1
|
Royzenblat SK, Freddolino L. Spatio-temporal organization of the E. coli chromosome from base to cellular length scales. EcoSal Plus 2024:eesp00012022. [PMID: 38864557 DOI: 10.1128/ecosalplus.esp-0001-2022] [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: 05/19/2023] [Accepted: 04/17/2024] [Indexed: 06/13/2024]
Abstract
Escherichia coli has been a vital model organism for studying chromosomal structure, thanks, in part, to its small and circular genome (4.6 million base pairs) and well-characterized biochemical pathways. Over the last several decades, we have made considerable progress in understanding the intricacies of the structure and subsequent function of the E. coli nucleoid. At the smallest scale, DNA, with no physical constraints, takes on a shape reminiscent of a randomly twisted cable, forming mostly random coils but partly affected by its stiffness. This ball-of-spaghetti-like shape forms a structure several times too large to fit into the cell. Once the physiological constraints of the cell are added, the DNA takes on overtwisted (negatively supercoiled) structures, which are shaped by an intricate interplay of many proteins carrying out essential biological processes. At shorter length scales (up to about 1 kb), nucleoid-associated proteins organize and condense the chromosome by inducing loops, bends, and forming bridges. Zooming out further and including cellular processes, topological domains are formed, which are flanked by supercoiling barriers. At the megabase-scale both large, highly self-interacting regions (macrodomains) and strong contacts between distant but co-regulated genes have been observed. At the largest scale, the nucleoid forms a helical ellipsoid. In this review, we will explore the history and recent advances that pave the way for a better understanding of E. coli chromosome organization and structure, discussing the cellular processes that drive changes in DNA shape, and what contributes to compaction and formation of dynamic structures, and in turn how bacterial chromatin affects key processes such as transcription and replication.
Collapse
Affiliation(s)
- Sonya K Royzenblat
- Cellular and Molecular Biology Program, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Lydia Freddolino
- Cellular and Molecular Biology Program, University of Michigan Medical School, Ann Arbor, Michigan, USA
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan, USA
- Department of Computational Medicine & Bioinformatics, University of Michigan Medical School, Ann Arbor, Michigan, USA
| |
Collapse
|
2
|
Altae-Tran H, Kannan S, Suberski AJ, Mears KS, Demircioglu FE, Moeller L, Kocalar S, Oshiro R, Makarova KS, Macrae RK, Koonin EV, Zhang F. Uncovering the functional diversity of rare CRISPR-Cas systems with deep terascale clustering. Science 2023; 382:eadi1910. [PMID: 37995242 PMCID: PMC10910872 DOI: 10.1126/science.adi1910] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Accepted: 09/28/2023] [Indexed: 11/25/2023]
Abstract
Microbial systems underpin many biotechnologies, including CRISPR, but the exponential growth of sequence databases makes it difficult to find previously unidentified systems. In this work, we develop the fast locality-sensitive hashing-based clustering (FLSHclust) algorithm, which performs deep clustering on massive datasets in linearithmic time. We incorporated FLSHclust into a CRISPR discovery pipeline and identified 188 previously unreported CRISPR-linked gene modules, revealing many additional biochemical functions coupled to adaptive immunity. We experimentally characterized three HNH nuclease-containing CRISPR systems, including the first type IV system with a specified interference mechanism, and engineered them for genome editing. We also identified and characterized a candidate type VII system, which we show acts on RNA. This work opens new avenues for harnessing CRISPR and for the broader exploration of the vast functional diversity of microbial proteins.
Collapse
Affiliation(s)
- Han Altae-Tran
- Howard Hughes Medical Institute; Cambridge, MA 02139, USA
- Broad Institute of MIT and Harvard; Cambridge, MA 02142, USA
- McGovern Institute for Brain Research at MIT; Cambridge, MA 02139, USA
- Department of Brain and Cognitive Science, Massachusetts Institute of Technology; Cambridge, MA 02139, USA
- Department of Biological Engineering, Massachusetts Institute of Technology; Cambridge, MA 02139, USA
| | - Soumya Kannan
- Howard Hughes Medical Institute; Cambridge, MA 02139, USA
- Broad Institute of MIT and Harvard; Cambridge, MA 02142, USA
- McGovern Institute for Brain Research at MIT; Cambridge, MA 02139, USA
- Department of Brain and Cognitive Science, Massachusetts Institute of Technology; Cambridge, MA 02139, USA
- Department of Biological Engineering, Massachusetts Institute of Technology; Cambridge, MA 02139, USA
| | - Anthony J. Suberski
- Howard Hughes Medical Institute; Cambridge, MA 02139, USA
- Broad Institute of MIT and Harvard; Cambridge, MA 02142, USA
- McGovern Institute for Brain Research at MIT; Cambridge, MA 02139, USA
- Department of Brain and Cognitive Science, Massachusetts Institute of Technology; Cambridge, MA 02139, USA
- Department of Biological Engineering, Massachusetts Institute of Technology; Cambridge, MA 02139, USA
| | - Kepler S. Mears
- Howard Hughes Medical Institute; Cambridge, MA 02139, USA
- Broad Institute of MIT and Harvard; Cambridge, MA 02142, USA
- McGovern Institute for Brain Research at MIT; Cambridge, MA 02139, USA
- Department of Brain and Cognitive Science, Massachusetts Institute of Technology; Cambridge, MA 02139, USA
- Department of Biological Engineering, Massachusetts Institute of Technology; Cambridge, MA 02139, USA
| | - F. Esra Demircioglu
- Howard Hughes Medical Institute; Cambridge, MA 02139, USA
- Broad Institute of MIT and Harvard; Cambridge, MA 02142, USA
- McGovern Institute for Brain Research at MIT; Cambridge, MA 02139, USA
- Department of Brain and Cognitive Science, Massachusetts Institute of Technology; Cambridge, MA 02139, USA
- Department of Biological Engineering, Massachusetts Institute of Technology; Cambridge, MA 02139, USA
| | - Lukas Moeller
- Howard Hughes Medical Institute; Cambridge, MA 02139, USA
- Broad Institute of MIT and Harvard; Cambridge, MA 02142, USA
- McGovern Institute for Brain Research at MIT; Cambridge, MA 02139, USA
- Department of Brain and Cognitive Science, Massachusetts Institute of Technology; Cambridge, MA 02139, USA
- Department of Biological Engineering, Massachusetts Institute of Technology; Cambridge, MA 02139, USA
| | - Selin Kocalar
- Howard Hughes Medical Institute; Cambridge, MA 02139, USA
- Broad Institute of MIT and Harvard; Cambridge, MA 02142, USA
- McGovern Institute for Brain Research at MIT; Cambridge, MA 02139, USA
- Department of Brain and Cognitive Science, Massachusetts Institute of Technology; Cambridge, MA 02139, USA
- Department of Biological Engineering, Massachusetts Institute of Technology; Cambridge, MA 02139, USA
| | - Rachel Oshiro
- Howard Hughes Medical Institute; Cambridge, MA 02139, USA
- Broad Institute of MIT and Harvard; Cambridge, MA 02142, USA
- McGovern Institute for Brain Research at MIT; Cambridge, MA 02139, USA
- Department of Brain and Cognitive Science, Massachusetts Institute of Technology; Cambridge, MA 02139, USA
- Department of Biological Engineering, Massachusetts Institute of Technology; Cambridge, MA 02139, USA
| | - Kira S. Makarova
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health; Bethesda, MD 20894, USA
| | - Rhiannon K. Macrae
- Howard Hughes Medical Institute; Cambridge, MA 02139, USA
- Broad Institute of MIT and Harvard; Cambridge, MA 02142, USA
- McGovern Institute for Brain Research at MIT; Cambridge, MA 02139, USA
- Department of Brain and Cognitive Science, Massachusetts Institute of Technology; Cambridge, MA 02139, USA
- Department of Biological Engineering, Massachusetts Institute of Technology; Cambridge, MA 02139, USA
| | - Eugene V. Koonin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health; Bethesda, MD 20894, USA
| | - Feng Zhang
- Howard Hughes Medical Institute; Cambridge, MA 02139, USA
- Broad Institute of MIT and Harvard; Cambridge, MA 02142, USA
- McGovern Institute for Brain Research at MIT; Cambridge, MA 02139, USA
- Department of Brain and Cognitive Science, Massachusetts Institute of Technology; Cambridge, MA 02139, USA
- Department of Biological Engineering, Massachusetts Institute of Technology; Cambridge, MA 02139, USA
| |
Collapse
|
3
|
George JT, Acree C, Park JU, Kong M, Wiegand T, Pignot YL, Kellogg EH, Greene EC, Sternberg SH. Mechanism of target site selection by type V-K CRISPR-associated transposases. Science 2023; 382:eadj8543. [PMID: 37972161 PMCID: PMC10771339 DOI: 10.1126/science.adj8543] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 09/23/2023] [Indexed: 11/19/2023]
Abstract
CRISPR-associated transposases (CASTs) repurpose nuclease-deficient CRISPR effectors to catalyze RNA-guided transposition of large genetic payloads. Type V-K CASTs offer potential technology advantages but lack accuracy, and the molecular basis for this drawback has remained elusive. Here, we reveal that type V-K CASTs maintain an RNA-independent, "untargeted" transposition pathway alongside RNA-dependent integration, driven by the local availability of TnsC filaments. Using cryo-electron microscopy, single-molecule experiments, and high-throughput sequencing, we found that a minimal, CRISPR-less transpososome preferentially directs untargeted integration at AT-rich sites, with additional local specificity imparted by TnsB. By exploiting this knowledge, we suppressed untargeted transposition and increased type V-K CAST specificity up to 98.1% in cells without compromising on-target integration efficiency. These findings will inform further engineering of CAST systems for accurate, kilobase-scale genome engineering applications.
Collapse
Affiliation(s)
- Jerrin Thomas George
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | - Christopher Acree
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | - Jung-Un Park
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
| | - Muwen Kong
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | - Tanner Wiegand
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | - Yanis Luca Pignot
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | - Elizabeth H. Kellogg
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
| | - Eric C. Greene
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | - Samuel H. Sternberg
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
| |
Collapse
|
4
|
Norris V, Kayser C, Muskhelishvili G, Konto-Ghiorghi Y. The roles of nucleoid-associated proteins and topoisomerases in chromosome structure, strand segregation, and the generation of phenotypic heterogeneity in bacteria. FEMS Microbiol Rev 2023; 47:fuac049. [PMID: 36549664 DOI: 10.1093/femsre/fuac049] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 12/06/2022] [Accepted: 12/21/2022] [Indexed: 12/24/2022] Open
Abstract
How to adapt to a changing environment is a fundamental, recurrent problem confronting cells. One solution is for cells to organize their constituents into a limited number of spatially extended, functionally relevant, macromolecular assemblies or hyperstructures, and then to segregate these hyperstructures asymmetrically into daughter cells. This asymmetric segregation becomes a particularly powerful way of generating a coherent phenotypic diversity when the segregation of certain hyperstructures is with only one of the parental DNA strands and when this pattern of segregation continues over successive generations. Candidate hyperstructures for such asymmetric segregation in prokaryotes include those containing the nucleoid-associated proteins (NAPs) and the topoisomerases. Another solution to the problem of creating a coherent phenotypic diversity is by creating a growth-environment-dependent gradient of supercoiling generated along the replication origin-to-terminus axis of the bacterial chromosome. This gradient is modulated by transcription, NAPs, and topoisomerases. Here, we focus primarily on two topoisomerases, TopoIV and DNA gyrase in Escherichia coli, on three of its NAPs (H-NS, HU, and IHF), and on the single-stranded binding protein, SSB. We propose that the combination of supercoiling-gradient-dependent and strand-segregation-dependent topoisomerase activities result in significant differences in the supercoiling of daughter chromosomes, and hence in the phenotypes of daughter cells.
Collapse
Affiliation(s)
- Vic Norris
- University of Rouen, Laboratory of Bacterial Communication and Anti-infection Strategies, EA 4312, 76821 Mont Saint Aignan, France
| | - Clara Kayser
- University of Rouen, Laboratory of Bacterial Communication and Anti-infection Strategies, EA 4312, 76821 Mont Saint Aignan, France
| | - Georgi Muskhelishvili
- Agricultural University of Georgia, School of Natural Sciences, 0159 Tbilisi, Georgia
| | - Yoan Konto-Ghiorghi
- University of Rouen, Laboratory of Bacterial Communication and Anti-infection Strategies, EA 4312, 76821 Mont Saint Aignan, France
| |
Collapse
|
5
|
Thabet MA, Penadés JR, Haag AF. The ClpX protease is essential for inactivating the CI master repressor and completing prophage induction in Staphylococcus aureus. Nat Commun 2023; 14:6599. [PMID: 37852980 PMCID: PMC10584840 DOI: 10.1038/s41467-023-42413-0] [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: 09/22/2022] [Accepted: 10/10/2023] [Indexed: 10/20/2023] Open
Abstract
Bacteriophages (phages) are the most abundant biological entities on Earth, exerting a significant influence on the dissemination of bacterial virulence, pathogenicity, and antimicrobial resistance. Temperate phages integrate into the bacterial chromosome in a dormant state through intricate regulatory mechanisms. These mechanisms repress lytic genes while facilitating the expression of integrase and the CI master repressor. Upon bacterial SOS response activation, the CI repressor undergoes auto-cleavage, producing two fragments with the N-terminal domain (NTD) retaining significant DNA-binding ability. The process of relieving CI NTD repression, essential for prophage induction, remains unknown. Here we show a specific interaction between the ClpX protease and CI NTD repressor fragment of phages Ф11 and 80α in Staphylococcus aureus. This interaction is necessary and sufficient for prophage activation after SOS-mediated CI auto-cleavage, defining the final stage in the prophage induction cascade. Our findings unveil unexpected roles of bacterial protease ClpX in phage biology.
Collapse
Affiliation(s)
- Mohammed A Thabet
- School of Infection & Immunity, University of Glasgow, G12 8TA, Glasgow, UK
- Department of Biology, Faculty of Science, Al-Baha University, Al-Baha city, Al Aqiq, 65779, Kingdom of Saudi Arabia
| | - José R Penadés
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, SW7 2AZ, UK
| | - Andreas F Haag
- School of Infection & Immunity, University of Glasgow, G12 8TA, Glasgow, UK.
- School of Medicine, University of St Andrews, North Haugh, St Andrews, KY16 9TF, UK.
| |
Collapse
|
6
|
George JT, Acree C, Park JU, Kong M, Wiegand T, Pignot YL, Kellogg EH, Greene EC, Sternberg SH. Mechanism of target site selection by type V-K CRISPR-associated transposases. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.14.548620. [PMID: 37503092 PMCID: PMC10370016 DOI: 10.1101/2023.07.14.548620] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Unlike canonical CRISPR-Cas systems that rely on RNA-guided nucleases for target cleavage, CRISPR-associated transposases (CASTs) repurpose nuclease-deficient CRISPR effectors to facilitate RNA-guided transposition of large genetic payloads. Type V-K CASTs offer several potential upsides for genome engineering, due to their compact size, easy programmability, and unidirectional integration. However, these systems are substantially less accurate than type I-F CASTs, and the molecular basis for this difference has remained elusive. Here we reveal that type V-K CASTs undergo two distinct mobilization pathways with remarkably different specificities: RNA-dependent and RNA-independent transposition. Whereas RNA-dependent transposition relies on Cas12k for accurate target selection, RNA-independent integration events are untargeted and primarily driven by the local availability of TnsC filaments. The cryo-EM structure of the untargeted complex reveals a TnsB-TnsC-TniQ transpososome that encompasses two turns of a TnsC filament and otherwise resembles major architectural aspects of the Cas12k-containing transpososome. Using single-molecule experiments and genome-wide meta-analyses, we found that AT-rich sites are preferred substrates for untargeted transposition and that the TnsB transposase also imparts local specificity, which collectively determine the precise insertion site. Knowledge of these motifs allowed us to direct untargeted transposition events to specific hotspot regions of a plasmid. Finally, by exploiting TnsB's preference for on-target integration and modulating the availability of TnsC, we suppressed RNA-independent transposition events and increased type V-K CAST specificity up to 98.1%, without compromising the efficiency of on-target integration. Collectively, our results reveal the importance of dissecting target site selection mechanisms and highlight new opportunities to leverage CAST systems for accurate, kilobase-scale genome engineering applications.
Collapse
Affiliation(s)
- Jerrin Thomas George
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | - Christopher Acree
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
- Present address: Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37212, USA
| | - Jung-Un Park
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
- Future address: Department of Structural Biology. St Jude Children’s Research Hospital, Memphis, TN 38105, USA
| | - Muwen Kong
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | - Tanner Wiegand
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | - Yanis Luca Pignot
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
- Present address: Department of Biochemistry, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Elizabeth H. Kellogg
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
- Future address: Department of Structural Biology. St Jude Children’s Research Hospital, Memphis, TN 38105, USA
| | - Eric C. Greene
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | - Samuel H. Sternberg
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
| |
Collapse
|
7
|
Fernandez M, Shkumatov AV, Liu Y, Stulemeijer C, Derclaye S, Efremov R, Hallet B, Alsteens D. AFM-based force spectroscopy unravels stepwise formation of the DNA transposition complex in the widespread Tn3 family mobile genetic elements. Nucleic Acids Res 2023; 51:4929-4941. [PMID: 37026471 PMCID: PMC10250215 DOI: 10.1093/nar/gkad241] [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: 12/21/2022] [Revised: 03/03/2023] [Accepted: 03/23/2023] [Indexed: 04/08/2023] Open
Abstract
Transposon Tn4430 belongs to a widespread family of bacterial transposons, the Tn3 family, which plays a prevalent role in the dissemination of antibiotic resistance among pathogens. Despite recent data on the structural architecture of the transposition complex, the molecular mechanisms underlying the replicative transposition of these elements are still poorly understood. Here, we use force-distance curve-based atomic force microscopy to probe the binding of the TnpA transposase of Tn4430 to DNA molecules containing one or two transposon ends and to extract the thermodynamic and kinetic parameters of transposition complex assembly. Comparing wild-type TnpA with previously isolated deregulated TnpA mutants supports a stepwise pathway for transposition complex formation and activation during which TnpA first binds as a dimer to a single transposon end and then undergoes a structural transition that enables it to bind the second end cooperatively and to become activated for transposition catalysis, the latter step occurring at a much faster rate for the TnpA mutants. Our study thus provides an unprecedented approach to probe the dynamic of a complex DNA processing machinery at the single-particle level.
Collapse
Affiliation(s)
- Maricruz Fernandez
- NanoBioPhysics lab, Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
- Biochemistry and Genetics of Microorganisms, Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Alexander V Shkumatov
- Center for Structural Biology, Vlaams Instituut voor Biotechnologie, Brussels, Belgium
- Structural Biology Brussels, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Yun Liu
- Center for Structural Biology, Vlaams Instituut voor Biotechnologie, Brussels, Belgium
- Structural Biology Brussels, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Claire Stulemeijer
- Biochemistry and Genetics of Microorganisms, Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Sylvie Derclaye
- NanoBioPhysics lab, Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Rouslan G Efremov
- Center for Structural Biology, Vlaams Instituut voor Biotechnologie, Brussels, Belgium
- Structural Biology Brussels, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Bernard Hallet
- Biochemistry and Genetics of Microorganisms, Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - David Alsteens
- NanoBioPhysics lab, Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| |
Collapse
|
8
|
Zhang M, Hao Y, Yi Y, Liu S, Sun Q, Tan X, Tang S, Xiao X, Jian H. Unexplored diversity and ecological functions of transposable phages. THE ISME JOURNAL 2023:10.1038/s41396-023-01414-z. [PMID: 37069234 DOI: 10.1038/s41396-023-01414-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 04/02/2023] [Accepted: 04/05/2023] [Indexed: 04/19/2023]
Abstract
Phages are prevalent in diverse environments and play major ecological roles attributed to their tremendous diversity and abundance. Among these viruses, transposable phages (TBPs) are exceptional in terms of their unique lifestyle, especially their replicative transposition. Although several TBPs have been isolated and the life cycle of the representative phage Mu has been extensively studied, the diversity distribution and ecological functions of TBPs on the global scale remain unknown. Here, by mining TBPs from enormous microbial genomes and viromes, we established a TBP genome dataset (TBPGD), that expands the number of accessible TBP genomes 384-fold. TBPs are prevalent in diverse biomes and show great genetic diversity. Based on taxonomic evaluations, we propose the categorization of TBPs into four viral groups, including 11 candidate subfamilies. TBPs infect multiple bacterial phyla, and seem to infect a wider range of hosts than non-TBPs. Diverse auxiliary metabolic genes (AMGs) are identified in the TBP genomes, and genes related to glycoside hydrolases and pyrimidine deoxyribonucleotide biosynthesis are highly enriched. Finally, the influences of TBPs on their hosts are experimentally examined by using the marine bacterium Shewanella psychrophila WP2 and its infecting transposable phage SP2. Collectively, our findings greatly expand the genetic diversity of TBPs, and comprehensively reveal their potential influences in various ecosystems.
Collapse
Affiliation(s)
- Mujie Zhang
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Development Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Yali Hao
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Development Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Yi Yi
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Development Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Shunzhang Liu
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Development Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Qingyang Sun
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Development Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Xiaoli Tan
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Development Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Shan Tang
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Development Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Xiang Xiao
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Development Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
- Yazhou Bay Institute of Deepsea Sci-Tech, Shanghai Jiao Tong University, Sanya, China
| | - Huahua Jian
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Development Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China.
- Yazhou Bay Institute of Deepsea Sci-Tech, Shanghai Jiao Tong University, Sanya, China.
| |
Collapse
|
9
|
Precise cut-and-paste DNA insertion using engineered type V-K CRISPR-associated transposases. Nat Biotechnol 2023:10.1038/s41587-022-01574-x. [PMID: 36593413 DOI: 10.1038/s41587-022-01574-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 10/14/2022] [Indexed: 01/03/2023]
Abstract
CRISPR-associated transposases (CASTs) enable recombination-independent, multi-kilobase DNA insertions at RNA-programmed genomic locations. However, the utility of type V-K CASTs is hindered by high off-target integration and a transposition mechanism that results in a mixture of desired simple cargo insertions and undesired plasmid cointegrate products. Here we overcome both limitations by engineering new CASTs with improved integration product purity and genome-wide specificity. To do so, we engineered a nicking homing endonuclease fusion to TnsB (named HELIX) to restore the 5' nicking capability needed for cargo excision on the DNA donor. HELIX enables cut-and-paste DNA insertion with up to 99.4% simple insertion product purity, while retaining robust integration efficiencies on genomic targets. HELIX has substantially higher on-target specificity than canonical CASTs, and we identify several novel factors that further regulate targeted and genome-wide integration. Finally, we extend HELIX to other type V-K orthologs and demonstrate the feasibility of HELIX-mediated integration in human cell contexts.
Collapse
|
10
|
Shaskolskiy B, Kravtsov D, Kandinov I, Dementieva E, Gryadunov D. Genomic Diversity and Chromosomal Rearrangements in Neisseria gonorrhoeae and Neisseria meningitidis. Int J Mol Sci 2022; 23:ijms232415644. [PMID: 36555284 PMCID: PMC9778887 DOI: 10.3390/ijms232415644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 11/18/2022] [Accepted: 12/07/2022] [Indexed: 12/14/2022] Open
Abstract
Chromosomal rearrangements in N. gonorrhoeae and N. meningitidis were studied with the determination of mobile elements and their role in rearrangements. The results of whole-genome sequencing and de novo genome assembly for 50 N. gonorrhoeae isolates collected in Russia were compared with 96 genomes of N. gonorrhoeae and 138 genomes of N. meningitidis from the databases. Rearrangement events with the determination of the coordinates of syntenic blocks were analyzed using the SibeliaZ software v.1.2.5, the minimum number of events that allow one genome to pass into another was calculated using the DCJ-indel model using the UniMoG program v.1.0. Population-level analysis revealed a stronger correlation between changes in the gene order and phylogenetic proximity for N. meningitidis in contrast to N. gonorrhoeae. Mobile elements were identified, including Correa elements; Spencer-Smith elements (in N. gonorrhoeae); Neisserial intergenic mosaic elements; IS elements of IS5, IS30, IS110, IS1595 groups; Nf1-Nf3 prophages; NgoФ1-NgoФ9 prophages; and Mu-like prophages Pnm1, Pnm2, MuMenB (in N. meningitidis). More than 44% of the observed rearrangements most likely occurred with the participation of mobile elements, including prophages. No differences were found between the Russian and global N. gonorrhoeae population both in terms of rearrangement events and in the number of transposable elements in genomes.
Collapse
|
11
|
Shkumatov AV, Aryanpour N, Oger CA, Goossens G, Hallet BF, Efremov RG. Structural insight into Tn3 family transposition mechanism. Nat Commun 2022; 13:6155. [PMID: 36257990 PMCID: PMC9579193 DOI: 10.1038/s41467-022-33871-z] [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] [Received: 02/22/2022] [Accepted: 10/05/2022] [Indexed: 12/24/2022] Open
Abstract
Transposons are diverse mobile genetic elements that play the critical role as genome architects in all domains of life. Tn3 is a widespread family and among the first identified bacterial transposons famed for their contribution to the dissemination of antibiotic resistance. Transposition within this family is mediated by a large TnpA transposase, which facilitates both transposition and target immunity. Howtever, a structural framework required for understanding the mechanism of TnpA transposition is lacking. Here, we describe the cryo-EM structures of TnpA from Tn4430 in the apo form and paired with transposon ends before and after DNA cleavage and strand transfer. We show that TnpA has an unusual architecture and exhibits a family specific regulatory mechanism involving metamorphic refolding of the RNase H-like catalytic domain. The TnpA structure, constrained by a double dimerization interface, creates a peculiar topology that suggests a specific role for the target DNA in transpososome assembly and activation.
Collapse
Affiliation(s)
- Alexander V. Shkumatov
- grid.11486.3a0000000104788040Center for Structural Biology, Vlaams Instituut voor Biotechnologie, Brussels, Belgium ,grid.8767.e0000 0001 2290 8069Structural Biology Brussels, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium ,Present Address: Confo Therapeutics, Brussels, Belgium
| | - Nicolas Aryanpour
- grid.7942.80000 0001 2294 713XLouvain Institue of Biomolecular Science and Technology, Université Catholique de Louvain (UCLouvain), Croix du Sud 4/5, 1348 Louvain-la-Neuve, Belgium
| | - Cédric A. Oger
- grid.7942.80000 0001 2294 713XLouvain Institue of Biomolecular Science and Technology, Université Catholique de Louvain (UCLouvain), Croix du Sud 4/5, 1348 Louvain-la-Neuve, Belgium
| | - Gérôme Goossens
- grid.7942.80000 0001 2294 713XLouvain Institue of Biomolecular Science and Technology, Université Catholique de Louvain (UCLouvain), Croix du Sud 4/5, 1348 Louvain-la-Neuve, Belgium ,Present Address: Thermo Fisher Scientific, Seneffe, Belgium
| | - Bernard F. Hallet
- grid.7942.80000 0001 2294 713XLouvain Institue of Biomolecular Science and Technology, Université Catholique de Louvain (UCLouvain), Croix du Sud 4/5, 1348 Louvain-la-Neuve, Belgium
| | - Rouslan G. Efremov
- grid.11486.3a0000000104788040Center for Structural Biology, Vlaams Instituut voor Biotechnologie, Brussels, Belgium ,grid.8767.e0000 0001 2290 8069Structural Biology Brussels, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| |
Collapse
|
12
|
Gu X, Huang D, Chen J, Li X, Zhou Y, Huang M, Liu Y, Yu P. Bacterial Inactivation and Biofilm Disruption through Indigenous Prophage Activation Using Low-Intensity Cold Atmospheric Plasma. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:8920-8931. [PMID: 35438974 DOI: 10.1021/acs.est.2c01516] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Biofilms can be pervasive and problematic in water treatment and distribution systems but are difficult to eradicate due to hindered penetration of antimicrobial chemicals. Here, we demonstrate that indigenous prophages activated by low-intensity plasma have the potential for efficient bacterial inactivation and biofilm disruption. Specifically, low-intensity plasma treatment (i.e., 35.20 W) elevated the intracellular oxidative reactive species (ROS) levels by 184%, resulting in the activation of prophage lambda (λ) within antibiotic-resistant Escherichia coli K-12 (lambda+) [E. coli (λ+)]. The phage activation efficiency was 6.50-fold higher than the conventional mitomycin C induction. Following a cascading effect, the activated phages were released upon the lysis of E. coli (λ+), which propagated further and lysed phage-susceptible E. coli K-12 (lambda-) [E. coli (λ-)] within the biofilm. Bacterial intracellular ROS analysis and ROS scavenger tests revealed the importance of plasma-generated ROS (e.g., •OH, 1O2, and •O2-) and associated intracellular oxidative stress on prophage activation. In a mixed-species biofilm on a permeable membrane surface, our "inside-out" strategy could inactivate total bacteria by 49% and increase the membrane flux by 4.33-fold. Furthermore, the metagenomic analysis revealed that the decrease in bacterial abundance was closely associated with the increase in phage levels. As a proof-of-concept, this is the first demonstration of indigenous prophage activations by low-intensity plasma for antibiotic-resistant bacterial inactivation and biofilm eradication, which opens up a new avenue for managing associated microbial problems.
Collapse
Affiliation(s)
- Xia Gu
- College of Environmental Science and Engineering, Donghua University, Songjiang, Shanghai 201620, China
| | - Dan Huang
- College of Environment and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Juhong Chen
- Department of Biological Systems Engineering, Virginia Tech, Blacksburg, Virginia 24061-0131, United States
| | - Xiang Li
- College of Environmental Science and Engineering, Donghua University, Songjiang, Shanghai 201620, China
| | - Yongquan Zhou
- College of Environmental Science and Engineering, Donghua University, Songjiang, Shanghai 201620, China
| | - Manhong Huang
- College of Environmental Science and Engineering, Donghua University, Songjiang, Shanghai 201620, China
| | - Yanan Liu
- College of Environmental Science and Engineering, Donghua University, Songjiang, Shanghai 201620, China
| | - Pingfeng Yu
- College of Environment and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| |
Collapse
|
13
|
Bordenstein SR, Bordenstein SR. Widespread phages of endosymbionts: Phage WO genomics and the proposed taxonomic classification of Symbioviridae. PLoS Genet 2022; 18:e1010227. [PMID: 35666732 PMCID: PMC9203015 DOI: 10.1371/journal.pgen.1010227] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 06/16/2022] [Accepted: 04/29/2022] [Indexed: 11/19/2022] Open
Abstract
Wolbachia are the most common obligate, intracellular bacteria in animals. They exist worldwide in arthropod and nematode hosts in which they commonly act as reproductive parasites or mutualists, respectively. Bacteriophage WO, the largest of Wolbachia’s mobile elements, includes reproductive parasitism genes, serves as a hotspot for genetic divergence and genomic rearrangement of the bacterial chromosome, and uniquely encodes a Eukaryotic Association Module with eukaryotic-like genes and an ensemble of putative host interaction genes. Despite WO’s relevance to genome evolution, selfish genetics, and symbiotic applications, relatively little is known about its origin, host range, diversification, and taxonomic classification. Here we analyze the most comprehensive set of 150 Wolbachia and phage WO assemblies to provide a framework for discretely organizing and naming integrated phage WO genomes. We demonstrate that WO is principally in arthropod Wolbachia with relatives in diverse endosymbionts and metagenomes, organized into four variants related by gene synteny, often oriented opposite the putative origin of replication in the Wolbachia chromosome, and the large serine recombinase is an ideal typing tool to distinguish the four variants. We identify a novel, putative lytic cassette and WO’s association with a conserved eleven gene island, termed Undecim Cluster, that is enriched with virulence-like genes. Finally, we evaluate WO-like Islands in the Wolbachia genome and discuss a new model in which Octomom, a notable WO-like Island, arose from a split with WO. Together, these findings establish the first comprehensive Linnaean taxonomic classification of endosymbiont phages, including non-Wolbachia phages from aquatic environments, that includes a new family and two new genera to capture the collective relatedness of these viruses.
Collapse
Affiliation(s)
- Sarah R. Bordenstein
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, United States of America
- Vanderbilt Microbiome Innovation Center, Vanderbilt University, Nashville, Tennessee, United States of America
- * E-mail:
| | - Seth R. Bordenstein
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, United States of America
- Vanderbilt Microbiome Innovation Center, Vanderbilt University, Nashville, Tennessee, United States of America
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, Tennessee, United States of America
- Vanderbilt Institute of Infection, Immunology, and Inflammation, Vanderbilt University, Nashville, Tennessee, United States of America
| |
Collapse
|
14
|
Kaczmarska Z, Czarnocki-Cieciura M, Górecka-Minakowska KM, Wingo RJ, Jackiewicz J, Zajko W, Poznański JT, Rawski M, Grant T, Peters JE, Nowotny M. Structural basis of transposon end recognition explains central features of Tn7 transposition systems. Mol Cell 2022; 82:2618-2632.e7. [PMID: 35654042 PMCID: PMC9308760 DOI: 10.1016/j.molcel.2022.05.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 03/02/2022] [Accepted: 05/03/2022] [Indexed: 02/06/2023]
Abstract
Tn7 is a bacterial transposon with relatives containing element-encoded CRISPR-Cas systems mediating RNA-guided transposon insertion. Here, we present the 2.7 Å cryoelectron microscopy structure of prototypic Tn7 transposase TnsB interacting with the transposon end DNA. When TnsB interacts across repeating binding sites, it adopts a beads-on-a-string architecture, where the DNA-binding and catalytic domains are arranged in a tiled and intertwined fashion. The DNA-binding domains form few base-specific contacts leading to a binding preference that requires multiple weakly conserved sites at the appropriate spacing to achieve DNA sequence specificity. TnsB binding imparts differences in the global structure of the protein-bound DNA ends dictated by the spacing or overlap of binding sites explaining functional differences in the left and right ends of the element. We propose a model of the strand-transfer complex in which the terminal TnsB molecule is rearranged so that its catalytic domain is in a position conducive to transposition.
Collapse
Affiliation(s)
- Zuzanna Kaczmarska
- Laboratory of Protein Structure, International Institute of Molecular and Cell Biology, 02-109 Warsaw, Poland
| | - Mariusz Czarnocki-Cieciura
- Laboratory of Protein Structure, International Institute of Molecular and Cell Biology, 02-109 Warsaw, Poland
| | | | - Robert J Wingo
- Department of Microbiology, Cornell University, Ithaca, NY 14853, USA
| | - Justyna Jackiewicz
- Laboratory of Protein Structure, International Institute of Molecular and Cell Biology, 02-109 Warsaw, Poland
| | - Weronika Zajko
- Laboratory of Protein Structure, International Institute of Molecular and Cell Biology, 02-109 Warsaw, Poland
| | - Jarosław T Poznański
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland
| | - Michał Rawski
- Malopolska Centre of Biotechnology, Jagiellonian University, 30-387 Krakow, Poland
| | - Timothy Grant
- John and Jeanne Rowe Center for Research in Virology, Morgridge Institute for Research, Madison, WI 53715, USA; Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Joseph E Peters
- Department of Microbiology, Cornell University, Ithaca, NY 14853, USA.
| | - Marcin Nowotny
- Laboratory of Protein Structure, International Institute of Molecular and Cell Biology, 02-109 Warsaw, Poland.
| |
Collapse
|
15
|
Tn
FLXopen
: Markerless Transposons for Functional Fluorescent Fusion Proteins and Protein Interaction Prediction. Microbiol Spectr 2022; 10:e0242821. [PMID: 35499319 PMCID: PMC9241775 DOI: 10.1128/spectrum.02428-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Fluorescence microscopy of cells expressing proteins translationally linked to a fluorophore can be a powerful tool to investigate protein localization dynamics in vivo. One major obstacle to reliably analyze biologically relevant localization is the construction of a fusion protein that is both fluorescent and functional. Here, we develop a strategy to construct fluorescent fusions at theoretically any location in the protein by using TnFLXopen random transposon mutagenesis to randomly insert a gene encoding a fluorescent protein. Moreover, insertions within a target gene are enriched by an inducible gene-trap strategy and selection by fluorescence activated cell sorting. Using this approach, we isolate a variety of fluorescent fusions to FtsZ that exhibit ring-like localization and a fusion to the flagellar stator protein that both is functional for supporting motility and localizes as fluorescent puncta. Finally, we further modify TnFLXopen to insert the coding sequence for the C-terminal half of mVenus for use in bimolecular fluorescence complementation (BiFC) and the in vivo detection of protein-protein interaction candidates. As proof-of-concept, the DivIVA polar scaffolding protein was fused to the N terminus of mVenus, the C terminus of mVenus was delivered by transposition, and a combination of fluorescence activated cell sorter (FACS) sorting and whole-genome sequencing identified the known self-interaction of DivIVA as well as other possible candidate interactors. We suggest that the FACS selection is a viable alternative to antibiotic selection in transposon mutagenesis that can generate new fluorescent tools for in vivo protein characterization. IMPORTANCE Transposon mutagenesis is a powerful tool for random mutagenesis, as insertion of a transposon and accompanying antibiotic resistance cassette often disrupt gene function. Here, we present a series of transposons with fluorescent protein genes which, when integrated in frame, may be selected with a fluorescence activated cell sorter (FACS). An open reading frame runs continuously through the transposon such that fluorescent protein fusions may be inserted theoretically anywhere in the primary sequence and potentially preserve function of the target protein. Finally, the transposons were further modified to randomly insert a partial fluorescent protein compatible with bimolecular fluorescence complementation (BiFC) to identify protein interaction candidates.
Collapse
|
16
|
Forsberg KJ, Schmidtke DT, Werther R, Uribe RV, Hausman D, Sommer MOA, Stoddard BL, Kaiser BK, Malik HS. The novel anti-CRISPR AcrIIA22 relieves DNA torsion in target plasmids and impairs SpyCas9 activity. PLoS Biol 2021; 19:e3001428. [PMID: 34644300 PMCID: PMC8545432 DOI: 10.1371/journal.pbio.3001428] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 10/25/2021] [Accepted: 09/28/2021] [Indexed: 11/18/2022] Open
Abstract
To overcome CRISPR-Cas defense systems, many phages and mobile genetic elements (MGEs) encode CRISPR-Cas inhibitors called anti-CRISPRs (Acrs). Nearly all characterized Acrs directly bind Cas proteins to inactivate CRISPR immunity. Here, using functional metagenomic selection, we describe AcrIIA22, an unconventional Acr found in hypervariable genomic regions of clostridial bacteria and their prophages from human gut microbiomes. AcrIIA22 does not bind strongly to SpyCas9 but nonetheless potently inhibits its activity against plasmids. To gain insight into its mechanism, we obtained an X-ray crystal structure of AcrIIA22, which revealed homology to PC4-like nucleic acid-binding proteins. Based on mutational analyses and functional assays, we deduced that acrIIA22 encodes a DNA nickase that relieves torsional stress in supercoiled plasmids. This may render them less susceptible to SpyCas9, which uses free energy from negative supercoils to form stable R-loops. Modifying DNA topology may provide an additional route to CRISPR-Cas resistance in phages and MGEs.
Collapse
Affiliation(s)
- Kevin J. Forsberg
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- * E-mail:
| | - Danica T. Schmidtke
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Rachel Werther
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Ruben V. Uribe
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - Deanna Hausman
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Morten O. A. Sommer
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - Barry L. Stoddard
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Brett K. Kaiser
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- Department of Biology, Seattle University, Seattle, Washington, United States of America
| | - Harmit S. Malik
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| |
Collapse
|
17
|
Ma CH, Javanmardi K, Finkelstein IJ, Jayaram M. Disintegration promotes protospacer integration by the Cas1-Cas2 complex. eLife 2021; 10:65763. [PMID: 34435949 PMCID: PMC8390005 DOI: 10.7554/elife.65763] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 08/11/2021] [Indexed: 12/16/2022] Open
Abstract
‘Disintegration’—the reversal of transposon DNA integration at a target site—is regarded as an abortive off-pathway reaction. Here, we challenge this view with a biochemical investigation of the mechanism of protospacer insertion, which is mechanistically analogous to DNA transposition, by the Streptococcus pyogenes Cas1-Cas2 complex. In supercoiled target sites, the predominant outcome is the disintegration of one-ended insertions that fail to complete the second integration event. In linear target sites, one-ended insertions far outnumber complete protospacer insertions. The second insertion event is most often accompanied by the disintegration of the first, mediated either by the 3′-hydroxyl exposed during integration or by water. One-ended integration intermediates may mature into complete spacer insertions via DNA repair pathways that are also involved in transposon mobility. We propose that disintegration-promoted integration is functionally important in the adaptive phase of CRISPR-mediated bacterial immunity, and perhaps in other analogous transposition reactions.
Collapse
Affiliation(s)
- Chien-Hui Ma
- Department of Molecular Biosciences and Institute of Cell and Molecular Biology, University of Texas at Austin, Austin, United States
| | - Kamyab Javanmardi
- Department of Molecular Biosciences and Institute of Cell and Molecular Biology, University of Texas at Austin, Austin, United States
| | - Ilya J Finkelstein
- Department of Molecular Biosciences and Institute of Cell and Molecular Biology, University of Texas at Austin, Austin, United States.,Center for Systems and Synthetic Biology, University of Texas at Austin, Austin, United States
| | - Makkuni Jayaram
- Department of Molecular Biosciences and Institute of Cell and Molecular Biology, University of Texas at Austin, Austin, United States
| |
Collapse
|
18
|
Sklyar T, Kurahina N, Lavrentieva K, Burlaka V, Lykholat T, Lykholat O. Autonomic (Mobile) Genetic Elements of Bacteria and Their Hierarchy. CYTOL GENET+ 2021. [DOI: 10.3103/s0095452721030099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
19
|
Cieślik M, Bagińska N, Jończyk-Matysiak E, Węgrzyn A, Węgrzyn G, Górski A. Temperate Bacteriophages-The Powerful Indirect Modulators of Eukaryotic Cells and Immune Functions. Viruses 2021; 13:v13061013. [PMID: 34071422 PMCID: PMC8228536 DOI: 10.3390/v13061013] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 05/22/2021] [Accepted: 05/27/2021] [Indexed: 12/11/2022] Open
Abstract
Bacteriophages are natural biological entities that limit the growth and amplification of bacteria. They are important stimulators of evolutionary variability in bacteria, and currently are considered a weapon against antibiotic resistance of bacteria. Nevertheless, apart from their antibacterial activity, phages may act as modulators of mammalian immune responses. In this paper, we focus on temperate phages able to execute the lysogenic development, which may shape animal or human immune response by influencing various processes, including phagocytosis of bacterial invaders and immune modulation of mammalian host cells.
Collapse
Affiliation(s)
- Martyna Cieślik
- Bacteriophage Laboratory, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, 53-114 Wrocław, Poland; (M.C.); (N.B.); (E.J.-M.)
| | - Natalia Bagińska
- Bacteriophage Laboratory, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, 53-114 Wrocław, Poland; (M.C.); (N.B.); (E.J.-M.)
| | - Ewa Jończyk-Matysiak
- Bacteriophage Laboratory, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, 53-114 Wrocław, Poland; (M.C.); (N.B.); (E.J.-M.)
| | - Alicja Węgrzyn
- Laboratory of Phage Therapy, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Kładki 24, 80-822 Gdańsk, Poland;
| | - Grzegorz Węgrzyn
- Department of Molecular Biology, University of Gdańsk, Wita Stwosza 59, 80-308 Gdańsk, Poland;
| | - Andrzej Górski
- Bacteriophage Laboratory, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, 53-114 Wrocław, Poland; (M.C.); (N.B.); (E.J.-M.)
- Phage Therapy Unit, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, 53-114 Wrocław, Poland
- Infant Jesus Hospital, The Medical University of Warsaw, 02-006 Warsaw, Poland
- Correspondence:
| |
Collapse
|
20
|
Characterization and Genomic Analysis of ɸSHP3, a New Transposable Bacteriophage Infecting Stenotrophomonas maltophilia. J Virol 2021; 95:JVI.00019-21. [PMID: 33536173 DOI: 10.1128/jvi.00019-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 01/29/2021] [Indexed: 01/21/2023] Open
Abstract
This study describes a novel transposable bacteriophage, ɸSHP3, continuously released by Stenotrophomonas maltophilia strain c31. Morphological observation and genomic analysis revealed that ɸSHP3 is a siphovirus with a 37,611-bp genome that encodes 51 putative proteins. Genomic comparisons indicated that ɸSHP3 is a B3-like transposable phage. Its genome configuration is similar to that of Pseudomonas phage B3, except for the DNA modification module. Similar to B3-like phages, the putative transposase B of ɸSHP3 is a homolog of the type two secretion component ExeA, which is proposed to serve as a potential virulence factor. Moreover, most proteins of ɸSHP3 have homologs in transposable phages, but only ɸSHP3 carries an RdgC-like protein encoded by gene 3, which exhibits exonuclease activity in vitro Two genes and their promoters coding for ɸSHP3 regulatory proteins were identified and appear to control the lytic-lysogenic switch. One of the proteins represses one promoter activity and confers immunity to ɸSHP3 superinfection in vivo The short regulatory region, in addition to the canonical bacterial promoter sequences, displays one LexA and two CpxR recognition sequences. This suggests that LexA and the CpxR/CpxA two-component system might be involved in the control of the ɸSHP3 genetic switch.IMPORTANCE S. maltophilia is an emerging global pathogenic bacterium that displays genetic diversity in both environmental and clinical strains. Transposable phages have long been known to improve the genetic diversity of bacterial strains by transposition. More than a dozen phages of S. maltophilia have been characterized. However, no transposable phage infecting S. maltophilia has been reported to date. Characterization of the first transposable phage, ɸSHP3, from S. maltophilia will contribute to our understanding of host-phage interactions and genetic diversity, especially the interchange of genetic materials among S. maltophilia.
Collapse
|
21
|
Reverchon S, Meyer S, Forquet R, Hommais F, Muskhelishvili G, Nasser W. The nucleoid-associated protein IHF acts as a 'transcriptional domainin' protein coordinating the bacterial virulence traits with global transcription. Nucleic Acids Res 2021; 49:776-790. [PMID: 33337488 PMCID: PMC7826290 DOI: 10.1093/nar/gkaa1227] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 11/30/2020] [Accepted: 12/07/2020] [Indexed: 02/04/2023] Open
Abstract
Bacterial pathogenic growth requires a swift coordination of pathogenicity function with various kinds of environmental stress encountered in the course of host infection. Among the factors critical for bacterial adaptation are changes of DNA topology and binding effects of nucleoid-associated proteins transducing the environmental signals to the chromosome and coordinating the global transcriptional response to stress. In this study, we use the model phytopathogen Dickeya dadantii to analyse the organisation of transcription by the nucleoid-associated heterodimeric protein IHF. We inactivated the IHFα subunit of IHF thus precluding the IHFαβ heterodimer formation and determined both phenotypic effects of ihfA mutation on D. dadantii virulence and the transcriptional response under various conditions of growth. We show that ihfA mutation reorganises the genomic expression by modulating the distribution of chromosomal DNA supercoils at different length scales, thus affecting many virulence genes involved in both symptomatic and asymptomatic phases of infection, including those required for pectin catabolism. Altogether, we propose that IHF heterodimer is a 'transcriptional domainin' protein, the lack of which impairs the spatiotemporal organisation of transcriptional stress-response domains harbouring various virulence traits, thus abrogating the pathogenicity of D. dadantii.
Collapse
Affiliation(s)
- Sylvie Reverchon
- Univ Lyon, Université Claude Bernard Lyon 1, INSA-Lyon, CNRS, UMR5240 MAP, F-69622, France
| | - Sam Meyer
- Univ Lyon, Université Claude Bernard Lyon 1, INSA-Lyon, CNRS, UMR5240 MAP, F-69622, France
| | - Raphaël Forquet
- Univ Lyon, Université Claude Bernard Lyon 1, INSA-Lyon, CNRS, UMR5240 MAP, F-69622, France
| | - Florence Hommais
- Univ Lyon, Université Claude Bernard Lyon 1, INSA-Lyon, CNRS, UMR5240 MAP, F-69622, France
| | - Georgi Muskhelishvili
- Agricultural University of Georgia, School of Natural Sciences, 0159 Tbilisi, Georgia
| | - William Nasser
- Univ Lyon, Université Claude Bernard Lyon 1, INSA-Lyon, CNRS, UMR5240 MAP, F-69622, France
| |
Collapse
|
22
|
Stanton E, Wahlig TA, Park D, Kaspar CW. Chronological set of E. coli O157:H7 bovine strains establishes a role for repeat sequences and mobile genetic elements in genome diversification. BMC Genomics 2020; 21:562. [PMID: 32807088 PMCID: PMC7430833 DOI: 10.1186/s12864-020-06943-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 07/23/2020] [Indexed: 11/21/2022] Open
Abstract
Background Enterohemorrhagic Escherichia coli O157:H7 (EHEC) is a significant foodborne pathogen that resides asymptomatically within cattle and other ruminants. The EHEC genome harbors an extensive collection of mobile genetic elements (MGE), including multiple prophage, prophage-like elements, plasmids, and insertion sequence (IS) elements. Results A chronological collection of EHEC strains (FRIK804, FRIK1275, and FRIK1625) isolated from a Wisconsin dairy farm (farm X) comprised a closely related clade genetically differentiated by structural alterations to the chromosome. Comparison of the FRIK804 genome with a reference EHEC strain Sakai found a unique prophage like element (PLE, indel 1) and an inversion (1.15 Mb) situated symmetrically with respect to the terminus region. Detailed analysis determined the inversion was due to homologous recombination between repeat sequences in prophage. The three farm X strains were distinguished by the presence or absence of indel 3 (61 kbp) and indel 4 (48 kbp); FRIK804 contained both of these regions, FRIK1275 lacked indel 4, and indels 3 and 4 were both absent in FRIK1625. Indel 3 was the stx2 prophage and indel 4 involved a deletion between two adjacent prophage with shared repeat sequences. Both FRIK804 and FRIK1275 produced functional phage while FRIK1625 did not, which is consistent with indel 3. Due to their involvement in recombination events, direct and inverted repeat sequences were identified, and their locations mapped to the chromosome. FRIK804 had a greater number and overall length of repeat sequences than E. coli K12 strain MG1655. Repeat sequences were most commonly associated with MGE. Conclusions This research demonstrated that three EHEC strains from a Wisconsin dairy farm were closely related and distinguished by variability within prophage regions and other MGE. Chromosome alterations were associated with recombination events between repeat sequences. An inventory of direct and inverted repeat sequences found a greater abundance and total length of repeat sequences in the EHEC strains compared to E. coli strain MG1655. The locations of the repeat sequences were biased towards MGE. The findings from this study expand our understanding of the precise molecular events and elements that contributed to genetic diversification of wild-type EHEC in the bovine and farm environments.
Collapse
Affiliation(s)
- Eliot Stanton
- Department of Bacteriology, University of Wisconsin-Madison, Microbial Sciences Building, 1550 Linden Drive, Madison, WI, 53706, USA
| | - Taylor A Wahlig
- Department of Bacteriology, University of Wisconsin-Madison, Microbial Sciences Building, 1550 Linden Drive, Madison, WI, 53706, USA.,University of Utah, School of Medicine, 30 N 1900 E, Salt Lake City, UT, 84132, USA
| | - Dongjin Park
- Food Science and Technology Department, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - Charles W Kaspar
- Department of Bacteriology, University of Wisconsin-Madison, Microbial Sciences Building, 1550 Linden Drive, Madison, WI, 53706, USA. .,Food Research Institute, University of Wisconsin-Madison, Microbial Sciences Building, 1550 Linden Drive, Madison, WI, 53706, USA.
| |
Collapse
|
23
|
The Concerted Action of Two B3-Like Prophage Genes Excludes Superinfecting Bacteriophages by Blocking DNA Entry into Pseudomonas aeruginosa. J Virol 2020; 94:JVI.00953-20. [PMID: 32461312 DOI: 10.1128/jvi.00953-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 05/15/2020] [Indexed: 12/15/2022] Open
Abstract
In this study, we describe seven vegetative phage genomes homologous to the historic phage B3 that infect Pseudomonas aeruginosa Like other phage groups, the B3-like group contains conserved (core) and variable (accessory) open reading frames (ORFs) grouped at fixed regions in their genomes; however, in either case, many ORFs remain without assigned functions. We constructed lysogens of the seven B3-like phages in strain Ps33 of P. aeruginosa, a novel clinical isolate, and assayed the exclusion phenotype against a variety of temperate and virulent superinfecting phages. In addition to the classic exclusion conferred by the phage immunity repressor, the phenotype observed in B3-like lysogens suggested the presence of other exclusion genes. We set out to identify the genes responsible for this exclusion phenotype. Phage Ps56 was chosen as the study subject since it excluded numerous temperate and virulent phages. Restriction of the Ps56 genome, cloning of several fragments, and resection of the fragments that retained the exclusion phenotype allowed us to identify two core ORFs, so far without any assigned function, as responsible for a type of exclusion. Neither gene expressed separately from plasmids showed activity, but the concurrent expression of both ORFs is needed for exclusion. Our data suggest that phage adsorption occurs but that phage genome translocation to the host's cytoplasm is defective. To our knowledge, this is the first report on this type of exclusion mediated by a prophage in P. aeruginosa IMPORTANCE Pseudomonas aeruginosa is a Gram-negative bacterium frequently isolated from infected immunocompromised patients, and the strains are resistant to a broad spectrum of antibiotics. Recently, the use of phages has been proposed as an alternative therapy against multidrug-resistant bacteria. However, this approach may present various hurdles. This work addresses the problem that pathogenic bacteria may be lysogenized by phages carrying genes encoding resistance against secondary infections, such as those used in phage therapy. Discovering phage genes that exclude superinfecting phages not only assigns novel functions to orphan genes in databases but also provides insight into selection of the proper phages for use in phage therapy.
Collapse
|
24
|
White RA, Visscher PT, Burns BP. Between a Rock and a Soft Place: The Role of Viruses in Lithification of Modern Microbial Mats. Trends Microbiol 2020; 29:204-213. [PMID: 32654857 DOI: 10.1016/j.tim.2020.06.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 06/07/2020] [Accepted: 06/16/2020] [Indexed: 12/22/2022]
Abstract
Stromatolites are geobiological systems formed by complex microbial communities, and fossilized stromatolites provide a record of some of the oldest life on Earth. Microbial mats are precursors of extant stromatolites; however, the mechanisms of transition from mat to stromatolite are controversial and are still not well understood. To fully recognize the profound impact that these ecosystems have had on the evolution of the biosphere requires an understanding of modern lithification mechanisms and how they relate to the geological record. We propose here viral mechanisms in carbonate precipitation, leading to stromatolite formation, whereby viruses directly or indirectly impact microbial metabolisms that govern the transition from microbial mat to stromatolite. Finding a tangible link between host-virus interactions and changes in biogeochemical processes will provide tools to interpret mineral biosignatures through geologic time, including those on Earth and beyond.
Collapse
Affiliation(s)
- Richard Allen White
- Plant Pathology, Washington State University, Pullman, WA, USA; Australian Centre for Astrobiology, University of New South Wales, Sydney, Australia; RAW Molecular Systems (RMS) LLC, Spokane, WA, USA
| | - Pieter T Visscher
- Australian Centre for Astrobiology, University of New South Wales, Sydney, Australia; Departments of Marine Sciences and Geosciences, University of Connecticut, CT, USA; Biogeosciences, the Université de Bourgogne Franche-Comté, Dijon, France
| | - Brendan P Burns
- Australian Centre for Astrobiology, University of New South Wales, Sydney, Australia; School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, Australia.
| |
Collapse
|
25
|
Walker DM, Freddolino PL, Harshey RM. A Well-Mixed E. coli Genome: Widespread Contacts Revealed by Tracking Mu Transposition. Cell 2020; 180:703-716.e18. [PMID: 32059782 DOI: 10.1016/j.cell.2020.01.031] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 10/21/2019] [Accepted: 01/22/2020] [Indexed: 02/06/2023]
Abstract
The three-dimensional structures of chromosomes are increasingly being recognized as playing a major role in cellular regulatory states. The efficiency and promiscuity of phage Mu transposition was exploited to directly measure in vivo interactions between genomic loci in E. coli. Two global organizing principles have emerged: first, the chromosome is well-mixed and uncompartmentalized, with transpositions occurring freely between all measured loci; second, several gene families/regions show "clustering": strong three-dimensional co-localization regardless of linear genomic distance. The activities of the SMC/condensin protein MukB and nucleoid-compacting protein subunit HU-α are essential for the well-mixed state; HU-α is also needed for clustering of 6/7 ribosomal RNA-encoding loci. The data are explained by a model in which the chromosomal structure is driven by dynamic competition between DNA replication and chromosomal relaxation, providing a foundation for determining how region-specific properties contribute to both chromosomal structure and gene regulation.
Collapse
Affiliation(s)
- David M Walker
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA
| | - Peter L Freddolino
- Department of Biological Chemistry and Department of Computational Medicine & Bioinformatics, University of Michigan, Ann Arbor, MI 48109, USA.
| | - Rasika M Harshey
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA.
| |
Collapse
|
26
|
Katashkina JI, Kazieva ED, Tajima Y, Mashko SV. Increased Isoprene Production by the Recombinant Pantoea ananatis Strain due to the Balanced Amplification of Mevalonate Pathway Genes. APPL BIOCHEM MICRO+ 2019. [DOI: 10.1134/s0003683819090023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
27
|
Rasila TS, Pulkkinen E, Kiljunen S, Haapa-Paananen S, Pajunen MI, Salminen A, Paulin L, Vihinen M, Rice PA, Savilahti H. Mu transpososome activity-profiling yields hyperactive MuA variants for highly efficient genetic and genome engineering. Nucleic Acids Res 2019; 46:4649-4661. [PMID: 29294068 PMCID: PMC5961161 DOI: 10.1093/nar/gkx1281] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 12/21/2017] [Indexed: 11/22/2022] Open
Abstract
The phage Mu DNA transposition system provides a versatile species non-specific tool for molecular biology, genetic engineering and genome modification applications. Mu transposition is catalyzed by MuA transposase, with DNA cleavage and integration reactions ultimately attaching the transposon DNA to target DNA. To improve the activity of the Mu DNA transposition machinery, we mutagenized MuA protein and screened for hyperactivity-causing substitutions using an in vivo assay. The individual activity-enhancing substitutions were mapped onto the MuA–DNA complex structure, containing a tetramer of MuA transposase, two Mu end segments and a target DNA. This analysis, combined with the varying effect of the mutations in different assays, implied that the mutations exert their effects in several ways, including optimizing protein–protein and protein–DNA contacts. Based on these insights, we engineered highly hyperactive versions of MuA, by combining several synergistically acting substitutions located in different subdomains of the protein. Purified hyperactive MuA variants are now ready for use as second-generation tools in a variety of Mu-based DNA transposition applications. These variants will also widen the scope of Mu-based gene transfer technologies toward medical applications such as human gene therapy. Moreover, the work provides a platform for further design of custom transposases.
Collapse
Affiliation(s)
- Tiina S Rasila
- Division of Genetics and Physiology, Department of Biology, FI-20014 University of Turku, Turku, Finland.,Institute of Biotechnology, Viikki Biocenter, P. O. Box 56, FI-00014 University of Helsinki, Helsinki, Finland
| | - Elsi Pulkkinen
- Division of Genetics and Physiology, Department of Biology, FI-20014 University of Turku, Turku, Finland
| | - Saija Kiljunen
- Division of Genetics and Physiology, Department of Biology, FI-20014 University of Turku, Turku, Finland
| | - Saija Haapa-Paananen
- Division of Genetics and Physiology, Department of Biology, FI-20014 University of Turku, Turku, Finland
| | - Maria I Pajunen
- Division of Biochemistry and Biotechnology, Department of Biosciences, FI-00014 University of Helsinki, Helsinki, Finland
| | - Anu Salminen
- Department of Biochemistry, FI-20014 University of Turku, Turku, Finland
| | - Lars Paulin
- Institute of Biotechnology, Viikki Biocenter, P. O. Box 56, FI-00014 University of Helsinki, Helsinki, Finland
| | - Mauno Vihinen
- Department of Experimental Medical Science, Lund University, SE-221 84, Lund, Sweden
| | - Phoebe A Rice
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637, USA
| | - Harri Savilahti
- Division of Genetics and Physiology, Department of Biology, FI-20014 University of Turku, Turku, Finland.,Institute of Biotechnology, Viikki Biocenter, P. O. Box 56, FI-00014 University of Helsinki, Helsinki, Finland
| |
Collapse
|
28
|
Flores-Ríos R, Quatrini R, Loyola A. Endogenous and Foreign Nucleoid-Associated Proteins of Bacteria: Occurrence, Interactions and Effects on Mobile Genetic Elements and Host's Biology. Comput Struct Biotechnol J 2019; 17:746-756. [PMID: 31303979 PMCID: PMC6606824 DOI: 10.1016/j.csbj.2019.06.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 06/05/2019] [Accepted: 06/11/2019] [Indexed: 02/08/2023] Open
Abstract
Mobile Genetic Elements (MGEs) are mosaics of functional gene modules of diverse evolutionary origin and are generally divergent from the hosts´ genetic background. Existing biases in base composition and codon usage of these elements` genes impose transcription and translation limitations that may affect the physical and regulatory integration of MGEs in new hosts. Stable appropriation of the foreign DNA depends on a number of host factors among which are the Nucleoid-Associated Proteins (NAPs). These small, basic, highly abundant proteins bind and bend DNA, altering its topology and folding, thereby affecting all known essential DNA metabolism related processes. Both chromosomally- (endogenous) and MGE- (foreign) encoded NAPs have been shown to exist in bacteria. While the role of host-encoded NAPs in xenogeneic silencing of both episomal (plasmids) and integrative MGEs (pathogenicity islands and prophages) is well acknowledged, less is known about the role of MGE-encoded NAPs in the foreign elements biology or their influence on the host's chromosome expression dynamics. Here we review existing literature on the topic, present examples on the positive and negative effects that endogenous and foreign NAPs exert on global transcriptional gene expression, MGE integrative and excisive recombination dynamics, persistence and transfer to suitable hosts and discuss the nature and relevance of synergistic and antagonizing higher order interactions between diverse types of NAPs.
Collapse
Affiliation(s)
| | - Raquel Quatrini
- Fundación Ciencia y Vida, Avenida Zañartu 1482, Ñuñoa, Santiago, Chile.,Millennium Nucleus in the Biology of Intestinal Microbiota, Santiago, Chile
| | - Alejandra Loyola
- Fundación Ciencia y Vida, Avenida Zañartu 1482, Ñuñoa, Santiago, Chile
| |
Collapse
|
29
|
Galetti R, Andrade LN, Varani AM, Darini ALC. A Phage-Like Plasmid Carrying bla KPC-2 Gene in Carbapenem-Resistant Pseudomonas aeruginosa. Front Microbiol 2019; 10:572. [PMID: 30949157 PMCID: PMC6435834 DOI: 10.3389/fmicb.2019.00572] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 03/05/2019] [Indexed: 11/29/2022] Open
Abstract
Background: Lateral gene transfer plays a central role in the dissemination of carbapenem resistance in bacterial pathogens associated with nosocomial infections, mainly Enterobacteriaceae and Pseudomonas aeruginosa. Despite their clinical significance, there is little information regarding the mobile genetic elements and mechanism of acquisition and propagation of lateral genes in P. aeruginosa, and they remain largely unknown. Objectives: The present study characterized the genetic context of bla KPC-2 in carbapenem-resistant P. aeruginosa strain BH9. Methods: Pseudomonas aeruginosa BH9 sequencing was performed using the long-read PacBio SMRT platform and the Ion Proton System. De novo assembly was carried out using the SMRT pipeline and Canu, and gene prediction and annotation were performed using Prokka and RAST. Results: Pseudomonas aeruginosa BH9 exhibited a 7.1 Mb circular chromosome. However, the bla KPC-2 gene is located in an additional contig composed by a small plasmid pBH6 from P. aeruginosa strain BH6 and several phage-related genes. Further analysis revealed that the beginning and end of the contig contain identical sequences, supporting a circular plasmid structure. This structure spans 41,087 bp, exhibiting all the Mu-like phage landmarks. In addition, 5-bp direct repeats (GGATG) flanking the pBH6 ends were found, strongly indicating integration of the Mu-like phage into the pBH6 plasmid. Mu phages are commonly found in P. aeruginosa. However, for the first time showing a potential impact in shaping the vehicles of the dissemination of antimicrobial (e.g., plasmid pBH6) resistance genes in the Pseudomonas genus. Conclusion: pBH6 captured the Mu-like Phage BH9, creating a co-integrate pBH6::Phage BH9, and this phage-plasmid complex may represent novel case of a phage-like plasmid.
Collapse
Affiliation(s)
- Renata Galetti
- School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - Leonardo Neves Andrade
- School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - Alessandro M. Varani
- School of Agricultural and Veterinary Studies, São Paulo State University “Julio de Mesquita Filho” (UNESP), Jaboticabal, Brazil
| | - Ana Lúcia Costa Darini
- School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| |
Collapse
|
30
|
Uhrynowski W, Radlinska M, Drewniak L. Genomic Analysis of Shewanella sp. O23S-The Natural Host of the pSheB Plasmid Carrying Genes for Arsenic Resistance and Dissimilatory Reduction. Int J Mol Sci 2019; 20:ijms20051018. [PMID: 30813619 PMCID: PMC6429310 DOI: 10.3390/ijms20051018] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 02/20/2019] [Accepted: 02/21/2019] [Indexed: 02/05/2023] Open
Abstract
Shewanella sp. O23S is a dissimilatory arsenate reducing bacterial strain involved in arsenic transformations within the abandoned gold mine in Zloty Stok (SW Poland). Previous physiological studies revealed that O23S may not only release arsenic from minerals, but also facilitate its immobilization through co-precipitation with reduced sulfur species. Given these uncommon, complementary characteristics and the application potential of the strain in arsenic-removal technologies, its genome (~5.3 Mbp), consisting of a single chromosome, two large plasmids (pSheA and pSheB) and three small plasmid-like phages (pSheC-E) was sequenced and annotated. Genes encoding putative proteins involved in heavy metal transformations, antibiotic resistance and other phenotypic traits were identified. An in-depth comparative analysis of arsenic respiration (arr) and resistance (ars) genes and their genetic context was also performed, revealing that pSheB carries the only copy of the arr genes, and a complete ars operon. The plasmid pSheB is therefore a unique natural vector of these genes, providing the host cells arsenic respiration and resistance abilities. The functionality of the identified genes was determined based on the results of the previous and additional physiological studies, including: the assessment of heavy metal and antibiotic resistance under various conditions, adhesion-biofilm formation assay and BiologTM metabolic preferences test. This combined genetic and physiological approach shed a new light on the capabilities of O23S and their molecular basis, and helped to confirm the biosafety of the strain in relation to its application in bioremediation technologies.
Collapse
Affiliation(s)
- Witold Uhrynowski
- Laboratory of Environmental Pollution Analysis, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland.
| | - Monika Radlinska
- Department of Virology, Institute of Microbiology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland.
| | - Lukasz Drewniak
- Laboratory of Environmental Pollution Analysis, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland.
| |
Collapse
|
31
|
Ramisetty BCM, Sudhakari PA. Bacterial 'Grounded' Prophages: Hotspots for Genetic Renovation and Innovation. Front Genet 2019; 10:65. [PMID: 30809245 PMCID: PMC6379469 DOI: 10.3389/fgene.2019.00065] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Accepted: 01/24/2019] [Indexed: 01/07/2023] Open
Abstract
Bacterial genomes are highly plastic allowing the generation of variants through mutations and acquisition of genetic information. The fittest variants are then selected by the econiche thereby allowing the bacterial adaptation and colonization of the habitat. Larger genomes, however, may impose metabolic burden and hence bacterial genomes are optimized by the loss of frivolous genetic information. The activity of temperate bacteriophages has acute consequences on the bacterial population as well as the bacterial genome through lytic and lysogenic cycles. Lysogeny is a selective advantage as the prophage provides immunity to the lysogen against secondary phage attack. Since the non-lysogens are eliminated by the lytic phages, lysogens multiply and colonize the habitat. Nevertheless, all lysogens have an imminent risk of lytic cycle activation and cell lysis. However, a mutation in the attachment sites or in the genes that encode the specific recombinase responsible for prophage excision could result in 'grounding' of the prophage. Since the lysogens with grounded prophage are immune to respective phage infection as well as dodge the induction of lytic cycle, we hypothesize that the selection of these mutant lysogens is favored relative to their normal lysogenic counterparts. These grounded prophages offer several advantages to the bacterial genome evolution through propensity for genetic variations including inversions, deletions, and insertions via horizontal gene transfer. We propose that the grounded prophages expedite bacterial genome evolution by acting as 'genetic buffer zones' thereby increasing the frequency as well as the diversity of variations on which natural selection favors the beneficial variants. The grounded prophages are also hotspots for horizontal gene transfer wherein several ecologically significant genes such as those involved in stress tolerance, antimicrobial resistance, and novel metabolic pathways, are integrated. Moreover, the high frequency of genetic changes within prophages also allows proportionate probability for the de novo genesis of genetic information. Through sequence analyses of well-characterized E. coli prophages we exemplify various roles of grounded prophages in E. coli ecology and evolution. Therefore, the temperate prophages are one of the most significant drivers of bacterial genome evolution and sites of biogenesis of genetic information.
Collapse
Affiliation(s)
- Bhaskar Chandra Mohan Ramisetty
- Laboratory of Molecular Biology and Evolution, School of Chemical and Biotechnology, SASTRA Deemed University, Thanjavur, India
| | - Pavithra Anantharaman Sudhakari
- Laboratory of Molecular Biology and Evolution, School of Chemical and Biotechnology, SASTRA Deemed University, Thanjavur, India
| |
Collapse
|
32
|
Kotlajich MV, Xia J, Zhai Y, Lin HY, Bradley CC, Shen X, Mei Q, Wang AZ, Lynn EJ, Shee C, Chen LT, Li L, Miller KM, Herman C, Hastings PJ, Rosenberg SM. Fluorescent fusions of the N protein of phage Mu label DNA damage in living cells. DNA Repair (Amst) 2018; 72:86-92. [PMID: 30268364 PMCID: PMC6287932 DOI: 10.1016/j.dnarep.2018.09.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Revised: 09/09/2018] [Accepted: 09/10/2018] [Indexed: 01/06/2023]
Abstract
The N protein of phage Mu was indicated from studies in Escherichia coli to hold linear Mu chromosomes in a circular conformation by non-covalent association, and thus suggested potentially to bind DNA double-stranded ends. Because of its role in association with linear Mu DNA, we tested whether fluorescent-protein fusions to N might provide a useful tool for labeling DNA damage including double-strand break (DSB) ends in single cells. We compared N-GFP with a biochemically well documented DSB-end binding protein, the Gam protein of phage Mu, also fused to GFP. We find that N-GFP produced in live E. coli forms foci in response to DNA damage induced by radiomimetic drug phleomycin, indicating that it labels damaged DNA. N-GFP also labels specific DSBs created enzymatically by I-SceI double-strand endonuclease, and by X-rays, with the numbers of foci corresponding with the numbers of DSBs generated, indicating DSB labeling. However, whereas N-GFP forms about half as many foci as GamGFP with phleomycin, its labeling of I-SceI- and X-ray-induced DSBs is far less efficient than that of GamGFP. The data imply that N-GFP binds and labels DNA damage including DSBs, but may additionally label phleomycin-induced non-DSB damage, with which DSB-specific GamGFP does not interact. The data indicate that N-GFP labels DNA damage, and may be useful for general, not DSB-specific, DNA-damage detection.
Collapse
Affiliation(s)
- Matthew V Kotlajich
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA; Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030, USA; Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas 77030, USA; Dan L Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Jun Xia
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA; Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030, USA; Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas 77030, USA; Dan L Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Yin Zhai
- Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030, USA; Dan L Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Hsin-Yu Lin
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA; Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030, USA; Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas 77030, USA; Dan L Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Catherine C Bradley
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA; Medical Scientist Training Program, Baylor College of Medicine, Houston, Texas 77030, USA; Robert and Janice McNair Foundation/McNair Medical Institute M.D./Ph.D. Scholars Program, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Xi Shen
- Department of Experimental Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA
| | - Qian Mei
- Dan L Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, Texas 77030, USA; Systems, Synthetic and Physical Biology Program, Rice University, Houston, Texas 77030, USA
| | - Anthony Z Wang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA; Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030, USA; Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas 77030, USA; Dan L Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Erica J Lynn
- Department of Experimental Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA
| | - Chandan Shee
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA; Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030, USA; Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas 77030, USA; Dan L Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Li-Tzu Chen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA; Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030, USA; Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas 77030, USA; Dan L Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Lei Li
- Department of Experimental Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA
| | - Kyle M Miller
- Dan L Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, Texas 77030, USA; Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, Texas 78712 USA
| | - Christophe Herman
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA; Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas 77030, USA; Dan L Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, Texas 77030, USA
| | - P J Hastings
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA; Dan L Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Susan M Rosenberg
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA; Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030, USA; Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas 77030, USA; Dan L Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, Texas 77030, USA; Systems, Synthetic and Physical Biology Program, Rice University, Houston, Texas 77030, USA.
| |
Collapse
|
33
|
Keen EC, Dantas G. Close Encounters of Three Kinds: Bacteriophages, Commensal Bacteria, and Host Immunity. Trends Microbiol 2018; 26:943-954. [PMID: 29909042 PMCID: PMC6436384 DOI: 10.1016/j.tim.2018.05.009] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 05/08/2018] [Accepted: 05/17/2018] [Indexed: 12/22/2022]
Abstract
Recent years have witnessed an explosion of interest in the human microbiota. Although commensal bacteria have dominated research efforts to date, mounting evidence suggests that endogenous viral populations (the 'virome') play key roles in basic human physiology. The most numerous constituents of the human virome are not eukaryotic viruses but rather bacteriophages, viruses that infect bacteria. Here, we review phages' interactions with their immediate (prokaryotic) and extended (eukaryotic) hosts and with each other, with a particular emphasis on the temperate phages and prophages which dominate the human virome. We also discuss key outstanding questions in this emerging field and emphasize the urgent need for functional studies in animal models to complement previous in vitro work and current computational approaches.
Collapse
Affiliation(s)
- Eric C Keen
- The Edison Family Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO, USA.
| | - Gautam Dantas
- The Edison Family Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO, USA; Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA; Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO, USA; Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO, USA.
| |
Collapse
|
34
|
Chen W, Mandali S, Hancock SP, Kumar P, Collazo M, Cascio D, Johnson RC. Multiple serine transposase dimers assemble the transposon-end synaptic complex during IS 607-family transposition. eLife 2018; 7:39611. [PMID: 30289389 PMCID: PMC6188088 DOI: 10.7554/elife.39611] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 09/18/2018] [Indexed: 11/13/2022] Open
Abstract
IS607-family transposons are unusual because they do not have terminal inverted repeats or generate target site duplications. They encode two protein-coding genes, but only tnpA is required for transposition. Our X-ray structures confirm that TnpA is a member of the serine recombinase (SR) family, but the chemically-inactive quaternary structure of the dimer, along with the N-terminal location of the DNA binding domain, are different from other SRs. TnpA dimers from IS1535 cooperatively associate with multiple subterminal repeats, which together with additional nonspecific binding, form a nucleoprotein filament on one transposon end that efficiently captures a second unbound end to generate the paired-end complex (PEC). Formation of the PEC does not require a change in the dimeric structure of the catalytic domain, but remodeling of the C-terminal α-helical region is involved. We posit that the PEC recruits a chemically-active conformer of TnpA to the transposon end to initiate DNA chemistry.
Collapse
Affiliation(s)
- Wenyang Chen
- Department of Biological Chemistry, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, United States
| | - Sridhar Mandali
- Department of Biological Chemistry, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, United States
| | - Stephen P Hancock
- Department of Biological Chemistry, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, United States
| | - Pramod Kumar
- Department of Biological Chemistry, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, United States
| | - Michael Collazo
- Department of Energy Institute of Genomics and Proteomics, University of California at Los Angeles, Los Angeles, United States
| | - Duilio Cascio
- Department of Energy Institute of Genomics and Proteomics, University of California at Los Angeles, Los Angeles, United States
| | - Reid C Johnson
- Department of Biological Chemistry, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, United States.,Molecular Biology Institute, University of California at Los Angeles, Los Angeles, United States
| |
Collapse
|
35
|
Babakhani S, Oloomi M. Transposons: the agents of antibiotic resistance in bacteria. J Basic Microbiol 2018; 58:905-917. [PMID: 30113080 DOI: 10.1002/jobm.201800204] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 07/08/2018] [Accepted: 07/31/2018] [Indexed: 12/29/2022]
Abstract
Transposons are a group of mobile genetic elements that are defined as a DNA sequence. Transposons can jump into different places of the genome; for this reason, they are called jumping genes. However, some transposons are always kept at the insertion site in the genome. Most transposons are inactivated and as a result, cannot move. Transposons are divided into two main groups: retrotransposons (class І) and DNA transposons (class ІІ). Retrotransposons are often found in eukaryotes. DNA transposons can be found in both eukaryotes and prokaryotes. The bacterial transposons belong to the DNA transposons and the Tn family, which are usually the carrier of additional genes for antibiotic resistance. Transposons can transfer from a plasmid to other plasmids or from a DNA chromosome to plasmid and vice versa that cause the transmission of antibiotic resistance genes in bacteria. The treatment of bacterial infectious diseases is difficult because of existing antibiotic resistance that part of this antibiotic resistance is caused by transposons. Bacterial infectious diseases are responsible for the increasing rise in world mortality rate. In this review, transposons and their roles have been studied in bacterial antibiotic resistance, in detail.
Collapse
Affiliation(s)
- Sajad Babakhani
- Department of Microbiology, North Tehran Branch, Islamic Azad University, Tehran, Iran
| | - Mana Oloomi
- Department of Molecular Biology, Pasteur Institute of Iran, Tehran, Iran
| |
Collapse
|
36
|
Vergnaud G, Midoux C, Blouin Y, Bourkaltseva M, Krylov V, Pourcel C. Transposition Behavior Revealed by High-Resolution Description of Pseudomonas Aeruginosa Saltovirus Integration Sites. Viruses 2018; 10:v10050245. [PMID: 29735891 PMCID: PMC5977238 DOI: 10.3390/v10050245] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 04/27/2018] [Accepted: 05/04/2018] [Indexed: 01/08/2023] Open
Abstract
Transposable phages, also called saltoviruses, of which the Escherichia coli phage Mu is the reference, are temperate phages that multiply their genome through replicative transposition at multiple sites in their host chromosome. The viral genome is packaged together with host DNA at both ends. In the present work, genome sequencing of three Pseudomonas aeruginosa transposable phages, HW12, 2P1, and Ab30, incidentally gave us access to the location of thousands of replicative integration sites and revealed the existence of a variable number of hotspots. Taking advantage of deep sequencing, we then designed an experiment to study 13,000,000 transposon integration sites of bacteriophage Ab30. The investigation revealed the presence of 42 transposition hotspots adjacent to bacterial interspersed mosaic elements (BIME) accounting for 5% of all transposition sites. The rest of the sites appeared widely distributed with the exception of coldspots associated with low G-C content segments, including the putative O-antigen biosynthesis cluster. Surprisingly, 0.4% of the transposition events occurred in a copy of the phage genome itself, indicating that the previously described immunity against such events is slightly leaky. This observation allowed drawing an image of the phage chromosome supercoiling into four loops.
Collapse
Affiliation(s)
- Gilles Vergnaud
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette CEDEX, France.
| | - Cédric Midoux
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette CEDEX, France.
| | - Yann Blouin
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette CEDEX, France.
| | - Maria Bourkaltseva
- I. I. Mechnikov Research Institute for Vaccines & Sera, Moscow 105064, Russia.
| | - Victor Krylov
- I. I. Mechnikov Research Institute for Vaccines & Sera, Moscow 105064, Russia.
| | - Christine Pourcel
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette CEDEX, France.
| |
Collapse
|
37
|
Gorshkova NV, Lobanova JS, Tokmakova IL, Smirnov SV, Akhverdyan VZ, Krylov AA, Mashko SV. Mu-driven transposition of recombinant mini-Mu unit DNA in the Corynebacterium glutamicum chromosome. Appl Microbiol Biotechnol 2018; 102:2867-2884. [PMID: 29392386 PMCID: PMC5847225 DOI: 10.1007/s00253-018-8767-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 01/03/2018] [Accepted: 01/04/2018] [Indexed: 02/05/2023]
Abstract
A dual-component Mu-transposition system was modified for the integration/amplification of genes in Corynebacterium. The system consists of two types of plasmids: (i) a non-replicative integrative plasmid that contains the transposing mini-Mu(LR) unit bracketed by the L/R Mu ends or the mini-Mu(LER) unit, which additionally contains the enhancer element, E, and (ii) an integration helper plasmid that expresses the transposition factor genes for MuA and MuB. Efficient transposition in the C. glutamicum chromosome (≈ 2 × 10−4 per cell) occurred mainly through the replicative pathway via cointegrate formation followed by possible resolution. Optimizing the E location in the mini-Mu unit significantly increased the efficiency of Mu-driven intramolecular transposition–amplification in C. glutamicum as well as in gram-negative bacteria. The new C. glutamicum genome modification strategy that was developed allows the consequent independent integration/amplification/fixation of target genes at high copy numbers. After integration/amplification of the first mini-Mu(LER) unit in the C. glutamicum chromosome, the E-element, which is bracketed by lox-like sites, is excised by Cre-mediated fashion, thereby fixing the truncated mini-Mu(LR) unit in its position for the subsequent integration/amplification of new mini-Mu(LER) units. This strategy was demonstrated using the genes for the citrine and green fluorescent proteins, yECitrine and yEGFP, respectively.
Collapse
Affiliation(s)
- Natalya V Gorshkova
- Ajinomoto-Genetika Research Institute, 1-st Dorozhny proezd, 1-1, Moscow, Russian Federation, 117545
| | - Juliya S Lobanova
- Ajinomoto-Genetika Research Institute, 1-st Dorozhny proezd, 1-1, Moscow, Russian Federation, 117545
| | - Irina L Tokmakova
- Ajinomoto-Genetika Research Institute, 1-st Dorozhny proezd, 1-1, Moscow, Russian Federation, 117545
| | - Sergey V Smirnov
- Ajinomoto-Genetika Research Institute, 1-st Dorozhny proezd, 1-1, Moscow, Russian Federation, 117545
| | - Valerii Z Akhverdyan
- Ajinomoto-Genetika Research Institute, 1-st Dorozhny proezd, 1-1, Moscow, Russian Federation, 117545
| | - Alexander A Krylov
- Ajinomoto-Genetika Research Institute, 1-st Dorozhny proezd, 1-1, Moscow, Russian Federation, 117545
| | - Sergey V Mashko
- Ajinomoto-Genetika Research Institute, 1-st Dorozhny proezd, 1-1, Moscow, Russian Federation, 117545.
| |
Collapse
|
38
|
Rai SK, Sangesland M, Lee M, Esnault C, Cui Y, Chatterjee AG, Levin HL. Host factors that promote retrotransposon integration are similar in distantly related eukaryotes. PLoS Genet 2017; 13:e1006775. [PMID: 29232693 PMCID: PMC5741268 DOI: 10.1371/journal.pgen.1006775] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 12/22/2017] [Accepted: 11/07/2017] [Indexed: 12/14/2022] Open
Abstract
Retroviruses and Long Terminal Repeat (LTR)-retrotransposons have distinct patterns of integration sites. The oncogenic potential of retrovirus-based vectors used in gene therapy is dependent on the selection of integration sites associated with promoters. The LTR-retrotransposon Tf1 of Schizosaccharomyces pombe is studied as a model for oncogenic retroviruses because it integrates into the promoters of stress response genes. Although integrases (INs) encoded by retroviruses and LTR-retrotransposons are responsible for catalyzing the insertion of cDNA into the host genome, it is thought that distinct host factors are required for the efficiency and specificity of integration. We tested this hypothesis with a genome-wide screen of host factors that promote Tf1 integration. By combining an assay for transposition with a genetic assay that measures cDNA recombination we could identify factors that contribute differentially to integration. We utilized this assay to test a collection of 3,004 S. pombe strains with single gene deletions. Using these screens and immunoblot measures of Tf1 proteins, we identified a total of 61 genes that promote integration. The candidate integration factors participate in a range of processes including nuclear transport, transcription, mRNA processing, vesicle transport, chromatin structure and DNA repair. Two candidates, Rhp18 and the NineTeen complex were tested in two-hybrid assays and were found to interact with Tf1 IN. Surprisingly, a number of pathways we identified were found previously to promote integration of the LTR-retrotransposons Ty1 and Ty3 in Saccharomyces cerevisiae, indicating the contribution of host factors to integration are common in distantly related organisms. The DNA repair factors are of particular interest because they may identify the pathways that repair the single stranded gaps flanking the sites of strand transfer following integration of LTR retroelements. Retroviruses and retrotransposons are genetic elements that propagate by integrating into chromosomes of eukaryotic cells. Genetic disorders are being treated with retrovirus-based vectors that integrate corrective genes into the chromosomes of patients. Unfortunately, the vectors can alter expression of adjacent genes and depending on the position of integration, cancer genes can be induced. It is therefore essential that we understand how integration sites are selected. Interestingly, different retroviruses and retrotransposons have different profiles of integration sites. While specific proteins have been identified that select target sites, it’s not known what other cellular factors promote integration. In this paper, we report a comprehensive screen of host factors that promote LTR-retrotransposon integration in the widely-studied yeast, Schizosaccharomyces pombe. Unexpectedly, we found a wide range of pathways and host factors participate in integration. And importantly, we found the cellular processes that promote integration relative to recombination in S. pombe are the same that drive integration of LTR-retrotransposons in the distantly related yeast Saccharomyces cerevisiae. This suggests a specific set of cellular pathways are responsible for integration in a wide range of eukaryotic hosts.
Collapse
Affiliation(s)
- Sudhir Kumar Rai
- Section on Eukaryotic Transposable Elements, Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health (NIH), Bethesda, Maryland, United States of America
| | - Maya Sangesland
- Section on Eukaryotic Transposable Elements, Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health (NIH), Bethesda, Maryland, United States of America
| | - Michael Lee
- Section on Eukaryotic Transposable Elements, Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health (NIH), Bethesda, Maryland, United States of America
| | - Caroline Esnault
- Section on Eukaryotic Transposable Elements, Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health (NIH), Bethesda, Maryland, United States of America
| | - Yujin Cui
- Section on Eukaryotic Transposable Elements, Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health (NIH), Bethesda, Maryland, United States of America
| | - Atreyi Ghatak Chatterjee
- Section on Eukaryotic Transposable Elements, Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health (NIH), Bethesda, Maryland, United States of America
| | - Henry L. Levin
- Section on Eukaryotic Transposable Elements, Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health (NIH), Bethesda, Maryland, United States of America
- * E-mail:
| |
Collapse
|
39
|
Claeys Bouuaert C, Chalmers R. A single active site in the mariner transposase cleaves DNA strands of opposite polarity. Nucleic Acids Res 2017; 45:11467-11478. [PMID: 29036477 PMCID: PMC5714172 DOI: 10.1093/nar/gkx826] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2017] [Accepted: 09/08/2017] [Indexed: 01/01/2023] Open
Abstract
The RNase H structural fold defines a large family of nucleic acid metabolizing enzymes that catalyze phosphoryl transfer reactions using two divalent metal ions in the active site. Almost all of these reactions involve only one strand of the nucleic acid substrates. In contrast, cut-and-paste transposases cleave two DNA strands of opposite polarity, which is usually achieved via an elegant hairpin mechanism. In the mariner transposons, the hairpin intermediate is absent and key aspects of the mechanism by which the transposon ends are cleaved remained unknown. Here, we characterize complexes involved prior to catalysis, which define an asymmetric pathway for transpososome assembly. Using mixtures of wild-type and catalytically inactive transposases, we show that all the catalytic steps of transposition occur within the context of a dimeric transpososome. Crucially, we find that each active site of a transposase dimer is responsible for two hydrolysis and one transesterification reaction at the same transposon end. These results provide the first strong evidence that a DDE/D active site can hydrolyze DNA strands of opposite polarity, a mechanism that has rarely been observed with any type of nuclease.
Collapse
Affiliation(s)
- Corentin Claeys Bouuaert
- School of Biomedical Sciences, University of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, UK
| | - Ronald Chalmers
- School of Biomedical Sciences, University of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, UK
| |
Collapse
|
40
|
Tardin C. The mechanics of DNA loops bridged by proteins unveiled by single-molecule experiments. Biochimie 2017; 142:80-92. [PMID: 28804000 DOI: 10.1016/j.biochi.2017.08.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 08/06/2017] [Indexed: 12/28/2022]
Abstract
Protein-induced DNA bridging and looping is a common mechanism for various and essential processes in bacterial chromosomes. This mechanism is preserved despite the very different bacterial conditions and their expected influence on the thermodynamic and kinetic characteristics of the bridge formation and stability. Over the last two decades, single-molecule techniques carried out on in vitro DNA systems have yielded valuable results which, in combination with theoretical works, have clarified the effects of different parameters of nucleoprotein complexes on the protein-induced DNA bridging and looping process. In this review, I will outline the features that can be measured for such processes with various single-molecule techniques in use in the field. I will then describe both the experimental results and the theoretical models that illuminate the contribution of the DNA molecule itself as well as that of the bridging proteins in the DNA looping mechanism at play in the nucleoid of E. coli.
Collapse
Affiliation(s)
- Catherine Tardin
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, France.
| |
Collapse
|
41
|
Humayun MZ, Zhang Z, Butcher AM, Moshayedi A, Saier MH. Hopping into a hot seat: Role of DNA structural features on IS5-mediated gene activation and inactivation under stress. PLoS One 2017; 12:e0180156. [PMID: 28666002 PMCID: PMC5493358 DOI: 10.1371/journal.pone.0180156] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 06/09/2017] [Indexed: 11/30/2022] Open
Abstract
Insertion sequence elements (IS elements) are proposed to play major roles in shaping the genetic and phenotypic landscapes of prokaryotic cells. Recent evidence has raised the possibility that environmental stress conditions increase IS hopping into new sites, and often such hopping has the phenotypic effect of relieving the stress. Although stress-induced targeted mutations have been reported for a number of E. coli genes, the glpFK (glycerol utilization) and the cryptic bglGFB (β-glucoside utilization) systems are among the best characterized where the effects of IS insertion-mediated gene activation are well-characterized at the molecular level. In the glpFK system, starvation of cells incapable of utilizing glycerol leads to an IS5 insertion event that activates the glpFK operon, and enables glycerol utilization. In the case of the cryptic bglGFB operon, insertion of IS5 (and other IS elements) into a specific region in the bglG upstream sequence has the effect of activating the operon in both growing cells, and in starving cells. However, a major unanswered question in the glpFK system, the bgl system, as well as other examples, has been why the insertion events are promoted at specific locations, and how the specific stress condition (glycerol starvation for example) can be mechanistically linked to enhanced insertion at a specific locus. In this paper, we show that a specific DNA structural feature (superhelical stress-induced duplex destabilization, SIDD) is associated with "stress-induced" IS5 insertion in the glpFK, bglGFB, flhDC, fucAO and nfsB systems. We propose a speculative mechanistic model that links specific environmental conditions to the unmasking of an insertional hotspot in the glpFK system. We demonstrate that experimentally altering the predicted stability of a SIDD element in the nfsB gene significantly impacts IS5 insertion at its hotspot.
Collapse
Affiliation(s)
- M. Zafri Humayun
- Department of Microbiology, Biochemistry & Molecular Genetics, Rutgers—New Jersey Medical School, Newark, NJ, United States of America
| | - Zhongge Zhang
- Department of Molecular Biology, Division of Biological Sciences, University of California San Diego, La Jolla, CA, United States of America
| | - Anna M. Butcher
- Department of Molecular Biology, Division of Biological Sciences, University of California San Diego, La Jolla, CA, United States of America
| | - Aref Moshayedi
- Department of Molecular Biology, Division of Biological Sciences, University of California San Diego, La Jolla, CA, United States of America
| | - Milton H. Saier
- Department of Molecular Biology, Division of Biological Sciences, University of California San Diego, La Jolla, CA, United States of America
| |
Collapse
|
42
|
Lysogeny in nature: mechanisms, impact and ecology of temperate phages. ISME JOURNAL 2017; 11:1511-1520. [PMID: 28291233 DOI: 10.1038/ismej.2017.16] [Citation(s) in RCA: 386] [Impact Index Per Article: 55.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 12/04/2016] [Accepted: 01/19/2017] [Indexed: 01/07/2023]
Abstract
Viruses that infect bacteria (phages) can influence bacterial community dynamics, bacterial genome evolution and ecosystem biogeochemistry. These influences differ depending on whether phages establish lytic, chronic or lysogenic infections. Although the first two produce virion progeny, with lytic infections resulting in cell destruction, phages undergoing lysogenic infections replicate with cells without producing virions. The impacts of lysogeny are numerous and well-studied at the cellular level, but ecosystem-level consequences remain underexplored compared to those of lytic infections. Here, we review lysogeny from molecular mechanisms to ecological patterns to emerging approaches of investigation. Our goal is to highlight both its diversity and importance in complex communities. Altogether, using a combined viral ecology toolkit that is applied across broad model systems and environments will help us understand more of the diverse lifestyles and ecological impacts of lysogens in nature.
Collapse
|
43
|
Unlocking Tn3-family transposase activity in vitro unveils an asymetric pathway for transposome assembly. Proc Natl Acad Sci U S A 2017; 114:E669-E678. [PMID: 28096365 DOI: 10.1073/pnas.1611701114] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The Tn3 family is a widespread group of replicative transposons that are notorious for their contribution to the dissemination of antibiotic resistance and the emergence of multiresistant pathogens worldwide. The TnpA transposase of these elements catalyzes DNA breakage and rejoining reactions required for transposition. It also is responsible for target immunity, a phenomenon that prevents multiple insertions of the transposon into the same genomic region. However, the molecular mechanisms whereby TnpA acts in both processes remain unknown. Here, we have developed sensitive biochemical assays for the TnpA transposase of the Tn3-family transposon Tn4430 and used these assays to characterize previously isolated TnpA mutants that are selectively affected in immunity. Compared with wild-type TnpA, these mutants exhibit deregulated activities. They spontaneously assemble a unique asymmetric synaptic complex in which one TnpA molecule simultaneously binds two transposon ends. In this complex, TnpA is in an activated state competent for DNA cleavage and strand transfer. Wild-type TnpA can form this complex only on precleaved ends mimicking the initial step of transposition. The data suggest that transposition is controlled at an early stage of transpososome assembly, before DNA cleavage, and that mutations affecting immunity have unlocked TnpA by stabilizing the protein in a monomeric activated synaptic configuration. We propose an asymmetric pathway for coupling active transpososome assembly with proper target recruitment and discuss this model with respect to possible immunity mechanisms.
Collapse
|
44
|
Patel S. Drivers of bacterial genomes plasticity and roles they play in pathogen virulence, persistence and drug resistance. INFECTION GENETICS AND EVOLUTION 2016; 45:151-164. [DOI: 10.1016/j.meegid.2016.08.030] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 08/26/2016] [Accepted: 08/27/2016] [Indexed: 12/11/2022]
|
45
|
Berg DE. Julian Davies and the discovery of kanamycin resistance transposon Tn5. J Antibiot (Tokyo) 2016; 70:339-346. [PMID: 27731334 DOI: 10.1038/ja.2016.120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Revised: 08/28/2016] [Accepted: 08/31/2016] [Indexed: 11/09/2022]
Abstract
This paper recounts some of my fond memories of a collaboration between Julian Davies and myself that started in 1974 in Geneva and that led to our serendipitous discovery of the bacterial kanamycin resistance transposon Tn5, and aspects of the lasting positive impact of our interaction and discovery on me and the community. Tn5 was one of the first antibiotic resistance transposons to be found. Its analysis over the ensuing decades provided valuable insights into mechanisms and control of transposition, and led to its use as a much-valued tool in diverse areas of molecular genetics, as also will be discussed here.
Collapse
Affiliation(s)
- Douglas E Berg
- Division of Infectious Disease, Department of Medicine, University of California San Diego, La Jolla, CA, USA
| |
Collapse
|