1
|
Reva ON, La Cono V, Crisafi F, Smedile F, Mudaliyar M, Ghosal D, Giuliano L, Krupovic M, Yakimov MM. Interplay of intracellular and trans-cellular DNA methylation in natural archaeal consortia. ENVIRONMENTAL MICROBIOLOGY REPORTS 2024; 16:e13258. [PMID: 38589217 PMCID: PMC11001535 DOI: 10.1111/1758-2229.13258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Accepted: 03/15/2024] [Indexed: 04/10/2024]
Abstract
DNA methylation serves a variety of functions across all life domains. In this study, we investigated archaeal methylomics within a tripartite xylanolytic halophilic consortium. This consortium includes Haloferax lucertense SVX82, Halorhabdus sp. SVX81, and an ectosymbiotic Candidatus Nanohalococcus occultus SVXNc, a nano-sized archaeon from the DPANN superphylum. We utilized PacBio SMRT and Illumina cDNA sequencing to analyse samples from consortia of different compositions for methylomics and transcriptomics. Endogenous cTAG methylation, typical of Haloferax, was accompanied in this strain by methylation at four other motifs, including GDGcHC methylation, which is specific to the ectosymbiont. Our analysis of the distribution of methylated and unmethylated motifs suggests that autochthonous cTAG methylation may influence gene regulation. The frequency of GRAGAaG methylation increased in highly expressed genes, while CcTTG and GTCGaGG methylation could be linked to restriction-modification (RM) activity. Generally, the RM activity might have been reduced during the evolution of this archaeon to balance the protection of cells from intruders, the reduction of DNA damage due to self-restriction in stressful environments, and the benefits of DNA exchange under extreme conditions. Our methylomics, transcriptomics and complementary electron cryotomography (cryo-ET) data suggest that the nanohaloarchaeon exports its methyltransferase to methylate the Haloferax genome, unveiling a new aspect of the interaction between the symbiont and its host.
Collapse
Affiliation(s)
- Oleg N. Reva
- Department of Biochemistry, Genetics and Microbiology, Centre for Bioinformatics and Computational BiologyUniversity of PretoriaPretoriaSouth Africa
| | - Violetta La Cono
- Extreme Microbiology, Biotechnology and Astrobiology GroupInstitute of Polar Sciences, ISP‐CNRMessinaItaly
| | - Francesca Crisafi
- Extreme Microbiology, Biotechnology and Astrobiology GroupInstitute of Polar Sciences, ISP‐CNRMessinaItaly
| | - Francesco Smedile
- Extreme Microbiology, Biotechnology and Astrobiology GroupInstitute of Polar Sciences, ISP‐CNRMessinaItaly
| | - Manasi Mudaliyar
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology InstituteThe University of MelbourneMelbourneVictoriaAustralia
- ARC Centre for Cryo‐electron Microscopy of Membrane Proteins, Bio21 Molecular Science and Biotechnology InstituteUniversity of MelbourneParkvilleVictoriaAustralia
| | - Debnath Ghosal
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology InstituteThe University of MelbourneMelbourneVictoriaAustralia
- ARC Centre for Cryo‐electron Microscopy of Membrane Proteins, Bio21 Molecular Science and Biotechnology InstituteUniversity of MelbourneParkvilleVictoriaAustralia
| | | | - Mart Krupovic
- Istitut Pasteur, Archaeal Virology UnitUniversité Paris CitéParisFrance
| | - Michail M. Yakimov
- Extreme Microbiology, Biotechnology and Astrobiology GroupInstitute of Polar Sciences, ISP‐CNRMessinaItaly
| |
Collapse
|
2
|
Tripathi S, Voogdt CGP, Bassler SO, Anderson M, Huang PH, Sakenova N, Capraz T, Jain S, Koumoutsi A, Bravo AM, Trotter V, Zimmerman M, Sonnenburg JL, Buie C, Typas A, Deutschbauer AM, Shiver AL, Huang KC. Randomly barcoded transposon mutant libraries for gut commensals I: Strategies for efficient library construction. Cell Rep 2024; 43:113517. [PMID: 38142397 DOI: 10.1016/j.celrep.2023.113517] [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: 07/27/2023] [Revised: 10/22/2023] [Accepted: 11/14/2023] [Indexed: 12/26/2023] Open
Abstract
Randomly barcoded transposon mutant libraries are powerful tools for studying gene function and organization, assessing gene essentiality and pathways, discovering potential therapeutic targets, and understanding the physiology of gut bacteria and their interactions with the host. However, construction of high-quality libraries with uniform representation can be challenging. In this review, we survey various strategies for barcoded library construction, including transposition systems, methods of transposon delivery, optimal library size, and transconjugant selection schemes. We discuss the advantages and limitations of each approach, as well as factors to consider when selecting a strategy. In addition, we highlight experimental and computational advances in arraying condensed libraries from mutant pools. We focus on examples of successful library construction in gut bacteria and their application to gene function studies and drug discovery. Given the need for understanding gene function and organization in gut bacteria, we provide a comprehensive guide for researchers to construct randomly barcoded transposon mutant libraries.
Collapse
Affiliation(s)
- Surya Tripathi
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Carlos Geert Pieter Voogdt
- Genome Biology Unit, EMBL Heidelberg, Meyerhofstraße 1, 69117 Heidelberg, Germany; Structural and Computational Biology Unit, EMBL Meyerhofstraße 1, 69117 Heidelberg, Germany
| | - Stefan Oliver Bassler
- Genome Biology Unit, EMBL Heidelberg, Meyerhofstraße 1, 69117 Heidelberg, Germany; Faculty of Biosciences, Heidelberg University, Grabengasse 1, 69117 Heidelberg, Germany
| | - Mary Anderson
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Po-Hsun Huang
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Nazgul Sakenova
- Genome Biology Unit, EMBL Heidelberg, Meyerhofstraße 1, 69117 Heidelberg, Germany
| | - Tümay Capraz
- Genome Biology Unit, EMBL Heidelberg, Meyerhofstraße 1, 69117 Heidelberg, Germany; Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Sunit Jain
- Chan Zuckerberg Biohub, San Francisco, CA 94158, USA
| | - Alexandra Koumoutsi
- Genome Biology Unit, EMBL Heidelberg, Meyerhofstraße 1, 69117 Heidelberg, Germany
| | - Afonso Martins Bravo
- Department of Fundamental Microbiology, University of Lausanne, 1015 Lausanne, Switzerland
| | - Valentine Trotter
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Michael Zimmerman
- Structural and Computational Biology Unit, EMBL Meyerhofstraße 1, 69117 Heidelberg, Germany
| | - Justin L Sonnenburg
- Chan Zuckerberg Biohub, San Francisco, CA 94158, USA; Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Cullen Buie
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Athanasios Typas
- Genome Biology Unit, EMBL Heidelberg, Meyerhofstraße 1, 69117 Heidelberg, Germany; Structural and Computational Biology Unit, EMBL Meyerhofstraße 1, 69117 Heidelberg, Germany.
| | - Adam M Deutschbauer
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
| | - Anthony L Shiver
- Department of Bioengineering, Stanford University, Stanford, CA 94305, USA.
| | - Kerwyn Casey Huang
- Chan Zuckerberg Biohub, San Francisco, CA 94158, USA; Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Bioengineering, Stanford University, Stanford, CA 94305, USA.
| |
Collapse
|
3
|
Abstract
Methanogenic archaea are the only organisms that produce CH4 as part of their energy-generating metabolism. They are ubiquitous in oxidant-depleted, anoxic environments such as aquatic sediments, anaerobic digesters, inundated agricultural fields, the rumen of cattle, and the hindgut of termites, where they catalyze the terminal reactions in the degradation of organic matter. Methanogenesis is the only metabolism that is restricted to members of the domain Archaea. Here, we discuss the importance of model organisms in the history of methanogen research, including their role in the discovery of the archaea and in the biochemical and genetic characterization of methanogenesis. We also discuss outstanding questions in the field and newly emerging model systems that will expand our understanding of this uniquely archaeal metabolism.
Collapse
Affiliation(s)
- Kyle C. Costa
- Department of Plant and Microbial Biology, University of Minnesota, St. Paul, Minnesota, USA
| | | |
Collapse
|
4
|
Ryan ME, Damke PP, Shaffer CL. DNA Transport through the Dynamic Type IV Secretion System. Infect Immun 2023; 91:e0043622. [PMID: 37338415 PMCID: PMC10353360 DOI: 10.1128/iai.00436-22] [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] [Indexed: 06/21/2023] Open
Abstract
The versatile type IV secretion system (T4SS) nanomachine plays a pivotal role in bacterial pathogenesis and the propagation of antibiotic resistance determinants throughout microbial populations. In addition to paradigmatic DNA conjugation machineries, diverse T4SSs enable the delivery of multifarious effector proteins to target prokaryotic and eukaryotic cells, mediate DNA export and uptake from the extracellular milieu, and in rare examples, facilitate transkingdom DNA translocation. Recent advances have identified new mechanisms underlying unilateral nucleic acid transport through the T4SS apparatus, highlighting both functional plasticity and evolutionary adaptations that enable novel capabilities. In this review, we describe the molecular mechanisms underscoring DNA translocation through diverse T4SS machineries, emphasizing the architectural features that implement DNA exchange across the bacterial membrane and license transverse DNA release across kingdom boundaries. We further detail how recent studies have addressed outstanding questions surrounding the mechanisms by which nanomachine architectures and substrate recruitment strategies contribute to T4SS functional diversity.
Collapse
Affiliation(s)
- Mackenzie E. Ryan
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky College of Medicine, Lexington, Kentucky, USA
| | - Prashant P. Damke
- Department of Veterinary Sciences, University of Kentucky College of Agriculture, Lexington, Kentucky, USA
| | - Carrie L. Shaffer
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky College of Medicine, Lexington, Kentucky, USA
- Department of Veterinary Sciences, University of Kentucky College of Agriculture, Lexington, Kentucky, USA
- Department of Pharmaceutical Sciences, University of Kentucky College of Pharmacy, Lexington, Kentucky, USA
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, Kentucky, USA
| |
Collapse
|
5
|
Li X, Bao N, Yan Z, Yuan XZ, Wang SG, Xia PF. Degradation of Antibiotic Resistance Genes by VADER with CRISPR-Cas Immunity. Appl Environ Microbiol 2023; 89:e0005323. [PMID: 36975789 PMCID: PMC10132114 DOI: 10.1128/aem.00053-23] [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: 01/12/2023] [Accepted: 03/03/2023] [Indexed: 03/29/2023] Open
Abstract
The evolution and dissemination of antibiotic resistance genes (ARGs) are prompting severe health and environmental issues. While environmental processes, e.g., biological wastewater treatment, are key barriers to prevent the spread of ARGs, they are often sources of ARGs at the same time, requiring upgraded biotechnology. Here, we present VADER, a synthetic biology system for the degradation of ARGs based on CRISPR-Cas immunity, an archaeal and bacterial immune system for eliminating invading foreign DNAs, to be implemented for wastewater treatment processes. Navigated by programmable guide RNAs, VADER targets and degrades ARGs depending on their DNA sequences, and by employing an artificial conjugation machinery, IncP, it can be delivered via conjugation. The system was evaluated by degrading plasmid-borne ARGs in Escherichia coli and further demonstrated via the elimination of ARGs on the environmentally relevant RP4 plasmid in Pseudomonas aeruginosa. Next, a prototype conjugation reactor at a 10-mL scale was devised, and 100% of the target ARG was eliminated in the transconjugants receiving VADER, giving a proof of principle for the implementation of VADER in bioprocesses. By generating a nexus of synthetic biology and environmental biotechnology, we believe that our work is not only an enterprise for tackling ARG problems but also a potential solution for managing undesired genetic materials in general in the future. IMPORTANCE Antibiotic resistance has been causing severe health problems and has led to millions of deaths in recent years. Environmental processes, especially those of the wastewater treatment sector, are an important barrier to the spread of antibiotic resistance from the pharmaceutical industry, hospitals, or civil sewage. However, they have been identified as a nonnegligible source of antibiotic resistance at the same time, as antibiotic resistance with its main cause, antibiotic resistance genes (ARGs), may accumulate in biological treatment units. Here, we transplanted the CRISPR-Cas system, an immune system via programmable DNA cleavage, to tackle the antibiotic resistance problem raised in wastewater treatment processes, and we propose a new sector specialized in ARG removal with a conjugation reactor to implement the CRISPR-Cas system. Our study provides a new angle for resolving public health issues via the implementation of synthetic biology in environmental contexts at the process level.
Collapse
Affiliation(s)
- Xin Li
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, China
| | - Nan Bao
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, China
| | - Zhen Yan
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, China
| | - Xian-Zheng Yuan
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, China
- Sino-French Research Institute for Ecology and Environment, Shandong University, Qingdao, China
| | - Shu-Guang Wang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, China
- Sino-French Research Institute for Ecology and Environment, Shandong University, Qingdao, China
| | - Peng-Fei Xia
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, China
| |
Collapse
|
6
|
Hwang Y, Roux S, Coclet C, Krause SJE, Girguis PR. Viruses interact with hosts that span distantly related microbial domains in dense hydrothermal mats. Nat Microbiol 2023; 8:946-957. [PMID: 37024618 PMCID: PMC10159854 DOI: 10.1038/s41564-023-01347-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 02/25/2023] [Indexed: 04/08/2023]
Abstract
Many microbes in nature reside in dense, metabolically interdependent communities. We investigated the nature and extent of microbe-virus interactions in relation to microbial density and syntrophy by examining microbe-virus interactions in a biomass dense, deep-sea hydrothermal mat. Using metagenomic sequencing, we find numerous instances where phylogenetically distant (up to domain level) microbes encode CRISPR-based immunity against the same viruses in the mat. Evidence of viral interactions with hosts cross-cutting microbial domains is particularly striking between known syntrophic partners, for example those engaged in anaerobic methanotrophy. These patterns are corroborated by proximity-ligation-based (Hi-C) inference. Surveys of public datasets reveal additional viruses interacting with hosts across domains in diverse ecosystems known to harbour syntrophic biofilms. We propose that the entry of viral particles and/or DNA to non-primary host cells may be a common phenomenon in densely populated ecosystems, with eco-evolutionary implications for syntrophic microbes and CRISPR-mediated inter-population augmentation of resilience against viruses.
Collapse
Affiliation(s)
- Yunha Hwang
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA.
| | - Simon Roux
- DOE (Department of Energy) Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Clément Coclet
- DOE (Department of Energy) Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Sebastian J E Krause
- Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, CA, USA
| | - Peter R Girguis
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA.
| |
Collapse
|
7
|
Li J, Akinyemi TS, Shao N, Chen C, Dong X, Liu Y, Whitman WB. Genetic and Metabolic Engineering of Methanococcus spp. CURRENT RESEARCH IN BIOTECHNOLOGY 2022. [DOI: 10.1016/j.crbiot.2022.11.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
|
8
|
Gophna U, Altman-Price N. Horizontal Gene Transfer in Archaea-From Mechanisms to Genome Evolution. Annu Rev Microbiol 2022; 76:481-502. [PMID: 35667126 DOI: 10.1146/annurev-micro-040820-124627] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Archaea remains the least-studied and least-characterized domain of life despite its significance not just to the ecology of our planet but also to the evolution of eukaryotes. It is therefore unsurprising that research into horizontal gene transfer (HGT) in archaea has lagged behind that of bacteria. Indeed, several archaeal lineages may owe their very existence to large-scale HGT events, and thus understanding both the molecular mechanisms and the evolutionary impact of HGT in archaea is highly important. Furthermore, some mechanisms of gene exchange, such as plasmids that transmit themselves via membrane vesicles and the formation of cytoplasmic bridges that allows transfer of both chromosomal and plasmid DNA, may be archaea specific. This review summarizes what we know about HGT in archaea, and the barriers that restrict it, highlighting exciting recent discoveries and pointing out opportunities for future research. Expected final online publication date for the Annual Review of Microbiology, Volume 76 is September 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
Collapse
Affiliation(s)
- Uri Gophna
- The Shmunis School of Biomedicine and Cancer Research, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel; ,
| | - Neta Altman-Price
- The Shmunis School of Biomedicine and Cancer Research, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel; , .,Department of Natural and Life Sciences, The Open University of Israel, Raanana, Israel
| |
Collapse
|
9
|
Fink C, Angenent LT, Molitor B. An Interdomain Conjugation Protocol for Plasmid-DNA Transfer into Methanothermobacter thermautotrophicus ΔH. Methods Mol Biol 2022; 2522:119-133. [PMID: 36125746 DOI: 10.1007/978-1-0716-2445-6_7] [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: 06/15/2023]
Abstract
Methanogenic archaea of the order Methanobacteriales are widespread in anaerobic environments and play pivotal roles in microbial communities. The family of Methanobacteriaceae encompasses mesophilic and thermophilic hydrogenotrophic species. Mesophilic species are found in various natural and anthropogenic environments (e.g., are associated with the microbiome in animals and humans). Thermophilic species can be found in thermally active bogs and warm sulfuric springs, but also in anthropogenic environments, such as wastewater treatment plants and anaerobic digesters. Recently, genetic tools for Methanothermobacter thermautotrophicus ΔH, as the first representative of this order of methanogenic archaea, were successfully implemented. This protocol describes the methods for interdomain conjugational DNA transfer from Escherichia coli to M. thermautotrophicus ΔH with shuttle-vector plasmid DNA, which allows the genetic manipulation of this microbe, and provides a basis for the development of further genetic methods for this and potentially other representatives of Methanobacteriales.
Collapse
Affiliation(s)
- Christian Fink
- Environmental Biotechnology Group, University of Tübingen, Tübingen, Germany
| | - Largus T Angenent
- Environmental Biotechnology Group, University of Tübingen, Tübingen, Germany
- Cluster of Excellence-Controlling Microbes to Fight Infections, University of Tübingen, Tübingen, Germany
- AG Angenent, Max Planck Institute for Biology Tübingen, Tübingen, Germany
| | - Bastian Molitor
- Environmental Biotechnology Group, University of Tübingen, Tübingen, Germany.
- Cluster of Excellence-Controlling Microbes to Fight Infections, University of Tübingen, Tübingen, Germany.
| |
Collapse
|
10
|
A Shuttle-Vector System Allows Heterologous Gene Expression in the Thermophilic Methanogen Methanothermobacter thermautotrophicus ΔH. mBio 2021; 12:e0276621. [PMID: 34809461 PMCID: PMC8609365 DOI: 10.1128/mbio.02766-21] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Thermophilic Methanothermobacter spp. are used as model microbes to study the physiology and biochemistry of the conversion of molecular hydrogen and carbon dioxide into methane (i.e., hydrogenotrophic methanogenesis). Yet, a genetic system for these model microbes was missing despite intensive work for four decades. Here, we report the successful implementation of genetic tools for Methanothermobacter thermautotrophicus ΔH. We developed shuttle vectors that replicated in Escherichia coli and M. thermautotrophicus ΔH. For M. thermautotrophicus ΔH, a thermostable neomycin resistance cassette served as the selectable marker for positive selection with neomycin, and the cryptic plasmid pME2001 from Methanothermobacter marburgensis served as the replicon. The shuttle-vector DNA was transferred from E. coli into M. thermautotrophicus ΔH via interdomain conjugation. After the successful validation of DNA transfer and positive selection in M. thermautotrophicus ΔH, we demonstrated heterologous gene expression of a thermostable β-galactosidase-encoding gene (bgaB) from Geobacillus stearothermophilus under the expression control of four distinct synthetic and native promoters. In quantitative in-vitro enzyme activity assay, we found significantly different β-galactosidase activity with these distinct promoters. With a formate dehydrogenase operon-encoding shuttle vector, we allowed growth of M. thermautotrophicus ΔH on formate as the sole growth substrate, while this was not possible for the empty-vector control.
Collapse
|
11
|
Zoolkefli FIRM, Moriguchi K, Cho Y, Kiyokawa K, Yamamoto S, Suzuki K. Isolation and Analysis of Donor Chromosomal Genes Whose Deficiency Is Responsible for Accelerating Bacterial and Trans-Kingdom Conjugations by IncP1 T4SS Machinery. Front Microbiol 2021; 12:620535. [PMID: 34093458 PMCID: PMC8174662 DOI: 10.3389/fmicb.2021.620535] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 04/06/2021] [Indexed: 11/13/2022] Open
Abstract
Conjugal transfer is a major driving force of genetic exchange in eubacteria, and the system in IncP1-type broad-host-range plasmids transfers DNA even to eukaryotes and archaea in a process known as trans-kingdom conjugation (TKC). Although conjugation factors encoded on plasmids have been extensively analyzed, those on the donor chromosome have not. To identify the potential conjugation factor(s), a genome-wide survey on a comprehensive collection of Escherichia coli gene knockout mutants (Keio collection) as donors to Saccharomyces cerevisiae recipients was performed using a conjugal transfer system mediated by the type IV secretion system (T4SS) of the IncP1α plasmid. Out of 3,884 mutants, three mutants (ΔfrmR, ΔsufA, and ΔiscA) were isolated, which showed an increase by one order of magnitude in both E. coli-E. coli and E. coli-yeast conjugations without an increase in the mRNA accumulation level for the conjugation related genes examined. The double-knockout mutants for these genes (ΔfrmRΔsufA and ΔiscAΔfrmR) did not show synergistic effects on the conjugation efficiency, suggesting that these factors affect a common step in the conjugation machinery. The three mutants demonstrated increased conjugation efficiency in IncP1β-type but not in IncN- and IncW-type broad-host-range plasmid transfers, and the homologous gene knockout mutants against the three genes in Agrobacterium tumefaciens also showed increased TKC efficiency. These results suggest the existence of a specific regulatory system in IncP1 plasmids that enables the control of conjugation efficiency in different hosts, which could be utilized for the development of donor strains as gene introduction tools into bacteria, eukaryotes, and archaea.
Collapse
Affiliation(s)
| | - Kazuki Moriguchi
- Department of Biological Science, Graduate School of Science, Hiroshima University, Higashihiroshima, Japan.,Program of Basic Biology, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
| | - Yunjae Cho
- Department of Biological Science, Faculty of Science, Hiroshima University, Higashihiroshima, Japan
| | - Kazuya Kiyokawa
- Program of Basic Biology, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
| | - Shinji Yamamoto
- Department of Biological Science, Graduate School of Science, Hiroshima University, Higashihiroshima, Japan
| | - Katsunori Suzuki
- Department of Biological Science, Graduate School of Science, Hiroshima University, Higashihiroshima, Japan.,Program of Basic Biology, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
| |
Collapse
|
12
|
Virolle C, Goldlust K, Djermoun S, Bigot S, Lesterlin C. Plasmid Transfer by Conjugation in Gram-Negative Bacteria: From the Cellular to the Community Level. Genes (Basel) 2020; 11:genes11111239. [PMID: 33105635 PMCID: PMC7690428 DOI: 10.3390/genes11111239] [Citation(s) in RCA: 96] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 10/15/2020] [Accepted: 10/20/2020] [Indexed: 02/06/2023] Open
Abstract
Bacterial conjugation, also referred to as bacterial sex, is a major horizontal gene transfer mechanism through which DNA is transferred from a donor to a recipient bacterium by direct contact. Conjugation is universally conserved among bacteria and occurs in a wide range of environments (soil, plant surfaces, water, sewage, biofilms, and host-associated bacterial communities). Within these habitats, conjugation drives the rapid evolution and adaptation of bacterial strains by mediating the propagation of various metabolic properties, including symbiotic lifestyle, virulence, biofilm formation, resistance to heavy metals, and, most importantly, resistance to antibiotics. These properties make conjugation a fundamentally important process, and it is thus the focus of extensive study. Here, we review the key steps of plasmid transfer by conjugation in Gram-negative bacteria, by following the life cycle of the F factor during its transfer from the donor to the recipient cell. We also discuss our current knowledge of the extent and impact of conjugation within an environmentally and clinically relevant bacterial habitat, bacterial biofilms.
Collapse
|
13
|
Type IV-Like Pili Facilitate Transformation in Naturally Competent Archaea. J Bacteriol 2020; 202:JB.00355-20. [PMID: 32817089 DOI: 10.1128/jb.00355-20] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 08/07/2020] [Indexed: 12/19/2022] Open
Abstract
Naturally competent organisms are capable of DNA uptake directly from the environment through the process of transformation. Despite the importance of transformation to microbial evolution, DNA uptake remains poorly characterized outside of the bacterial domain. Here, we identify the pilus as a necessary component of the transformation machinery in archaea. We describe two naturally competent organisms, Methanococcus maripaludis and Methanoculleus thermophilus In M. maripaludis, replicative vectors were transferred with an average efficiency of 2.4 × 103 transformants μg-1 DNA. In M. thermophilus, integrative vectors were transferred with an average efficiency of 2.7 × 103 transformants μg-1 DNA. Additionally, natural transformation of M. thermophilus could be used to introduce chromosomal mutations. To our knowledge, this is the first demonstration of a method to introduce targeted mutations in a member of the order Methanomicrobiales For both organisms, mutants lacking structural components of the type IV-like pilus filament were defective for DNA uptake, demonstrating the importance of pili for natural transformation. Interestingly, competence could be induced in a noncompetent strain of M. maripaludis by expressing pilin genes from a replicative vector. These results expand the known natural competence pili to include examples from the archaeal domain and highlight the importance of pili for DNA uptake in diverse microbial organisms.IMPORTANCE Microbial organisms adapt and evolve by acquiring new genetic material through horizontal gene transfer. One way that this occurs is natural transformation, the direct uptake and genomic incorporation of environmental DNA by competent organisms. Archaea represent up to a third of the biodiversity on Earth, yet little is known about transformation in these organisms. Here, we provide the first characterization of a component of the archaeal DNA uptake machinery. We show that the type IV-like pilus is essential for natural transformation in two archaeal species. This suggests that pili are important for transformation across the tree of life and further expands our understanding of gene flow in archaea.
Collapse
|
14
|
Moriguchi K, Zoolkefli FIRM, Abe M, Kiyokawa K, Yamamoto S, Suzuki K. Targeting Antibiotic Resistance Genes Is a Better Approach to Block Acquisition of Antibiotic Resistance Than Blocking Conjugal Transfer by Recipient Cells: A Genome-Wide Screening in Escherichia coli. Front Microbiol 2020; 10:2939. [PMID: 31969865 PMCID: PMC6960129 DOI: 10.3389/fmicb.2019.02939] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Accepted: 12/06/2019] [Indexed: 11/21/2022] Open
Abstract
The conjugal transfer is a major driving force in the spread of antibiotic resistance genes. Nevertheless, an effective approach has not yet been developed to target conjugal transfer to prevent the acquisition of antibiotic resistance by this mechanism. This study aimed to identify potential targets for plasmid transfer blockade by isolating mutants defective in the completion of the acquisition of antibiotic resistance via conjugal transfer. We performed genome-wide screening by combining an IncP1α-type broad host range plasmid conjugation system with a comprehensive collection of Escherichia coli gene knockout mutants (Keio collection; 3884 mutants). We followed a six-step screening procedure to identify the mutants showing conjugation deficiency precisely. No mutants defective in the conjugal transfer were isolated, strongly suggesting that E. coli cannot escape from being a recipient organism for P1α plasmid transfer. However, several mutants with low viability were identified, as well as mutants defective in establishing resistance to chloramphenicol, which was used for transconjugant selection. These results suggest that developing drugs capable of inhibiting the establishment of antibiotic resistance is a better approach than attempting to prevent the conjugal transfer to block the spread of antibiotic resistance genes. Our screening system based on the IncP1α-type plasmid transfer can be extended to isolation of target genes for other drugs. This study could be the foundation for further research to understand its underlying molecular mechanism through functional analysis of the identified genes.
Collapse
Affiliation(s)
- Kazuki Moriguchi
- Program of Basic Biology, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan.,Department of Biological Science, Graduate School of Science, Hiroshima University, Higashihiroshima, Japan
| | | | - Masanobu Abe
- Division for Health Service Promotion, University of Tokyo, Tokyo, Japan
| | - Kazuya Kiyokawa
- Program of Basic Biology, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan.,Department of Biological Science, Graduate School of Science, Hiroshima University, Higashihiroshima, Japan
| | - Shinji Yamamoto
- Department of Biological Science, Graduate School of Science, Hiroshima University, Higashihiroshima, Japan
| | - Katsunori Suzuki
- Program of Basic Biology, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan.,Department of Biological Science, Graduate School of Science, Hiroshima University, Higashihiroshima, Japan
| |
Collapse
|
15
|
Takahashi TS, Da Cunha V, Krupovic M, Mayer C, Forterre P, Gadelle D. Expanding the type IIB DNA topoisomerase family: identification of new topoisomerase and topoisomerase-like proteins in mobile genetic elements. NAR Genom Bioinform 2019; 2:lqz021. [PMID: 33575570 PMCID: PMC7671362 DOI: 10.1093/nargab/lqz021] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 11/12/2019] [Accepted: 12/06/2019] [Indexed: 12/13/2022] Open
Abstract
The control of DNA topology by DNA topoisomerases is essential for virtually all DNA transactions in the cell. These enzymes, present in every organism, exist as several non-homologous families. We previously identified a small group of atypical type IIB topoisomerases, called Topo VIII, mainly encoded by plasmids. Here, taking advantage of the rapid expansion of sequence databases, we identified new putative Topo VIII homologs. Our analyses confirm the exclusivity of the corresponding genes to mobile genetic elements (MGE) and extend their distribution to nine different bacterial phyla and one archaeal superphylum. Notably, we discovered another subfamily of topoisomerases, dubbed ‘Mini-A’, including distant homologs of type IIB topoisomerases and encoded by extrachromosomal and integrated bacterial and archaeal viruses. Interestingly, a short, functionally uncharacterized motif at the C-terminal extremity of type IIB topoisomerases appears sufficient to discriminate between Mini-A, Topo VI and Topo VIII subfamilies. This motif could be a key element for understanding the differences between the three subfamilies. Collectively, this work leads to an updated model for the origin and evolution of the type IIB topoisomerase family and raises questions regarding the role of topoisomerases during replication of MGE in bacteria and archaea.
Collapse
Affiliation(s)
- Tomio S Takahashi
- Institut de Biologie Intégrative de la Cellule, CNRS, Université Paris-Saclay, 91198 Gif sur Yvette Cedex, France.,Unité de Microbiologie Structurale, Institut Pasteur, CNRS, F-75015 Paris, France
| | - Violette Da Cunha
- Institut de Biologie Intégrative de la Cellule, CNRS, Université Paris-Saclay, 91198 Gif sur Yvette Cedex, France
| | - Mart Krupovic
- Institut Pasteur, Archaeal Virology Unit, Department of Microbiology, 75015 Paris, France
| | - Claudine Mayer
- Unité de Microbiologie Structurale, Institut Pasteur, CNRS, F-75015 Paris, France.,Université de Paris, Paris Diderot, F-75013 Paris, France
| | - Patrick Forterre
- Institut de Biologie Intégrative de la Cellule, CNRS, Université Paris-Saclay, 91198 Gif sur Yvette Cedex, France.,Institut Pasteur, F-75015 Paris, France
| | - Danièle Gadelle
- Institut de Biologie Intégrative de la Cellule, CNRS, Université Paris-Saclay, 91198 Gif sur Yvette Cedex, France
| |
Collapse
|
16
|
Freed E, Fenster J, Smolinski SL, Walker J, Henard CA, Gill R, Eckert CA. Building a genome engineering toolbox in nonmodel prokaryotic microbes. Biotechnol Bioeng 2018; 115:2120-2138. [PMID: 29750332 DOI: 10.1002/bit.26727] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Revised: 04/02/2018] [Accepted: 03/10/2018] [Indexed: 12/26/2022]
Abstract
The realization of a sustainable bioeconomy requires our ability to understand and engineer complex design principles for the development of platform organisms capable of efficient conversion of cheap and sustainable feedstocks (e.g., sunlight, CO2 , and nonfood biomass) into biofuels and bioproducts at sufficient titers and costs. For model microbes, such as Escherichia coli, advances in DNA reading and writing technologies are driving the adoption of new paradigms for engineering biological systems. Unfortunately, microbes with properties of interest for the utilization of cheap and renewable feedstocks, such as photosynthesis, autotrophic growth, and cellulose degradation, have very few, if any, genetic tools for metabolic engineering. Therefore, it is important to develop "design rules" for building a genetic toolbox for novel microbes. Here, we present an overview of our current understanding of these rules for the genetic manipulation of prokaryotic microbes and the available genetic tools to expand our ability to genetically engineer nonmodel systems.
Collapse
Affiliation(s)
- Emily Freed
- National Renewable Energy Laboratory, Biosciences Center, Golden, CO.,Renewable and Sustainable Energy Institute, University of Colorado, Boulder, CO
| | - Jacob Fenster
- Renewable and Sustainable Energy Institute, University of Colorado, Boulder, CO.,Chemical and Biological Engineering, University of Colorado, Boulder, CO
| | | | - Julie Walker
- Renewable and Sustainable Energy Institute, University of Colorado, Boulder, CO
| | - Calvin A Henard
- National Renewable Energy Laboratory, National Bioenergy Center, Golden, CO
| | - Ryan Gill
- National Renewable Energy Laboratory, Biosciences Center, Golden, CO.,Renewable and Sustainable Energy Institute, University of Colorado, Boulder, CO.,Chemical and Biological Engineering, University of Colorado, Boulder, CO
| | - Carrie A Eckert
- National Renewable Energy Laboratory, Biosciences Center, Golden, CO.,Renewable and Sustainable Energy Institute, University of Colorado, Boulder, CO
| |
Collapse
|
17
|
Shapiro JA. Living Organisms Author Their Read-Write Genomes in Evolution. BIOLOGY 2017; 6:E42. [PMID: 29211049 PMCID: PMC5745447 DOI: 10.3390/biology6040042] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 11/17/2017] [Accepted: 11/28/2017] [Indexed: 12/18/2022]
Abstract
Evolutionary variations generating phenotypic adaptations and novel taxa resulted from complex cellular activities altering genome content and expression: (i) Symbiogenetic cell mergers producing the mitochondrion-bearing ancestor of eukaryotes and chloroplast-bearing ancestors of photosynthetic eukaryotes; (ii) interspecific hybridizations and genome doublings generating new species and adaptive radiations of higher plants and animals; and, (iii) interspecific horizontal DNA transfer encoding virtually all of the cellular functions between organisms and their viruses in all domains of life. Consequently, assuming that evolutionary processes occur in isolated genomes of individual species has become an unrealistic abstraction. Adaptive variations also involved natural genetic engineering of mobile DNA elements to rewire regulatory networks. In the most highly evolved organisms, biological complexity scales with "non-coding" DNA content more closely than with protein-coding capacity. Coincidentally, we have learned how so-called "non-coding" RNAs that are rich in repetitive mobile DNA sequences are key regulators of complex phenotypes. Both biotic and abiotic ecological challenges serve as triggers for episodes of elevated genome change. The intersections of cell activities, biosphere interactions, horizontal DNA transfers, and non-random Read-Write genome modifications by natural genetic engineering provide a rich molecular and biological foundation for understanding how ecological disruptions can stimulate productive, often abrupt, evolutionary transformations.
Collapse
Affiliation(s)
- James A Shapiro
- Department of Biochemistry and Molecular Biology, University of Chicago GCIS W123B, 979 E. 57th Street, Chicago, IL 60637, USA.
| |
Collapse
|
18
|
Shapiro JA. Nothing in Evolution Makes Sense Except in the Light of Genomics: Read-Write Genome Evolution as an Active Biological Process. BIOLOGY 2016; 5:E27. [PMID: 27338490 PMCID: PMC4929541 DOI: 10.3390/biology5020027] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Revised: 05/20/2016] [Accepted: 06/02/2016] [Indexed: 01/15/2023]
Abstract
The 21st century genomics-based analysis of evolutionary variation reveals a number of novel features impossible to predict when Dobzhansky and other evolutionary biologists formulated the neo-Darwinian Modern Synthesis in the middle of the last century. These include three distinct realms of cell evolution; symbiogenetic fusions forming eukaryotic cells with multiple genome compartments; horizontal organelle, virus and DNA transfers; functional organization of proteins as systems of interacting domains subject to rapid evolution by exon shuffling and exonization; distributed genome networks integrated by mobile repetitive regulatory signals; and regulation of multicellular development by non-coding lncRNAs containing repetitive sequence components. Rather than single gene traits, all phenotypes involve coordinated activity by multiple interacting cell molecules. Genomes contain abundant and functional repetitive components in addition to the unique coding sequences envisaged in the early days of molecular biology. Combinatorial coding, plus the biochemical abilities cells possess to rearrange DNA molecules, constitute a powerful toolbox for adaptive genome rewriting. That is, cells possess "Read-Write Genomes" they alter by numerous biochemical processes capable of rapidly restructuring cellular DNA molecules. Rather than viewing genome evolution as a series of accidental modifications, we can now study it as a complex biological process of active self-modification.
Collapse
Affiliation(s)
- James A Shapiro
- Department of Biochemistry and Molecular Biology, University of Chicago, GCIS W123B, 979 E. 57th Street, Chicago, IL 60637, USA.
| |
Collapse
|
19
|
Abstract
Many plasmids have been described in Euryarchaeota, one of the three major archaeal phyla, most of them in salt-loving haloarchaea and hyperthermophilic Thermococcales. These plasmids resemble bacterial plasmids in terms of size (from small plasmids encoding only one gene up to large megaplasmids) and replication mechanisms (rolling circle or theta). Some of them are related to viral genomes and form a more or less continuous sequence space including many integrated elements. Plasmids from Euryarchaeota have been useful for designing efficient genetic tools for these microorganisms. In addition, they have also been used to probe the topological state of plasmids in species with or without DNA gyrase and/or reverse gyrase. Plasmids from Euryarchaeota encode both DNA replication proteins recruited from their hosts and novel families of DNA replication proteins. Euryarchaeota form an interesting playground to test evolutionary hypotheses on the origin and evolution of viruses and plasmids, since a robust phylogeny is available for this phylum. Preliminary studies have shown that for different plasmid families, plasmids share a common gene pool and coevolve with their hosts. They are involved in gene transfer, mostly between plasmids and viruses present in closely related species, but rarely between cells from distantly related archaeal lineages. With few exceptions (e.g., plasmids carrying gas vesicle genes), most archaeal plasmids seem to be cryptic. Interestingly, plasmids and viral genomes have been detected in extracellular membrane vesicles produced by Thermococcales, suggesting that these vesicles could be involved in the transfer of viruses and plasmids between cells.
Collapse
|
20
|
Li X, Fu L, Li Z, Ma X, Xiao X, Xu J. Genetic tools for the piezophilic hyperthermophilic archaeon Pyrococcus yayanosii. Extremophiles 2014; 19:59-67. [PMID: 25391810 DOI: 10.1007/s00792-014-0705-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Accepted: 10/28/2014] [Indexed: 11/30/2022]
Abstract
The hyperthermophile Pyrococcus yayanosii CH1 is the only high-pressure-requiring microorganism obtained thus far within the archaea domain or among all non-psychrophiles in any domain. In this study, we developed a genetic manipulation system for P. yayanosii after first isolating a facultatively piezophilic derivative strain, designated P. yayanosii A1. The 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase gene was overexpressed in strain P. yayanosii A1 and was demonstrated to confer host cell resistance against simvastatin. Furthermore, using simvastatin as a selection marker, the endogenous pyrF of P. yayanosii A1 was disrupted through homologous recombination, thus generating the additional host strain P. yayanosii A2 (ΔpyrF). A markerless gene disruption vector was constructed by incorporating a pyrF-sim (R) cassette that enables the combined use of simvastatin resistance for positive selection and 5-FOA for counter selection. The utility of this versatile disruption system was demonstrated by deleting the carbon-nitrogen hydrolase of P. yayanosii strain A1. These results demonstrate that a variety of genetic tools are now in place to study unknown gene function and the molecular mechanisms of piezophilic adaptation in P. yayanosii.
Collapse
Affiliation(s)
- Xuegong Li
- Institute of Oceanology, Shanghai Jiao Tong University, Minhang Dongchuan Road 800, Shanghai, 200240, China
| | | | | | | | | | | |
Collapse
|
21
|
Costa KC, Leigh JA. Metabolic versatility in methanogens. Curr Opin Biotechnol 2014; 29:70-5. [DOI: 10.1016/j.copbio.2014.02.012] [Citation(s) in RCA: 91] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2013] [Revised: 02/14/2014] [Accepted: 02/18/2014] [Indexed: 10/25/2022]
|
22
|
Załuga J, Stragier P, Baeyen S, Haegeman A, Van Vaerenbergh J, Maes M, De Vos P. Comparative genome analysis of pathogenic and non-pathogenic Clavibacter strains reveals adaptations to their lifestyle. BMC Genomics 2014; 15:392. [PMID: 24885539 PMCID: PMC4059874 DOI: 10.1186/1471-2164-15-392] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Accepted: 05/09/2014] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND The genus Clavibacter harbors economically important plant pathogens infecting agricultural crops such as potato and tomato. Although the vast majority of Clavibacter strains are pathogenic, there is an increasing number of non-pathogenic isolates reported. Non-pathogenic Clavibacter strains isolated from tomato seeds are particularly problematic because they affect the current detection and identification tests for Clavibacter michiganensis subsp. michiganensis (Cmm), which is regulated with a zero tolerance in tomato seed. Their misidentification as pathogenic Cmm hampers a clear judgment on the seed quality and health. RESULTS To get more insight in the genetic features linked to the lifestyle of these bacteria, a whole-genome sequence of the tomato seed-borne non-pathogenic Clavibacter LMG 26808 was determined. To gain a better understanding of the molecular determinants of pathogenicity, the genome sequence of LMG 26808 was compared with that of the pathogenic Cmm strain (NCPPB 382). The comparative analysis revealed that LMG 26808 does not contain plasmids pCM1 and pCM2 and also lacks the majority of important virulence factors described so far for pathogenic Cmm. This explains its apparent non-pathogenic nature in tomato plants. Moreover, the genome analysis of LMG 26808 detected sequences from a plasmid originating from a member of Enterobacteriaceae/Klebsiella relative. Genes received that way and coding for antibiotic resistance may provide a competitive advantage for survival of LMG 26808 in its ecological niche. Genetically, LMG 26808 was the most similar to the pathogenic Cmm NCPPB 382 but contained more mobile genetic elements. The genome of this non-pathogenic Clavibacter strain contained also a high number of transporters and regulatory genes. CONCLUSIONS The genome sequence of the non-pathogenic Clavibacter strain LMG 26808 and the comparative analyses with other pathogenic Clavibacter strains provided a better understanding of the genetic bases of virulence and adaptation mechanisms present in the genus Clavibacter.
Collapse
Affiliation(s)
- Joanna Załuga
- />Laboratory of Microbiology, Department of Biochemistry and Microbiology, Ghent University, K.L. Ledeganckstraat 35, Gent, B-9000 Belgium
| | - Pieter Stragier
- />Laboratory of Microbiology, Department of Biochemistry and Microbiology, Ghent University, K.L. Ledeganckstraat 35, Gent, B-9000 Belgium
| | - Steve Baeyen
- />Plant Sciences Unit - Crop Protection, Institute for Agricultural and Fisheries Research - ILVO, Burg. Van Gansberghelaan 96, Merelbeke, B-9820 Belgium
| | - Annelies Haegeman
- />Plant Sciences Unit - Crop Protection, Institute for Agricultural and Fisheries Research - ILVO, Burg. Van Gansberghelaan 96, Merelbeke, B-9820 Belgium
| | - Johan Van Vaerenbergh
- />Plant Sciences Unit - Crop Protection, Institute for Agricultural and Fisheries Research - ILVO, Burg. Van Gansberghelaan 96, Merelbeke, B-9820 Belgium
| | - Martine Maes
- />Plant Sciences Unit - Crop Protection, Institute for Agricultural and Fisheries Research - ILVO, Burg. Van Gansberghelaan 96, Merelbeke, B-9820 Belgium
| | - Paul De Vos
- />Laboratory of Microbiology, Department of Biochemistry and Microbiology, Ghent University, K.L. Ledeganckstraat 35, Gent, B-9000 Belgium
- />BCCM/LMG Bacteria collection - Laboratory of Microbiology Department of Biochemistry and Microbiology, Ghent University, K.L. Ledeganckstraat 35, Gent, B-9000 Belgium
| |
Collapse
|
23
|
Boon E, Meehan CJ, Whidden C, Wong DHJ, Langille MGI, Beiko RG. Interactions in the microbiome: communities of organisms and communities of genes. FEMS Microbiol Rev 2014; 38:90-118. [PMID: 23909933 PMCID: PMC4298764 DOI: 10.1111/1574-6976.12035] [Citation(s) in RCA: 119] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Revised: 07/02/2013] [Accepted: 07/10/2013] [Indexed: 12/17/2022] Open
Abstract
A central challenge in microbial community ecology is the delineation of appropriate units of biodiversity, which can be taxonomic, phylogenetic, or functional in nature. The term 'community' is applied ambiguously; in some cases, the term refers simply to a set of observed entities, while in other cases, it requires that these entities interact with one another. Microorganisms can rapidly gain and lose genes, potentially decoupling community roles from taxonomic and phylogenetic groupings. Trait-based approaches offer a useful alternative, but many traits can be defined based on gene functions, metabolic modules, and genomic properties, and the optimal set of traits to choose is often not obvious. An analysis that considers taxon assignment and traits in concert may be ideal, with the strengths of each approach offsetting the weaknesses of the other. Individual genes also merit consideration as entities in an ecological analysis, with characteristics such as diversity, turnover, and interactions modeled using genes rather than organisms as entities. We identify some promising avenues of research that are likely to yield a deeper understanding of microbial communities that shift from observation-based questions of 'Who is there?' and 'What are they doing?' to the mechanistically driven question of 'How will they respond?'
Collapse
Affiliation(s)
- Eva Boon
- Department of Biology, Dalhousie University, Halifax, NS, Canada
| | | | | | | | | | | |
Collapse
|
24
|
Affiliation(s)
- Joel A. Farkas
- Department of Microbiology and Center for RNA Biology, Ohio State University, Columbus, Ohio 43210
| | - Jonathan W. Picking
- Department of Microbiology and Center for RNA Biology, Ohio State University, Columbus, Ohio 43210
| | - Thomas J. Santangelo
- Department of Microbiology and Center for RNA Biology, Ohio State University, Columbus, Ohio 43210
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado 80523;
| |
Collapse
|
25
|
Murugapiran SK, Huntemann M, Wei CL, Han J, Detter JC, Han C, Erkkila TH, Teshima H, Chen A, Kyrpides N, Mavrommatis K, Markowitz V, Szeto E, Ivanova N, Pagani I, Pati A, Goodwin L, Peters L, Pitluck S, Lam J, McDonald AI, Dodsworth JA, Woyke T, Hedlund BP. Thermus oshimai JL-2 and T. thermophilus JL-18 genome analysis illuminates pathways for carbon, nitrogen, and sulfur cycling. Stand Genomic Sci 2013; 7:449-68. [PMID: 24019992 PMCID: PMC3764938 DOI: 10.4056/sigs.3667269] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
The complete genomes of Thermus oshimai JL-2 and T. thermophilus JL-18 each consist of a circular chromosome, 2.07 Mb and 1.9 Mb, respectively, and two plasmids ranging from 0.27 Mb to 57.2 kb. Comparison of the T. thermophilus JL-18 chromosome with those from other strains of T. thermophilus revealed a high degree of synteny, whereas the megaplasmids from the same strains were highly plastic. The T. oshimai JL-2 chromosome and megaplasmids shared little or no synteny with other sequenced Thermus strains. Phylogenomic analyses using a concatenated set of conserved proteins confirmed the phylogenetic and taxonomic assignments based on 16S rRNA phylogenetics. Both chromosomes encode a complete glycolysis, tricarboxylic acid (TCA) cycle, and pentose phosphate pathway plus glucosidases, glycosidases, proteases, and peptidases, highlighting highly versatile heterotrophic capabilities. Megaplasmids of both strains contained a gene cluster encoding enzymes predicted to catalyze the sequential reduction of nitrate to nitrous oxide; however, the nitrous oxide reductase required for the terminal step in denitrification was absent, consistent with their incomplete denitrification phenotypes. A sox gene cluster was identified in both chromosomes, suggesting a mode of chemolithotrophy. In addition, nrf and psr gene clusters in T. oshmai JL-2 suggest respiratory nitrite ammonification and polysulfide reduction as possible modes of anaerobic respiration.
Collapse
|
26
|
Bhattacharya D, Price DC, Bicep C, Bapteste E, Sarwade M, Rajah VD, Yoon HS. Identification of a Marine Cyanophage in a Protist Single-cell Metagenome Assembly. JOURNAL OF PHYCOLOGY 2013; 49:207-212. [PMID: 27008402 DOI: 10.1111/jpy.12028] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2012] [Accepted: 08/27/2012] [Indexed: 06/05/2023]
Abstract
Analysis of microbial biodiversity is hampered by a lack of reference genomes from most bacteria, viruses, and algae. This necessitates either the cultivation of a restricted number of species for standard sequencing projects or the analysis of highly complex environmental DNA metagenome data. Single-cell genomics (SCG) offers a solution to this problem by constraining the studied DNA sample to an individual cell and its associated symbionts, prey, and pathogens. We used SCG to study marine heterotrophic amoebae related to Paulinella ovalis (A. Wulff) P.W. Johnson, P.E. Hargraves & J.M. Sieburth (Rhizaria). The genus Paulinella is best known for its photosynthetic members such as P. chromatophora Lauterborn that is the only case of plastid primary endosymbiosis known outside of algae and plants. Here, we studied the phagotrophic sister taxa of P. chromatophora that are related to P. ovalis and found one SCG assembly to contain α-cyanobacterial DNA. These cyanobacterial contigs are presumably derived from prey. We also uncovered an associated cyanophage lineage (provisionally named phage PoL_MC2). Phylogenomic analysis of the fragmented genome assembly suggested a minimum genome size of 200 Kbp for phage PoL_MC2 that encodes 179 proteins and is most closely related to Synechococcus phage S-SM2. For this phage, gene network analysis demonstrates a highly modular genome structure typical of other cyanophages. Our work demonstrates that SCG is a powerful approach for discovering algal and protist biodiversity and for elucidating biotic interactions in natural samples.
Collapse
Affiliation(s)
- Debashish Bhattacharya
- Department of Ecology, Evolution and Natural Resources and Institute of Marine and Coastal Science, Rutgers University, New Brunswick, New Jersey, 08901, USA
| | - Dana C Price
- Department of Ecology, Evolution and Natural Resources and Institute of Marine and Coastal Science, Rutgers University, New Brunswick, New Jersey, 08901, USA
| | - Cedric Bicep
- Unité Mixte de Recherche, Centre National de la Recherche Scientifique 7138, Systématique, Adaptation, Evolution, Université Pierre et Marie Curie, Paris, 75005, France
| | - Eric Bapteste
- Unité Mixte de Recherche, Centre National de la Recherche Scientifique 7138, Systématique, Adaptation, Evolution, Université Pierre et Marie Curie, Paris, 75005, France
| | - Mihir Sarwade
- Department of Ecology, Evolution Natural Resources, Rutgers University, New Brunswick, New Jersey, 08901, USA
| | - Veeran D Rajah
- Department of Ecology, Evolution Natural Resources, Rutgers University, New Brunswick, New Jersey, 08901, USA
| | - Hwan Su Yoon
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 440-746, Korea
| |
Collapse
|
27
|
Amábile-Cuevas CF. Antibiotic resistance: from Darwin to Lederberg to Keynes. Microb Drug Resist 2012; 19:73-87. [PMID: 23046150 DOI: 10.1089/mdr.2012.0115] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The emergence and spread of antibiotic-resistant bacteria reflects both, a gradual, completely Darwinian evolution, which mostly yields slight decreases in antibiotic susceptibility, along with phenotypes that are not precisely characterized as "resistance"; and sudden changes, from full susceptibility to full resistance, which are driven by a vast array of horizontal gene transfer mechanisms. Antibiotics select for more than just antibiotic resistance (i.e., increased virulence and enhanced gene exchange abilities); and many non-antibiotic agents or conditions select for or maintain antibiotic resistance traits as a result of a complex network of underlying and often overlapping mechanisms. Thus, the development of new antibiotics and thoughtful, integrated anti-infective strategies is needed to address the immediate and long-term threat of antibiotic resistance. Since the biology of resistance is complex, these new drugs and strategies will not come from free-market forces, or from "incentives" for pharmaceutical companies.
Collapse
|
28
|
Leigh JA, Albers SV, Atomi H, Allers T. Model organisms for genetics in the domain Archaea: methanogens, halophiles, Thermococcales and Sulfolobales. FEMS Microbiol Rev 2011; 35:577-608. [PMID: 21265868 DOI: 10.1111/j.1574-6976.2011.00265.x] [Citation(s) in RCA: 157] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
The tree of life is split into three main branches: eukaryotes, bacteria, and archaea. Our knowledge of eukaryotic and bacteria cell biology has been built on a foundation of studies in model organisms, using the complementary approaches of genetics and biochemistry. Archaea have led to some exciting discoveries in the field of biochemistry, but archaeal genetics has been slow to get off the ground, not least because these organisms inhabit some of the more inhospitable places on earth and are therefore believed to be difficult to culture. In fact, many species can be cultivated with relative ease and there has been tremendous progress in the development of genetic tools for both major archaeal phyla, the Euryarchaeota and the Crenarchaeota. There are several model organisms available for methanogens, halophiles, and thermophiles; in the latter group, there are genetic systems for Sulfolobales and Thermococcales. In this review, we present the advantages and disadvantages of working with each archaeal group, give an overview of their different genetic systems, and direct the neophyte archaeologist to the most appropriate model organism.
Collapse
Affiliation(s)
- John A Leigh
- Department of Microbiology, University of Washington, Seattle, WA, USA
| | | | | | | |
Collapse
|
29
|
Natural competence in the hyperthermophilic archaeon Pyrococcus furiosus facilitates genetic manipulation: construction of markerless deletions of genes encoding the two cytoplasmic hydrogenases. Appl Environ Microbiol 2011; 77:2232-8. [PMID: 21317259 DOI: 10.1128/aem.02624-10] [Citation(s) in RCA: 145] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In attempts to develop a method of introducing DNA into Pyrococcus furiosus, we discovered a variant within the wild-type population that is naturally and efficiently competent for DNA uptake. A pyrF gene deletion mutant was constructed in the genome, and the combined transformation and recombination frequencies of this strain allowed marker replacement by direct selection using linear DNA. We have demonstrated the use of this strain, designated COM1, for genetic manipulation. Using genetic selections and counterselections based on uracil biosynthesis, we generated single- and double-deletion mutants of the two gene clusters that encode the two cytoplasmic hydrogenases. The COM1 strain will provide the basis for the development of more sophisticated genetic tools allowing the study and metabolic engineering of this important hyperthermophile.
Collapse
|