the ydaG gene from SigB regulon, a general stress response gene, significantly reduced growth under acidic conditions compared to the wild type. qRT-PCR analysis showed increased ydaG expression in acidic conditions, further supporting its role in acid stress response. Microscopic analysis revealed no morphological differences between wild-type and mutant cells, suggesting that ydaG is not involved in maintaining cellular morphology but in facilitating acid tolerance through stress protein production. This research contributes to understanding the molecular mechanisms underlying acid tolerance in soil bacteria, P. megaterium, shedding light on potential applications in agriculture and industry.
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Affiliation(s)
- Darshana Sharma
- DBT—North East Centre for Agricultural Biotechnology, Assam Agricultural University, Jorhat, Assam, India
| | - Purna Bahadur Chetri
- DBT—North East Centre for Agricultural Biotechnology, Assam Agricultural University, Jorhat, Assam, India
| | - Vipin Ranga
- DBT—North East Centre for Agricultural Biotechnology, Assam Agricultural University, Jorhat, Assam, India
| | - Subhajit Sen
- DBT—North East Centre for Agricultural Biotechnology, Assam Agricultural University, Jorhat, Assam, India
| | - Bidyut Kumar Sarmah
- DBT—North East Centre for Agricultural Biotechnology, Assam Agricultural University, Jorhat, Assam, India
- Department of Agricultural Biotechnology, Assam Agricultural University, Jorhat, Assam, India
| | - Madhumita Barooah
- DBT—North East Centre for Agricultural Biotechnology, Assam Agricultural University, Jorhat, Assam, India
- Department of Agricultural Biotechnology, Assam Agricultural University, Jorhat, Assam, India
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8
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Cuervo L, Méndez C, Salas JA, Olano C, Malmierca MG. Volatile communication in Actinobacteria: a language for secondary metabolism regulation. Microb Cell Fact 2024; 23:181. [PMID: 38890640 PMCID: PMC11186294 DOI: 10.1186/s12934-024-02456-4] [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: 04/02/2024] [Accepted: 06/08/2024] [Indexed: 06/20/2024] Open
Abstract
BACKGROUND Volatile compounds are key elements in the interaction and communication between organisms at both interspecific and intraspecific levels. In complex bacterial communities, the emission of these fast-acting chemical messengers allows an exchange of information even at a certain distance that can cause different types of responses in the receiving organisms. The changes in secondary metabolism as a consequence of this interaction arouse great interest in the field of searching for bioactive compounds since they can be used as a tool to activate silenced metabolic pathways. Regarding the great metabolic potential that the Actinobacteria group presents in the production of compounds with attractive properties, we evaluated the reply the emitted volatile compounds can generate in other individuals of the same group. RESULTS We recently reported that volatile compounds released by different streptomycete species trigger the modulation of biosynthetic gene clusters in Streptomyces spp. which finally leads to the activation/repression of the production of secondary metabolites in the recipient strains. Here we present the application of this rationale in a broader bacterial community to evaluate volatiles as signaling effectors that drive the activation of biosynthesis of bioactive compounds in other members of the Actinobacteria group. Using cocultures of different actinobacteria (where only the volatile compounds reach the recipient strain) we were able to modify the bacterial secondary metabolism that drives overproduction (e.g., granaticins, actiphenol, chromomycins) and/or de novo production (e.g., collismycins, skyllamycins, cosmomycins) of compounds belonging to different chemical species that present important biological activities. CONCLUSIONS This work shows how the secondary metabolism of different Actinobacteria species can vary significantly when exposed in co-culture to the volatile compounds of other phylum-shared bacteria, these effects being variable depending on strains and culture media. This approach can be applied to the field of new drug discovery to increase the battery of bioactive compounds produced by bacteria that can potentially be used in treatments for humans and animals.
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Affiliation(s)
- Lorena Cuervo
- Department Functional Biology, University of Oviedo, 33006, Oviedo, Spain
- University Institute of Oncology of Asturias (I.U.O.P.A), University of Oviedo, 33006, Oviedo, Spain
- Health Research Institute of Asturias (ISPA), 33006, Oviedo, Spain
| | - Carmen Méndez
- Department Functional Biology, University of Oviedo, 33006, Oviedo, Spain
- University Institute of Oncology of Asturias (I.U.O.P.A), University of Oviedo, 33006, Oviedo, Spain
- Health Research Institute of Asturias (ISPA), 33006, Oviedo, Spain
| | - José A Salas
- Department Functional Biology, University of Oviedo, 33006, Oviedo, Spain
- University Institute of Oncology of Asturias (I.U.O.P.A), University of Oviedo, 33006, Oviedo, Spain
- Health Research Institute of Asturias (ISPA), 33006, Oviedo, Spain
| | - Carlos Olano
- Department Functional Biology, University of Oviedo, 33006, Oviedo, Spain
- University Institute of Oncology of Asturias (I.U.O.P.A), University of Oviedo, 33006, Oviedo, Spain
- Health Research Institute of Asturias (ISPA), 33006, Oviedo, Spain
| | - Mónica G Malmierca
- Department Functional Biology, University of Oviedo, 33006, Oviedo, Spain.
- University Institute of Oncology of Asturias (I.U.O.P.A), University of Oviedo, 33006, Oviedo, Spain.
- Health Research Institute of Asturias (ISPA), 33006, Oviedo, Spain.
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Sandhu AK, Fischer BR, Subramanian S, Hoppe AD, Brözel VS. Self-growth suppression in Bradyrhizobium diazoefficiens is caused by a diffusible antagonist. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.01.596975. [PMID: 38853965 PMCID: PMC11160724 DOI: 10.1101/2024.06.01.596975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Microbes in soil navigate interactions by recognizing kin, forming social groups, exhibiting antagonistic behavior, and engaging in competitive kin rivalry. Here, we investigated a novel phenomenon of self-growth suppression (sibling rivalry) observed in Bradyrhizobium diazoefficiens USDA 110. Swimming colonies of USDA 110 developed a distinct demarcation line and inter-colony zone when inoculated adjacent to each other. In addition to self, USDA 110 suppressed growth of other Bradyrhizobium strains and several other soil bacteria. We demonstrated that the phenomenon of sibling rivalry is due to growth suppression but not cell death. The cells in the inter-colony zone were culturable but have reduced respiratory activity, ATP levels and motility. The observed growth suppression was due to the presence of a diffusible effector compound. This effector was labile, preventing extraction, and identification, but it is unlikely a protein or a strong acid or base. This counterintuitive phenomenon of self-growth suppression suggests a strategic adaptation for conserving energy and resources in competitive soil environments. Bradyrhizobium's utilization of antagonism including self-growth suppression likely provides a competitive advantage for long-term success in soil ecosystems.
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Affiliation(s)
- Armaan Kaur Sandhu
- Department of Biology and Microbiology, South Dakota State University, Brookings, SD 57006
| | - Brady R. Fischer
- Department of Chemistry, Biochemistry and Physics, South Dakota State University, Brookings, SD 57006
| | - Senthil Subramanian
- Department of Biology and Microbiology, South Dakota State University, Brookings, SD 57006
| | - Adam D. Hoppe
- Department of Chemistry, Biochemistry and Physics, South Dakota State University, Brookings, SD 57006
| | - Volker S. Brözel
- Department of Biology and Microbiology, South Dakota State University, Brookings, SD 57006
- Department of Biochemistry, Genetics and Microbiology; Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, South Africa
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Nair AV, Singh A, Rajmani RS, Chakravortty D. Salmonella Typhimurium employs spermidine to exert protection against ROS-mediated cytotoxicity and rewires host polyamine metabolism to ameliorate its survival in macrophages. Redox Biol 2024; 72:103151. [PMID: 38593631 PMCID: PMC11015157 DOI: 10.1016/j.redox.2024.103151] [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: 02/12/2024] [Revised: 03/11/2024] [Accepted: 04/02/2024] [Indexed: 04/11/2024] Open
Abstract
Salmonella infection entails a cascade of attacks and defence measures. After breaching the intestinal epithelial barrier, Salmonella is phagocytosed by macrophages, where the bacteria encounter multiple stresses, to which it employs relevant countermeasures. Our study shows that, in Salmonella, the polyamine spermidine activates a stress response mechanism by regulating critical antioxidant genes. Salmonella Typhimurium mutants for spermidine transport and synthesis cannot mount an antioxidative response, resulting in high intracellular ROS levels. These mutants are also compromised in their ability to be phagocytosed by macrophages. Furthermore, it regulates a novel enzyme in Salmonella, Glutathionyl-spermidine synthetase (GspSA), which prevents the oxidation of proteins in E. coli. Moreover, the spermidine mutants and the GspSA mutant show significantly reduced survival in the presence of hydrogen peroxide in vitro and reduced organ burden in the mouse model of Salmonella infection. Conversely, in macrophages isolated from gp91phox-/- mice, we observed a rescue in the attenuated fold proliferation previously observed upon infection. We found that Salmonella upregulates polyamine biosynthesis in the host through its effectors from SPI-1 and SPI-2, which addresses the attenuated proliferation observed in spermidine transport mutants. Thus, inhibition of this pathway in the host abrogates the proliferation of Salmonella Typhimurium in macrophages. From a therapeutic perspective, inhibiting host polyamine biosynthesis using an FDA-approved chemopreventive drug, D, L-α-difluoromethylornithine (DFMO), reduces Salmonella colonisation and tissue damage in the mouse model of infection while enhancing the survival of infected mice. Therefore, our work provides a mechanistic insight into the critical role of spermidine in stress resistance of Salmonella. It also reveals a bacterial strategy in modulating host metabolism to promote their intracellular survival and shows the potential of DFMO to curb Salmonella infection.
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Affiliation(s)
- Abhilash Vijay Nair
- Department of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bengaluru, India
| | - Anmol Singh
- Department of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bengaluru, India
| | - R S Rajmani
- Molecular Biophysics Unit, Indian Institute of Science, Bengaluru, India
| | - Dipshikha Chakravortty
- Department of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bengaluru, India; Adjunct Faculty, School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, India.
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Zhu M, Dai X. Shaping of microbial phenotypes by trade-offs. Nat Commun 2024; 15:4238. [PMID: 38762599 PMCID: PMC11102524 DOI: 10.1038/s41467-024-48591-9] [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: 02/06/2024] [Accepted: 05/06/2024] [Indexed: 05/20/2024] Open
Abstract
Growth rate maximization is an important fitness strategy for microbes. However, the wide distribution of slow-growing oligotrophic microbes in ecosystems suggests that rapid growth is often not favored across ecological environments. In many circumstances, there exist trade-offs between growth and other important traits (e.g., adaptability and survival) due to physiological and proteome constraints. Investments on alternative traits could compromise growth rate and microbes need to adopt bet-hedging strategies to improve fitness in fluctuating environments. Here we review the mechanistic role of trade-offs in controlling bacterial growth and further highlight its ecological implications in driving the emergences of many important ecological phenomena such as co-existence, population heterogeneity and oligotrophic/copiotrophic lifestyles.
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Affiliation(s)
- Manlu Zhu
- State Key Laboratory of Green Pesticide, School of Life Sciences, Central China Normal University, Wuhan, PR China
| | - Xiongfeng Dai
- State Key Laboratory of Green Pesticide, School of Life Sciences, Central China Normal University, Wuhan, PR China.
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12
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Rajput SN, Naeem BK, Ali A, Salim A, Khan I. Expansion of human umbilical cord derived mesenchymal stem cells in regenerative medicine. World J Stem Cells 2024; 16:410-433. [PMID: 38690517 PMCID: PMC11056638 DOI: 10.4252/wjsc.v16.i4.410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 02/01/2024] [Accepted: 03/18/2024] [Indexed: 04/25/2024] Open
Abstract
BACKGROUND Stem cells are undifferentiated cells that possess the potential for self-renewal with the capacity to differentiate into multiple lineages. In humans, their limited numbers pose a challenge in fulfilling the necessary demands for the regeneration and repair of damaged tissues or organs. Studies suggested that mesenchymal stem cells (MSCs), necessary for repair and regeneration via transplantation, require doses ranging from 10 to 400 million cells. Furthermore, the limited expansion of MSCs restricts their therapeutic application. AIM To optimize a novel protocol to achieve qualitative and quantitative expansion of MSCs to reach the targeted number of cells for cellular transplantation and minimize the limitations in stem cell therapy protocols. METHODS Human umbilical cord (hUC) tissue derived MSCs were obtained and re-cultured. These cultured cells were subjected to the following evaluation procedures: Immunophenotyping, immunocytochemical staining, trilineage differentiation, population doubling time and number, gene expression markers for proliferation, cell cycle progression, senescence-associated β-galactosidase assay, human telomerase reverse transcriptase (hTERT) expression, mycoplasma, cytomegalovirus and endotoxin detection. RESULTS Analysis of pluripotent gene markers Oct4, Sox2, and Nanog in recultured hUC-MSC revealed no significant differences. The immunophenotypic markers CD90, CD73, CD105, CD44, vimentin, CD29, Stro-1, and Lin28 were positively expressed by these recultured expanded MSCs, and were found negative for CD34, CD11b, CD19, CD45, and HLA-DR. The recultured hUC-MSC population continued to expand through passage 15. Proliferative gene expression of Pax6, BMP2, and TGFb1 showed no significant variation between recultured hUC-MSC groups. Nevertheless, a significant increase (P < 0.001) in the mitotic phase of the cell cycle was observed in recultured hUC-MSCs. Cellular senescence markers (hTERT expression and β-galactosidase activity) did not show any negative effect on recultured hUC-MSCs. Additionally, quality control assessments consistently confirmed the absence of mycoplasma, cytomegalovirus, and endotoxin contamination. CONCLUSION This study proposes the development of a novel protocol for efficiently expanding stem cell population. This would address the growing demand for larger stem cell doses needed for cellular transplantation and will significantly improve the feasibility of stem cell based therapies.
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Affiliation(s)
- Shafiqa Naeem Rajput
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Sindh, Pakistan
| | - Bushra Kiran Naeem
- Surgical Unit 4, Dr. Ruth KM Pfau Civil Hospital, Karachi 74400, Pakistan
| | - Anwar Ali
- Department of Physiology, University of Karachi, Karachi 75270, Pakistan
| | - Asmat Salim
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Sindh, Pakistan
| | - Irfan Khan
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Sindh, Pakistan
- Center for Regenerative Medicine and Stem Cells Research, and Department of Ophthalmology and Visual Sciences, The Aga Khan University, Karachi 74800, Sindh, Pakistan.
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13
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Wang YC, Lv YH, Hu XR, Lin YT, Crittenden JC, Wang C. Microbial metabolic flexibility guarantees function resilience in response to starvation disturbance. BIORESOURCE TECHNOLOGY 2024; 393:130137. [PMID: 38040311 DOI: 10.1016/j.biortech.2023.130137] [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: 10/03/2023] [Revised: 11/20/2023] [Accepted: 11/28/2023] [Indexed: 12/03/2023]
Abstract
Starvation disturbance due to nutrient limitation is a common problem in bioreactors. However, an understanding of how microbial systems respond to starvation remains in its infancy. Here the metabolic response mechanism of a biofilm community to starvation was investigated using a well-controlled gaseous toluene treatment biofilter through interruption of its operation. It was found that metabolic characteristics showed significant differences before and after starvation. The dominant carbon source utilization type shifted from amino acids and carboxylic acids to esters and carbohydrates after starvation, which is more conducive to improving energy production. Metagenomic sequencing analysis supported that the changes in the dominant metabolic substrate, enhanced metabolic stability, and flexibility in the mode of energy metabolism could be the main ways to guarantee functional resilience in ecosystems after starvation. The results highlight the microbial metabolic response to starvation, which would be beneficial to the understanding of functional resilience and bioreactor stability.
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Affiliation(s)
- Yong-Chao Wang
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China; Tianjin Key Lab of Indoor Air Environmental Quality Control, Tianjin 300072, China
| | - Ya-Hui Lv
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China; Tianjin Key Lab of Indoor Air Environmental Quality Control, Tianjin 300072, China
| | - Xu-Rui Hu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China; Tianjin Key Lab of Indoor Air Environmental Quality Control, Tianjin 300072, China
| | - Yu-Ting Lin
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China; Tianjin Key Lab of Indoor Air Environmental Quality Control, Tianjin 300072, China
| | - John C Crittenden
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, United States
| | - Can Wang
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China; Tianjin Key Lab of Indoor Air Environmental Quality Control, Tianjin 300072, China.
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14
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McDonald MD, Owusu-Ansah C, Ellenbogen JB, Malone ZD, Ricketts MP, Frolking SE, Ernakovich JG, Ibba M, Bagby SC, Weissman JL. What is microbial dormancy? Trends Microbiol 2024; 32:142-150. [PMID: 37689487 DOI: 10.1016/j.tim.2023.08.006] [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: 03/10/2023] [Revised: 08/14/2023] [Accepted: 08/15/2023] [Indexed: 09/11/2023]
Abstract
Life can be stressful. One way to deal with stress is to simply wait it out. Microbes do this by entering a state of reduced activity and increased resistance commonly called 'dormancy'. But what is dormancy? Different scientific disciplines emphasize distinct traits and phenotypic ranges in defining dormancy for their microbial species and system-specific questions of interest. Here, we propose a unified definition of microbial dormancy, using a broad framework to place earlier discipline-specific definitions in a new context. We then discuss how this new definition and framework may improve our ability to investigate dormancy using multi-omics tools. Finally, we leverage our framework to discuss the diversity of genomic mechanisms for dormancy in an extreme environment that challenges easy definitions - the permafrost.
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Affiliation(s)
- Mark D McDonald
- Argonne National Laboratory, Environmental Sciences Division, Lemont, IL 60439, USA
| | | | - Jared B Ellenbogen
- EMergent Ecosystem Response to ChanGE (EMERGE) Biology Integration Institute, Ohio State University, Columbus, OH 43210, USA; Colorado State University, Department of Soil and Crop Sciences, Fort Collins, CO 80523, USA
| | - Zachary D Malone
- University of California, Merced Environmental Systems Graduate Group, Merced, CA 95343, USA
| | - Michael P Ricketts
- Argonne National Laboratory, Environmental Sciences Division, Lemont, IL 60439, USA
| | - Steve E Frolking
- EMergent Ecosystem Response to ChanGE (EMERGE) Biology Integration Institute, Ohio State University, Columbus, OH 43210, USA; University of New Hampshire, Institute for the Study of Earth, Oceans, and Space, Durham, NH 03824, USA
| | - Jessica Gilman Ernakovich
- EMergent Ecosystem Response to ChanGE (EMERGE) Biology Integration Institute, Ohio State University, Columbus, OH 43210, USA; University of New Hampshire, Natural Resources and the Environment, Durham, NH 03824, USA
| | - Michael Ibba
- EMergent Ecosystem Response to ChanGE (EMERGE) Biology Integration Institute, Ohio State University, Columbus, OH 43210, USA; Chapman University, Schmid College of Science and Technology, Orange, CA 92866, USA
| | - Sarah C Bagby
- EMergent Ecosystem Response to ChanGE (EMERGE) Biology Integration Institute, Ohio State University, Columbus, OH 43210, USA; Case Western Reserve University, Department of Biology, Cleveland, OH 44106, USA
| | - J L Weissman
- Chapman University, Schmid College of Science and Technology, Orange, CA 92866, USA; University of Southern California, Department of Biological Sciences, Los Angeles, CA 90007, USA.
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15
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Zhong M, Li Y, Deng L, Fang J, Yu X. Insight into the adaptation mechanisms of high hydrostatic pressure in physiology and metabolism of hadal fungi from the deepest ocean sediment. mSystems 2024; 9:e0108523. [PMID: 38117068 PMCID: PMC10804941 DOI: 10.1128/msystems.01085-23] [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: 10/17/2023] [Accepted: 11/14/2023] [Indexed: 12/21/2023] Open
Abstract
High hydrostatic pressure (HHP) influences the life processes of organisms living at depth in the oceans. While filamentous fungi are one of the essential members of deep-sea microorganisms, few works have explored their piezotolerance to HHP. Here, we obtained three homogeneous Aspergillus sydowii from terrestrial, shallow, and hadal areas, respectively, to compare their pressure resistance. A set of all-around evaluation methods including determination of growth rate, metabolic activity, and microscopic staining observation was established and indicated that A. sydowii DM1 from the hadal area displayed significant piezotolerance. Global analysis of transcriptome data under elevated HHP revealed that A. sydowii DM1 proactively modulated cell membrane permeability, hyphae morphology, and septal quantities for seeking a better livelihood under mild pressure. Besides, differentially expressed genes were mainly enriched in the biosynthesis of amino acids, carbohydrate metabolism, cell process, etc., implying how the filamentous fungi respond to elevated pressure at the molecular level. We speculated that A. sydowii DM1 could acclimatize itself to HHP by adopting several strategies, including environmental response pathway HOG-MAPK, stress proteins, and cellular metabolisms.IMPORTANCEFungi play an ecological and biological function in marine environments, while the physiology of filamentous fungi under high hydrostatic pressure (HHP) is an unknown territory due to current technologies. As filamentous fungi are found in various niches, Aspergillus sp. from deep-sea inspire us to the physiological trait of eukaryotes under HHP, which can be considered as a prospective research model. Here, the evaluation methods we constructed would be universal for most filamentous fungi to assess their pressure resistance, and we found that Aspergillus sydowii DM1 from the hadal area owned better piezotolerance and the active metabolisms under HHP indicated the existence of undiscovered metabolic strategies for hadal fungi. Since pressure-related research of marine fungi has been unexpectedly neglected, our study provided an enlightening strategy for them under HHP; we believed that understanding their adaptation and ecological function in original niches will be accelerated in the perceivable future.
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Affiliation(s)
- Maosheng Zhong
- Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai, China
| | - Yongqi Li
- Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai, China
| | - Ludan Deng
- Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai, China
| | - Jiasong Fang
- Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai, China
| | - Xi Yu
- Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai, China
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16
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Liang S, Zhang W, Grossart HP, Gadd GM, Liu W, Yang Y. The unique climate shapes distinct life-history traits of abundant bacteria in Tibetan Plateau grassland soil. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 908:168353. [PMID: 37935266 DOI: 10.1016/j.scitotenv.2023.168353] [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: 08/05/2023] [Revised: 11/02/2023] [Accepted: 11/03/2023] [Indexed: 11/09/2023]
Abstract
The unique geographical patterns of the Qinghai-Tibet Plateau have shaped the different climatic characteristics of the Lhasa and Nyang River watersheds. However, our understanding of climate-dependent life history strategies in riparian grasslands is very limited. In this research, we have compared the causes and consequences of variations in the composition of soil abundant and rare bacterial taxa in the Nyang and Lhasa River watersheds. The results showed that the abundant bacteria, rather than the rare bacteria, exhibited distinct life history strategies between the Lhasa and Nyang watersheds that were a consequence of climate patterns. The wetter climate of the Nyang watershed led to a high ratio of r-strategists among the abundant bacteria (Abundant K:r = 0.323), while in the less favourable climate of the Lhasa watershed, K-strategists were more common among the soil abundant bacteria (Abundant K:r = 0.542). The assembly processes of abundant and rare bacteria in the Lhasa region under relatively harsh climatic conditions seemed to be more affected by variable selection than those in the Nyang region. Moreover, abundant bacteria in the Lhasa region developed stronger potentially cooperative relationships and exhibited a stronger metabolic capacity than those in the Nyang region. The 26 different functional genes identified in LS were highly associated with 38 abundant bacterial species. In contrast, the 16 identified functional genes in NY were highly correlated with 16 abundant bacterial species. These results provide new insights into climate-dependent life history strategies of soil bacterial communities with different abundances in riparian grasslands of the Tibetan Plateau. Contrasting the life history strategies of bacterial taxa with different abundances contributes to a better mechanistic knowledge of their impact on ecosystem functioning under current and future effects of global climate change.
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Affiliation(s)
- Shuxin Liang
- School of Ecology and Environment, Tibet University, Lhasa 850000, China; Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China
| | - Weihong Zhang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China; University of Chinese Academy of Sciences, Beijing 100049, China; Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan 430074, China
| | - Hans-Peter Grossart
- Leibniz-Institute for Freshwater Ecology and Inland Fisheries (IGB), Neuglobsow 16775, Germany; Institute for Biochemistry and Biology, Potsdam University, Potsdam 14469, Germany
| | - Geoffrey Michael Gadd
- Geomicrobiology Group, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, UK; State Key Laboratory of Heavy Oil Processing, State Key Laboratory of Petroleum Pollution Control, China University of Petroleum, Beijing 102249, China
| | - Wenzhi Liu
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China; University of Chinese Academy of Sciences, Beijing 100049, China; Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan 430074, China.
| | - Yuyi Yang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China; University of Chinese Academy of Sciences, Beijing 100049, China; Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan 430074, China.
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17
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Marton HL, Bhatt A, Sagona AP, Kilbride P, Gibson MI. Screening of Hydrophilic Polymers Reveals Broad Activity in Protecting Phages during Cryopreservation. Biomacromolecules 2024; 25:413-424. [PMID: 38124388 PMCID: PMC10777348 DOI: 10.1021/acs.biomac.3c01042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 12/01/2023] [Accepted: 12/01/2023] [Indexed: 12/23/2023]
Abstract
Bacteriophages have many biotechnological and therapeutic applications, but as with other biologics, cryopreservation is essential for storage and distribution. Macromolecular cryoprotectants are emerging for a range of biologics, but the chemical space for polymer-mediated phage cryopreservation has not been explored. Here we screen the cryoprotective effect of a panel of polymers against five distinct phages, showing that nearly all the tested polymers provide a benefit. Exceptions were poly(methacrylic acid) and poly(acrylic acid), which can inhibit phage-infection with bacteria, making post-thaw recovery challenging to assess. A particular benefit of a polymeric cryopreservation formulation is that the polymers do not function as carbon sources for the phage hosts (bacteria) and hence do not interfere with post-thaw measurements. This work shows that phages are amenable to protection with hydrophilic polymers and opens up new opportunities for advanced formulations for future phage therapies and to take advantage of the additional functionality brought by the polymers.
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Affiliation(s)
- Huba L. Marton
- Department
of Chemistry, University of Warwick, Coventry, CV4 7AL, United Kingdom
| | - Apoorva Bhatt
- School
of Biosciences, University of Birmingham, Birmingham, B15 2TT, United Kingdom
- Institute
of Microbiology and Infection, University
of Birmingham, Birmingham, B15 2TT, United
Kingdom
| | - Antonia P. Sagona
- School
of Life Sciences, University of Warwick, Coventry, CV4 7AL, United Kingdom
| | - Peter Kilbride
- Asymptote,
Cytiva, Chivers Way, Cambridge CB24 9BZ, United Kingdom
| | - Matthew I. Gibson
- Department
of Chemistry, University of Warwick, Coventry, CV4 7AL, United Kingdom
- Warwick
Medical School, University of Warwick, Coventry, CV4 7AL, United Kingdom
- Department
of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
- Manchester
Institute of Biotechnology, University of
Manchester, 131 Princess
Street, Manchester, M1
7DN, United Kingdom
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18
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Valencia-Marin MF, Chávez-Avila S, Guzmán-Guzmán P, Orozco-Mosqueda MDC, de Los Santos-Villalobos S, Glick BR, Santoyo G. Survival strategies of Bacillus spp. in saline soils: Key factors to promote plant growth and health. Biotechnol Adv 2024; 70:108303. [PMID: 38128850 DOI: 10.1016/j.biotechadv.2023.108303] [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: 08/16/2023] [Revised: 11/16/2023] [Accepted: 12/12/2023] [Indexed: 12/23/2023]
Abstract
Soil salinity is one of the most important abiotic factors that affects agricultural production worldwide. Because of saline stress, plants face physiological changes that have negative impacts on the various stages of their development, so the employment of plant growth-promoting bacteria (PGPB) is one effective means to reduce such toxic effects. Bacteria of the Bacillus genus are excellent PGPB and have been extensively studied, but what traits makes them so extraordinary to adapt and survive under harsh situations? In this work we review the Bacillus' innate abilities to survive in saline stressful soils, such as the production osmoprotectant compounds, antioxidant enzymes, exopolysaccharides, and the modification of their membrane lipids. Other survival abilities are also discussed, such as sporulation or a reduced growth state under the scope of a functional interaction in the rhizosphere. Thus, the most recent evidence shows that these saline adaptive activities are important in plant-associated bacteria to potentially protect, direct and indirect plant growth-stimulating activities. Additionally, recent advances on the mechanisms used by Bacillus spp. to improve the growth of plants under saline stress are addressed, including genomic and transcriptomic explorations. Finally, characterization and selection of Bacillus strains with efficient survival strategies are key factors in ameliorating saline problems in agricultural production.
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Affiliation(s)
- María F Valencia-Marin
- Instituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Mich. 58030, Mexico
| | - Salvador Chávez-Avila
- Instituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Mich. 58030, Mexico
| | - Paulina Guzmán-Guzmán
- Instituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Mich. 58030, Mexico
| | - Ma Del Carmen Orozco-Mosqueda
- Departamento de Ingeniería Bioquímica y Ambiental, Tecnológico Nacional de México en Celaya, 38010 Celaya, Gto, Mexico
| | | | - Bernard R Glick
- Department of Biology, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | - Gustavo Santoyo
- Instituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Mich. 58030, Mexico.
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19
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Godfrey B, Li B, Gottshall E, Brysons S, Abrahamson B, Winkler M. Co-immobilization of AOA strains with anammox bacteria in three different synthetic bio-granules maintained under two substrate-level conditions. CHEMOSPHERE 2023; 342:140192. [PMID: 37722534 DOI: 10.1016/j.chemosphere.2023.140192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 08/28/2023] [Accepted: 09/14/2023] [Indexed: 09/20/2023]
Abstract
Hydrogel encapsulation of ammonium oxidizing archaea (AOA) along with anammox bacteria holds potential to enable mainstream partial nitritation (PN)-anammox process attributing to AOA's high affinity to ammonia and oxygen. This study explored the growth of AOA and anammox in hydrogel-based synthetic biogranules by testing two AOA strains, three types of hydrogel beads and two substrate levels, to identify the optimal combination favoring the concomitant growth of AOA and anammox. The AOA Nitrososphaera viennensis (AOA-NV) exhibited higher abundance (10-2.3±0.6 AOA/16S) than the AOA-DW (10-4.7±0.8 AOA/16S) during the entire experimental period. Amongst the three types of hydrogel beads, the PVA-SA-BaCl2 (140 days) and PVA-SA-H3BO3 beads (>180 days) exhibited better long-term structural stability than the PEGDMA-SA-CaCl2 beads. The PVA-SA-H3BO3 beads exhibited the best long-term stability and both the PVA/SA BaCl2 and PVA-SA-H3BO3 beads had comparable ability to retain AOA, anammox and the overall microbial community. Substrate conditions rather than the bead type primarily controlled the microbial community structure. Modest substrate concentrations (1 mM NH4+-N in the feed and 0.8 mg/L dissolved oxygen (DO) in the reactor during aeration phase) followed by low substrate conditions (0.1 mM NH4+-N and 0.2 mg DO/L) both supported the growth of AOA and anammox, while the low substrate condition also suppressed the growth of ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB), with AOA /AOB and anammox/NOB ratio of 0.7 and 0.4 at moderate substrate condition and 16.5 and 2.6 at low substrate condition.
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Affiliation(s)
- Bruce Godfrey
- University of Washington, Department of Civil & Environmental Engineering, Seattle, WA, 98195, USA
| | - Bo Li
- University of Washington, Department of Civil & Environmental Engineering, Seattle, WA, 98195, USA.
| | - Ekaterina Gottshall
- University of Washington, Department of Civil & Environmental Engineering, Seattle, WA, 98195, USA
| | - Samuel Brysons
- University of Washington, Department of Civil & Environmental Engineering, Seattle, WA, 98195, USA
| | - Britt Abrahamson
- University of Washington, Department of Civil & Environmental Engineering, Seattle, WA, 98195, USA
| | - Mari Winkler
- University of Washington, Department of Civil & Environmental Engineering, Seattle, WA, 98195, USA
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20
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Liu B, Garza DR, Gonze D, Krzynowek A, Simoens K, Bernaerts K, Geirnaert A, Faust K. Starvation responses impact interaction dynamics of human gut bacteria Bacteroides thetaiotaomicron and Roseburia intestinalis. THE ISME JOURNAL 2023; 17:1940-1952. [PMID: 37670028 PMCID: PMC10579405 DOI: 10.1038/s41396-023-01501-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 08/21/2023] [Accepted: 08/23/2023] [Indexed: 09/07/2023]
Abstract
Bacterial growth often alters the environment, which in turn can impact interspecies interactions among bacteria. Here, we used an in vitro batch system containing mucin beads to emulate the dynamic host environment and to study its impact on the interactions between two abundant and prevalent human gut bacteria, the primary fermenter Bacteroides thetaiotaomicron and the butyrate producer Roseburia intestinalis. By combining machine learning and flow cytometry, we found that the number of viable B. thetaiotaomicron cells decreases with glucose consumption due to acid production, while R. intestinalis survives post-glucose depletion by entering a slow growth mode. Both species attach to mucin beads, but only viable cell counts of B. thetaiotaomicron increase significantly. The number of viable co-culture cells varies significantly over time compared to those of monocultures. A combination of targeted metabolomics and RNA-seq showed that the slow growth mode of R. intestinalis represents a diauxic shift towards acetate and lactate consumption, whereas B. thetaiotaomicron survives glucose depletion and low pH by foraging on mucin sugars. In addition, most of the mucin monosaccharides we tested inhibited the growth of R. intestinalis but not B. thetaiotaomicron. We encoded these causal relationships in a kinetic model, which reproduced the observed dynamics. In summary, we explored how R. intestinalis and B. thetaiotaomicron respond to nutrient scarcity and how this affects their dynamics. We highlight the importance of understanding bacterial metabolic strategies to effectively modulate microbial dynamics in changing conditions.
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Affiliation(s)
- Bin Liu
- Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, Laboratory of Molecular Bacteriology, KU Leuven, B-3000, Leuven, Belgium
| | - Daniel Rios Garza
- Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, Laboratory of Molecular Bacteriology, KU Leuven, B-3000, Leuven, Belgium
| | - Didier Gonze
- Unité de Chronobiologie Théorique, Faculté des Sciences, CP 231, Université Libre de Bruxelles, Bvd du Triomphe, B-1050, Bruxelles, Belgium
| | - Anna Krzynowek
- Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, Laboratory of Molecular Bacteriology, KU Leuven, B-3000, Leuven, Belgium
| | - Kenneth Simoens
- Department of Chemical Engineering, Chemical and Biochemical Reactor Engineering and Safety (CREaS), KU Leuven, B-3001, Leuven, Belgium
| | - Kristel Bernaerts
- Department of Chemical Engineering, Chemical and Biochemical Reactor Engineering and Safety (CREaS), KU Leuven, B-3001, Leuven, Belgium
| | - Annelies Geirnaert
- Laboratory of Food Biotechnology, Department of Health Sciences and Technology, Institute of Food, Nutrition and Health, ETH Zürich, CH-8092, Zürich, Switzerland
| | - Karoline Faust
- Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, Laboratory of Molecular Bacteriology, KU Leuven, B-3000, Leuven, Belgium.
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21
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Sun J, Feng Y, Zheng R, Kong L, Wu X, Zhang K, Zhou J, Liu S. Chameleon-like Anammox Bacteria for Surface Color Change after Suffering Starvation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:15087-15098. [PMID: 37754765 DOI: 10.1021/acs.est.3c04000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/28/2023]
Abstract
Bacteria are often exposed to long-term starvation during transportation and storage, during which a series of enzymes and metabolic pathways are activated to ensure survival. However, why the surface color of the bacteria changes during starvation is still not well-known. In this study, we found black anammox consortia suffering from long-term starvation contained 0.86 mmol gVSS-1 cytochrome c, which had no significant discrepancy compared with the red anammox consortia (P > 0.05), indicating cytochrome c was not the key issue for chromaticity change. Conversely, we found that under starvation conditions cysteine degradation is an important metabolic pathway for the blackening of the anammox consortia for H2S production. In particular, anammox bacteria contain large amounts of iron-rich nanoparticles, cytochrome c, and other iron-sulfur clusters that are converted to produce free iron. H2S combines with free iron in bacteria to form Fe-S compounds, which eventually exist stably as FeS2, mainly in the extracellular space. Interestingly, FeS2 could be oxidized by air aeration, which makes the consortia turn red again. The unique self-protection mechanism makes the whole consortia appear black, avoiding inhibition by high concentrations of H2S and achieving Fe storage. This study expands the understanding of the metabolites of anammox bacteria as well as the bacterial survival mechanism during starvation.
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Affiliation(s)
- Jingqi Sun
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Beijing 100871, China
| | - Yiming Feng
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Beijing 100871, China
| | - Ru Zheng
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Beijing 100871, China
| | - Lingrui Kong
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Beijing 100871, China
| | - Xiaogang Wu
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Beijing 100871, China
| | - Kuo Zhang
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Beijing 100871, China
| | - Jianhang Zhou
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Beijing 100871, China
| | - Sitong Liu
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Beijing 100871, China
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22
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Wood E, Schulenburg H, Rosenstiel P, Bergmiller T, Ankrett D, Gudelj I, Beardmore R. Ribosome-binding antibiotics increase bacterial longevity and growth efficiency. Proc Natl Acad Sci U S A 2023; 120:e2221507120. [PMID: 37751555 PMCID: PMC10556576 DOI: 10.1073/pnas.2221507120] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 07/11/2023] [Indexed: 09/28/2023] Open
Abstract
Antibiotics, by definition, reduce bacterial growth rates in optimal culture conditions; however, the real-world environments bacteria inhabit see rapid growth punctuated by periods of low nutrient availability. How antibiotics mediate population decline during these periods is poorly understood. Bacteria cannot optimize for all environmental conditions because a growth-longevity tradeoff predicts faster growth results in faster population decline, and since bacteriostatic antibiotics slow growth, they should also mediate longevity. We quantify how antibiotics, their targets, and resistance mechanisms influence longevity using populations of Escherichia coli and, as the tradeoff predicts, populations are maintained for longer if they encounter ribosome-binding antibiotics doxycycline and erythromycin, a finding that is not observed using antibiotics with alternative cellular targets. This tradeoff also predicts resistance mechanisms that increase growth rates during antibiotic treatment could be detrimental during nutrient stresses, and indeed, we find resistance by ribosomal protection removes benefits to longevity provided by doxycycline. We therefore liken ribosomal protection to a "Trojan horse" because it provides protection from an antibiotic but, during nutrient stresses, it promotes the demise of the bacteria. Seeking mechanisms to support these observations, we show doxycycline promotes efficient metabolism and reduces the concentration of reactive oxygen species. Seeking generality, we sought another mechanism that affects longevity and we found the number of doxycycline targets, namely, the ribosomal RNA operons, mediates growth and longevity even without antibiotics. We conclude that slow growth, as observed during antibiotic treatment, can help bacteria overcome later periods of nutrient stress.
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Affiliation(s)
- Emily Wood
- Biosciences, College of Life and Environmental Sciences, University of Exeter, ExeterEX4 4QD, United Kingdom
- Engineering and Physical Sciences Research Council Hub for Quantitative Modelling in Healthcare, University of Exeter, ExeterEX4 4QJ, United Kingdom
| | - Hinrich Schulenburg
- Evolutionary Ecology and Genetics, Zoologisches Institut, Christian-Albrechts-Universität zu Kiel, Am Botanischen Garten 1-9, Kiel24118, Germany
| | - Philip Rosenstiel
- Instituts für Klinische Molekularbiologie, Dekanat der Medizinischen Fakultät, Christian-Albrechts-Universität zu Kiel, Christian-Albrechts-Platz 4, KielD-24118, Germany
| | - Tobias Bergmiller
- Biosciences, College of Life and Environmental Sciences, University of Exeter, ExeterEX4 4QD, United Kingdom
| | - Dyan Ankrett
- Biosciences, College of Life and Environmental Sciences, University of Exeter, ExeterEX4 4QD, United Kingdom
| | - Ivana Gudelj
- Biosciences, College of Life and Environmental Sciences, University of Exeter, ExeterEX4 4QD, United Kingdom
| | - Robert Beardmore
- Biosciences, College of Life and Environmental Sciences, University of Exeter, ExeterEX4 4QD, United Kingdom
- Engineering and Physical Sciences Research Council Hub for Quantitative Modelling in Healthcare, University of Exeter, ExeterEX4 4QJ, United Kingdom
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23
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Lin Z, Wang G, Zhang K, Jiang S, Li S, Yang H. Metabolomics investigation of global responses of Cronobacter sakazakii against common sanitizing in infant formula processing environments. Food Res Int 2023; 172:113162. [PMID: 37689917 DOI: 10.1016/j.foodres.2023.113162] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 06/14/2023] [Accepted: 06/16/2023] [Indexed: 09/11/2023]
Abstract
Cronobacter sakazakii, an opportunistic bacterium, has raised a serious outbreak in powdered infant formula recent years. In this work, four sanitizing strategies used during infant formula processing, including chlorine, quaternary ammonium chloride (QAC), 60 °C heating, and malic acid (MA), were utilized against C. sakazakii among planktonic, air-dried (A), and air-dried & washed (AW) state, followed by an exploration of the metabolic responses induced by these treatments via a dual-platform metabolomics analysis with the ultra-high performance liquid chromatography-mass spectrometry and nuclear magnetic resonance. In the planktonic state, MA was the most effective in inhibiting bacterial growth, followed by chlorine, QAC, and 60 °C heating. Under A state, the efficacy of heating improved considerably, compared to that in the planktonic state, and remained unaltered under AW state. Chlorine and QAC were ineffective to control bacterial growth under A state, but their efficacy rose under AW state. Furthermore, the metabolomic analysis revealed chlorine induces amino acids catabolism, membrane lysis, and depression in carbohydrate and nucleotide metabolism in both planktonic and AW states, while the initiation of antioxidation mechanism was only found under AW state. Although the metabolic change caused by QAC in the planktonic state was similar to chlorine, the accumulation of osmoprotectant and membrane phospholipids within the AW cells reflected the effort to restore intracellular homeostasis upon QAC. Heating was characterized by considerable amino acid anabolism, along with mildly perturbed carbohydrate and nucleotide metabolism for heat shock protein preparation in both states. Lastly, MA promoted amino acid-dependent acid resistance under the planktonic state, and the regulation of antioxidation and osmoprotection under AW state. The metabolomics study elucidated the intracellular perturbation induced by common sanitizing, as well as the bacterial response, which provides insights for novel sanitization development.
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Affiliation(s)
- Zejia Lin
- Department of Food Science & Technology, National University of Singapore, Singapore 117542, Singapore.
| | - Guoshu Wang
- Department of Food Science & Technology, National University of Singapore, Singapore 117542, Singapore
| | - Kexin Zhang
- Department of Food Science & Technology, National University of Singapore, Singapore 117542, Singapore
| | - Shaoqian Jiang
- Department of Food Science & Technology, National University of Singapore, Singapore 117542, Singapore
| | - Songshen Li
- Department of Food Science & Technology, National University of Singapore, Singapore 117542, Singapore
| | - Hongshun Yang
- Shaoxing Key Laboratory of Traditional Fermentation Food and Human Health, Jiangnan University (Shaoxing) Industrial Technology Research Institute, Zhejiang 312000, China
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24
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Chen L, Wang C, Su J. Understanding the Effect of Different Glucose Concentrations in the Oligotrophic Bacterium Bacillus subtilis BS-G1 through Transcriptomics Analysis. Microorganisms 2023; 11:2401. [PMID: 37894061 PMCID: PMC10609351 DOI: 10.3390/microorganisms11102401] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Revised: 09/16/2023] [Accepted: 09/22/2023] [Indexed: 10/29/2023] Open
Abstract
Glucose is an important carbon source for microbial growth, and its content in infertile soils is essential for the growth of bacteria. Since the mechanism of oligotrophic bacterium adaptation in barren soils is unclear, this research employed RNA-seq technology to examine the impact of glucose concentration on the oligotrophic bacterium B. subtilis BS-G1 in soil affected by desertification. A global transcriptome analysis (RNA-Seq) revealed that the significantly differentially expressed genes (DEGs) histidine metabolism, glutamate synthesis, the HIF-1 signaling pathway, sporulation, and the TCA cycle pathway of B. subtilis BS-G1 were significantly enriched with a 0.015 g/L glucose concentration (L group), compared to a 10 g/L glucose concentration (H group). The DEGs amino acid system, two-component system, metal ion transport, and nitrogen metabolism system of B. subtilis BS-G1 were significantly enriched in the 5 g/L glucose concentration (M group), compared with the H group. In addition, the present study identified the regulation pattern and key genes under a low-glucose environment (7 mRNAs and 16 sRNAs). This study primarily investigates the variances in the regulatory pathways of the oligotrophic B. subtilis BS-G1, which holds substantial importance in comprehending the mechanism underlying the limited sugar tolerance of oligotrophic bacteria.
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Affiliation(s)
- Liping Chen
- Key Laboratory of Ministry of Education for Protection and Utilization of Special Biological Resources, School of Life Sciences, Ningxia University, Yinchuan 750021, China
| | - Chenglong Wang
- Key Laboratory of Ministry of Education for Protection and Utilization of Special Biological Resources, School of Life Sciences, Ningxia University, Yinchuan 750021, China
| | - Jianyu Su
- Key Laboratory of Ministry of Education for Protection and Utilization of Special Biological Resources, School of Life Sciences, Ningxia University, Yinchuan 750021, China
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25
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Gattinger D, Pichler K, Weil T, Sattler B. A comparative approach to confirm antibiotic-resistant microbes in the cryosphere. Front Microbiol 2023; 14:1212378. [PMID: 37601352 PMCID: PMC10435281 DOI: 10.3389/fmicb.2023.1212378] [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: 04/26/2023] [Accepted: 07/12/2023] [Indexed: 08/22/2023] Open
Abstract
Antibiotic-resistant microbes pose one of the biggest challenges of the current century. While areas with proximity to human impact are closely studied, a lot is yet to learn about antimicrobial resistance in remote regions like the cryosphere. Nowadays, antibiotic (AB) resistance is considered a pollution that has reached the Earth's most pristine areas. However, monitoring of resistant environmental bacteria therein faces several challenges that inhibit scientific progress in this field. Due to many cultivation-based antibiotic susceptibility tests being optimized for mesophilic pathogenic microorganisms, many researchers opt for expensive molecular biological approaches to detect antibiotic resistance in the cryosphere. However, some disadvantages of these methods prohibit effective comprehensive monitoring of resistant bacteria in pristine areas, hence we suggest established cultivation-based approaches when looking for antimicrobial resistance in the cryosphere. In this study, we compared two common antibiotic susceptibility tests and optimized them to meet the needs of psychrophilic microorganisms. The resulting cultures thereof originated from cryospheric habitats with differing anthropogenic impacts. The results show that these methods are applicable to detect antibiotic resistance in cryospheric habitats and could potentially increase the comparability between studies.
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Affiliation(s)
- Daniel Gattinger
- Institute of Ecology, University of Innsbruck, Innsbruck, Austria
| | - Katrin Pichler
- Institute of Ecology, University of Innsbruck, Innsbruck, Austria
| | - Tobias Weil
- Research and Innovation Centre, Fondazione Edmund Mach, All'adige, Italy
| | - Birgit Sattler
- Institute of Ecology, University of Innsbruck, Innsbruck, Austria
- Austrian Polar Research Institute, Vienna, Austria
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26
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Rosazza T, Eigentler L, Earl C, Davidson FA, Stanley‐Wall NR. Bacillus subtilis extracellular protease production incurs a context-dependent cost. Mol Microbiol 2023; 120:105-121. [PMID: 37380434 PMCID: PMC10952608 DOI: 10.1111/mmi.15110] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 06/07/2023] [Accepted: 06/08/2023] [Indexed: 06/30/2023]
Abstract
Microbes encounter a wide range of polymeric nutrient sources in various environmental settings, which require processing to facilitate growth. Bacillus subtilis, a bacterium found in the rhizosphere and broader soil environment, is highly adaptable and resilient due to its ability to utilise diverse sources of carbon and nitrogen. Here, we explore the role of extracellular proteases in supporting growth and assess the cost associated with their production. We provide evidence of the essentiality of extracellular proteases when B. subtilis is provided with an abundant, but polymeric nutrient source and demonstrate the extracellular proteases as a shared public good that can operate over a distance. We show that B. subtilis is subjected to a public good dilemma, specifically in the context of growth sustained by the digestion of a polymeric food source. Furthermore, using mathematical simulations, we uncover that this selectively enforced dilemma is driven by the relative cost of producing the public good. Collectively, our findings reveal how bacteria can survive in environments that vary in terms of immediate nutrient accessibility and the consequent impact on the population composition. These findings enhance our fundamental understanding of how bacteria respond to diverse environments, which has importance to contexts ranging from survival in the soil to infection and pathogenesis scenarios.
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Affiliation(s)
- Thibault Rosazza
- Division of Molecular Microbiology, School of Life ScienceUniversity of DundeeDundeeUK
| | - Lukas Eigentler
- Division of Molecular Microbiology, School of Life ScienceUniversity of DundeeDundeeUK
- Mathematics, School of Science and EngineeringUniversity of DundeeDundeeUK
- Present address:
Evolutionary Biology DepartmentUniversität BielefeldKonsequenz 45Bielefeld33615Germany
| | - Chris Earl
- Division of Molecular Microbiology, School of Life ScienceUniversity of DundeeDundeeUK
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27
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Navarro S, Abla H, Delgado B, Colmer-Hamood JA, Ventolini G, Hamood AN. Glycogen availability and pH variation in a medium simulating vaginal fluid influence the growth of vaginal Lactobacillus species and Gardnerella vaginalis. BMC Microbiol 2023; 23:186. [PMID: 37442975 PMCID: PMC10339506 DOI: 10.1186/s12866-023-02916-8] [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: 03/10/2023] [Accepted: 06/27/2023] [Indexed: 07/15/2023] Open
Abstract
BACKGROUND Glycogen metabolism by Lactobacillus spp. that dominate the healthy vaginal microbiome contributes to a low vaginal pH (3.5-4.5). During bacterial vaginosis (BV), strict and facultative anaerobes including Gardnerella vaginalis become predominant, leading to an increase in the vaginal pH (> 4.5). BV enhances the risk of obstetrical complications, acquisition of sexually transmitted infections, and cervical cancer. Factors critical for the maintenance of the healthy vaginal microbiome or the transition to the BV microbiome are not well defined. Vaginal pH may affect glycogen metabolism by the vaginal microflora, thus influencing the shift in the vaginal microbiome. RESULTS The medium simulating vaginal fluid (MSVF) supported growth of L. jensenii 62G, L. gasseri 63 AM, and L. crispatus JV-V01, and G. vaginalis JCP8151A at specific initial pH conditions for 30 d. L. jensenii at all three starting pH levels (pH 4.0, 4.5, and 5.0), G. vaginalis at pH 4.5 and 5.0, and L. gasseri at pH 5.0 exhibited the long-term stationary phase when grown in MSVF. L. gasseri at pH 4.5 and L. crispatus at pH 5.0 displayed an extended lag phase over 30 d suggesting inefficient glycogen metabolism. Glycogen was essential for the growth of L. jensenii, L. crispatus, and G. vaginalis; only L. gasseri was able to survive in MSVF without glycogen, and only at pH 5.0, where it used glucose. All four species were able to survive for 15 d in MSVF with half the glycogen content but only at specific starting pH levels - pH 4.5 and 5.0 for L. jensenii, L. gasseri, and G. vaginalis and pH 5.0 for L. crispatus. CONCLUSIONS These results suggest that variations in the vaginal pH critically influence the colonization of the vaginal tract by lactobacilli and G. vaginalis JCP8151A by affecting their ability to metabolize glycogen. Further, we found that L. jensenii 62G is capable of glycogen metabolism over a broader pH range (4.0-5.0) while L. crispatus JV-V01 glycogen utilization is pH sensitive (only functional at pH 5.0). Finally, our results showed that G. vaginalis JCP8151A can colonize the vaginal tract for an extended period as long as the pH remains at 4.5 or above.
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Affiliation(s)
- Stephany Navarro
- Department of Immunology and Molecular Microbiology, Texas Tech University Health Sciences Center, Lubbock, TX USA
| | - Habib Abla
- School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX USA
| | - Betsaida Delgado
- Honors College, Texas Tech University, Lubbock, TX USA
- Woody L. Hunt School of Dental Medicine, Texas Tech University Health Sciences Center, Lubbock, TX USA
| | - Jane A. Colmer-Hamood
- Department of Immunology and Molecular Microbiology, Texas Tech University Health Sciences Center, Lubbock, TX USA
- Department of Medical Education, Texas Tech University Health Sciences Center, Lubbock, TX USA
| | - Gary Ventolini
- Department of Obstetrics and Gynecology, Texas Tech University Health Sciences Center Permian Basin, Odessa, TX USA
| | - Abdul N. Hamood
- Department of Immunology and Molecular Microbiology, Texas Tech University Health Sciences Center, Lubbock, TX USA
- Department of Surgery, Texas Tech University Health Sciences Center, Lubbock, TX USA
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28
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Saleh DO, Horstmann JA, Giralt-Zúñiga M, Weber W, Kaganovitch E, Durairaj AC, Klotzsch E, Strowig T, Erhardt M. SPI-1 virulence gene expression modulates motility of Salmonella Typhimurium in a proton motive force- and adhesins-dependent manner. PLoS Pathog 2023; 19:e1011451. [PMID: 37315106 DOI: 10.1371/journal.ppat.1011451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 06/01/2023] [Indexed: 06/16/2023] Open
Abstract
Both the bacterial flagellum and the evolutionary related injectisome encoded on the Salmonella pathogenicity island 1 (SPI-1) play crucial roles during the infection cycle of Salmonella species. The interplay of both is highlighted by the complex cross-regulation that includes transcriptional control of the flagellar master regulatory operon flhDC by HilD, the master regulator of SPI-1 gene expression. Contrary to the HilD-dependent activation of flagellar gene expression, we report here that activation of HilD resulted in a dramatic loss of motility, which was dependent on the presence of SPI-1. Single cell analyses revealed that HilD-activation triggers a SPI-1-dependent induction of the stringent response and a substantial decrease in proton motive force (PMF), while flagellation remains unaffected. We further found that HilD activation enhances the adhesion of Salmonella to epithelial cells. A transcriptome analysis revealed a simultaneous upregulation of several adhesin systems, which, when overproduced, phenocopied the HilD-induced motility defect. We propose a model where the SPI-1-dependent depletion of the PMF and the upregulation of adhesins upon HilD-activation enable flagellated Salmonella to rapidly modulate their motility during infection, thereby enabling efficient adhesion to host cells and delivery of effector proteins.
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Affiliation(s)
- Doaa Osama Saleh
- Institute for Biology/Molecular Microbiology, Humboldt-Universität zu Berlin, Berlin, Germany
- Department of Microbiology and Immunology, Faculty of Pharmacy, Ain Shams University, Cairo, Egypt
| | - Julia A Horstmann
- Junior Research Group Infection Biology of Salmonella, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - María Giralt-Zúñiga
- Institute for Biology/Molecular Microbiology, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Willi Weber
- Institute for Biology, Experimental Biophysics/Mechanobiology, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Eugen Kaganovitch
- Max Planck Institute for Terrestrial Microbiology and Center for Synthetic Microbiology (SYNMIKRO), Marburg, Germany
| | - Abilash Chakravarthy Durairaj
- Junior Research Group Infection Biology of Salmonella, Helmholtz Centre for Infection Research, Braunschweig, Germany
- Department of Microbial Immune Regulation, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Enrico Klotzsch
- Institute for Biology, Experimental Biophysics/Mechanobiology, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Till Strowig
- Department of Microbial Immune Regulation, Helmholtz Centre for Infection Research, Braunschweig, Germany
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany
| | - Marc Erhardt
- Institute for Biology/Molecular Microbiology, Humboldt-Universität zu Berlin, Berlin, Germany
- Max Planck Unit for the Science of Pathogens, Berlin, Germany
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29
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McCully AL, Loop Yao M, Brower KK, Fordyce PM, Spormann AM. Double emulsions as a high-throughput enrichment and isolation platform for slower-growing microbes. ISME COMMUNICATIONS 2023; 3:47. [PMID: 37160952 PMCID: PMC10169782 DOI: 10.1038/s43705-023-00241-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 03/27/2023] [Accepted: 04/12/2023] [Indexed: 05/11/2023]
Abstract
Our understanding of in situ microbial physiology is primarily based on physiological characterization of fast-growing and readily-isolatable microbes. Microbial enrichments to obtain novel isolates with slower growth rates or physiologies adapted to low nutrient environments are plagued by intrinsic biases for fastest-growing species when using standard laboratory isolation protocols. New cultivation tools to minimize these biases and enrich for less well-studied taxa are needed. In this study, we developed a high-throughput bacterial enrichment platform based on single cell encapsulation and growth within double emulsions (GrowMiDE). We showed that GrowMiDE can cultivate many different microorganisms and enrich for underrepresented taxa that are never observed in traditional batch enrichments. For example, preventing dominance of the enrichment by fast-growing microbes due to nutrient privatization within the double emulsion droplets allowed cultivation of slower-growing Negativicutes and Methanobacteria from stool samples in rich media enrichment cultures. In competition experiments between growth rate and growth yield specialist strains, GrowMiDE enrichments prevented competition for shared nutrient pools and enriched for slower-growing but more efficient strains. Finally, we demonstrated the compatibility of GrowMiDE with commercial fluorescence-activated cell sorting (FACS) to obtain isolates from GrowMiDE enrichments. Together, GrowMiDE + DE-FACS is a promising new high-throughput enrichment platform that can be easily applied to diverse microbial enrichments or screens.
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Affiliation(s)
- Alexandra L McCully
- Department of Civil and Environmental Engineering, Stanford University, Stanford, CA, USA
| | - McKenna Loop Yao
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA, USA
| | - Kara K Brower
- Department of Bioengineering, Stanford University, Stanford, CA, USA
| | - Polly M Fordyce
- Department of Bioengineering, Stanford University, Stanford, CA, USA
- Department of Genetics, Stanford University, Stanford, CA, USA
- ChEM-H Institute, Stanford University, Stanford, CA, USA
- Chan Zuckerberg Biohub, San Francisco, CA, USA
| | - Alfred M Spormann
- Department of Civil and Environmental Engineering, Stanford University, Stanford, CA, USA.
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA.
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30
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Catley T, Corrigan RM, Parnell AJ. Designing Effective Antimicrobial Nanostructured Surfaces: Highlighting the Lack of Consensus in the Literature. ACS OMEGA 2023; 8:14873-14883. [PMID: 37151499 PMCID: PMC10157858 DOI: 10.1021/acsomega.2c08068] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 04/07/2023] [Indexed: 05/09/2023]
Abstract
Research into nanostructured materials, inspired by the topography of certain insect wings, has provided a potential pathway toward drug-free antibacterial surfaces, which may be vital in the ongoing battle against antimicrobial resistance. However, to produce viable antibacterial nanostructured surfaces, we must first understand the bactericidal mechanism of action and how to optimize them to kill the widest range of microorganisms. This review discusses the parameters of nanostructured surfaces that have been shown to influence their bactericidal efficiency and highlights the highly variable nature of many of the findings. A large-scale analysis of the literature is also presented, which further shows a lack of clarity in what is understood about the factors influencing bactericidal efficiency. The potential reasons for the ambiguity, including how the killing effect may be a result of multiple factors and issues with nonstandardized testing of the antibacterial properties of nanostructured surfaces, are then discussed. Finally, a standard method for testing of antimicrobial killing is proposed that will allow comparison between studies and enable a deeper understanding about nanostructured surfaces and how to optimize their bactericidal efficiency.
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Affiliation(s)
- Thomas
E. Catley
- Department
of Physics and Astronomy, University of
Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH, United Kingdom
| | - Rebecca M. Corrigan
- Molecular
Microbiology, School of Biosciences, University
of Sheffield, Firth Court, Sheffield S10 2TN, United Kingdom
| | - Andrew J. Parnell
- Department
of Physics and Astronomy, University of
Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH, United Kingdom
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31
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da Silva JL, Mendes LW, Rocha SMB, Antunes JEL, Oliveira LMDS, Melo VMM, Oliveira FAS, Pereira APDA, Costa GDN, da Silva VB, Gomes RLF, de Alcantara Neto F, Lopes ACDA, Araujo ASF. Domestication of Lima Bean (Phaseolus lunatus) Changes the Microbial Communities in the Rhizosphere. MICROBIAL ECOLOGY 2023; 85:1423-1433. [PMID: 35525854 DOI: 10.1007/s00248-022-02028-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 04/26/2022] [Indexed: 05/10/2023]
Abstract
Plants modulate the soil microbiota and select a specific microbial community in the rhizosphere. However, plant domestication reduces genetic diversity, changes plant physiology, and could have an impact on the associated microbiome assembly. Here, we used 16S rRNA gene sequencing to assess the microbial community in the bulk soil and rhizosphere of wild, semi-domesticated, and domesticated genotypes of lima bean (Phaseolus lunatus), to investigate the effect of plant domestication on microbial community assembly. In general, rhizosphere communities were more diverse than bulk soil, but no differences were found among genotypes. Our results showed that the microbial community's structure was different from wild and semi-domesticated as compared to domesticated genotypes. The community similarity decreased 57.67% from wild to domesticated genotypes. In general, the most abundant phyla were Actinobacteria (21.9%), Proteobacteria (20.7%), Acidobacteria (14%), and Firmicutes (9.7%). Comparing the different genotypes, the analysis showed that Firmicutes (Bacillus) was abundant in the rhizosphere of the wild genotypes, while Acidobacteria dominated semi-domesticated plants, and Proteobacteria (including rhizobia) was enriched in domesticated P. lunatus rhizosphere. The domestication process also affected the microbial community network, in which the complexity of connections decreased from wild to domesticated genotypes in the rhizosphere. Together, our work showed that the domestication of P. lunatus shaped rhizosphere microbial communities from taxonomic to a functional level, changing the abundance of specific microbial groups and decreasing the complexity of interactions among them.
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Affiliation(s)
- Josieli Lima da Silva
- Plant Genetic Resource Group, Agricultural Science Center, Federal University of Piauí, Teresina, PI, Brazil
| | - Lucas William Mendes
- Center for Nuclear Energy in Agriculture, University of Sao Paulo, Piracicaba, SP, Brazil
| | - Sandra Mara Barbosa Rocha
- Soil Microbial Ecology Group, Agricultural Science Center, Federal University of Piauí, Teresina, PI, Brazil
| | | | | | - Vania Maria Maciel Melo
- Laboratório de Ecologia Microbiana E Biotecnologia, Federal University of Ceará, Fortaleza, CE, Brazil
| | | | | | - Gérson do Nascimento Costa
- Plant Genetic Resource Group, Agricultural Science Center, Federal University of Piauí, Teresina, PI, Brazil
| | - Veronica Brito da Silva
- Plant Genetic Resource Group, Agricultural Science Center, Federal University of Piauí, Teresina, PI, Brazil
| | - Regina Lucia Ferreira Gomes
- Plant Genetic Resource Group, Agricultural Science Center, Federal University of Piauí, Teresina, PI, Brazil
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Toukabri H, Lereclus D, Slamti L. A Sporulation-Independent Way of Life for Bacillus thuringiensis in the Late Stages of an Infection. mBio 2023:e0037123. [PMID: 37129506 DOI: 10.1128/mbio.00371-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023] Open
Abstract
The formation of endospores has been considered the unique survival and transmission mode of sporulating Firmicutes due to the exceptional resistance and persistence of this bacterial form. However, nonsporulated bacteria (Spo-) were reported at the early stages following the death of a host infected with Bacillus thuringiensis, an entomopathogenic sporulating bacterium. Here, we investigated the characteristics of the bacterial population in the late stages of an infection in the B. thuringiensis/Galleria mellonella infection model. Using fluorescent reporters and molecular markers coupled to flow cytometry, we demonstrated that the Spo- cells persist and constitute about half of the population 2 weeks post-infection (p.i.). Protein synthesis and growth recovery assays indicated that they are in a metabolically slowed-down state. These bacteria were extremely resistant to the insect cadaver environment, which did not support growth of in vitro-grown vegetative cells and spores. A transcriptomic analysis of this subpopulation at 7 days p.i. revealed a signature profile of this state, and the expression analysis of individual genes at the cell level showed that more bacteria mount an oxidative stress response as their survival time increases, in agreement with the increase of the free radical level in the host cadaver and in the number of reactive oxygen species (ROS)-producing bacteria. Altogether, these data show for the first time that nonsporulated bacteria are able to survive for a prolonged period of time in the context of an infection and indicate that they engage in a profound adaptation process that leads to their persistence in the host cadaver. IMPORTANCE Bacillus thuringiensis is an entomopathogenic bacterium widely used as a biopesticide. It belongs to the Bacillus cereus group, comprising the foodborne pathogen B. cereus sensu stricto and the anthrax agent Bacillus anthracis. Like other Firmicutes when they encounter harsh conditions, these Gram-positive bacteria can form dormant cells called spores. Due to its highly resistant nature, the spore was considered the unique mode of long-term survival, eclipsing any other form of persistence. Breaking this paradigm, we observed that B. thuringiensis was able to persist in its host cadaver in a nonsporulated form for at least 14 days. Our results show that these bacteria survived in the cadaver environment, which proved hostile for actively growing bacteria by engaging in a profound adaptation process. Studying this facet of the life cycle of a sporulating bacterium provides new fundamental knowledge and might lead to the development of strategies to combat sporulating pathogenic species.
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Affiliation(s)
- Hasna Toukabri
- Micalis Institute, INRAE, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Didier Lereclus
- Micalis Institute, INRAE, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Leyla Slamti
- Micalis Institute, INRAE, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
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Bailoni E, Partipilo M, Coenradij J, Grundel DAJ, Slotboom DJ, Poolman B. Minimal Out-of-Equilibrium Metabolism for Synthetic Cells: A Membrane Perspective. ACS Synth Biol 2023; 12:922-946. [PMID: 37027340 PMCID: PMC10127287 DOI: 10.1021/acssynbio.3c00062] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Indexed: 04/08/2023]
Abstract
Life-like systems need to maintain a basal metabolism, which includes importing a variety of building blocks required for macromolecule synthesis, exporting dead-end products, and recycling cofactors and metabolic intermediates, while maintaining steady internal physical and chemical conditions (physicochemical homeostasis). A compartment, such as a unilamellar vesicle, functionalized with membrane-embedded transport proteins and metabolic enzymes encapsulated in the lumen meets these requirements. Here, we identify four modules designed for a minimal metabolism in a synthetic cell with a lipid bilayer boundary: energy provision and conversion, physicochemical homeostasis, metabolite transport, and membrane expansion. We review design strategies that can be used to fulfill these functions with a focus on the lipid and membrane protein composition of a cell. We compare our bottom-up design with the equivalent essential modules of JCVI-syn3a, a top-down genome-minimized living cell with a size comparable to that of large unilamellar vesicles. Finally, we discuss the bottlenecks related to the insertion of a complex mixture of membrane proteins into lipid bilayers and provide a semiquantitative estimate of the relative surface area and lipid-to-protein mass ratios (i.e., the minimal number of membrane proteins) that are required for the construction of a synthetic cell.
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Affiliation(s)
- Eleonora Bailoni
- Department
of Biochemistry and Molecular Systems Biology, Groningen Biomolecular
Sciences and Biotechnology Institute, University
of Groningen, Nijenborgh
4, 9747 AG Groningen, The Netherlands
| | - Michele Partipilo
- Department
of Biochemistry and Molecular Systems Biology, Groningen Biomolecular
Sciences and Biotechnology Institute, University
of Groningen, Nijenborgh
4, 9747 AG Groningen, The Netherlands
| | - Jelmer Coenradij
- Department
of Biochemistry and Molecular Systems Biology, Groningen Biomolecular
Sciences and Biotechnology Institute, University
of Groningen, Nijenborgh
4, 9747 AG Groningen, The Netherlands
| | - Douwe A. J. Grundel
- Department
of Biochemistry and Molecular Systems Biology, Groningen Biomolecular
Sciences and Biotechnology Institute, University
of Groningen, Nijenborgh
4, 9747 AG Groningen, The Netherlands
| | - Dirk J. Slotboom
- Department
of Biochemistry and Molecular Systems Biology, Groningen Biomolecular
Sciences and Biotechnology Institute, University
of Groningen, Nijenborgh
4, 9747 AG Groningen, The Netherlands
| | - Bert Poolman
- Department
of Biochemistry and Molecular Systems Biology, Groningen Biomolecular
Sciences and Biotechnology Institute, University
of Groningen, Nijenborgh
4, 9747 AG Groningen, The Netherlands
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Valencio A, da Silva MA, Santos FF, Polatto JM, Machado MMF, Piazza RMF, Gales AC. Capture ELISA for KPC Detection in Gram-Negative Bacilli: Development and Standardisation. Microorganisms 2023; 11:microorganisms11041052. [PMID: 37110475 PMCID: PMC10142090 DOI: 10.3390/microorganisms11041052] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 04/03/2023] [Accepted: 04/05/2023] [Indexed: 04/29/2023] Open
Abstract
The detection of KPC-type carbapenemases is necessary for guiding appropriate antibiotic therapy and the implementation of antimicrobial stewardship and infection control measures. Currently, few tests are capable of differentiating carbapenemase types, restricting the lab reports to their presence or not. The aim of this work was to raise antibodies and develop an ELISA test to detect KPC-2 and its D179 mutants. The ELISA-KPC test was designed using rabbit and mouse polyclonal antibodies. Four different protocols were tested to select the bacterial inoculum with the highest sensitivity and specificity rates. The standardisation procedure was performed using 109 previously characterised clinical isolates, showing 100% of sensitivity and 89% of specificity. The ELISA-KPC detected all isolates producing carbapenemases, including KPC variants displaying the ESBL phenotype such as KPC-33 and -66.
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Affiliation(s)
- André Valencio
- Division of Infectious Diseases, Department of Internal Medicine, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo 04039-032, Brazil
| | | | - Fernanda Fernandes Santos
- Division of Infectious Diseases, Department of Internal Medicine, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo 04039-032, Brazil
| | | | - Marcelo Marcondes Ferreira Machado
- Division of Infectious Diseases, Department of Internal Medicine, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo 04039-032, Brazil
| | | | - Ana Cristina Gales
- Division of Infectious Diseases, Department of Internal Medicine, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo 04039-032, Brazil
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Wang X, Wang J, Liu SY, Guo JS, Fang F, Chen YP, Yan P. Mechanisms of survival mediated by the stringent response in Pseudomonas aeruginosa under environmental stress in drinking water systems: Nitrogen deficiency and bacterial competition. JOURNAL OF HAZARDOUS MATERIALS 2023; 448:130941. [PMID: 36758433 DOI: 10.1016/j.jhazmat.2023.130941] [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: 09/02/2022] [Revised: 02/01/2023] [Accepted: 02/02/2023] [Indexed: 06/18/2023]
Abstract
Pseudomonas aeruginosa causes public health problems in drinking water systems. This study investigated the potential role of the stringent response in regulating the adaptive physiological metabolic behaviors of P. aeruginosa to low nitrogen stress and bacterial competition in drinking water systems. The results indicated that guanosine tetraphosphate (ppGpp) concentrations in P. aeruginosa increased to 135.5 pmol/g SS under short-term nitrogen deficiency. Meanwhile, the expression levels of the ppGpp synthesis genes (ppx, relA) and degradation gene (spoT) were upregulated by 37.0% and downregulated by 26.8%, respectively, indicating that the stringent response was triggered. The triggered stringent response inhibited the growth of P. aeruginosa and enhanced the metabolic activity of P. aeruginosa to adapt to nutrient deprivation. The interspecific competition significantly affected the regulation of the stringent response in P. aeruginosa. During short-term nitrogen deficiency, the extracellular polymeric substances concentration of P. aeruginosa decreased significantly, leading to desorption and diffusion of attached bacteria and increased ecological risks. The regulatory effect of stringent response on P. aeruginosa gradually weakened under long-term nitrogen deficiency. However, the expression of pathogenic genes (nalD/PA3310) and flagellar assembly genes (fliC) in P. aeruginosa was upregulated by the stringent response, which increased the risk of disease.
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Affiliation(s)
- Xu Wang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China; College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Jing Wang
- Chongqing Jianzhu College, Chongqing 400072, China
| | - Shao-Yang Liu
- Department of Chemistry and Physics, Troy University, Troy, AL 36082, USA
| | - Jin-Song Guo
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China; College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Fang Fang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China; College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - You-Peng Chen
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China; College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Peng Yan
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China; College of Environment and Ecology, Chongqing University, Chongqing 400045, China.
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Kim W, Kim M, Park W. Unlocking the mystery of lysine toxicity on Microcystis aeruginosa. JOURNAL OF HAZARDOUS MATERIALS 2023; 448:130932. [PMID: 36860069 DOI: 10.1016/j.jhazmat.2023.130932] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Revised: 01/19/2023] [Accepted: 01/31/2023] [Indexed: 06/18/2023]
Abstract
Lysine toxicity on certain groups of bacterial cells has been recognized for many years, but the detailed molecular mechanisms that drive this phenomenon have not been elucidated. Many cyanobacteria including Microcystis aeruginosa cannot efficiently export and degrade lysine, although they have evolved to maintain a single copy of the lysine uptake system through which arginine or ornithine can also be transported into the cytoplasm. Autoradiographic analysis using 14C-l-lysine confirmed that lysine was competitively uptaken into cells with arginine or ornithine, which explained the arginine or ornithine-mediated alleviation of lysine toxicity in M. aeruginosa. A relatively non-specific MurE amino acid ligase could incorporate l-lysine into the 3rd position of UDP-N-acetylmuramyl-tripeptide by replacing meso-diaminopimelic acid during the stepwise addition of amino acids on peptidoglycan (PG) biosynthesis. However, further transpeptidation was blocked because lysine substitution at the pentapeptide of the cell wall inhibited the activity of transpeptidases. The leaky PG structure caused irreversible damage to the photosynthetic system and membrane integrity. Collectively, our results suggest that a lysine-mediated coarse-grained PG network and the absence of concrete septal PG lead to the death of slow-growing cyanobacteria.
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Affiliation(s)
- Wonjae Kim
- Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul 02841, Republic of Korea
| | - Minkyung Kim
- Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul 02841, Republic of Korea
| | - Woojun Park
- Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul 02841, Republic of Korea.
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37
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Bourgault AM, Deb C, Aguirre L, Xie R, Rathbun KP, Sole ML. Microbiome profile informs cleansing and storage practices for reusable feeding tube stylets in critical care. Nutr Clin Pract 2023; 38:411-424. [PMID: 35985807 DOI: 10.1002/ncp.10904] [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: 03/15/2022] [Revised: 06/13/2022] [Accepted: 07/16/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Cleansing and storage practices for reusable feeding tube stylets are varied and lack consensus guidelines. Almost 40% of critical care nurses do not cleanse reusable stylets. Our proof-of-concept study aimed to identify potential microbial contamination of stylets before and after cleansing with 70% isopropyl alcohol to establish practice standards. METHODS This prospective, exploratory pilot study sampled reusable feeding tube stylets using three different stylet sample sets. Set 1 included human participant stylets sampled for microbiome profile precleansing, and postcleansing and reinsertion into feeding tubes (n = 4). Sets 2 and 3 included stylets stored at the bedside. Set 2 included precleansed stylets for microbiome profiles (n = 5). Set 3 included precleansed and postcleansed stylets sampled for quantitative cultures (n = 5). Careful handling and storage protocols were used. Microbiome profiling used 16s ribosomal RNA gene amplicon sequencing. RESULTS Bacterial species identified on stylets were primarily common microflora and opportunistic pathogens, including Streptococcus pneumoniae, Staphylococcus aureus, Pseudomonas fulva, Cutibacterium acnes, Prevotella melaninogenica, and Lactobacillus paracasei. Microbiological culturing of stylet samples (set 3) did not yield growth for 9/10 samples; Staphylococcus capitis was identified in one postcleansed sample. Mean bacterial species diversity (alpha diversity) decreased following alcohol cleansing (M = 2.54 pre, M = 1.5 post; P = 0.006). CONCLUSION The abundance of several potentially opportunistic pathogens indicated plausible risk for gut contamination secondary to reinsertion of stylets into small-bore feeding tubes. Stylet cleansing with 70% isopropyl alcohol reduced bacterial burden on the stylets, although viability was unknown. Careful cleansing, handling, and storage protocols for reusable stylets are necessary to minimize contamination.
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Affiliation(s)
- Annette M Bourgault
- Academic Health Science Center, College of Nursing, University of Central Florida, Orlando, Florida, USA
| | - Chirajyoti Deb
- Translational Medicine Research, Translational Research and Specialty Diagnostic Laboratory, Orlando Health, Orlando, Florida
| | - Lillian Aguirre
- Trauma/Burn Critical Care, Orlando Regional Medical Center, a part of Orlando Health, Orlando, Florida
| | - Rui Xie
- Department of Statistics and Data Science, University of Central Florida, Orlando, Florida
| | - Kimberly Paige Rathbun
- Academic Health Science Center, College of Nursing, University of Central Florida, Orlando, Florida, USA
| | - Mary Lou Sole
- Academic Health Science Center, College of Nursing, University of Central Florida, Orlando, Florida, USA
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Denitrification by Bradyrhizobia under Feast and Famine and the Role of the bc1 Complex in Securing Electrons for N 2O Reduction. Appl Environ Microbiol 2023; 89:e0174522. [PMID: 36662572 PMCID: PMC9972998 DOI: 10.1128/aem.01745-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Rhizobia living as microsymbionts inside nodules have stable access to carbon substrates, but also must survive as free-living bacteria in soil where they are starved for carbon and energy most of the time. Many rhizobia can denitrify, thus switch to anaerobic respiration under low O2 tension using N-oxides as electron acceptors. The cellular machinery regulating this transition is relatively well known from studies under optimal laboratory conditions, while little is known about this regulation in starved organisms. It is, for example, not known if the strong preference for N2O- over NO3- reduction in bradyrhizobia is retained under carbon limitation. Here, we show that starved cultures of a Bradyrhizobium strain with respiration rates 1 to 18% of well-fed cultures reduced all available N2O before touching provided NO3-. These organisms, which carry out complete denitrification, have the periplasmic nitrate reductase NapA but lack the membrane-bound nitrate reductase NarG. Proteomics showed similar levels of NapA and NosZ (N2O reductase), excluding that the lack of NO3- reduction was due to low NapA abundance. Instead, this points to a metabolic-level phenomenon where the bc1 complex, which channels electrons to NosZ via cytochromes, is a much stronger competitor for electrons from the quinol pool than the NapC enzyme, which provides electrons to NapA via NapB. The results contrast the general notion that NosZ activity diminishes under carbon limitation and suggest that bradyrhizobia carrying NosZ can act as strong sinks for N2O under natural conditions, implying that this criterion should be considered in the development of biofertilizers. IMPORTANCE Legume cropped farmlands account for substantial N2O emissions globally. Legumes are commonly inoculated with N2-fixing bacteria, rhizobia, to improve crop yields. Rhizobia belonging to Bradyrhizobium, the microsymbionts of several economically important legumes, are generally capable of denitrification but many lack genes encoding N2O reductase and will be N2O sources. Bradyrhizobia with complete denitrification will instead act as sinks since N2O-reduction efficiently competes for electrons over nitrate reduction in these organisms. This phenomenon has only been demonstrated under optimal conditions and it is not known how carbon substrate limitation, which is the common situation in most soils, affects the denitrification phenotype. Here, we demonstrate that bradyrhizobia retain their strong preference for N2O under carbon starvation. The findings add basic knowledge about mechanisms controlling denitrification and support the potential for developing novel methods for greenhouse gas mitigation based on legume inoculants with the dual capacity to optimize N2 fixation and minimize N2O emission.
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Corona Ramírez A, Lee KS, Odriozola A, Kaminek M, Stocker R, Zuber B, Junier P. Multiple roads lead to Rome: unique morphology and chemistry of endospores, exospores, myxospores, cysts and akinetes in bacteria. MICROBIOLOGY (READING, ENGLAND) 2023; 169. [PMID: 36804869 DOI: 10.1099/mic.0.001299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
The production of specialized resting cells is a remarkable survival strategy developed by many organisms to withstand unfavourable environmental factors such as nutrient depletion or other changes in abiotic and/or biotic conditions. Five bacterial taxa are recognized to form specialized resting cells: Firmicutes, forming endospores; Actinobacteria, forming exospores; Cyanobacteria, forming akinetes; the δ-Proteobacterial order Myxococcales, forming myxospores; and Azotobacteraceae, forming cysts. All these specialized resting cells are characterized by low-to-absent metabolic activity and higher resistance to environmental stress (desiccation, heat, starvation, etc.) when compared to vegetative cells. Given their similarity in function, we tested the potential existence of a universal morpho-chemical marker for identifying these specialized resting cells. After the production of endospores, exospores, akinetes and cysts in model organisms, we performed the first cross-species morphological and chemical comparison of bacterial sporulation. Cryo-electron microscopy of vitreous sections (CEMOVIS) was used to describe near-native morphology of the resting cells in comparison to the morphology of their respective vegetative cells. Resting cells shared a thicker cell envelope as their only common morphological feature. The chemical composition of the different specialized resting cells at the single-cell level was investigated using confocal Raman microspectroscopy. Our results show that the different specialized cells do not share a common chemical signature, but rather each group has a unique signature with a variable conservation of the signature of the vegetative cells. Additionally, we present the validation of Raman signatures associated with calcium dipicolinic acid (CaDPA) and their variation across individual cells to develop specific sorting thresholds for the isolation of endospores. This provides a proof of concept of the feasibility of isolating bacterial spores using a Raman-activated cell-sorting platform. This cross-species comparison and the current knowledge of genetic pathways inducing the formation of the resting cells highlights the complexity of this convergent evolutionary strategy promoting bacterial survival.
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Affiliation(s)
- Andrea Corona Ramírez
- Laboratory of Microbiology, Institute of Biology, University of Neuchatel, Neuchatel, Switzerland
| | - Kang Soo Lee
- Department of Civil, Institute for Environmental Engineering, Environmental and Geomatic Engineering, ETH Zurich, Zurich, Switzerland
| | | | - Marek Kaminek
- Institute of Anatomy, University of Bern, Bern, Switzerland
| | - Roman Stocker
- Department of Civil, Institute for Environmental Engineering, Environmental and Geomatic Engineering, ETH Zurich, Zurich, Switzerland
| | - Benoît Zuber
- Institute of Anatomy, University of Bern, Bern, Switzerland
| | - Pilar Junier
- Laboratory of Microbiology, Institute of Biology, University of Neuchatel, Neuchatel, Switzerland
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Wagley S. The Viable but Non-Culturable (VBNC) State in Vibrio Species: Why Studying the VBNC State Now Is More Exciting than Ever. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1404:253-268. [PMID: 36792880 DOI: 10.1007/978-3-031-22997-8_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
During periods that are not conducive for growth or when facing stressful conditions, Vibrios enter a dormant state called the Viable But Non-Culturable (VBNC) state. In this chapter, I will analyse the role of the VBNC state in Vibrio species survival and pathogenesis and the molecular mechanisms regulating this complex phenomenon. I will emphasise some of the novel findings that make studying the VBNC state now more exciting than ever and its significance in the epidemiology of these pathogens and critical role in food safety.
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Affiliation(s)
- Sariqa Wagley
- Biosciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, Devon, UK.
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Suyama T, Kanno N, Matsukura S, Chihara K, Noda N, Hanada S. Transcriptome and Deletion Mutant Analyses Revealed that an RpoH Family Sigma Factor Is Essential for Photosystem Production in Roseateles depolymerans under Carbon Starvation. Microbes Environ 2023; 38. [PMID: 36878600 PMCID: PMC10037100 DOI: 10.1264/jsme2.me22072] [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] [Indexed: 03/08/2023] Open
Abstract
Roseateles depolymerans is an obligately aerobic bacterium that produces a photosynthetic apparatus only under the scarcity of carbon substrates. We herein examined changes in the transcriptomes of R. depolymerans cells to clarify the expression of photosynthesis genes and their upstream regulatory factors under carbon starvation. Transcriptomes 0, 1, and 6 h after the depletion of a carbon substrate indicated that transcripts showing the greatest variations (a 500-fold increase [6 h/0 h]) were light-harvesting proteins (PufA and PufB). Moreover, loci with more than 50-fold increases (6 h/0 h) were fully related to the photosynthetic gene cluster. Among 13 sigma factor genes, the transcripts of a sigma 70 family sigma factor related to RpoH (SP70) increased along photosynthesis genes under starvation; therefore, a knockout experiment of SP70 was performed. ΔSP70 mutants were found to lack photosynthetic pigments (carotenoids and bacteriochlo-rophyll a) regardless of carbon starvation. We also examined the effects of heat stress on ΔSP70 mutants, and found that SP70 was also related to heat stress tolerance, similar to other RpoH sigma factors (while heat stress did not trigger photosystem production). The deficient accumulation of photosynthetic pigments and the heat stress tolerance of ΔSP70 mutants were both complemented by the introduction of an intact SP70 gene. Furthermore, the transcription of photosynthetic gene operons (puf, puh, and bch) was markedly reduced in the ΔSP70 mutant. The RpoH homologue SP70 was concluded to be a sigma factor that is essential for the transcription of photosynthetic gene operons in R. depolymerans.
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Affiliation(s)
- Tetsushi Suyama
- Bio-Analytical Research Group, Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST)
| | - Nanako Kanno
- Photosynthetic Microbial Consortia Laboratory, Department of Biological Sciences, Graduate School of Science, Tokyo Metropolitan University
| | - Satoko Matsukura
- Bio-Analytical Research Group, Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST)
| | - Kotaro Chihara
- Bio-Analytical Research Group, Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST)
- Department of Life Science and Medical Bioscience, Waseda University
| | - Naohiro Noda
- Bio-Analytical Research Group, Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST)
- Department of Life Science and Medical Bioscience, Waseda University
| | - Satoshi Hanada
- Photosynthetic Microbial Consortia Laboratory, Department of Biological Sciences, Graduate School of Science, Tokyo Metropolitan University
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Sierra MA, Ryon KA, Tierney BT, Foox J, Bhattacharya C, Afshin E, Butler D, Green SJ, Thomas WK, Ramsdell J, Bivens NJ, McGrath K, Mason CE, Tighe SW. Microbiome and metagenomic analysis of Lake Hillier Australia reveals pigment-rich polyextremophiles and wide-ranging metabolic adaptations. ENVIRONMENTAL MICROBIOME 2022; 17:60. [PMID: 36544228 PMCID: PMC9768965 DOI: 10.1186/s40793-022-00455-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 12/01/2022] [Indexed: 06/17/2023]
Abstract
Lake Hillier is a hypersaline lake known for its distinctive bright pink color. The cause of this phenomenon in other hypersaline sites has been attributed to halophiles, Dunaliella, and Salinibacter, however, a systematic analysis of the microbial communities, their functional features, and the prevalence of pigment-producing-metabolisms has not been previously studied. Through metagenomic sequencing and culture-based approaches, our results evidence that Lake Hillier is composed of a diverse set of microorganisms including archaea, bacteria, algae, and viruses. Our data indicate that the microbiome in Lake Hillier is composed of multiple pigment-producer microbes, including Dunaliella, Salinibacter, Halobacillus, Psychroflexus, Halorubrum, many of which are cataloged as polyextremophiles. Additionally, we estimated the diversity of metabolic pathways in the lake and determined that many of these are related to pigment production. We reconstructed complete or partial genomes for 21 discrete bacteria (N = 14) and archaea (N = 7), only 2 of which could be taxonomically annotated to previously observed species. Our findings provide the first metagenomic study to decipher the source of the pink color of Australia's Lake Hillier. The study of this pink hypersaline environment is evidence of a microbial consortium of pigment producers, a repertoire of polyextremophiles, a core microbiome and potentially novel species.
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Affiliation(s)
- Maria A Sierra
- Tri-Institutional Computational Biology and Medicine Program, Weill Cornell Medicine, New York, NY, USA
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, 10065, USA
| | - Krista A Ryon
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, 10065, USA
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY, 10065, USA
| | - Braden T Tierney
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, 10065, USA
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY, 10065, USA
| | - Jonathan Foox
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, 10065, USA
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY, 10065, USA
| | - Chandrima Bhattacharya
- Tri-Institutional Computational Biology and Medicine Program, Weill Cornell Medicine, New York, NY, USA
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, 10065, USA
| | - Evan Afshin
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, 10065, USA
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY, 10065, USA
| | - Daniel Butler
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY, 10065, USA
| | - Stefan J Green
- Genomics and Microbiome Core Facility, Rush University, New York, IL, USA
| | - W Kelley Thomas
- Department of Molecular, Cellular, and Biomedical Sciences, College of Life Sciences and Agriculture, University of New Hampshire, Durham, NH, USA
| | | | - Nathan J Bivens
- DNA Core Facility, University of Missouri, Columbia, MO, USA
| | | | - Christopher E Mason
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, 10065, USA.
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY, 10065, USA.
- WorldQuant Initiative for Quantitative Prediction, Weill Cornell Medicine, New York, NY, USA.
- The Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA.
| | - Scott W Tighe
- Advanced Genomics Laboratory, University of Vermont Cancer Center, University of Vermont, Burlington, VT, USA.
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NtrC Increases Fitness of Salmonella enterica Serovar Typhimurium under Low and Fluctuating Nutrient Conditions. J Bacteriol 2022; 204:e0026422. [PMID: 36317920 PMCID: PMC9765038 DOI: 10.1128/jb.00264-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Enteric pathogens cycle between nutrient-rich host and nutrient-poor external environment. These pathogens compete for nutrients while cycling between host and external environment, and often experience starvation. In this context, we have studied the role of a global regulator (NtrC) of Salmonella Typhimurium. The ntrC knockout mutation caused extended lag phase (8 h) and slow growth in the minimal medium. In lag phase, the wild-type cells showed ~60-fold more expression of ntrC gene. Gene expression studies and biochemical assays showed that the extended lag phase and slow growth is due to slow metabolism, instead of nitrogen transport. Further, we observed that ntrC knockout mutation led extended lag phase and slow growth, made ΔntrC mutant unable to compete with wild-type S. Typhimurium in both static and fluctuating nutrient condition. In addition to this, ΔntrC knockout mutant was unable to survive long-term nitrogen starvation (150 days). The nutrient recycling assays and gene expression studies revealed that ntrC gene is essential for rapid recycling of nutrients from the dead cells. Moreover, in the absence of ntrC gene, magnesium limits the nutrient recycling efficiency of S. Typhimurium. Therefore, the ntrC gene, which is often studied with respect to nitrogen scavenging in a low nitrogen growing condition, is required even in the adequate supply of nitrogen to maintain optimal growth and fast exit from the lag phase. Hence, we conclude that, the ntrC expression is essential for competitive fitness of S. Typhimurium under the low and fluctuating nutrient condition. IMPORTANCE S. Typhimurium, both in host and external environment, faces enormous competition from other microorganisms. The competition may take place either in static or in fluctuating nutrient conditions. Thus, how S. Typhimurium survives under such overlapping stress conditions remained unclear. Therefore, using S. Typhimurium as model organism we report that a global regulator NtrC, found in enteric bacteria like Escherichia coli and Salmonella, activates the set of genes and operons involved in rapid adaptation and efficient nutrient recycling/scavenging. These properties enable cells to compete with other microbes under the characteristic feast-or-famine lifestyle of S. Typhimurium. Therefore, this work helps us to understand the starvation physiology of the enteric bacterial pathogen S. Typhimurium.
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Prado T, Brandão ML, Fumian TM, Freitas L, Chame M, Leomil L, Magalhães MGP, Degrave WMS, Leite JPG, Miagostovich MP. Virome analysis in lakes of the South Shetland Islands, Antarctica - 2020. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 852:158537. [PMID: 36075413 DOI: 10.1016/j.scitotenv.2022.158537] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 08/05/2022] [Accepted: 09/01/2022] [Indexed: 05/25/2023]
Abstract
Polar freshwater ecosystems are characterized by a distinct microbiota. However, little is known about viral diversity and abundance, especially regarding the ecology of RNA viruses. We used shotgun metagenomic analysis on samples from Antarctic ecosystems, and report here the characterization of the virome fraction, from different lakes located in the South Shetland Islands (Penguin, Ardley, Deception and King George Island) in the Peninsula Antarctica, in the summer season 2020. DNA viruses (99.4 %) prevailed over RNA viruses (0.6 %) in the lake samples. Six viral orders were identified in the metagenomic libraries: Caudovirales (dsDNA), which was prevalent in most lakes; Picornavirales (ssRNA+); Sobelivirales (ssRNA+); Tolivirales (ssRNA+); Petitvirales (ssDNA) and Baphyvirales (ssDNA), including eight viral families (Herelleviridae, Siphoviridae, Myoviridae, Microviridae, Marnaviridae, Bacilladnaviridae, Barnaviridae and Tombusviridae) and several other, mainly non-classified ssRNA(+) viruses in the lakes of Ardley Island. Bacteriophages (dsDNA) (Herelleviridae family) infecting the phylum Firmicutes and Siphoviridae were predominant in most lakes evaluated. Functional analysis demonstrated a prevalence of unknown proteins (68 %) in the virome. Our prospective study provides virome analysis data from different lakes in the South Shetland Islands, Antarctica, opening exploratory lines for future research related to the biodiversity and viral ecology in this extreme ecosystem.
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Affiliation(s)
- Tatiana Prado
- Laboratory of Comparative and Environmental Virology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Av. Brasil, 4365, Manguinhos, Rio de Janeiro, CEP 21040-360, Brazil.
| | - Martha Lima Brandão
- FioAntar Project/ VPPIS - Fiocruz, Av Brasil 4365, Manguinhos, Rio de Janeiro, RJ 21040-360, Brazil
| | - Tulio Machado Fumian
- Laboratory of Comparative and Environmental Virology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Av. Brasil, 4365, Manguinhos, Rio de Janeiro, CEP 21040-360, Brazil
| | - Lucas Freitas
- Laboratory of Respiratory Virus and Measles, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Av. Brasil, 4365, Manguinhos, Rio de Janeiro CEP 21040-360, Brazil
| | - Marcia Chame
- Institutional Platform for Biodiversity and Wildlife Health, Av Brasil 4365, Manguinhos, Rio de Janeiro, RJ 21040-360, Brazil
| | - Luciana Leomil
- SENAI Innovation Institute for Biosynthetics and Fibers, Technology Center for Chemical and Textile Industry, 4° Andar: Biotecnologia, Rua Fernando de Souza Barros, 120, Parque Tecnológico da UFRJ, Cidade Universitária, Rio de Janeiro CEP 21941-857, Brazil
| | - Maithê Gaspar Pontes Magalhães
- Laboratory of Functional Genomics and Bioinformatics, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Av. Brasil, 4365, Manguinhos, Rio de Janeiro, RJ 21040-360, Brazil
| | - Wim Maurits Sylvain Degrave
- Laboratory of Functional Genomics and Bioinformatics, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Av. Brasil, 4365, Manguinhos, Rio de Janeiro, RJ 21040-360, Brazil
| | - José Paulo Gagliardi Leite
- Laboratory of Comparative and Environmental Virology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Av. Brasil, 4365, Manguinhos, Rio de Janeiro, CEP 21040-360, Brazil
| | - Marize Pereira Miagostovich
- Laboratory of Comparative and Environmental Virology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Av. Brasil, 4365, Manguinhos, Rio de Janeiro, CEP 21040-360, Brazil
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Cesar S, Sun J, Huang KC. Cellular memory of rapid growth is sensitive to nutrient depletion during starvation. Front Microbiol 2022; 13:1016371. [DOI: 10.3389/fmicb.2022.1016371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Accepted: 11/01/2022] [Indexed: 11/22/2022] Open
Abstract
Bacteria frequently encounter nutrient fluctuations in natural environments, yet we understand little about their ability to maintain physiological memory of previous food sources. Starvation is a particularly acute case, in which cells must balance adaptation to stresses with limited nutrient supply. Here, we show that Escherichia coli cells immediately accelerate and decelerate in growth upon transitions from spent to fresh media and vice versa, respectively, and memory of rapid growth can be maintained for many hours under constant flow of spent medium. However, after transient exposure of stationary-phase cells to fresh medium, subsequent aerobic incubation in increasingly spent medium led to lysis and limited growth when rejuvenated in fresh medium. Growth defects were avoided by incubation in anaerobic spent medium or water, suggesting that defects were caused by respiration during the process of nutrient depletion in spent medium. These findings highlight the importance of respiration for stationary phase survival and underscore the broad range of starvation outcomes depending on environmental history.
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Sim S, Hui Y, Tirrell DA. 3D-Printable Cellular Composites for the Production of Recombinant Proteins. Biomacromolecules 2022; 23:4687-4695. [DOI: 10.1021/acs.biomac.2c00915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Seunghyun Sim
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Yue Hui
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - David A. Tirrell
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
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Goodman AZ, Papudeshi B, Doane MP, Mora M, Kerr E, Torres M, Nero Moffatt J, Lima L, Nosal AP, Dinsdale E. Epidermal Microbiomes of Leopard Sharks ( Triakis semifasciata) Are Consistent across Captive and Wild Environments. Microorganisms 2022; 10:microorganisms10102081. [PMID: 36296361 PMCID: PMC9610875 DOI: 10.3390/microorganisms10102081] [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: 08/23/2022] [Revised: 10/14/2022] [Accepted: 10/18/2022] [Indexed: 01/24/2023] Open
Abstract
Characterizations of shark-microbe systems in wild environments have outlined patterns of species-specific microbiomes; however, whether captivity affects these trends has yet to be determined. We used high-throughput shotgun sequencing to assess the epidermal microbiome belonging to leopard sharks (Triakis semifasciata) in captive (Birch Aquarium, La Jolla California born and held permanently in captivity), semi-captive (held in captivity for <1 year in duration and scheduled for release; Scripps Institute of Oceanography, San Diego, CA, USA) and wild environments (Moss Landing and La Jolla, CA, USA). Here, we report captive environments do not drive epidermal microbiome compositions of T. semifasciata to significantly diverge from wild counterparts as life-long captive sharks maintain a species-specific epidermal microbiome resembling those associated with semi-captive and wild populations. Major taxonomic composition shifts observed were inverse changes of top taxonomic contributors across captive duration, specifically an increase of Pseudoalteromonadaceae and consequent decrease of Pseudomonadaceae relative abundance as T. semifasciata increased duration in captive conditions. Moreover, we show captivity did not lead to significant losses in microbial α-diversity of shark epidermal communities. Finally, we present a novel association between T. semifasciata and the Muricauda genus as Metagenomes associated genomes revealed a consistent relationship across captive, semi-captive, and wild populations. Since changes in microbial communities is often associated with poor health outcomes, our report illustrates that epidermally associated microbes belonging to T. semifasciata are not suffering detrimental impacts from long or short-term captivity. Therefore, conservation programs which house sharks in aquariums are providing a healthy environment for the organisms on display. Our findings also expand on current understanding of shark epidermal microbiomes, explore the effects of ecologically different scenarios on benthic shark microbe associations, and highlight novel associations that are consistent across captive gradients.
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Affiliation(s)
- Asha Z. Goodman
- Department of Biology, San Diego State University, San Diego, CA 92182, USA
- Correspondence: (A.Z.G.); (E.D.)
| | - Bhavya Papudeshi
- College of Science and Engineering, Flinders University, Bedford Park, SA 3929, Australia
| | - Michael P. Doane
- College of Science and Engineering, Flinders University, Bedford Park, SA 3929, Australia
| | - Maria Mora
- Department of Biology, San Diego State University, San Diego, CA 92182, USA
| | - Emma Kerr
- Department of Biology, San Diego State University, San Diego, CA 92182, USA
| | - Melissa Torres
- Scripps Institution of Oceanography, Universtity of California, San Diego, CA 92093, USA
| | - Jennifer Nero Moffatt
- Scripps Institution of Oceanography, Universtity of California, San Diego, CA 92093, USA
| | - Lais Lima
- Department of Biology, San Diego State University, San Diego, CA 92182, USA
| | - Andrew P. Nosal
- Department of Biology, Point Loma Nazarene University, San Diego, CA 92106, USA
| | - Elizabeth Dinsdale
- College of Science and Engineering, Flinders University, Bedford Park, SA 3929, Australia
- Correspondence: (A.Z.G.); (E.D.)
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Sun H, Xia J, Wu B, Ren H, Zhang X, Ye L. Aerobic starvation treatment of activated sludge enhances the degradation efficiency of refractory organic compounds. WATER RESEARCH 2022; 224:119069. [PMID: 36108399 DOI: 10.1016/j.watres.2022.119069] [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: 05/22/2022] [Revised: 09/04/2022] [Accepted: 09/05/2022] [Indexed: 06/15/2023]
Abstract
Many refractory organic compounds (ROCs) in wastewater are toxic to human and aquatic organisms. Here, we reported an aerobic starvation approach to improve the degradation efficiencies of ROCs in activated sludge systems. The highest degradation rates of bisphenol AF (BPAF) (11.4 mg/g VSS · h) and gabapentin (GBP) (8.9 mg/g VSS · h) were achieved on the second day of the starvation process. While, the degradation rate of bisphenol A (BPA) on the 43rd day reached the maximum value of 0.8 mg/g VSS ·h, which was significantly higher than that of the seeding sludge (0.01 mg/g VSS · h). To investigate the mechanisms of this finding, we applied magnetic-nanoparticle mediated isolation, 16S rRNA gene sequencing, metagenomic sequencing and metatranscriptomic sequencing to analyze the microbial community structures and functions during the starvation process. The results showed that the increase of the BPA degradation ability was caused by the increase of the relative abundance of BPA degrading bacteria (Sphingomonas, Achromobacter, etc.), while, the enhancement of BPAF and GBP degradation was attributed to the increase of the expression of ROC degrading genes. Overall, these results improve our understanding of the microbial ecology of starved activated sludge and provide useful information for the future development of ROC removal technologies.
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Affiliation(s)
- Haohao Sun
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, China
| | - Juntao Xia
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, China
| | - Bing Wu
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, China
| | - Hongqiang Ren
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, China
| | - Xuxiang Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, China.
| | - Lin Ye
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, China.
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Reconstruction and Analysis of Thermodynamically Constrained Models Reveal Metabolic Responses of a Deep-Sea Bacterium to Temperature Perturbations. mSystems 2022; 7:e0058822. [PMID: 35950761 PMCID: PMC9426432 DOI: 10.1128/msystems.00588-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Microbial acclimation to different temperature conditions can involve broad changes in cell composition and metabolic efficiency. A systems-level view of these metabolic responses in nonmesophilic organisms, however, is currently missing. In this study, thermodynamically constrained genome-scale models were applied to simulate the metabolic responses of a deep-sea psychrophilic bacterium, Shewanella psychrophila WP2, under suboptimal (4°C), optimal (15°C), and supraoptimal (20°C) growth temperatures. The models were calibrated with experimentally determined growth rates of WP2. Gibbs free energy change of reactions (ΔrG'), metabolic fluxes, and metabolite concentrations were predicted using random simulations to characterize temperature-dependent changes in the metabolism. The modeling revealed the highest metabolic efficiency at the optimal temperature, and it suggested distinct patterns of ATP production and consumption that could lead to lower metabolic efficiency under suboptimal or supraoptimal temperatures. The modeling also predicted rearrangement of fluxes through multiple metabolic pathways, including the glycolysis pathway, Entner-Doudoroff pathway, tricarboxylic acid (TCA) cycle, and electron transport system, and these predictions were corroborated through comparisons to WP2 transcriptomes. Furthermore, predictions of metabolite concentrations revealed the potential conservation of reducing equivalents and ATP in the suboptimal temperature, consistent with experimental observations from other psychrophiles. Taken together, the WP2 models provided mechanistic insights into the metabolism of a psychrophile in response to different temperatures. IMPORTANCE Metabolic flexibility is a central component of any organism's ability to survive and adapt to changes in environmental conditions. This study represents the first application of thermodynamically constrained genome-scale models in simulating the metabolic responses of a deep-sea psychrophilic bacterium to various temperatures. The models predicted differences in metabolic efficiency that were attributed to changes in metabolic pathway utilization and metabolite concentration during growth under optimal and nonoptimal temperatures. Experimental growth measurements were used for model calibration, and temperature-dependent transcriptomic changes corroborated the model-predicted rearrangement of metabolic fluxes. Overall, this study highlights the utility of modeling approaches in studying the temperature-driven metabolic responses of an extremophilic organism.
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Wang D, Ning Q, Deng Z, Zhang M, You J. Role of environmental stresses in elevating resistance mutations in bacteria: Phenomena and mechanisms. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 307:119603. [PMID: 35691443 DOI: 10.1016/j.envpol.2022.119603] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Revised: 05/28/2022] [Accepted: 06/08/2022] [Indexed: 06/15/2023]
Abstract
Mutations are an important origin of antibiotic resistance in bacteria. While there is increasing evidence showing promoted resistance mutations by environmental stresses, no retrospective research has yet been conducted on this phenomenon and its mechanisms. Herein, we summarized the phenomena of stress-elevated resistance mutations in bacteria, generalized the regulatory mechanisms and discussed the environmental and human health implications. It is shown that both chemical pollutants, such as antibiotics and other pharmaceuticals, biocides, metals, nanoparticles and disinfection byproducts, and non-chemical stressors, such as ultraviolet radiation, electrical stimulation and starvation, are capable of elevating resistance mutations in bacteria. Notably, resistance mutations are more likely to occur under sublethal or subinhibitory levels of these stresses, suggesting a considerable environmental concern. Further, mechanisms for stress-induced mutations are summarized in several points, namely oxidative stress, SOS response, DNA replication and repair systems, RpoS regulon and biofilm formation, all of which are readily provoked by common environmental stresses. Given bacteria in the environment are confronted with a variety of unfavorable conditions, we propose that the stress-elevated resistance mutations are a universal phenomenon in the environment and represent a nonnegligible risk factor for ecosystems and human health. The present review identifies a need for taking into account the pollutants' ability to elevate resistance mutations when assessing their environmental and human health risks and highlights the necessity of including resistance mutations as a target to prevent antibiotic resistance evolution.
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Affiliation(s)
- Dali Wang
- Guangdong Provincial Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou, 511443, China
| | - Qing Ning
- Guangdong Provincial Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou, 511443, China
| | | | - Meng Zhang
- Shenzhen Dapeng New District Center for Disease Control and Prevention, Shenzhen, 518000, China
| | - Jing You
- Guangdong Provincial Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou, 511443, China.
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