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Hayashi M, Wada Y, Yamamura A, Inoue H, Yamashita N, Ichimura S, Iida Y. Evaluation of the enzymatic properties of DNA (cytosine-5)-methyltransferase M.ApeKI from archaea in the presence of metal ions. Biosci Biotechnol Biochem 2024; 88:1155-1163. [PMID: 39085041 DOI: 10.1093/bbb/zbae106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2024] [Accepted: 07/16/2024] [Indexed: 08/02/2024]
Abstract
We previously identified M.ApeKI from Aeropyum pernix K1 as a highly thermostable DNA (cytosine-5)-methyltransferase. M.ApeKI uses the type II restriction-modification system (R-M system), among the best-studied R-M systems. Although endonucleases generally utilize Mg (II) as a cofactor, several reports have shown that MTases exhibit different reactions in the presence of metal ions. This study aim was to evaluate the enzymatic properties of DNA (cytosine-5)-methyltransferase M.ApeKI from archaea in the presence of metal ions. We evaluated the influence of metal ions on the catalytic activity and DNA binding of M.ApeKI. The catalytic activity was inhibited by Cu (II), Mg (II), Mn (II), and Zn (II), each at 5 m m. DNA binding was more strongly inhibited by 5 m m Cu (II) and 10 m m Zn (II). To our knowledge, this is the first report showing that DNA binding of type II MTase is inhibited by metal ions.
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Affiliation(s)
- Mao Hayashi
- Department of Applied Chemistry and Bioscience, Graduate School of Engineering, Kanagawa Institute of Technology, Atsugi, Kanagawa, Japan
| | - Yoshinari Wada
- Department of Applied Bioscience, Faculty of Applied Bioscience, Kanagawa Institute of Technology, Atsugi, Kanagawa, Japan
| | - Akira Yamamura
- Department of Applied Chemistry and Bioscience, Graduate School of Engineering, Kanagawa Institute of Technology, Atsugi, Kanagawa, Japan
- Department of Applied Bioscience, Faculty of Applied Bioscience, Kanagawa Institute of Technology, Atsugi, Kanagawa, Japan
| | - Hideki Inoue
- Department of Applied Chemistry and Bioscience, Graduate School of Engineering, Kanagawa Institute of Technology, Atsugi, Kanagawa, Japan
- Department of Applied Bioscience, Faculty of Applied Bioscience, Kanagawa Institute of Technology, Atsugi, Kanagawa, Japan
| | - Naoya Yamashita
- Department of Applied Chemistry and Bioscience, Graduate School of Engineering, Kanagawa Institute of Technology, Atsugi, Kanagawa, Japan
- Department of Applied Bioscience, Faculty of Applied Bioscience, Kanagawa Institute of Technology, Atsugi, Kanagawa, Japan
| | - Shigetoshi Ichimura
- Department of Applied Chemistry and Bioscience, Graduate School of Engineering, Kanagawa Institute of Technology, Atsugi, Kanagawa, Japan
- Department of Applied Bioscience, Faculty of Applied Bioscience, Kanagawa Institute of Technology, Atsugi, Kanagawa, Japan
| | - Yasuhiro Iida
- Department of Applied Chemistry and Bioscience, Graduate School of Engineering, Kanagawa Institute of Technology, Atsugi, Kanagawa, Japan
- Department of Applied Bioscience, Faculty of Applied Bioscience, Kanagawa Institute of Technology, Atsugi, Kanagawa, Japan
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2
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Gomez JB, Waters CM. A Vibrio cholerae Type IV restriction system targets glucosylated 5-hydroxymethylcytosine to protect against phage infection. J Bacteriol 2024; 206:e0014324. [PMID: 39230524 PMCID: PMC11411926 DOI: 10.1128/jb.00143-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Accepted: 08/03/2024] [Indexed: 09/05/2024] Open
Abstract
A major challenge faced by Vibrio cholerae is constant predation by bacteriophage (phage) in aquatic reservoirs and during infection of human hosts. To overcome phage predation, V. cholerae has acquired and/or evolved a myriad of phage defense systems. Although several novel defense systems have been discovered, we hypothesized that more were encoded in V. cholerae given the low diversity of phages that have been isolated, which infect this species. Using a V. cholerae genomic library, we identified a Type IV restriction system consisting of two genes within a 16-kB region of the Vibrio pathogenicity island-2, which we name TgvA and TgvB (Type I-embedded gmrSD-like system of VPI-2). We show that both TgvA and TgvB are required for defense against T2, T4, and T6 by targeting glucosylated 5-hydroxymethylcytosine (5hmC). T2 or T4 phages that lose the glucose modifications are resistant to TgvAB defense but exhibit a significant evolutionary tradeoff, becoming susceptible to other Type IV restriction systems that target unglucosylated 5hmC. We also show that the Type I restriction-modification system that embeds the tgvAB genes protects against phage T3, secΦ18, secΦ27, and λ, suggesting that this region is a phage defense island. Our study uncovers a novel Type IV restriction system in V. cholerae, increasing our understanding of the evolution and ecology of V. cholerae, while highlighting the evolutionary interplay between restriction systems and phage genome modification.IMPORTANCEBacteria are constantly being predated by bacteriophage (phage). To counteract this predation, bacteria have evolved a myriad of defense systems. Some of these systems specifically digest infecting phage by recognizing unique base modifications present on the phage DNA. In this study, we discover a Type IV restriction system encoded in V. cholerae, which we name TgvAB, and demonstrate it recognizes and restricts phage that have 5-hydroxymethylcytosine glucosylated DNA. Moreover, the evolution of resistance to TgvAB render phage susceptible to other Type IV restriction systems, demonstrating a significant evolutionary tradeoff. These results enhance our understanding of the evolution of V. cholerae and more broadly how bacteria evade phage predation.
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Affiliation(s)
- Jasper B Gomez
- Department of Microbiology, Genetics, & Immunology, Michigan State University, East Lansing, Michigan, USA
| | - Christopher M Waters
- Department of Microbiology, Genetics, & Immunology, Michigan State University, East Lansing, Michigan, USA
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3
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Vizzarro G, Lemopoulos A, Adams DW, Blokesch M. Vibrio cholerae pathogenicity island 2 encodes two distinct types of restriction systems. J Bacteriol 2024; 206:e0014524. [PMID: 39133004 PMCID: PMC11411939 DOI: 10.1128/jb.00145-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Accepted: 07/15/2024] [Indexed: 08/13/2024] Open
Abstract
In response to predation by bacteriophages and invasion by other mobile genetic elements such as plasmids, bacteria have evolved specialized defense systems that are often clustered together on genomic islands. The O1 El Tor strains of Vibrio cholerae responsible for the ongoing seventh cholera pandemic (7PET) contain a characteristic set of genomic islands involved in host colonization and disease, many of which contain defense systems. Notably, Vibrio pathogenicity island 2 contains several characterized defense systems as well as a putative type I restriction-modification (T1RM) system, which, interestingly, is interrupted by two genes of unknown function. Here, we demonstrate that the T1RM system is active, methylates the host genomes of a representative set of 7PET strains, and identify a specific recognition sequence that targets non-methylated plasmids for restriction. We go on to show that the two genes embedded within the T1RM system encode a novel two-protein modification-dependent restriction system related to the GmrSD family of type IV restriction enzymes. Indeed, we show that this system has potent anti-phage activity against diverse members of the Tevenvirinae, a subfamily of bacteriophages with hypermodified genomes. Taken together, these results expand our understanding of how this highly conserved genomic island contributes to the defense of pandemic V. cholerae against foreign DNA. IMPORTANCE Defense systems are immunity systems that allow bacteria to counter the threat posed by bacteriophages and other mobile genetic elements. Although these systems are numerous and highly diverse, the most common types are restriction enzymes that can specifically recognize and degrade non-self DNA. Here, we show that the Vibrio pathogenicity island 2, present in the pathogen Vibrio cholerae, encodes two types of restriction systems that use distinct mechanisms to sense non-self DNA. The first system is a classical Type I restriction-modification system, and the second is a novel modification-dependent type IV restriction system that recognizes hypermodified cytosines. Interestingly, these systems are embedded within each other, suggesting that they are complementary to each other by targeting both modified and non-modified phages.
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Affiliation(s)
- Grazia Vizzarro
- Laboratory of Molecular Microbiology, Global Health Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Alexandre Lemopoulos
- Laboratory of Molecular Microbiology, Global Health Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - David William Adams
- Laboratory of Molecular Microbiology, Global Health Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Melanie Blokesch
- Laboratory of Molecular Microbiology, Global Health Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
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4
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Meaney JS, Panchal AK, Wilcox AJ, diCenzo GC, Karas BJ. Identifying functional multi-host shuttle plasmids to advance synthetic biology applications in Mesorhizobium and Bradyrhizobium. Can J Microbiol 2024; 70:336-347. [PMID: 38564797 DOI: 10.1139/cjm-2023-0232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Ammonia availability has a crucial role in agriculture as it ensures healthy plant growth and increased crop yields. Since diazotrophs are the only organisms capable of reducing dinitrogen to ammonia, they have great ecological importance and potential to mitigate the environmental and economic costs of synthetic fertilizer use. Rhizobia are especially valuable being that they can engage in nitrogen-fixing symbiotic relationships with legumes, and they demonstrate great diversity and plasticity in genomic and phenotypic traits. However, few rhizobial species have sufficient genetic tractability for synthetic biology applications. This study established a basic genetic toolbox with antibiotic resistance markers, multi-host shuttle plasmids and a streamlined protocol for biparental conjugation with Mesorhizobium and Bradyrhizobium species. We identified two repABC origins of replication from Sinorhizobium meliloti (pSymB) and Rhizobium etli (p42d) that were stable across all three strains of interest. Furthermore, the NZP2235 genome was sequenced and phylogenetic analysis determined its reclassification to Mesorhizobium huakuii. These tools will enable the use of plasmid-based strategies for more advanced genetic engineering projects and ultimately contribute towards the development of more sustainable agriculture practices by means of novel nitrogen-fixing organelles, elite bioinoculants, or symbiotic association with nonlegumes.
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Affiliation(s)
- Jordyn S Meaney
- Department of Biochemistry, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, ON N6A 5C1, Canada
| | - Aakanx K Panchal
- Department of Biology, Queen's University, Kingston, ON K7L 3N6, Canada
| | - Aiden J Wilcox
- Department of Biochemistry, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, ON N6A 5C1, Canada
| | - George C diCenzo
- Department of Biology, Queen's University, Kingston, ON K7L 3N6, Canada
| | - Bogumil J Karas
- Department of Biochemistry, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, ON N6A 5C1, Canada
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Yang Y, Zhou P, Tian D, Wang W, Zhou Y, Jiang X. CRISPR-Cas3 and type I restriction-modification team up against bla KPC-IncF plasmid transfer in Klebsiella pneumoniae. BMC Microbiol 2024; 24:240. [PMID: 38961341 PMCID: PMC11223367 DOI: 10.1186/s12866-024-03381-7] [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: 12/04/2023] [Accepted: 06/18/2024] [Indexed: 07/05/2024] Open
Abstract
OBJECTIVE We explored whether the Clustered regularly interspaced short palindromic repeat (CRISPR)-Cas and restriction-modification (R-M) systems are compatible and act together to resist plasmid attacks. METHODS 932 global whole-genome sequences from GenBank, and 459 K. pneumoniae isolates from six provinces of China, were collected to investigate the co-distribution of CRISPR-Cas, R-M systems, and blaKPC plasmid. Conjugation and transformation assays were applied to explore the anti-plasmid function of CRISPR and R-M systems. RESULTS We found a significant inverse correlation between the presence of CRISPR and R-M systems and blaKPC plasmids in K. pneumoniae, especially when both systems cohabited in one host. The multiple matched recognition sequences of both systems in blaKPC-IncF plasmids (97%) revealed that they were good targets for both systems. Furthermore, the results of conjugation assay demonstrated that CRISPR-Cas and R-M systems in K. pneumoniae could effectively hinder blaKPC plasmid invasion. Notably, CRISPR-Cas and R-M worked together to confer a 4-log reduction in the acquisition of blaKPC plasmid in conjugative events, exhibiting robust synergistic anti-plasmid immunity. CONCLUSIONS Our results indicate the synergistic role of CRISPR and R-M in regulating horizontal gene transfer in K. pneumoniae and rationalize the development of antimicrobial strategies that capitalize on the immunocompromised status of KPC-KP.
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Affiliation(s)
- Yang Yang
- Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, China
- Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, China
| | - Peiyao Zhou
- Department of Laboratory Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Dongxing Tian
- Department of Laboratory Medicine, Shanghai Medical College, Huashan Hospital, Fudan University, Shanghai, China
| | - Weiwen Wang
- Department of Laboratory Medicine, Shanghai Medical College, Huashan Hospital, Fudan University, Shanghai, China
| | - Ying Zhou
- Department of Clinical Laboratory Medicine, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, People's Republic of China.
| | - Xiaofei Jiang
- Department of Laboratory Medicine, Shanghai Medical College, Huashan Hospital, Fudan University, Shanghai, China.
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6
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Skutel M, Yanovskaya D, Demkina A, Shenfeld A, Musharova O, Severinov K, Isaev A. RecA-dependent or independent recombination of plasmid DNA generates a conflict with the host EcoKI immunity by launching restriction alleviation. Nucleic Acids Res 2024; 52:5195-5208. [PMID: 38567730 PMCID: PMC11109961 DOI: 10.1093/nar/gkae243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 03/17/2024] [Accepted: 03/22/2024] [Indexed: 05/23/2024] Open
Abstract
Bacterial defence systems are tightly regulated to avoid autoimmunity. In Type I restriction-modification (R-M) systems, a specific mechanism called restriction alleviation (RA) controls the activity of the restriction module. In the case of the Escherichia coli Type I R-M system EcoKI, RA proceeds through ClpXP-mediated proteolysis of restriction complexes bound to non-methylated sites that appear after replication or reparation of host DNA. Here, we show that RA is also induced in the presence of plasmids carrying EcoKI recognition sites, a phenomenon we refer to as plasmid-induced RA. Further, we show that the anti-restriction behavior of plasmid-borne non-conjugative transposons such as Tn5053, previously attributed to their ardD loci, is due to plasmid-induced RA. Plasmids carrying both EcoKI and Chi sites induce RA in RecA- and RecBCD-dependent manner. However, inactivation of both RecA and RecBCD restores RA, indicating that there exists an alternative, RecA-independent, homologous recombination pathway that is blocked in the presence of RecBCD. Indeed, plasmid-induced RA in a RecBCD-deficient background does not depend on the presence of Chi sites. We propose that processing of random dsDNA breaks in plasmid DNA via homologous recombination generates non-methylated EcoKI sites, which attract EcoKI restriction complexes channeling them for ClpXP-mediated proteolysis.
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Affiliation(s)
- Mikhail Skutel
- Skolkovo Institute of Science and Technology, Moscow, Russia
| | - Daria Yanovskaya
- Skolkovo Institute of Science and Technology, Moscow, Russia
- Moscow Institute of Physics and Technology, Moscow, Russia
| | - Alina Demkina
- Skolkovo Institute of Science and Technology, Moscow, Russia
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Moscow, Russia
| | | | - Olga Musharova
- Skolkovo Institute of Science and Technology, Moscow, Russia
- Institute of Molecular Genetics, National Research Center Kurchatov Institute, Moscow, Russia
| | - Konstantin Severinov
- Waksman Institute of Microbiology, Piscataway, USA
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
| | - Artem Isaev
- Skolkovo Institute of Science and Technology, Moscow, Russia
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7
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Gomez JB, Waters CM. A Vibrio cholerae Type IV restriction system targets glucosylated 5-hydroxyl methyl cytosine to protect against phage infection. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.05.588314. [PMID: 38617239 PMCID: PMC11014532 DOI: 10.1101/2024.04.05.588314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/16/2024]
Abstract
A major challenge faced by Vibrio cholerae is constant predation by bacteriophage (phage) in aquatic reservoirs and during infection of human hosts. To overcome phage predation, V. cholerae has evolved a myriad of phage defense systems. Although several novel defense systems have been discovered, we hypothesized more were encoded in V. cholerae given the relative paucity of phage that have been isolated which infect this species. Using a V. cholerae genomic library, we identified a Type IV restriction system consisting of two genes within a 16kB region of the Vibrio pathogenicity island-2 that we name TgvA and TgvB (Type I-embedded gmrSD-like system of VPI-2). We show that both TgvA and TgvB are required for defense against T2, T4, and T6 by targeting glucosylated 5-hydroxymethylcytosine (5hmC). T2 or T4 phages that lose the glucose modification are resistant to TgvAB defense but exhibit a significant evolutionary tradeoff becoming susceptible to other Type IV restriction systems that target unglucosylated 5hmC. We show that additional phage defense genes are encoded in VPI-2 that protect against other phage like T3, secΦ18, secΦ27 and λ. Our study uncovers a novel Type IV restriction system in V. cholerae, increasing our understanding of the evolution and ecology of V. cholerae while highlighting the evolutionary interplay between restriction systems and phage genome modification.
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Affiliation(s)
- Jasper B Gomez
- Department of Microbiology, Genetics, and Immunology, Michigan State University, East Lansing, Michigan, USA
| | - Christopher M Waters
- Department of Microbiology, Genetics, and Immunology, Michigan State University, East Lansing, Michigan, USA
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8
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Orel N, Fadeev E, Herndl GJ, Turk V, Tinta T. Recovering high-quality bacterial genomes from cross-contaminated cultures: a case study of marine Vibrio campbellii. BMC Genomics 2024; 25:146. [PMID: 38321410 PMCID: PMC10845552 DOI: 10.1186/s12864-024-10062-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 01/29/2024] [Indexed: 02/08/2024] Open
Abstract
BACKGROUND Environmental monitoring of bacterial pathogens is critical for disease control in coastal marine ecosystems to maintain animal welfare and ecosystem function and to prevent significant economic losses. This requires accurate taxonomic identification of environmental bacterial pathogens, which often cannot be achieved by commonly used genetic markers (e.g., 16S rRNA gene), and an understanding of their pathogenic potential based on the information encoded in their genomes. The decreasing costs of whole genome sequencing (WGS), combined with newly developed bioinformatics tools, now make it possible to unravel the full potential of environmental pathogens, beyond traditional microbiological approaches. However, obtaining a high-quality bacterial genome, requires initial cultivation in an axenic culture, which is a bottleneck in environmental microbiology due to cross-contamination in the laboratory or isolation of non-axenic strains. RESULTS We applied WGS to determine the pathogenic potential of two Vibrio isolates from coastal seawater. During the analysis, we identified cross-contamination of one of the isolates and decided to use this dataset to evaluate the possibility of bioinformatic contaminant removal and recovery of bacterial genomes from a contaminated culture. Despite the contamination, using an appropriate bioinformatics workflow, we were able to obtain high quality and highly identical genomes (Average Nucleotide Identity value 99.98%) of one of the Vibrio isolates from both the axenic and the contaminated culture. Using the assembled genome, we were able to determine that this isolate belongs to a sub-lineage of Vibrio campbellii associated with several diseases in marine organisms. We also found that the genome of the isolate contains a novel Vibrio plasmid associated with bacterial defense mechanisms and horizontal gene transfer, which may offer a competitive advantage to this putative pathogen. CONCLUSIONS Our study shows that, using state-of-the-art bioinformatics tools and a sufficient sequencing effort, it is possible to obtain high quality genomes of the bacteria of interest and perform in-depth genomic analyses even in the case of a contaminated culture. With the new isolate and its complete genome, we are providing new insights into the genomic characteristics and functional potential of this sub-lineage of V. campbellii. The approach described here also highlights the possibility of recovering complete bacterial genomes in the case of non-axenic cultures or obligatory co-cultures.
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Affiliation(s)
- Neža Orel
- Marine Biology Station Piran, National Institute of Biology, Piran, Slovenia.
| | - Eduard Fadeev
- Department of Functional and Evolutionary Ecology, Bio-Oceanography and Marine Biology Unit, University of Vienna, Vienna, Austria
| | - Gerhard J Herndl
- Department of Functional and Evolutionary Ecology, Bio-Oceanography and Marine Biology Unit, University of Vienna, Vienna, Austria
- NIOZ, Department of Marine Microbiology and Biogeochemistry, Royal Netherlands Institute for Sea Research, Den Burg, The Netherlands
| | - Valentina Turk
- Marine Biology Station Piran, National Institute of Biology, Piran, Slovenia
| | - Tinkara Tinta
- Marine Biology Station Piran, National Institute of Biology, Piran, Slovenia.
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Cheung GYC, Lee JH, Liu R, Lawhon SD, Yang C, Otto M. Methicillin Resistance Elements in the Canine Pathogen Staphylococcus pseudintermedius and Their Association with the Peptide Toxin PSM-mec. Antibiotics (Basel) 2024; 13:130. [PMID: 38391516 PMCID: PMC10886032 DOI: 10.3390/antibiotics13020130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 01/23/2024] [Accepted: 01/25/2024] [Indexed: 02/24/2024] Open
Abstract
Staphylococcus pseudintermedius is a frequent cause of infections in dogs. Infectious isolates of this coagulase-positive staphylococcal species are often methicillin- and multidrug-resistant, which complicates therapy. In staphylococci, methicillin resistance is encoded by determinants found on mobile genetic elements called Staphylococcal Chromosome Cassette mec (SCCmec), which, in addition to methicillin resistance factors, sometimes encode additional genes, such as further resistance factors and, rarely, virulence determinants. In this study, we analyzed SCCmec in a collection of infectious methicillin-resistant S. pseudintermedius (MRSP) isolates from predominant lineages in the United States. We found that several lineages characteristically have specific types of SCCmec elements and Agr types and harbor additional factors in their SCCmec elements that may promote virulence or affect DNA uptake. All isolates had SCCmec-encoded restriction-modification (R-M) systems of types I or II, and sequence types (STs) ST84 and ST64 had one type II and one type I R-M system, although the latter lacked a complete methylation enzyme gene. ST68 isolates also had an SCCmec-encoded CRISPR system. ST71 isolates had a psm-mec gene, which, in all but apparently Agr-dysfunctional isolates, produced a PSM-mec peptide toxin, albeit at relatively small amounts. This study gives detailed insight into the composition of SCCmec elements in infectious isolates of S. pseudintermedius and lays the genetic foundation for further efforts directed at elucidating the contribution of identified accessory SCCmec factors in impacting SCCmec-encoded and thus methicillin resistance-associated virulence and resistance to DNA uptake in this leading canine pathogen.
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Affiliation(s)
- Gordon Y C Cheung
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases (NIAID), US National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Ji Hyun Lee
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases (NIAID), US National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Ryan Liu
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases (NIAID), US National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Sara D Lawhon
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843, USA
| | - Ching Yang
- Department of Veterinary Biomedical Sciences, College of Veterinary Medicine, Long Island University, Brookville, NY 11548, USA
| | - Michael Otto
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases (NIAID), US National Institutes of Health (NIH), Bethesda, MD 20892, USA
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10
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Kottenhahn P, Philipps G, Bunk B, Spröer C, Jennewein S. The Restriction-Modification Systems of Clostridium carboxidivorans P7. Microorganisms 2023; 11:2962. [PMID: 38138106 PMCID: PMC10745947 DOI: 10.3390/microorganisms11122962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 11/30/2023] [Accepted: 12/01/2023] [Indexed: 12/24/2023] Open
Abstract
Clostridium carboxidivorans P7 (DSM 15243) is a bacterium that converts syngas (a mixture of CO, H2, and CO2) into hexanol. An optimized and scaled-up industrial process could therefore provide a renewable source of fuels and chemicals while consuming industry waste gases. However, the genetic engineering of this bacterium is hindered by its multiple restriction-modification (RM) systems: the genome of C. carboxidivorans encodes at least ten restriction enzymes and eight methyltransferases (MTases). To gain insight into the complex RM systems of C. carboxidivorans, we analyzed genomic methylation patterns using single-molecule real-time (SMRT) sequencing and bisulfite sequencing. We identified six methylated sequence motifs. To match the methylation sites to the predicted MTases of C. carboxidivorans, we expressed them individually in Escherichia coli for functional characterization. Recognition motifs were identified for all three Type I MTases (CAYNNNNNCTGC/GCAGNNNNNRTG, CCANNNNNNNNTCG/CGANNNNNNNNTGG and GCANNNNNNNTNNCG/CGNNANNNNNNNTGC), two Type II MTases (GATAAT and CRAAAAR), and a single Type III MTase (GAAAT). However, no methylated recognition motif was found for one of the three Type II enzymes. One recognition motif that was methylated in C. carboxidivorans but not in E. coli (AGAAGC) was matched to the remaining Type III MTase through a process of elimination. Understanding these enzymes and the corresponding recognition sites will facilitate the development of genetic tools for C. carboxidivorans that can accelerate the industrial exploitation of this strain.
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Affiliation(s)
- Patrick Kottenhahn
- Department of Industrial Biotechnology, Fraunhofer Institute for Molecular Biology and Applied Ecology IME, 52074 Aachen, Germany
- Department of Biology, RWTH Aachen University, 52074 Aachen, Germany
| | - Gabriele Philipps
- Department of Industrial Biotechnology, Fraunhofer Institute for Molecular Biology and Applied Ecology IME, 52074 Aachen, Germany
| | - Boyke Bunk
- Department Bioinformatics and Databases, Leibniz Institute DSMZ-German Culture Collection for Microorganisms and Cell Cultures, 38124 Braunschweig, Germany
| | - Cathrin Spröer
- Department Bioinformatics and Databases, Leibniz Institute DSMZ-German Culture Collection for Microorganisms and Cell Cultures, 38124 Braunschweig, Germany
| | - Stefan Jennewein
- Department of Industrial Biotechnology, Fraunhofer Institute for Molecular Biology and Applied Ecology IME, 52074 Aachen, Germany
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11
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Skutel M, Andriianov A, Zavialova M, Kirsanova M, Shodunke O, Zorin E, Golovshchinskii A, Severinov K, Isaev A. T5-like phage BF23 evades host-mediated DNA restriction and methylation. MICROLIFE 2023; 4:uqad044. [PMID: 38025991 PMCID: PMC10644984 DOI: 10.1093/femsml/uqad044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 10/15/2023] [Accepted: 10/25/2023] [Indexed: 12/01/2023]
Abstract
Bacteriophage BF23 is a close relative of phage T5, a prototypical Tequintavirus that infects Escherichia coli. BF23 was isolated in the middle of the XXth century and was extensively studied as a model object. Like T5, BF23 carries long ∼9.7 kb terminal repeats, injects its genome into infected cell in a two-stage process, and carries multiple specific nicks in its double-stranded genomic DNA. The two phages rely on different host secondary receptors-FhuA (T5) and BtuB (BF23). Only short fragments of the BF23 genome, including the region encoding receptor interacting proteins, have been determined. Here, we report the full genomic sequence of BF23 and describe the protein content of its virion. T5-like phages represent a unique group that resist restriction by most nuclease-based host immunity systems. We show that BF23, like other Tequintavirus phages, resist Types I/II/III restriction-modification host immunity systems if their recognition sites are located outside the terminal repeats. We also demonstrate that the BF23 avoids host-mediated methylation. We propose that inhibition of methylation is a common feature of Tequintavirus and Epseptimavirus genera phages, that is not, however, associated with their antirestriction activity.
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Affiliation(s)
- Mikhail Skutel
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30/1, 143028, Moscow, Russia
| | - Aleksandr Andriianov
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30/1, 143028, Moscow, Russia
| | - Maria Zavialova
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30/1, 143028, Moscow, Russia
- Institute of Biomedical Chemistry (IBMC), Pogodinskaya 10/8, 119435, Moscow, Russia
| | - Maria Kirsanova
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30/1, 143028, Moscow, Russia
| | - Oluwasefunmi Shodunke
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30/1, 143028, Moscow, Russia
- Moscow Institute of Physics and Technology, Institutskiy Pereulok 9, 141701, Dolgoprudny, Russia
| | - Evgenii Zorin
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30/1, 143028, Moscow, Russia
| | | | - Konstantin Severinov
- Waksman Institute of Microbiology, 190 Frelinghuysen Rd, NJ 08854, Piscataway, United States
| | - Artem Isaev
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30/1, 143028, Moscow, Russia
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12
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Sun C, Chen J, Jin M, Zhao X, Li Y, Dong Y, Gao N, Liu Z, Bork P, Zhao X, Chen W. Long-Read Sequencing Reveals Extensive DNA Methylations in Human Gut Phagenome Contributed by Prevalently Phage-Encoded Methyltransferases. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2302159. [PMID: 37382405 PMCID: PMC10477858 DOI: 10.1002/advs.202302159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Indexed: 06/30/2023]
Abstract
DNA methylation plays a crucial role in the survival of bacteriophages (phages), yet the understanding of their genome methylation remains limited. In this study, DNA methylation patterns are analyzed in 8848 metagenome-assembled high-quality phages from 104 fecal samples using single-molecule real-time sequencing. The results demonstrate that 97.60% of gut phages exhibit methylation, with certain factors correlating with methylation densities. Phages with higher methylation densities appear to have potential viability advantages. Strikingly, more than one-third of the phages possess their own DNA methyltransferases (MTases). Increased MTase copies are associated with higher genome methylation densities, specific methylation motifs, and elevated prevalence of certain phage groups. Notably, the majority of these MTases share close homology with those encoded by gut bacteria, suggesting their exchange during phage-bacterium interactions. Furthermore, these MTases can be employed to accurately predict phage-host relationships. Overall, the findings indicate the widespread utilization of DNA methylation by gut DNA phages as an evasion mechanism against host defense systems, with a substantial contribution from phage-encoded MTases.
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Affiliation(s)
- Chuqing Sun
- Key Laboratory of Molecular Biophysics of the Ministry of Education, Hubei Key Laboratory of Bioinformatics and Molecular Imaging, Center for Artificial Intelligence Biology, Department of Bioinformatics and Systems Biology, College of Life Science and TechnologyHuazhong University of Science and TechnologyWuhanHubei430074P. R. China
| | - Jingchao Chen
- Key Laboratory of Molecular Biophysics of the Ministry of Education, Hubei Key Laboratory of Bioinformatics and Molecular Imaging, Center for Artificial Intelligence Biology, Department of Bioinformatics and Systems Biology, College of Life Science and TechnologyHuazhong University of Science and TechnologyWuhanHubei430074P. R. China
| | - Menglu Jin
- Key Laboratory of Molecular Biophysics of the Ministry of Education, Hubei Key Laboratory of Bioinformatics and Molecular Imaging, Center for Artificial Intelligence Biology, Department of Bioinformatics and Systems Biology, College of Life Science and TechnologyHuazhong University of Science and TechnologyWuhanHubei430074P. R. China
| | - Xueyang Zhao
- College of Life ScienceHenan Normal UniversityXinxiangHenan453007P. R. China
| | - Yun Li
- Key Laboratory of Molecular Biophysics of the Ministry of Education, Hubei Key Laboratory of Bioinformatics and Molecular Imaging, Center for Artificial Intelligence Biology, Department of Bioinformatics and Systems Biology, College of Life Science and TechnologyHuazhong University of Science and TechnologyWuhanHubei430074P. R. China
| | - Yanqi Dong
- Institute of Science and Technology for Brain‐Inspired IntelligenceFudan UniversityShanghai200433P. R. China
| | - Na Gao
- Key Laboratory of Molecular Biophysics of the Ministry of Education, Hubei Key Laboratory of Bioinformatics and Molecular Imaging, Center for Artificial Intelligence Biology, Department of Bioinformatics and Systems Biology, College of Life Science and TechnologyHuazhong University of Science and TechnologyWuhanHubei430074P. R. China
- Department of Laboratory Medicine, Zhongnan Hospital of Wuhan UniversityWuhan UniversityWuhan430071P. R. China
| | - Zhi Liu
- Department of Biotechnology, College of Life Science and TechnologyHuazhong University of Science and TechnologyWuhan430074P. R. China
| | - Peer Bork
- European Molecular Biology LaboratoryStructural and Computational Biology Unit69117HeidelbergGermany
- Max Delbrück Centre for Molecular Medicine13125BerlinGermany
- Yonsei Frontier Lab (YFL)Yonsei UniversitySeoul03722South Korea
- Department of Bioinformatics, BiocenterUniversity of Würzburg97070WürzburgGermany
| | - Xing‐Ming Zhao
- Institute of Science and Technology for Brain‐Inspired IntelligenceFudan UniversityShanghai200433P. R. China
- MOE Key Laboratory of Computational Neuroscience and Brain‐Inspired Intelligence and MOE Frontiers Center for Brain ScienceFudan UniversityShanghai200433P. R. China
- State Key Laboratory of Medical Neurobiology, Institute of Brain ScienceFudan UniversityShanghai200433P. R. China
- Department of Neurology, Zhongshan HospitalFudan UniversityShanghai200032P. R. China
- International Human Phenome Institutes (Shanghai)Shanghai200433P. R. China
| | - Wei‐Hua Chen
- Key Laboratory of Molecular Biophysics of the Ministry of Education, Hubei Key Laboratory of Bioinformatics and Molecular Imaging, Center for Artificial Intelligence Biology, Department of Bioinformatics and Systems Biology, College of Life Science and TechnologyHuazhong University of Science and TechnologyWuhanHubei430074P. R. China
- College of Life ScienceHenan Normal UniversityXinxiangHenan453007P. R. China
- Institution of Medical Artificial IntelligenceBinzhou Medical UniversityYantai264003P. R. China
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13
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Ma J, Zhao H, Mo S, Li J, Ma X, Tang Y, Li H, Liu Z. Acquisition of Type I methyltransferase via horizontal gene transfer increases the drug resistance of Aeromonas veronii. Microb Genom 2023; 9:001107. [PMID: 37754275 PMCID: PMC10569733 DOI: 10.1099/mgen.0.001107] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Accepted: 09/14/2023] [Indexed: 09/28/2023] Open
Abstract
Aeromonas veronii is an opportunistic pathogen that affects both fish and mammals, including humans, leading to bacteraemia, sepsis, meningitis and even death. The increasing virulence and drug resistance of A. veronii are of significant concern and pose a severe risk to public safety. The Type I restriction-modification (RM) system, which functions as a bacterial defence mechanism, can influence gene expression through DNA methylation. However, little research has been conducted to explore its origin, evolutionary path, and relationship to virulence and drug resistance in A. veronii. In this study, we analysed the pan-genome of 233 A. veronii strains, and the results indicated that it was 'open', meaning that A. veronii has acquired additional genes from other species. This suggested that A. veronii had the potential to adapt and evolve rapidly, which might have contributed to its drug resistance. One Type I methyltransferase (MTase) and two complete Type I RM systems were identified, namely AveC4I, AveC4II and AveC4III in A. veronii strain C4, respectively. Notably, AveC4I was exclusive to A. veronii C4. Phylogenetic analysis revealed that AveC4I was derived from horizontal gene transfer from Thiocystis violascens and exchanged genes with the human pathogen Comamonas kerstersii. Single molecule real-time sequencing was applied to identify the motif methylated by AveC4I, which was unique and not recognized by any reported MTases in the REBASE database. We also annotated the functions and pathways of the genes containing the motif, revealing that AveC4I may control drug resistance in A. veronii C4. Our findings provide new insight on the mechanisms underlying drug resistance in pathogenic bacteria. By identifying the specific genes and pathways affected by AveC4I, this study may aid in the development of new therapeutic approaches to combat A. veronii infections.
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Affiliation(s)
- Jiayue Ma
- School of Life Sciences, Hainan University, Haikou, PR China
| | - Honghao Zhao
- School of Life Sciences, Hainan University, Haikou, PR China
| | - Shuangyi Mo
- School of Life Sciences, Hainan University, Haikou, PR China
| | - Juanjuan Li
- School of Life Sciences, Hainan University, Haikou, PR China
| | - Xiang Ma
- School of Life Sciences, Hainan University, Haikou, PR China
| | - Yanqiong Tang
- School of Life Sciences, Hainan University, Haikou, PR China
| | - Hong Li
- School of Life Sciences, Hainan University, Haikou, PR China
| | - Zhu Liu
- School of Life Sciences, Hainan University, Haikou, PR China
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14
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Ailloud F, Gottschall W, Suerbaum S. Methylome evolution suggests lineage-dependent selection in the gastric pathogen Helicobacter pylori. Commun Biol 2023; 6:839. [PMID: 37573385 PMCID: PMC10423294 DOI: 10.1038/s42003-023-05218-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 08/04/2023] [Indexed: 08/14/2023] Open
Abstract
The bacterial pathogen Helicobacter pylori, the leading cause of gastric cancer, is genetically highly diverse and harbours a large and variable portfolio of restriction-modification systems. Our understanding of the evolution and function of DNA methylation in bacteria is limited. Here, we performed a comprehensive analysis of the methylome diversity in H. pylori, using a dataset of 541 genomes that included all known phylogeographic populations. The frequency of 96 methyltransferases and the abundance of their cognate recognition sequences were strongly influenced by phylogeographic structure and were inter-correlated, positively or negatively, for 20% of type II methyltransferases. Low density motifs were more likely to be affected by natural selection, as reflected by higher genomic instability and compositional bias. Importantly, direct correlation implied that methylation patterns can be actively enriched by positive selection and suggests that specific sites have important functions in methylation-dependent phenotypes. Finally, we identified lineage-specific selective pressures modulating the contraction and expansion of the motif ACGT, revealing that the genetic load of methylation could be dependent on local ecological factors. Taken together, natural selection may shape both the abundance and distribution of methyltransferases and their specific recognition sequences, likely permitting a fine-tuning of genome-encoded functions not achievable by genetic variation alone.
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Affiliation(s)
- Florent Ailloud
- Medical Microbiology and Hospital Epidemiology, Max von Pettenkofer Institute, Faculty of Medicine, LMU Munich, Munich, Germany.
- German Center for Infection Research (DZIF), Partner Site Munich, Munich, Germany.
| | - Wilhelm Gottschall
- Medical Microbiology and Hospital Epidemiology, Max von Pettenkofer Institute, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Sebastian Suerbaum
- Medical Microbiology and Hospital Epidemiology, Max von Pettenkofer Institute, Faculty of Medicine, LMU Munich, Munich, Germany.
- German Center for Infection Research (DZIF), Partner Site Munich, Munich, Germany.
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15
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Kudryavtseva AA, Cséfalvay E, Gnuchikh EY, Yanovskaya DD, Skutel MA, Isaev AB, Bazhenov SV, Utkina AA, Manukhov IV. Broadness and specificity: ArdB, ArdA, and Ocr against various restriction-modification systems. Front Microbiol 2023; 14:1133144. [PMID: 37138625 PMCID: PMC10149784 DOI: 10.3389/fmicb.2023.1133144] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Accepted: 03/10/2023] [Indexed: 05/05/2023] Open
Abstract
ArdB, ArdA, and Ocr proteins inhibit the endonuclease activity of the type I restriction-modification enzymes (RMI). In this study, we evaluated the ability of ArdB, ArdA, and Ocr to inhibit different subtypes of Escherichia coli RMI systems (IA, IB, and IC) as well as two Bacillus licheniformis RMI systems. Furthermore we explored, the antirestriction activity of ArdA, ArdB, and Ocr against a type III restriction-modification system (RMIII) EcoPI and BREX. We found that DNA-mimic proteins, ArdA and Ocr exhibit different inhibition activity, depending on which RM system tested. This effect might be linked to the DNA mimicry nature of these proteins. In theory, DNA-mimic might competitively inhibit any DNA-binding proteins; however, the efficiency of inhibition depend on the ability to imitate the recognition site in DNA or its preferred conformation. In contrast, ArdB protein with an undescribed mechanism of action, demonstrated greater versatility against various RMI systems and provided similar antirestriction efficiency regardless of the recognition site. However, ArdB protein could not affect restriction systems that are radically different from the RMI such as BREX or RMIII. Thus, we assume that the structure of DNA-mimic proteins allows for selective inhibition of any DNA-binding proteins depending on the recognition site. In contrast, ArdB-like proteins inhibit RMI systems independently of the DNA recognition site.
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Affiliation(s)
- Anna A. Kudryavtseva
- Laboratory for Molecular Genetics, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Eva Cséfalvay
- Laboratory of Structural Biology and Bioinformatics, Institute of Microbiology, Academy of Sciences of the Czech Republic, Nové Hrady, Czechia
| | - Evgeniy Yu Gnuchikh
- Kurchatov Genomic Center, National Research Center Kurchatov Institute, Moscow, Russia
| | - Darya D. Yanovskaya
- Center of Cellular and Molecular Biology, Skolkovo Institute of Science and Technology, Moscow, Russia
| | - Mikhail A. Skutel
- Center of Cellular and Molecular Biology, Skolkovo Institute of Science and Technology, Moscow, Russia
| | - Artem B. Isaev
- Center of Cellular and Molecular Biology, Skolkovo Institute of Science and Technology, Moscow, Russia
| | - Sergey V. Bazhenov
- Laboratory for Molecular Genetics, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
- Laboratory for Microbiology, BIOTECH University, Moscow, Russia
- Faculty of Physics, HSE University, Moscow, Russia
| | - Anna A. Utkina
- Laboratory for Molecular Genetics, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Ilya V. Manukhov
- Laboratory for Molecular Genetics, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
- Laboratory for Microbiology, BIOTECH University, Moscow, Russia
- Faculty of Physics, HSE University, Moscow, Russia
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16
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Al-Trad EI, Che Hamzah AM, Puah SM, Chua KH, Hanifah MZ, Ayub Q, Palittapongarnpim P, Kwong SM, Chew CH, Yeo CC. Complete Genome Sequence and Analysis of a ST573 Multidrug-Resistant Methicillin-Resistant Staphylococcus aureus SauR3 Clinical Isolate from Terengganu, Malaysia. Pathogens 2023; 12:pathogens12030502. [PMID: 36986424 PMCID: PMC10053073 DOI: 10.3390/pathogens12030502] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Revised: 03/17/2023] [Accepted: 03/21/2023] [Indexed: 03/30/2023] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is a World Health Organization-listed priority pathogen. Scarce genomic data are available for MRSA isolates from Malaysia. Here, we present the complete genome sequence of a multidrug-resistant MRSA strain SauR3, isolated from the blood of a 6-year-old patient hospitalized in Terengganu, Malaysia, in 2016. S. aureus SauR3 was resistant to five antimicrobial classes comprising nine antibiotics. The genome was sequenced on the Illumina and Oxford Nanopore platforms and hybrid assembly was performed to obtain its complete genome sequence. The SauR3 genome consists of a circular chromosome of 2,800,017 bp and three plasmids designated pSauR3-1 (42,928 bp), pSauR3-2 (3011 bp), and pSauR3-3 (2473 bp). SauR3 belongs to sequence type 573 (ST573), a rarely reported sequence type of the staphylococcal clonal complex 1 (CC1) lineage, and harbors a variant of the staphylococcal cassette chromosome mec (SCCmec) type V (5C2&5) element which also contains the aac(6')-aph(2″) aminoglycoside-resistance genes. pSauR3-1 harbors several antibiotic resistance genes in a 14,095 bp genomic island (GI), previously reported in the chromosome of other staphylococci. pSauR3-2 is cryptic, whereas pSauR3-3 encodes the ermC gene that mediates inducible resistance to macrolide-lincosamide-streptogramin B (iMLSB). The SauR3 genome can potentially be used as a reference genome for other ST573 isolates.
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Affiliation(s)
- Esra'a I Al-Trad
- Centre for Research in Infectious Diseases and Biotechnology (CeRIDB), Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Terengganu 20400, Malaysia
| | | | - Suat Moi Puah
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| | - Muhamad Zarul Hanifah
- Monash University Malaysia Genomics Facility, School of Science, Monash University, Bandar Sunway 47500, Malaysia
| | - Qasim Ayub
- Monash University Malaysia Genomics Facility, School of Science, Monash University, Bandar Sunway 47500, Malaysia
| | - Prasit Palittapongarnpim
- Pornchai Matangkasombut Center for Microbial Genomics (CENMIG), Mahidol University, Bangkok 10400, Thailand
| | - Stephen M Kwong
- Infectious Diseases & Microbiology, School of Medicine, Western Sydney University, Campbelltown 2560, Australia
| | - Ching Hoong Chew
- Faculty of Health Sciences, Universiti Sultan Zainal Abidin, Kuala Nerus 21300, Malaysia
| | - Chew Chieng Yeo
- Centre for Research in Infectious Diseases and Biotechnology (CeRIDB), Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Terengganu 20400, Malaysia
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17
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Natural Recombination among Type I Restriction-Modification Systems Creates Diverse Genomic Methylation Patterns among Xylella fastidiosa Strains. Appl Environ Microbiol 2023; 89:e0187322. [PMID: 36598481 PMCID: PMC9888226 DOI: 10.1128/aem.01873-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Xylella fastidiosa is an important bacterial plant pathogen causing high-consequence diseases in agricultural crops around the world. Although as a species X. fastidiosa can infect many host plants, there is significant variability between strains regarding virulence on specific host plant species and other traits. Natural competence and horizontal gene transfer are believed to occur frequently in X. fastidiosa and likely influence the evolution of this pathogen. However, some X. fastidiosa strains are difficult to manipulate genetically using standard transformation techniques. Several type I restriction-modification (R-M) systems are encoded in the X. fastidiosa genome, which may influence horizontal gene transfer and recombination. Type I R-M systems themselves may undergo recombination, exchanging target recognition domains (TRDs) between specificity subunits (hsdS) to generate novel alleles with new target specificities. In this study, several conserved type I R-M systems were compared across 129 X. fastidiosa genome assemblies representing all known subspecies and 32 sequence types. Forty-four unique TRDs were identified among 50 hsdS alleles, which are arrayed in 31 allele profiles that are generally conserved within a monophyletic cluster of strains. Inactivating mutations were identified in type I R-M systems of specific strains, showing heterogeneity in the complements of functional type I R-M systems across X. fastidiosa. Genomic DNA methylation patterns were characterized in 20 X. fastidiosa strains and associated with type I R-M system allele profiles. Overall, these data suggest hsdS genes recombine among Xylella strains and/or unknown donors, and the resulting TRD reassortment establishes differential epigenetic modifications across Xylella lineages. IMPORTANCE Economic impacts on agricultural production due to X. fastidiosa have been severe in the Americas, Europe, and parts of Asia. Despite a long history of research on this pathogen, certain fundamental questions regarding the biology, pathogenicity, and evolution of X. fastidiosa have still not been answered. Wide-scale whole-genome sequencing has begun to provide more insight into X. fastidiosa genetic diversity and horizontal gene transfer, but the mechanics of genomic recombination in natural settings and the extent to which this directly influences bacterial phenotypes such as plant host range are not well understood. Genome methylation is an important factor in horizontal gene transfer and bacterial recombination that has not been comprehensively studied in X. fastidiosa. This study characterizes methylation associated with type I restriction-modification systems across a wide range of X. fastidiosa strains and lays the groundwork for a better understanding of X. fastidiosa biology and evolution through epigenetics.
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18
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Gao Q, Lu S, Wang Y, He L, Wang M, Jia R, Chen S, Zhu D, Liu M, Zhao X, Yang Q, Wu Y, Zhang S, Huang J, Mao S, Ou X, Sun D, Tian B, Cheng A. Bacterial DNA methyltransferase: A key to the epigenetic world with lessons learned from proteobacteria. Front Microbiol 2023; 14:1129437. [PMID: 37032876 PMCID: PMC10073500 DOI: 10.3389/fmicb.2023.1129437] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 02/27/2023] [Indexed: 04/11/2023] Open
Abstract
Epigenetics modulates expression levels of various important genes in both prokaryotes and eukaryotes. These epigenetic traits are heritable without any change in genetic DNA sequences. DNA methylation is a universal mechanism of epigenetic regulation in all kingdoms of life. In bacteria, DNA methylation is the main form of epigenetic regulation and plays important roles in affecting clinically relevant phenotypes, such as virulence, host colonization, sporulation, biofilm formation et al. In this review, we survey bacterial epigenomic studies and focus on the recent developments in the structure, function, and mechanism of several highly conserved bacterial DNA methylases. These methyltransferases are relatively common in bacteria and participate in the regulation of gene expression and chromosomal DNA replication and repair control. Recent advances in sequencing techniques capable of detecting methylation signals have enabled the characterization of genome-wide epigenetic regulation. With their involvement in critical cellular processes, these highly conserved DNA methyltransferases may emerge as promising targets for developing novel epigenetic inhibitors for biomedical applications.
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Affiliation(s)
- Qun Gao
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
| | - Shuwei Lu
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Yuwei Wang
- Key Laboratory of Livestock and Poultry Provenance Disease Research in Mianyang, Sichuan, China
| | - Longgui He
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Mingshu Wang
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Renyong Jia
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Shun Chen
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Dekang Zhu
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Mafeng Liu
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Xinxin Zhao
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Qiao Yang
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Ying Wu
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Shaqiu Zhang
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Juan Huang
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Sai Mao
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Xumin Ou
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Di Sun
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Bin Tian
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Anchun Cheng
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
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19
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Schiffer CJ, Grätz C, Pfaffl MW, Vogel RF, Ehrmann MA. Characterization of the Staphylococcus xylosus methylome reveals a new variant of type I restriction modification system in staphylococci. Front Microbiol 2023; 14:946189. [PMID: 36970683 PMCID: PMC10030836 DOI: 10.3389/fmicb.2023.946189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 02/13/2023] [Indexed: 03/29/2023] Open
Abstract
Restriction modification (RM) systems are known to provide a strong barrier to the exchange of DNA between and within bacterial species. Likewise, DNA methylation is known to have an important function in bacterial epigenetics regulating essential pathways such as DNA replication and the phase variable expression of prokaryotic phenotypes. To date, research on staphylococcal DNA methylation focused mainly on the two species Staphylococcus aureus and S. epidermidis. Less is known about other members of the genus such as S. xylosus, a coagulase-negative commensal of mammalian skin. The species is commonly used as starter organism in food fermentations but is also increasingly considered to have an as yet elusive function in bovine mastitis infections. We analyzed the methylomes of 14 S. xylosus strains using single-molecular, real-time (SMRT) sequencing. Subsequent in silico sequence analysis allowed identification of the RM systems and assignment of the respective enzymes to the discovered modification patterns. Hereby the presence of type I, II, III and IV RM systems in varying numbers and combinations among the different strains was revealed, clearly distinguishing the species from what is known for other members of the genus so far. In addition, the study characterizes a newly discovered type I RM system, encoded by S. xylosus but also by a variety of other staphylococcal species, with a hitherto unknown gene arrangement that involves two specificity units instead of one (hsdRSMS). Expression of different versions of the operon in E. coli showed proper base modification only when genes encoding both hsdS subunits were present. This study provides new insights into the general understanding of the versatility and function of RM systems as well as the distribution and variations in the genus Staphylococcus.
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Affiliation(s)
- Carolin J. Schiffer
- Chair of Technical Microbiology, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
- *Correspondence: Carolin J. Schiffer,
| | - Christian Grätz
- Chair of Animal Physiology and Immunology, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Michael W. Pfaffl
- Chair of Animal Physiology and Immunology, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Rudi F. Vogel
- Chair of Technical Microbiology, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Matthias A. Ehrmann
- Chair of Technical Microbiology, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
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20
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An Emerging Lineage of Uropathogenic Extended Spectrum β-Lactamase Escherichia coli ST127. Microbiol Spectr 2022; 10:e0251122. [PMID: 36416548 PMCID: PMC9769692 DOI: 10.1128/spectrum.02511-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Uropathogenic Escherichia coli (UPEC) is one of the most common causes of urinary tract infections. Here, we report for the first time the whole-genome sequencing (WGS) and analysis of four extended-spectrum β-lactamase (ESBL), UPEC sequence type (ST) 127 isolates that were recovered from patients in five hospitals in Armenia from January to August of 2019. A phylogenetic comparison revealed that our isolates were closely related to each other by their core and accessory genomes, despite having been isolated from different regions and hospitals in Armenia. We identified unique genes in our isolates and in a closely related isolate recovered in France. The unique genes (hemolysin E virulence gene, lactate utilization operon lutABC, and endonuclease restriction modification operon hsdMSR) were identified in three separate genomic regions that were adjacent to prophage genes, including one region containing the TonB-dependent iron siderophore receptor gene ireA, which was only found in 5 other ST127 isolates from the European Nucleotide Archive (ENA). We further identified that these isolates possessed unique virulence and metabolic genes and harbored antibiotic resistance genes, including the ESBL genes blaCTX-M-3 (n = 3), blaCTX-M-236 (n = 1), and blaTEM-1 (n = 1), in addition to a quinolone resistance protein gene qnrD1 (n = 1), which was absent in the ST127 isolates obtained from the ENA. Moreover, a plasmid replicon gene IncI2 (n = 1) was unique to ARM88 of the Armenian isolates. Our findings demonstrate that at the time of this study, E. coli ST127 was a cause of urinary tract infections in patients in different regions of Armenia, with a possibility of cross-country transmission between Armenia and France. IMPORTANCE Whole-genome sequencing studies of pathogens causing infectious diseases are seriously lacking in Armenia, hampering global efforts to track, trace and contain infectious disease outbreaks. In this study, we report for the first-time the whole-genome sequencing and analysis of ESBL UPEC ST127 isolates recovered from hospitalized patients in Armenia and compare them with other E. coli ST127 retrieved from the ENA. We found close genetic similarities of the Armenian isolates, indicating that E. coli ST127 was potentially a dominant lineage causing urinary tract infections in Armenia. Furthermore, we identified unique genes that were horizontally acquired in the clusters of Armenian and French isolates that were absent in other ST127 isolates obtained from the ENA. Our findings highlight a possible cross-country transmission between Armenia and France and the idea that the implementation of WGS surveillance could contribute to global efforts in tackling antibiotic resistance, as bacteria carrying antimicrobial resistance (AMR) genes do not recognize borders.
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21
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Dai P, Hu D. The making of hypervirulent Klebsiella pneumoniae. J Clin Lab Anal 2022; 36:e24743. [PMID: 36347819 PMCID: PMC9757020 DOI: 10.1002/jcla.24743] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 10/01/2022] [Accepted: 10/09/2022] [Indexed: 10/08/2023] Open
Abstract
Klebsiella pneumoniae is a notorious bacterium in clinical practice. Virulence, carbapenem-resistance and their convergence among K. pneumoniae are extensively discussed in this article. Hypervirulent K. pneumoniae (HvKP) has spread from the Asian Pacific Rim to the world, inducing various invasive infections, such as pyogenic liver abscess, endophthalmitis, and meningitis. Furthermore, HvKP has acquired more and more drug resistance. Among multidrug-resistant HvKP, hypervirulent carbapenem-resistant K. pneumoniae (Hv-CRKP), and carbapenem-resistant hypervirulent K. pneumoniae (CR-HvKP) are both devastating for their extreme drug resistance and virulence. The hypervirulence of HvKP is primarily attributed to hypercapsule, macromolecular exopolysaccharides, or excessive siderophores, although it has many other factors, for example, lipopolysaccharides, fimbriae, and porins. In contrast with classical determination of HvKP, that is, animal lethality test, molecular determination could be an optional and practical method after improvement. HvKP, including Hv-CRKP and CR-HvKP, has been progressing. R-M and CRISPR-Cas systems may play pivotal roles in such evolutions. Hv-CRKP and CR-HvKP, in particular the former, should be of severe concern due to their being more and more prevalent.
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Affiliation(s)
- Piaopiao Dai
- Department of Laboratory MedicineTaizhou Municipal HospitalTaizhouChina
| | - Dakang Hu
- Department of Laboratory MedicineTaizhou Municipal HospitalTaizhouChina
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22
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Molecular insights into DNA recognition and methylation by non-canonical type I restriction-modification systems. Nat Commun 2022; 13:6391. [PMID: 36302770 PMCID: PMC9613975 DOI: 10.1038/s41467-022-34085-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: 03/13/2022] [Accepted: 10/11/2022] [Indexed: 12/25/2022] Open
Abstract
Type I restriction-modification systems help establish the prokaryotic DNA methylation landscape and provide protection against invasive DNA. In addition to classical m6A modifications, non-canonical type I enzymes catalyze both m6A and m4C using alternative DNA-modification subunits M1 and M2. Here, we report the crystal structures of the non-canonical PacII_M1M2S methyltransferase bound to target DNA and reaction product S-adenosylhomocysteine in a closed clamp-like conformation. Target DNA binds tightly within the central tunnel of the M1M2S complex and forms extensive contacts with all three protein subunits. Unexpectedly, while the target cytosine properly inserts into M2's pocket, the target adenine (either unmethylated or methylated) is anchored outside M1's pocket. A unique asymmetric catalysis is established where PacII_M1M2S has precisely coordinated the relative conformations of different subunits and evolved specific amino acids within M2/M1. This work provides insights into mechanisms of m6A/m4C catalysis and guidance for designing tools based on type I restriction-modification enzymes.
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23
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Adamczyk-Poplawska M, Bacal P, Mrozek A, Matczynska N, Piekarowicz A, Kwiatek A. Phase-variable Type I methyltransferase M.NgoAV from Neisseria gonorrhoeae FA1090 regulates phasevarion expression and gonococcal phenotype. Front Microbiol 2022; 13:917639. [PMID: 36267167 PMCID: PMC9577141 DOI: 10.3389/fmicb.2022.917639] [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] [Received: 04/11/2022] [Accepted: 09/02/2022] [Indexed: 11/13/2022] Open
Abstract
The restriction-modification (RM) systems are compared to a primitive, innate, prokaryotic immune system, controlling the invasion by foreign DNA, composed of methyltransferase (MTase) and restriction endonuclease. The biological significance of RM systems extends beyond their defensive function, but the data on the regulatory role of Type I MTases are limited. We have previously characterized molecularly a non-canonical Type I RM system, NgoAV, with phase-variable specificity, encoded by Neisseria gonorrhoeae FA1090. In the current work, we have investigated the impact of methyltransferase NgoAV (M.NgoAV) activity on gonococcal phenotype and on epigenetic control of gene expression. For this purpose, we have constructed and studied genetic variants (concerning activity and specificity) within M.NgoAV locus. Deletion of M.NgoAV or switch of its specificity had an impact on phenotype of N. gonorrhoeae. Biofilm formation and planktonic growth, the resistance to antibiotics, which target bacterial peptidoglycan or other antimicrobials, and invasion of human epithelial host cells were affected. The expression of genes was deregulated in gonococcal cells with knockout M.NgoAV gene and the variant with new specificity. For the first time, the existence of a phasevarion (phase-variable regulon), directed by phase-variable Type I MTase, is demonstrated.
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Affiliation(s)
- Monika Adamczyk-Poplawska
- Department of Molecular Virology, Institute of Microbiology, Faculty of Biology, University of Warsaw, Warsaw, Poland
- *Correspondence: Monika Adamczyk-Poplawska,
| | - Pawel Bacal
- Institute of Paleobiology, Polish Academy of Sciences, Warsaw, Poland
| | - Agnieszka Mrozek
- Department of Molecular Virology, Institute of Microbiology, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Natalia Matczynska
- Department of Molecular Virology, Institute of Microbiology, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Andrzej Piekarowicz
- Department of Molecular Virology, Institute of Microbiology, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Agnieszka Kwiatek
- Department of Molecular Virology, Institute of Microbiology, Faculty of Biology, University of Warsaw, Warsaw, Poland
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24
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Biological Features and In Planta Transcriptomic Analyses of a Microviridae Phage (CLasMV1) in " Candidatus Liberibacter asiaticus". Int J Mol Sci 2022; 23:ijms231710024. [PMID: 36077424 PMCID: PMC9456138 DOI: 10.3390/ijms231710024] [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: 08/10/2022] [Revised: 08/29/2022] [Accepted: 08/30/2022] [Indexed: 11/27/2022] Open
Abstract
“Candidatus Liberibacter asiaticus” (CLas) is the causal agent of citrus Huanglongbing (HLB, also called citrus greening disease), a highly destructive disease threatening citrus production worldwide. A novel Microviridae phage (named CLasMV1) has been found to infect CLas, providing a potential therapeutic strategy for CLas/HLB control. However, little is known about the CLasMV1 biology. In this study, we analyzed the population dynamics of CLasMV1 between the insect vector of CLas, the Asian citrus psyllid (ACP, Diaphorina citri Kuwayama) and the holoparasitic dodder plant (Cuscuta campestris Yunck.); both acquired CLasMV1-infected CLas from an HLB citrus. All CLas-positive dodder samples were CLasMV1-positive, whereas only 32% of CLas-positive ACP samples were identified as CLasMV1-positive. Quantitative analyses showed a similar distribution pattern of CLasMV1 phage and CLas among eight citrus cultivars by presenting at highest abundance in the fruit pith and/or the center axis of the fruit. Transcriptome analyses revealed the possible lytic activity of CLasMV1 on CLas in fruit pith as evidenced by high-level expressions of CLasMV1 genes, and CLas genes related to cell wall biogenesis and remodeling to maintain the CLas cell envelope integrity. The up-regulation of CLas genes were involved in restriction–modification system that could involve possible phage resistance for CLas during CLasMV1 infection. In addition, the regulation of CLas genes involved in cell surface components and Sec pathway by CLasMV1 phage could be beneficial for phage infection. This study expanded our knowledge of CLasMV1 phage that will benefit further CLas phage research and HLB control.
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25
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Aziz S, Rasheed F, Akhter TS, Zahra R, König S. Microbial Proteins in Stomach Biopsies Associated with Gastritis, Ulcer, and Gastric Cancer. Molecules 2022; 27:molecules27175410. [PMID: 36080177 PMCID: PMC9458002 DOI: 10.3390/molecules27175410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 08/12/2022] [Accepted: 08/20/2022] [Indexed: 11/24/2022] Open
Abstract
(1) Background: Gastric cancer (GC) is the fourth leading cause of cancer-related deaths worldwide. Helicobacter pylori infection is a major risk factor, but other microbial species may also be involved. In the context of an earlier proteomics study of serum and biopsies of patients with gastroduodenal diseases, we explored here a simplified microbiome in these biopsies (H. pylori, Acinetobacter baumannii, Escherichia coli, Fusobacterium nucleatum, Bacteroides fragilis) on the protein level. (2) Methods: A cohort of 75 patients was divided into groups with respect to the findings of the normal gastric mucosa (NGM) and gastroduodenal disorders such as gastritis, ulcer, and gastric cancer (GC). The H. pylori infection status was determined. The protein expression analysis of the biopsy samples was carried out using high-definition mass spectrometry of the tryptic digest (label-free data-independent quantification and statistical analysis). (3) Results: The total of 304 bacterial protein matches were detected based on two or more peptide hits. Significantly regulated microbial proteins like virulence factor type IV secretion system protein CagE from H. pylori were found with more abundance in gastritis than in GC or NGM. This finding could reflect the increased microbial involvement in mucosa inflammation in line with current hypotheses. Abundant proteins across species were heat shock proteins and elongation factors. (4) Conclusions: Next to the bulk of human proteins, a number of species-specific bacterial proteins were detected in stomach biopsies of patients with gastroduodenal diseases, some of which, like those expressed by the cag pathogenicity island, may provide gateways to disease prevention without antibacterial intervention in order to reduce antibiotic resistance.
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Affiliation(s)
- Shahid Aziz
- Patients Diagnostic Lab, Isotope Application Division, Pakistan Institute of Nuclear Science and Technology (PINSTECH), Islamabad 44000, Pakistan
- Department of Microbiology, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad 45320, Pakistan
- IZKF Core Unit Proteomics, University of Münster, 48149 Münster, Germany
- Correspondence: or
| | - Faisal Rasheed
- Patients Diagnostic Lab, Isotope Application Division, Pakistan Institute of Nuclear Science and Technology (PINSTECH), Islamabad 44000, Pakistan
| | - Tayyab Saeed Akhter
- The Centre for Liver and Digestive Diseases, Holy Family Hospital, Rawalpindi 46300, Pakistan
| | - Rabaab Zahra
- Department of Microbiology, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad 45320, Pakistan
| | - Simone König
- IZKF Core Unit Proteomics, University of Münster, 48149 Münster, Germany
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26
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Metagenomic methylation patterns resolve bacterial genomes of unusual size and structural complexity. THE ISME JOURNAL 2022; 16:1921-1931. [PMID: 35459792 PMCID: PMC9296519 DOI: 10.1038/s41396-022-01242-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 04/05/2022] [Accepted: 04/08/2022] [Indexed: 01/01/2023]
Abstract
The plasticity of bacterial and archaeal genomes makes examining their ecological and evolutionary dynamics both exciting and challenging. The same mechanisms that enable rapid genomic change and adaptation confound current approaches for recovering complete genomes from metagenomes. Here, we use strain-specific patterns of DNA methylation to resolve complex bacterial genomes from long-read metagenomic data of a marine microbial consortium, the “pink berries” of the Sippewissett Marsh (USA). Unique combinations of restriction-modification (RM) systems encoded by the bacteria produced distinctive methylation profiles that were used to accurately bin and classify metagenomic sequences. Using this approach, we finished the largest and most complex circularized bacterial genome ever recovered from a metagenome (7.9 Mb with >600 transposons), the finished genome of Thiohalocapsa sp. PB-PSB1 the dominant bacteria in the consortia. From genomes binned by methylation patterns, we identified instances of horizontal gene transfer between sulfur-cycling symbionts (Thiohalocapsa sp. PB-PSB1 and Desulfofustis sp. PB-SRB1), phage infection, and strain-level structural variation. We also linked the methylation patterns of each metagenome-assembled genome with encoded DNA methyltransferases and discovered new RM defense systems, including novel associations of RM systems with RNase toxins.
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27
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Krause AL, Stinear TP, Monk IR. Barriers to genetic manipulation of Enterococci: Current Approaches and Future Directions. FEMS Microbiol Rev 2022; 46:6650352. [PMID: 35883217 PMCID: PMC9779914 DOI: 10.1093/femsre/fuac036] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 07/14/2022] [Accepted: 07/22/2022] [Indexed: 01/09/2023] Open
Abstract
Enterococcus faecalis and Enterococcus faecium are Gram-positive commensal gut bacteria that can also cause fatal infections. To study clinically relevant multi-drug resistant E. faecalis and E. faecium strains, methods are needed to overcome physical (thick cell wall) and enzymatic barriers that limit the transfer of foreign DNA and thus prevent facile genetic manipulation. Enzymatic barriers to DNA uptake identified in E. faecalis and E. faecium include type I, II and IV restriction modification systems and CRISPR-Cas. This review examines E. faecalis and E. faecium DNA defence systems and the methods with potential to overcome these barriers. DNA defence system bypass will allow the application of innovative genetic techniques to expedite molecular-level understanding of these important, but somewhat neglected, pathogens.
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Affiliation(s)
- Alexandra L Krause
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection & Immunity, Melbourne, VIC 3000 Australia
| | - Timothy P Stinear
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection & Immunity, Melbourne, VIC 3000 Australia
| | - Ian R Monk
- Corresponding author: Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection & Immunity, Melbourne, VIC 3000 Australia. E-mail:
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28
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Sprotte S, Rasmussen TS, Cho GS, Brinks E, Lametsch R, Neve H, Vogensen FK, Nielsen DS, Franz CMAP. Morphological and Genetic Characterization of Eggerthella lenta Bacteriophage PMBT5. Viruses 2022; 14:1598. [PMID: 35893664 PMCID: PMC9394477 DOI: 10.3390/v14081598] [Citation(s) in RCA: 1] [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: 03/29/2022] [Revised: 07/01/2022] [Accepted: 07/19/2022] [Indexed: 01/27/2023] Open
Abstract
Eggerthella lenta is a common member of the human gut microbiome. We here describe the isolation and characterization of a putative virulent bacteriophage having E. lenta as host. The double-layer agar method for isolating phages was adapted to anaerobic conditions for isolating bacteriophage PMBT5 from sewage on a strictly anaerobic E. lenta strain of intestinal origin. For this, anaerobically grown E. lenta cells were concentrated by centrifugation and used for a 24 h phage enrichment step. Subsequently, this suspension was added to anaerobically prepared top (soft) agar in Hungate tubes and further used in the double-layer agar method. Based on morphological characteristics observed by transmission electron microscopy, phage PMBT5 could be assigned to the Siphoviridae phage family. It showed an isometric head with a flexible, noncontractile tail and a distinct single 45 nm tail fiber under the baseplate. Genome sequencing and assembly resulted in one contig of 30,930 bp and a mol% GC content of 51.3, consisting of 44 predicted protein-encoding genes. Phage-related proteins could be largely identified based on their amino acid sequence, and a comparison with metagenomes in the human virome database showed that the phage genome exhibits similarity to two distantly related phages.
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Affiliation(s)
- Sabrina Sprotte
- Department of Microbiology and Biotechnology, Max Rubner-Institut, Federal Research Institute of Nutrition and Food, 24103 Kiel, Germany; (G.-S.C.); (E.B.); (H.N.); (C.M.A.P.F.)
| | - Torben S. Rasmussen
- Department of Food Science, Faculty of Science, University of Copenhagen, 1958 Frederiksberg, Denmark; (T.S.R.); (R.L.); (F.K.V.); (D.S.N.)
| | - Gyu-Sung Cho
- Department of Microbiology and Biotechnology, Max Rubner-Institut, Federal Research Institute of Nutrition and Food, 24103 Kiel, Germany; (G.-S.C.); (E.B.); (H.N.); (C.M.A.P.F.)
| | - Erik Brinks
- Department of Microbiology and Biotechnology, Max Rubner-Institut, Federal Research Institute of Nutrition and Food, 24103 Kiel, Germany; (G.-S.C.); (E.B.); (H.N.); (C.M.A.P.F.)
| | - René Lametsch
- Department of Food Science, Faculty of Science, University of Copenhagen, 1958 Frederiksberg, Denmark; (T.S.R.); (R.L.); (F.K.V.); (D.S.N.)
| | - Horst Neve
- Department of Microbiology and Biotechnology, Max Rubner-Institut, Federal Research Institute of Nutrition and Food, 24103 Kiel, Germany; (G.-S.C.); (E.B.); (H.N.); (C.M.A.P.F.)
| | - Finn K. Vogensen
- Department of Food Science, Faculty of Science, University of Copenhagen, 1958 Frederiksberg, Denmark; (T.S.R.); (R.L.); (F.K.V.); (D.S.N.)
| | - Dennis S. Nielsen
- Department of Food Science, Faculty of Science, University of Copenhagen, 1958 Frederiksberg, Denmark; (T.S.R.); (R.L.); (F.K.V.); (D.S.N.)
| | - Charles M. A. P. Franz
- Department of Microbiology and Biotechnology, Max Rubner-Institut, Federal Research Institute of Nutrition and Food, 24103 Kiel, Germany; (G.-S.C.); (E.B.); (H.N.); (C.M.A.P.F.)
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29
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Zhang X, Wang R, Xie X, Hu Y, Wang J, Sun Q, Feng X, Lin W, Tong S, Yan W, Wen H, Wang M, Zhai S, Sun C, Wang F, Niu Q, Kropinski A, Cui Y, Jiang X, Peng S, Li S, Tong Y. Mining bacterial NGS data vastly expands the complete genomes of temperate phages. NAR Genom Bioinform 2022; 4:lqac057. [PMID: 35937545 PMCID: PMC9346568 DOI: 10.1093/nargab/lqac057] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 06/13/2022] [Accepted: 07/20/2022] [Indexed: 11/13/2022] Open
Abstract
Abstract
Temperate phages (active prophages induced from bacteria) help control pathogenicity, modulate community structure, and maintain gut homeostasis. Complete phage genome sequences are indispensable for understanding phage biology. Traditional plaque techniques are inapplicable to temperate phages due to their lysogenicity, curbing their identification and characterization. Existing bioinformatics tools for prophage prediction usually fail to detect accurate and complete temperate phage genomes. This study proposes a novel computational temperate phage detection method (TemPhD) mining both the integrated active prophages and their spontaneously induced forms (temperate phages) from next-generation sequencing raw data. Applying the method to the available dataset resulted in 192 326 complete temperate phage genomes with different host species, expanding the existing number of complete temperate phage genomes by more than 100-fold. The wet-lab experiments demonstrated that TemPhD can accurately determine the complete genome sequences of the temperate phages, with exact flanking sites, outperforming other state-of-the-art prophage prediction methods. Our analysis indicates that temperate phages are likely to function in the microbial evolution by (i) cross-infecting different bacterial host species; (ii) transferring antibiotic resistance and virulence genes and (iii) interacting with hosts through restriction-modification and CRISPR/anti-CRISPR systems. This work provides a comprehensively complete temperate phage genome database and relevant information, which can serve as a valuable resource for phage research.
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Affiliation(s)
- Xianglilan Zhang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology , Beijing 100071, People's Republic of China
| | - Ruohan Wang
- Department of Computer Science, City University of Hong Kong , Hong Kong 999077, People's Republic of China
| | - Xiangcheng Xie
- College of Computer, National University of Defense Technology , Changsha 410073, People's Republic of China
| | - Yunjia Hu
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering (BAIC-SM), College of Life Science and Technology, Beijing University of Chemical Technology , Beijing 100029, People's Republic of China
- School of Medicine, Shanghai University , Shanghai 200444, People's Republic of China
| | - Jianping Wang
- Department of Computer Science, City University of Hong Kong , Hong Kong 999077, People's Republic of China
| | - Qiang Sun
- The 964th Hospital , Changchun 130021, People's Republic of China
| | - Xikang Feng
- School of Software, Northwestern Polytechnical University , Xi’an 710072, People's Republic of China
| | - Wei Lin
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering (BAIC-SM), College of Life Science and Technology, Beijing University of Chemical Technology , Beijing 100029, People's Republic of China
| | - Shanwei Tong
- Bioinformatics Graduate Program, University of British Columbia , Vancouver BC V6T 1Z4, Canada
- Faculty of Health Sciences, Simon Fraser University , Burnaby , BC V5A 1S6, Canada
| | - Wei Yan
- National Library of Medicine, National Institutes of Health , Bethesda , MD 20894, USA
| | - Huiqi Wen
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology , Beijing 100071, People's Republic of China
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering (BAIC-SM), College of Life Science and Technology, Beijing University of Chemical Technology , Beijing 100029, People's Republic of China
| | - Mengyao Wang
- Department of Computer Science, City University of Hong Kong , Hong Kong 999077, People's Republic of China
| | - Shixiang Zhai
- Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences , Yantai 264003, People's Republic of China
- University of Chinese Academy of Sciences , Beijing 100049, People's Republic of China
- Center for Ocean Mega-Science, Chinese Academy of Sciences , Qingdao 266071, People's Republic of China
| | - Cheng Sun
- School of Computer Science and Electronic Engineering, Hunan University , Changsha 410082, People's Republic of China
| | - Fangyi Wang
- Department of Statistics, the Ohio State University , Columbus, OH 43210, USA
| | - Qi Niu
- School of Computer Science and Electronic Engineering, Hunan University , Changsha 410082, People's Republic of China
| | - Andrew M Kropinski
- Departments of Food Science, and Pathobiology, University of Guelph , Guelph , ON N1G 2W1 , Canada
| | - Yujun Cui
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology , Beijing 100071, People's Republic of China
| | - Xiaofang Jiang
- National Library of Medicine, National Institutes of Health , Bethesda , MD 20894, USA
| | - Shaoliang Peng
- School of Computer Science and Electronic Engineering, Hunan University , Changsha 410082, People's Republic of China
| | - Shuaicheng Li
- Department of Computer Science, City University of Hong Kong , Hong Kong 999077, People's Republic of China
| | - Yigang Tong
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering (BAIC-SM), College of Life Science and Technology, Beijing University of Chemical Technology , Beijing 100029, People's Republic of China
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Structural basis for broad anti-phage immunity by DISARM. Nat Commun 2022; 13:2987. [PMID: 35624106 PMCID: PMC9142583 DOI: 10.1038/s41467-022-30673-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Accepted: 05/12/2022] [Indexed: 11/08/2022] Open
Abstract
In the evolutionary arms race against phage, bacteria have assembled a diverse arsenal of antiviral immune strategies. While the recently discovered DISARM (Defense Island System Associated with Restriction-Modification) systems can provide protection against a wide range of phage, the molecular mechanisms that underpin broad antiviral targeting but avoiding autoimmunity remain enigmatic. Here, we report cryo-EM structures of the core DISARM complex, DrmAB, both alone and in complex with an unmethylated phage DNA mimetic. These structures reveal that DrmAB core complex is autoinhibited by a trigger loop (TL) within DrmA and binding to DNA substrates containing a 5′ overhang dislodges the TL, initiating a long-range structural rearrangement for DrmAB activation. Together with structure-guided in vivo studies, our work provides insights into the mechanism of phage DNA recognition and specific activation of this widespread antiviral defense system. DISARM (Defense Island System Associated with Restriction Modification) systems can provide bacteria with protection against a wide range of phage. Here, Bravo et al. determine cryo-EM structures of the core DISARM complex that shed light onto phage DNA recognition and activation of this widespread defense system.
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Aravind L, Iyer LM, Burroughs AM. Discovering Biological Conflict Systems Through Genome Analysis: Evolutionary Principles and Biochemical Novelty. Annu Rev Biomed Data Sci 2022; 5:367-391. [PMID: 35609893 DOI: 10.1146/annurev-biodatasci-122220-101119] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Biological replicators, from genes within a genome to whole organisms, are locked in conflicts. Comparative genomics has revealed a staggering diversity of molecular armaments and mechanisms regulating their deployment, collectively termed biological conflict systems. These encompass toxins used in inter- and intraspecific interactions, self/nonself discrimination, antiviral immune mechanisms, and counter-host effectors deployed by viruses and intragenomic selfish elements. These systems possess shared syntactical features in their organizational logic and a set of effectors targeting genetic information flow through the Central Dogma, certain membranes, and key molecules like NAD+. These principles can be exploited to discover new conflict systems through sensitive computational analyses. This has led to significant advances in our understanding of the biology of these systems and furnished new biotechnological reagents for genome editing, sequencing, and beyond. We discuss these advances using specific examples of toxins, restriction-modification, apoptosis, CRISPR/second messenger-regulated systems, and other enigmatic nucleic acid-targeting systems. Expected final online publication date for the Annual Review of Biomedical Data Science, Volume 5 is August 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- L Aravind
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland, USA;
| | - Lakshminarayan M Iyer
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland, USA;
| | - A Maxwell Burroughs
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland, USA;
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Gidwani S, Heiter D, Xu SY. Expression and Purification of BsaXI Restriction Endonuclease and Engineering New Specificity From BsaXI Specificity Subunit. Front Microbiol 2022; 13:888435. [PMID: 35663886 PMCID: PMC9159934 DOI: 10.3389/fmicb.2022.888435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 03/24/2022] [Indexed: 11/13/2022] Open
Abstract
It is stated that BsaXI is a Type IIB restriction endonuclease (REase) that cleaves both sides of its recognition sequence 5′↓N9 AC N5 CTCC N10↓ 3′ (complement strand 5′ ↓N7 GGAG N5 GT N12↓ 3′), creating 3-base 3′ overhangs. Here we report the cloning and expression of bsaXIS and bsaXIRM genes in Escherichia coli. The BsaXI activity was successfully reconstituted by mixing the BsaXI RM fusion subunit with the BsaXI S subunit and the enzyme complex further purified by chromatography over 6 columns. As expected, the S subunit consisted of two subdomains encoding TRD1-CR1 [target recognition domain (TRD), conserved region (CR)] for 5′ AC 3′, and TRD2-CR2 presumably specifying 5′ CTCC 3′. TRD1-CR1 (TRD2-CR2 deletion) or duplication of TRD1 (TRD1-CR1-TRD1-CR2) both generated a new specificity 5′ AC N5 GT 3′ when the S variants were complexed with the RM subunits. The circular permutation of TRD1 and TRD2, i.e., the relocation of TRD2-CR2 to the N-terminus and TRD1-CR1 to the C-terminus generated the same specificity with the RM subunits, although some wobble cleavage was detected. The TRD2 domain in the BsaXI S subunit can be substituted by a close homolog (∼59% sequence identity) and generated the same specificity. However, TRD2-CR2 domain alone failed to express in E. coli, but CR1-TRD2-CR2 protein could be expressed and purified which showed partial nicking activity with the RM subunits. This work demonstrated that like Type I restriction systems, the S subunit of a Type IIB system could also be manipulated to create new specificities. The genome mining of BsaXI TRD2 homologs in GenBank found more than 36 orphan TRD2 homologs, implying that quite a few orphan TRD2s are present in microbial genomes that may be potentially paired with other TRDs to create new restriction specificities.
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Dordet-Frisoni E, Vandecasteele C, Contarin R, Sagné E, Baranowski E, Klopp C, Nouvel LX, Citti C. Impacts of Mycoplasma agalactiae restriction-modification systems on pan-epigenome dynamics and genome plasticity. Microb Genom 2022; 8:mgen000829. [PMID: 35576144 PMCID: PMC9465063 DOI: 10.1099/mgen.0.000829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 04/14/2022] [Indexed: 11/18/2022] Open
Abstract
DNA methylations play an important role in the biology of bacteria. Often associated with restriction modification (RM) systems, they are important drivers of bacterial evolution interfering in horizontal gene transfer events by providing a defence against foreign DNA invasion or by favouring genetic transfer through production of recombinogenic DNA ends. Little is known regarding the methylome of the Mycoplasma genus, which encompasses several pathogenic species with small genomes. Here, genome-wide detection of DNA methylations was conducted using single molecule real-time (SMRT) and bisulphite sequencing in several strains of Mycoplasma agalactiae, an important ruminant pathogen and a model organism. Combined with whole-genome analysis, this allowed the identification of 19 methylated motifs associated with three orphan methyltransferases (MTases) and eight RM systems. All systems had a homolog in at least one phylogenetically distinct Mycoplasma spp. Our study also revealed that several superimposed genetic events may participate in the M. agalactiae dynamic epigenomic landscape. These included (i) DNA shuffling and frameshift mutations that affect the MTase and restriction endonuclease content of a clonal population and (ii) gene duplication, erosion, and horizontal transfer that modulate MTase and RM repertoires of the species. Some of these systems were experimentally shown to play a major role in mycoplasma conjugative, horizontal DNA transfer. While the versatility of DNA methylation may contribute to regulating essential biological functions at cell and population levels, RM systems may be key in mycoplasma genome evolution and adaptation by controlling horizontal gene transfers.
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Affiliation(s)
- Emilie Dordet-Frisoni
- IHAP, Université de Toulouse, INRAE, ENVT, Toulouse, France
- Present address: INTHERES, Université de Toulouse, INRAE, ENVT, Toulouse, France
| | | | | | - Eveline Sagné
- IHAP, Université de Toulouse, INRAE, ENVT, Toulouse, France
| | | | - Christophe Klopp
- INRAE, UR875 MIAT, Sigenae, BioInfo Genotoul, BioInfoMics, F-31326 Auzeville, France
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Ong ZX, Kannan B, Becker DL. Exploiting transposons in the study of Staphylococcus aureus pathogenesis and virulence. Crit Rev Microbiol 2022; 49:297-317. [PMID: 35438613 DOI: 10.1080/1040841x.2022.2052794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The opportunistic pathogen Staphylococcus aureus has an extremely complex relationship with humans. While the bacteria can exist as a commensal in many, it can cause a wide range of diseases and infections when turned pathogenic. Its presence is a determinant of chronicity and poor prognosis in numerous diseases, and its genomic plasticity causes S. aureus antimicrobial resistance to be one of the most dire contemporary medical problems to solve. Genetic manipulation of S. aureus has led to numerous findings that are vital in the fight against its pathogenesis. The utilisation of transposon mutant libraries for the systematic inspection of the S. aureus genome led to many landmark discoveries pertaining to the bacteria's pathogenicity, antimicrobial resistance acquisition, and virulence regulation. In this review, we describe mutant libraries, and their significant contributions, from various S. aureus strains created with commonly used transposons. The general workflow for the construction of libraries will be presented, along with a discussion of the challenges of undertaking the task of large-scale library construction. As the accessibility of transposon mutant library construction, screening, and analysis increases, this genetic tool could be further exploited in the study of the S. aureus genome.
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Affiliation(s)
- Zi Xin Ong
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore.,Skin Research Institute, Singapore.,Nanyang Institute of Technology in Health and Medicine, Interdisciplinary Graduate Programme, Nanyang Technological University, Singapore
| | - Bavani Kannan
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore.,Skin Research Institute, Singapore
| | - David L Becker
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore.,Skin Research Institute, Singapore
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35
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Santos HSDB, Do T, Parolo CCF, Poloni JDF, Maltz M, Arthur RA, Damé-Teixeira N. Streptococcus mutans gene expression and functional profile in root caries: an RNA-seq study. Caries Res 2022; 56:116-128. [DOI: 10.1159/000524196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 03/20/2022] [Indexed: 11/19/2022] Open
Abstract
The literature is still scarce on studies describing S. mutans global gene expression under clinical conditions such as those found on complex biofilms from sound root surfaces (SRS) and carious root surfaces (RC). This study aimed to investigate the S. mutans gene expression and functional profile within the metatranscriptome of biofilms from SRS and from RC in an attempt to identify enriched functional signatures potentially associated with healthy to disease transitioning process. Total RNA was extracted, and prepared libraries (SRS=10 and RC=9) were paired-end sequenced using the Illumina HiSeq2500. Read count assigned to each gene of the S. mutans UA159 strain were obtained. Differentially expressed genes (DEG) between SRS and RC were identified using the DESeq2 R package and weighted gene co-expression network analysis (WGCNA) was performed to explore and identify functional modules related to SRS and RC. We found seventeen DEG between SRS and RC samples, with three overexpressed in RC and related to membrane protein, alanyl-tRNA synthetase and GTP-binding protein with the remaining ones overexpressed in SRS samples and related to hypothetical protein, transposon integrase, histidine kinase, putative transporter, bacteriocin immunity protein, response regulator, 6-phospho-beta-galactosidase, purine metabolism and to transcriptional regulator. Key-functional modules were identified for SRS and RC conditions based on WCGNA, being 139 hub genes found on SRS key-module and 17 genes on RC key-module. Functional analysis of S. mutans within the metatranscriptome of biofilms from sound root and from carious root revealed a similar pattern of gene expression, and only a few genes have been differentially expressed between biofilms from sound root surfaces and from root carious lesions. However, S. mutans presented a greater functional abundance in the lesion samples. Some functional patterns related to sugar (starch, sucrose, fructose, mannose and lactose) and heterofermentative metabolisms, to cell-wall biosynthesis and to acid tolerance stress seem to be enriched on carious root surfaces conferring ecological advantages to S. mutans. Altogether, the present data suggest that a functional signature may be associated with carious root lesions.
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Seo PW, Hofmann A, Kim JH, Hwangbo SA, Kim JH, Kim JW, Huynh TYL, Choy HE, Kim SJ, Lee J, Lee JO, Jin KS, Park SY, Kim JS. Structural features of a minimal intact methyltransferase of a type I restriction-modification system. Int J Biol Macromol 2022; 208:381-389. [PMID: 35337914 DOI: 10.1016/j.ijbiomac.2022.03.115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 03/16/2022] [Accepted: 03/17/2022] [Indexed: 11/05/2022]
Abstract
Type I restriction-modification enzymes are oligomeric proteins composed of methylation (M), DNA sequence-recognition (S), and restriction (R) subunits. The different bipartite DNA sequences of 2-4 consecutive bases are recognized by two discerned target recognition domains (TRDs) located at the two-helix bundle of the two conserved regions (CRs). Two M-subunits and a single S-subunit form an oligomeric protein that functions as a methyltransferase (M2S1 MTase). Here, we present the crystal structure of the intact MTase from Vibrio vulnificus YJ016 in complex with the DNA-mimicking Ocr protein and the S-adenosyl-L-homocysteine (SAH). This MTase includes the M-domain with a helix tail (M-tail helix) and the S1/2-domain of a TRD and a CR α-helix. The Ocr binds to the cleft of the TRD surface and SAH is located in the pocket within the M-domain. The solution- and negative-staining electron microscopy-based reconstructed (M1S1/2)2 structure reveals a symmetric (S1/2)2 assembly using two CR-helices and two M-tail helices as a pivot, which is plausible for recognizing two DNA regions of same sequence. The conformational flexibility of the minimal M1S1/2 MTase dimer indicates a particular state resembling the structure of M2S1 MTases.
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Affiliation(s)
- Pil-Won Seo
- Department of Chemistry, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Andreas Hofmann
- Department of Veterinary Biosciences, Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria 3010, Australia; Max Rubner-Institut, Federal Research Institute of Nutrition and Food, 95326 Kulmbach, Germany
| | - Jun-Ha Kim
- Pohang Accelerator Laboratory, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Republic of Korea; Department of Chemical Engineering, Kumoh National Institute of Technology, 61, Daehak-ro, Gumi, Gyeongbuk 39177, Republic of Korea
| | - Seung-A Hwangbo
- Pohang Accelerator Laboratory, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Republic of Korea; Department of Life Sciences and Institute of Membrane Proteins, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Jun-Hong Kim
- Department of Chemistry, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Ji-Won Kim
- Department of Chemistry, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Thi Yen Ly Huynh
- Department of Chemistry, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Hyon E Choy
- Department of Microbiology, Basic Medical Research Building, Chonnam National University Medical College, Hwasun, Jeonnam 58128, Republic of Korea
| | - Soo-Jung Kim
- Department of Integrative Food, Bioscience and Biotechnology, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Jimin Lee
- Department of Life Sciences and Institute of Membrane Proteins, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Jie-Oh Lee
- Department of Life Sciences and Institute of Membrane Proteins, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Kyeong Sik Jin
- Pohang Accelerator Laboratory, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Republic of Korea.
| | - Suk-Youl Park
- Pohang Accelerator Laboratory, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Republic of Korea.
| | - Jeong-Sun Kim
- Department of Chemistry, Chonnam National University, Gwangju 61186, Republic of Korea.
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Genomic Features and Pervasive Negative Selection in Rhodanobacter Strains Isolated from Nitrate and Heavy Metal Contaminated Aquifer. Microbiol Spectr 2022; 10:e0259121. [PMID: 35107332 PMCID: PMC8809349 DOI: 10.1128/spectrum.02591-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Rhodanobacter species dominate in the Oak Ridge Reservation (ORR) subsurface environments contaminated with acids, nitrate, metal radionuclides, and other heavy metals. To uncover the genomic features underlying adaptations to these mixed-waste environments and to guide genetic tool development, we sequenced the whole genomes of eight Rhodanobacter strains isolated from the ORR site. The genome sizes ranged from 3.9 to 4.2 Mb harboring 3,695 to 4,035 protein-coding genes and GC contents approximately 67%. Seven strains were classified as R. denitrificans and one strain, FW510-R12, as R. thiooxydans based on full length 16S rRNA sequences. According to gene annotation, the top two Cluster of Orthologous Groups (COGs) with high pan-genome expansion rates (Pan/Core gene ratio) were “replication, recombination and repair” and “defense mechanisms.” The denitrifying genes had high DNA homologies except the predicted protein structure variances in NosZ. In contrast, heavy metal resistance genes were diverse with between 7 to 34% of them were located in genomic islands, and these results suggested origins from horizontal gene transfer. Analysis of the methylation patterns in four strains revealed the unique 5mC methylation motifs. Most orthologs (78%) had ratios of nonsynonymous to synonymous substitutions (dN/dS) less than one when compared to the type strain 2APBS1, suggesting the prevalence of negative selection. Overall, the results provide evidence for the important roles of horizontal gene transfer and negative selection in genomic adaptation at the contaminated field site. The complex restriction-modification system genes and the unique methylation motifs in Rhodanobacter strains suggest the potential recalcitrance to genetic manipulation. IMPORTANCE Despite the dominance of Rhodanobacter species in the subsurface of the contaminated Oak Ridge Reservation (ORR) site, very little is known about the mechanisms underlying their adaptions to the various stressors present at ORR. Recently, multiple Rhodanobacter strains have been isolated from the ORR groundwater samples from several wells with varying geochemical properties. Using Illumina, PacBio, and Oxford Nanopore sequencing platforms, we obtained the whole genome sequences of eight Rhodanobacter strains. Comparison of the whole genomes demonstrated the genetic diversity, and analysis of the long nanopore reads revealed the heterogeneity of methylation patterns in strains isolated from the same well. Although all strains contained a complete set of denitrifying genes, the predicted tertiary structures of NosZ differed. The sequence comparison results demonstrate the important roles of horizontal gene transfer and negative selection in adaptation. In addition, these strains may be recalcitrant to genetic manipulation due to the complex restriction-modification systems and methylations.
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Li D, Li P, Peng M, Zhao X, Jiang X, Wang D, Yuan Y, Guo Q, Wang M, Xu X, Wang M. Transmission barrier of the blaKPC plasmid mediated by type I restriction-modification systems in Escherichia coli. J Antimicrob Chemother 2022; 77:952-956. [PMID: 35040978 DOI: 10.1093/jac/dkab489] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 12/06/2021] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Transportation of carbapenem-resistant plasmids contributes to carbapenem resistance in Gram-negative bacteria. KPC enzymes are the most clinically important enzymes among carbapenem-resistant Klebsiella pneumoniae, whereas the rate of blaKPC in Escherichia coli is low. The CRISPR-Cas system and restriction-modification system (R-M system) in bacteria defend against invading genomes. Currently, the role of the immune systems in the low rate of KPC-producing E. coli remains unclear. OBJECTIVES We investigated the relationship between immune systems and the low detection rate of blaKPC in E. coli. METHODS We searched for blaKPC among 1039 E. coli whole genomes available in GenBank using nucleotide BLAST. CRISPR-Cas systems and the R-M system were detected in all strains having the ST as blaKPC-positive strains. Nucleotide BLAST was used to search for protospacers on blaKPC plasmids. A conjugation assay was performed to determine whether the R-M system influences the acquisition of blaKPC plasmids by E. coli. RESULTS ST131 was the dominant ST of KPC-producing E. coli and IncN was the main plasmid type (12/32). CRISPR-Cas systems were frequently present in E. coli carrying blaKPC. Furthermore, CRISPR-Cas systems in E. coli didn't target plasmids with blaKPC. Type I R-M systems were rare in KPC-producing E. coli, but significantly over-represented in KPC-negative strains. E. coli DH5α with hsdR deletion accepted blaKPC-carrying plasmids, whereas those with hsdR complementation impeded blaKPC-carrying plasmid conjugation. CONCLUSIONS Horizontal transmission of blaKPC occurs among E. coli. The type I R-M system is associated with the defence against blaKPC plasmid transport into E. coli.
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Affiliation(s)
- Dan Li
- Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, People's Republic of China.,Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, People's Republic of China
| | - Pei Li
- Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, People's Republic of China.,Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, People's Republic of China
| | - Mingjia Peng
- Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, People's Republic of China.,Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, People's Republic of China
| | - Xiaoyu Zhao
- Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, People's Republic of China.,Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, People's Republic of China
| | - Xiaoying Jiang
- The First Department of Critical Care Medicine, Gansu Provincial Hospital, Gansu, People's Republic of China
| | - Dongliang Wang
- The First Department of Critical Care Medicine, Gansu Provincial Hospital, Gansu, People's Republic of China
| | - Yuan Yuan
- The First Department of Critical Care Medicine, Gansu Provincial Hospital, Gansu, People's Republic of China
| | - Qinglan Guo
- Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, People's Republic of China.,Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, People's Republic of China
| | - Minghua Wang
- Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, People's Republic of China.,Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, People's Republic of China
| | - Xiaogang Xu
- Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, People's Republic of China.,Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, People's Republic of China
| | - Minggui Wang
- Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, People's Republic of China.,Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, People's Republic of China
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Characterization of the Type I Restriction Modification System Broadly Conserved among Group A Streptococci. mSphere 2021; 6:e0079921. [PMID: 34787444 PMCID: PMC8597746 DOI: 10.1128/msphere.00799-21] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Although prokaryotic DNA methylation investigations have long focused on immunity against exogenous DNA, it has been recently recognized that DNA methylation impacts gene expression and phase variation in Streptococcus pneumoniae and Streptococcus suis. A comprehensive analysis of DNA methylation is lacking for beta-hemolytic streptococci, and thus we sought to examine DNA methylation in the major human pathogen group A Streptococcus (GAS). Using a database of 224 GAS genomes encompassing 80 emm types, we found that nearly all GAS strains encode a type I restriction modification (RM) system that lacks the hsdS′ alleles responsible for impacting gene expression in S. pneumoniae and S. suis. The GAS type I system is located on the core chromosome, while sporadically present type II orphan methyltransferases were identified on prophages. By combining single-molecule real-time (SMRT) analyses of 10 distinct emm types along with phylogenomics of 224 strains, we were able to assign 13 methylation patterns to the GAS population. Inactivation of the type I RM system, occurring either naturally through phage insertion or through laboratory-induced gene deletion, abrogated DNA methylation detectable via either SMRT or MinION sequencing. Contrary to a previous report, inactivation of the type I system did not impact transcript levels of the gene (mga) encoding the key multigene activator protein (Mga) or Mga-regulated genes. Inactivation of the type I system significantly increased plasmid transformation rates. These data delineate the breadth of the core chromosomal type I RM system in the GAS population and clarify its role in immunity rather than impacting Mga regulon expression. IMPORTANCE The advent of whole-genome approaches capable of detecting DNA methylation has markedly expanded appreciation of the diverse roles of epigenetic modification in prokaryotic physiology. For example, recent studies have suggested that DNA methylation impacts gene expression in some streptococci. The data described herein are from the first systematic analysis of DNA methylation in a beta-hemolytic streptococcus and one of the few analyses to comprehensively characterize DNA methylation across hundreds of strains of the same bacterial species. We clarify that DNA methylation in group A Streptococcus (GAS) is primarily due to a type I restriction modification (RM) system present in the core genome and does not impact mga-regulated virulence gene expression, but does impact immunity against exogenous DNA. The identification of the DNA motifs recognized by each type I RM system may assist with optimizing methods for GAS genetic manipulation and help us understand how bacterial pathogens acquire exogenous DNA elements.
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Recent Molecular Tools for the Genetic Manipulation of Highly Industrially Important Mucoromycota Fungi. J Fungi (Basel) 2021; 7:jof7121061. [PMID: 34947043 PMCID: PMC8705501 DOI: 10.3390/jof7121061] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/27/2021] [Accepted: 12/06/2021] [Indexed: 12/20/2022] Open
Abstract
Mucorales is the largest and most well-studied order of the phylum Mucormycota and is known for its rapid growth rate and various industrial applications. The Mucorales fungi are a fascinating group of filamentous organisms with many uses in research and the industrial and medical fields. They are widely used biotechnological producers of various secondary metabolites and other value-added products. Certain members of Mucorales are extensively used as model organisms for genetic and molecular investigation and have extended our understanding of the metabolisms of other members of this order as well. Compared with other fungal species, our understanding of Mucoralean fungi is still in its infancy, which could be linked to their lack of effective genetic tools. However, recent advancements in molecular tools and approaches, such as the construction of recyclable markers, silencing vectors, and the CRISPR-Cas9-based gene-editing system, have helped us to modify the genomes of these model organisms. Multiple genetic modifications have been shown to generate valuable products on a large scale and helped us to understand the morphogenesis, basic biology, pathogenesis, and host–pathogen interactions of Mucoralean fungi. In this review, we discuss various conventional and modern genetic tools and approaches used for efficient gene modification in industrially important members of Mucorales.
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Ren J, Lee HM, Shen J, Na D. Advanced biotechnology using methyltransferase and its applications in bacteria: a mini review. Biotechnol Lett 2021; 44:33-44. [PMID: 34820721 DOI: 10.1007/s10529-021-03208-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 11/12/2021] [Indexed: 11/26/2022]
Abstract
Since prokaryotic restriction-modification (RM) systems protect the host by cleaving foreign DNA by restriction endonucleases, it is difficult to introduce engineered plasmid DNAs into newly isolated microorganisms whose RM system is not discovered. The prokaryotes also possess methyltransferases to protect their own DNA from the endonucleases. As those methyltransferases can be utilized to methylate engineered plasmid DNAs before transformation and to enhance the stability within the cells, the study on methyltransferases in newly isolated bacteria is essential for genetic engineering. Here, we introduce the mechanism of the RM system, specifically the methyltransferases and their biotechnological applications. These biotechnological strategies could facilitate plasmid DNA-based genetic engineering in bacteria strains that strongly defend against foreign DNA.
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Affiliation(s)
- Jun Ren
- Department of Biomedical Engineering, Chung-Ang University, Seoul, 06974, Republic of Korea
| | - Hyang-Mi Lee
- Department of Biomedical Engineering, Chung-Ang University, Seoul, 06974, Republic of Korea
| | - JunHao Shen
- Department of Biomedical Engineering, Chung-Ang University, Seoul, 06974, Republic of Korea
| | - Dokyun Na
- Department of Biomedical Engineering, Chung-Ang University, Seoul, 06974, Republic of Korea.
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42
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Chen Z, Shen M, Mao C, Wang C, Yuan P, Wang T, Sun D. A Type I Restriction Modification System Influences Genomic Evolution Driven by Horizontal Gene Transfer in Paenibacillus polymyxa. Front Microbiol 2021; 12:709571. [PMID: 34413842 PMCID: PMC8370563 DOI: 10.3389/fmicb.2021.709571] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 06/29/2021] [Indexed: 11/13/2022] Open
Abstract
Considered a “Generally Recognized As Safe” (GRAS) bacterium, the plant growth–promoting rhizobacterium Paenibacillus polymyxa has been widely applied in agriculture and animal husbandry. It also produces valuable compounds that are used in medicine and industry. Our previous work showed the presence of restriction modification (RM) system in P. polymyxa ATCC 842. Here, we further analyzed its genome and methylome by using SMRT sequencing, which revealed the presence of a larger number of genes, as well as a plasmid documented as a genomic region in a previous report. A number of mobile genetic elements (MGEs), including 78 insertion sequences, six genomic islands, and six prophages, were identified in the genome. A putative lysozyme-encoding gene from prophage P6 was shown to express lysin which caused cell lysis. Analysis of the methylome and genome uncovered a pair of reverse-complementary DNA methylation motifs which were widespread in the genome, as well as genes potentially encoding their cognate type I restriction-modification system PpoAI. Further genetic analysis confirmed the function of PpoAI as a RM system in modifying and restricting DNA. The average frequency of the DNA methylation motifs in MGEs was lower than that in the genome, implicating a role of PpoAI in restricting MGEs during genomic evolution of P. polymyxa. Finally, comparative analysis of R, M, and S subunits of PpoAI showed that homologs of the PpoAI system were widely distributed in species belonging to other classes of Firmicute, implicating a role of the ancestor of PpoAI in the genomic evolution of species beyond Paenibacillus.
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Affiliation(s)
- Ziyan Chen
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, China
| | - Minjia Shen
- UMR 9198 Institut de Biologie Intégrative de la Cellule (I2BC), Gif-sur-Yvette, France
| | - Chengyao Mao
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, China
| | - Chenyu Wang
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, China
| | - Panhong Yuan
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, China
| | - Tingzhang Wang
- Key Laboratory of Microbial Technology and Bioinformatics, Hangzhou, China
| | - Dongchang Sun
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, China
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Mehershahi KS, Chen SL. DNA methylation by three Type I restriction modification systems of Escherichia coli does not influence gene regulation of the host bacterium. Nucleic Acids Res 2021; 49:7375-7388. [PMID: 34181709 PMCID: PMC8287963 DOI: 10.1093/nar/gkab530] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 06/01/2021] [Accepted: 06/22/2021] [Indexed: 12/13/2022] Open
Abstract
DNA methylation is a common epigenetic mark that influences transcriptional regulation, and therefore cellular phenotype, across all domains of life. In particular, both orphan methyltransferases and those from phasevariable restriction modification systems (RMSs) have been co-opted to regulate virulence epigenetically in many bacteria. We now show that three distinct non-phasevariable Type I RMSs in Escherichia coli have no measurable impact on gene expression, in vivo virulence, or any of 1190 in vitro growth phenotypes. We demonstrated this using both Type I RMS knockout mutants as well as heterologous installation of Type I RMSs into two E. coli strains. These data provide three clear and currently rare examples of restriction modification systems that have no impact on their host organism’s gene regulation. This leads to the possibility that other such nonregulatory methylation systems may exist, broadening our view of the potential role that RMSs may play in bacterial evolution.
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Affiliation(s)
- Kurosh S Mehershahi
- NUHS Infectious Diseases Translational Research Programme, Department of Medicine, Division of Infectious Diseases, Yong Loo Lin School of Medicine, Singapore 119228
| | - Swaine L Chen
- NUHS Infectious Diseases Translational Research Programme, Department of Medicine, Division of Infectious Diseases, Yong Loo Lin School of Medicine, Singapore 119228.,Laboratory of Bacterial Genomics, Genome Institute of Singapore, Singapore 138672
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44
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SAMase of Bacteriophage T3 Inactivates Escherichia coli's Methionine S-Adenosyltransferase by Forming Heteropolymers. mBio 2021; 12:e0124221. [PMID: 34340545 PMCID: PMC8406200 DOI: 10.1128/mbio.01242-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
S-Adenosylmethionine lyase (SAMase) of bacteriophage T3 degrades the intracellular SAM pools of the host Escherichia coli cells, thereby inactivating a crucial metabolite involved in a plethora of cellular functions, including DNA methylation. SAMase is the first viral protein expressed upon infection, and its activity prevents methylation of the T3 genome. Maintenance of the phage genome in a fully unmethylated state has a profound effect on the infection strategy. It allows T3 to shift from a lytic infection under normal growth conditions to a transient lysogenic infection under glucose starvation. Using single-particle cryoelectron microscopy (cryo-EM) and biochemical assays, we demonstrate that SAMase performs its function by not only degrading SAM but also by interacting with and efficiently inhibiting the host's methionine S-adenosyltransferase (MAT), the enzyme that produces SAM. Specifically, SAMase triggers open-ended head-to-tail assembly of E. coli MAT into an unusual linear filamentous structure in which adjacent MAT tetramers are joined by two SAMase dimers. Molecular dynamics simulations together with normal mode analyses suggest that the entrapment of MAT tetramers within filaments leads to an allosteric inhibition of MAT activity due to a shift to low-frequency, high-amplitude active-site-deforming modes. The amplification of uncorrelated motions between active-site residues weakens MAT's substrate binding affinity, providing a possible explanation for the observed loss of function. We propose that the dual function of SAMase as an enzyme that degrades SAM and as an inhibitor of MAT activity has emerged to achieve an efficient depletion of the intracellular SAM pools. IMPORTANCE Self-assembly of enzymes into filamentous structures in response to specific metabolic cues has recently emerged as a widespread strategy of metabolic regulation. In many instances, filamentation of metabolic enzymes occurs in response to starvation and leads to functional inactivation. Here, we report that bacteriophage T3 modulates the metabolism of the host E. coli cells by recruiting a similar strategy: silencing a central metabolic enzyme by subjecting it to phage-mediated polymerization. This observation points to an intriguing possibility that virus-induced polymerization of the host metabolic enzymes is a common mechanism implemented by viruses to metabolically reprogram and subdue infected cells.
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Zhang WJ, Zhang C, Zhou S, Li XG, Mangenot S, Fouteau S, Guerin T, Qi XQ, Yang J, Bartlett DH, Wu LF. Comparative genomic analysis of obligately piezophilic Moritella yayanosii DB21MT-5 reveals bacterial adaptation to the Challenger Deep, Mariana Trench. Microb Genom 2021; 7:000591. [PMID: 34319226 PMCID: PMC8477399 DOI: 10.1099/mgen.0.000591] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 04/20/2021] [Indexed: 01/19/2023] Open
Abstract
Hadal trenches are the deepest but underexplored ecosystems on the Earth. Inhabiting the trench bottom is a group of micro-organisms termed obligate piezophiles that grow exclusively under high hydrostatic pressures (HHP). To reveal the genetic and physiological characteristics of their peculiar lifestyles and microbial adaptation to extreme high pressures, we sequenced the complete genome of the obligately piezophilic bacterium Moritella yayanosii DB21MT-5 isolated from the deepest oceanic sediment at the Challenger Deep, Mariana Trench. Through comparative analysis against pressure sensitive and deep-sea piezophilic Moritella strains, we identified over a hundred genes that present exclusively in hadal strain DB21MT-5. The hadal strain encodes fewer signal transduction proteins and secreted polysaccharases, but has more abundant metal ion transporters and the potential to utilize plant-derived saccharides. Instead of producing osmolyte betaine from choline as other Moritella strains, strain DB21MT-5 ferments on choline within a dedicated bacterial microcompartment organelle. Furthermore, the defence systems possessed by DB21MT-5 are distinct from other Moritella strains but resemble those in obligate piezophiles obtained from the same geographical setting. Collectively, the intensive comparative genomic analysis of an obligately piezophilic strain Moritella yayanosii DB21MT-5 demonstrates a depth-dependent distribution of energy metabolic pathways, compartmentalization of important metabolism and use of distinct defence systems, which likely contribute to microbial adaptation to the bottom of hadal trench.
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Affiliation(s)
- Wei-Jia Zhang
- Laboratory of Deep-Sea Microbial Cell Biology, Institute of Deep-Sea Science and Engineering, Chinese Academy of Sciences, PR China
- France-China Joint Laboratory for Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), Marseille, France / IDSSE-CAS, Sanya, PR China
- Institution of Deep-Sea Life Sciences, Hainan Deep-Sea Technology Laboratory, Sanya, PR China
| | - Chan Zhang
- Laboratory of Deep-Sea Microbial Cell Biology, Institute of Deep-Sea Science and Engineering, Chinese Academy of Sciences, PR China
- Present address: College of Horticulture, Hainan University, No. 58, Renmin Avenue, Haikou, PR China
| | - Siyu Zhou
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China
| | - Xue-Gong Li
- Laboratory of Deep-Sea Microbial Cell Biology, Institute of Deep-Sea Science and Engineering, Chinese Academy of Sciences, PR China
- France-China Joint Laboratory for Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), Marseille, France / IDSSE-CAS, Sanya, PR China
- Institution of Deep-Sea Life Sciences, Hainan Deep-Sea Technology Laboratory, Sanya, PR China
| | - Sophie Mangenot
- Génomique Métabolique, CEA, Genoscope, Institut François Jacob, Université d’Évry, Université Paris-Saclay, CNRS, Evry, France
| | - Stéphanie Fouteau
- Génomique Métabolique, CEA, Genoscope, Institut François Jacob, Université d’Évry, Université Paris-Saclay, CNRS, Evry, France
| | - Thomas Guerin
- Génomique Métabolique, CEA, Genoscope, Institut François Jacob, Université d’Évry, Université Paris-Saclay, CNRS, Evry, France
| | - Xiao-Qing Qi
- Laboratory of Deep-Sea Microbial Cell Biology, Institute of Deep-Sea Science and Engineering, Chinese Academy of Sciences, PR China
- France-China Joint Laboratory for Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), Marseille, France / IDSSE-CAS, Sanya, PR China
- Institution of Deep-Sea Life Sciences, Hainan Deep-Sea Technology Laboratory, Sanya, PR China
| | - Jian Yang
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China
| | - Douglas H. Bartlett
- Marine Biology Research Division, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA 92093-0202, USA
| | - Long-Fei Wu
- France-China Joint Laboratory for Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), Marseille, France / IDSSE-CAS, Sanya, PR China
- Aix-Marseille Université, CNRS, LCB UMR 7257, IMM, IM2B, Marseille, France
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46
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Isaev AB, Musharova OS, Severinov KV. Microbial Arsenal of Antiviral Defenses - Part I. BIOCHEMISTRY (MOSCOW) 2021; 86:319-337. [PMID: 33838632 DOI: 10.1134/s0006297921030081] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Bacteriophages or phages are viruses that infect bacterial cells (for the scope of this review we will also consider viruses that infect Archaea). Constant threat of phage infection is a major force that shapes evolution of the microbial genomes. To withstand infection, bacteria had evolved numerous strategies to avoid recognition by phages or to directly interfere with phage propagation inside the cell. Classical molecular biology and genetic engineering have been deeply intertwined with the study of phages and host defenses. Nowadays, owing to the rise of phage therapy, broad application of CRISPR-Cas technologies, and development of bioinformatics approaches that facilitate discovery of new systems, phage biology experiences a revival. This review describes variety of strategies employed by microbes to counter phage infection, with a focus on novel systems discovered in recent years. First chapter covers defense associated with cell surface, role of small molecules, and innate immunity systems relying on DNA modification.
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Affiliation(s)
- Artem B Isaev
- Skolkovo Institute of Science and Technology, Moscow, 143028, Russia.
| | - Olga S Musharova
- Skolkovo Institute of Science and Technology, Moscow, 143028, Russia. .,Institute of Molecular Genetics, Moscow, 119334, Russia
| | - Konstantin V Severinov
- Skolkovo Institute of Science and Technology, Moscow, 143028, Russia. .,Waksman Institute of Microbiology, Piscataway, NJ 08854, USA
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47
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Finn MB, Ramsey KM, Tolliver HJ, Dove SL, Wessels MR. Improved transformation efficiency of group A Streptococcus by inactivation of a type I restriction modification system. PLoS One 2021; 16:e0248201. [PMID: 33914767 PMCID: PMC8084154 DOI: 10.1371/journal.pone.0248201] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Accepted: 04/12/2021] [Indexed: 12/12/2022] Open
Abstract
Streptococcus pyogenes or group A Streptococcus (GAS) is a leading cause of bacterial pharyngitis, skin and soft tissue infections, life-threatening invasive infections, and the post-infectious autoimmune syndromes of acute rheumatic fever and post-streptococcal glomerulonephritis. Genetic manipulation of this important pathogen is complicated by resistance of the organism to genetic transformation. Very low transformation efficiency is attributed to recognition and degradation of introduced foreign DNA by a type I restriction-modification system encoded by the hsdRSM locus. DNA sequence analysis of this locus in ten GAS strains that had been previously transformed with an unrelated plasmid revealed that six of the ten harbored a spontaneous mutation in hsdR, S, or M. The mutations were all different, and at least five of the six were predicted to result in loss of function of the respective hsd gene product. The unexpected occurrence of such mutations in previously transformed isolates suggested that the process of transformation selects for spontaneous inactivating mutations in the Hsd system. We investigated the possibility of exploiting the increased transformability of hsd mutants by constructing a deletion mutation in hsdM in GAS strain 854, a clinical isolate representative of the globally dominant M1T1 clonal group. Mutant strain 854ΔhsdM exhibited a 5-fold increase in electrotransformation efficiency compared to the wild type parent strain and no obvious change in growth or off-target gene expression. We conclude that genetic transformation of GAS selects for spontaneous mutants in the hsdRSM restriction modification system. We propose that use of a defined hsdM mutant as a parent strain for genetic manipulation of GAS will enhance transformation efficiency and reduce the likelihood of selecting spontaneous hsd mutants with uncharacterized genotypes.
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Affiliation(s)
- Meredith B. Finn
- Division of Infectious Diseases, Boston Children’s Hospital and Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Kathryn M. Ramsey
- Departments of Cell and Molecular Biology and Biomedical and Pharmaceutical Sciences, University of Rhode Island, Kingston, Rhode Island, United States of America
| | - Hunter J. Tolliver
- Division of Infectious Diseases, Boston Children’s Hospital and Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Simon L. Dove
- Division of Infectious Diseases, Boston Children’s Hospital and Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Michael R. Wessels
- Division of Infectious Diseases, Boston Children’s Hospital and Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail:
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48
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Genomes of Gut Bacteria from Nasonia Wasps Shed Light on Phylosymbiosis and Microbe-Assisted Hybrid Breakdown. mSystems 2021; 6:6/2/e01342-20. [PMID: 33824199 PMCID: PMC8547009 DOI: 10.1128/msystems.01342-20] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Phylosymbiosis is a cross-system trend whereby microbial community relationships recapitulate the host phylogeny. In Nasonia parasitoid wasps, phylosymbiosis occurs throughout development, is distinguishable between sexes, and benefits host development and survival. Moreover, the microbiome shifts in hybrids as a rare Proteus bacterium in the microbiome becomes dominant. The larval hybrids then catastrophically succumb to bacterium-assisted lethality and reproductive isolation between the species. Two important questions for understanding phylosymbiosis and bacterium-assisted lethality in hybrids are (i) do the Nasonia bacterial genomes differ from other animal isolates and (ii) are the hybrid bacterial genomes the same as those in the parental species? Here, we report the cultivation, whole-genome sequencing, and comparative analyses of the most abundant gut bacteria in Nasonia larvae, Providencia rettgeri and Proteus mirabilis. Characterization of new isolates shows Proteus mirabilis forms a more robust biofilm than Providencia rettgeri and that, when grown in coculture, Proteus mirabilis significantly outcompetes Providencia rettgeri. Providencia rettgeri genomes from Nasonia are similar to each other and more divergent from pathogenic, human associates. Proteus mirabilis from Nasonia vitripennis, Nasonia giraulti, and their hybrid offspring are nearly identical and relatively distinct from human isolates. These results indicate that members of the larval gut microbiome within Nasonia are most similar to each other, and the strain of the dominant Proteus mirabilis in hybrids is resident in parental species. Holobiont interactions between shared, resident members of the wasp microbiome and the host underpin phylosymbiosis and hybrid breakdown. IMPORTANCE Animal and plant hosts often establish intimate relationships with their microbiomes. In varied environments, closely related host species share more similar microbiomes, a pattern termed phylosymbiosis. When phylosymbiosis is functionally significant and beneficial, microbial transplants between host species and host hybridization can have detrimental consequences on host biology. In the Nasonia parasitoid wasp genus, which contains a phylosymbiotic gut community, both effects occur and provide evidence for selective pressures on the holobiont. Here, we show that bacterial genomes in Nasonia differ from other environments and harbor genes with unique functions that may regulate phylosymbiotic relationships. Furthermore, the bacteria in hybrids are identical to those in parental species, thus supporting a hologenomic tenet that the same members of the microbiome and the host genome impact phylosymbiosis, hybrid breakdown, and speciation.
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49
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Abstract
Restriction enzymes provided the foundation on which molecular cloning was built, and they remain as essential tools in current recombinant DNA technology. The three classes of restriction enzymes and their features are introduced here.
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50
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Spadar A, Perdigão J, Phelan J, Charleston J, Modesto A, Elias R, de Sessions PF, Hibberd ML, Campino S, Duarte A, Clark TG. Methylation analysis of Klebsiella pneumoniae from Portuguese hospitals. Sci Rep 2021; 11:6491. [PMID: 33753763 PMCID: PMC7985491 DOI: 10.1038/s41598-021-85724-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 02/11/2021] [Indexed: 12/13/2022] Open
Abstract
Klebsiella pneumoniae is an important nosocomial infectious agent with a high antimicrobial resistance (AMR) burden. The application of long read sequencing technologies is providing insights into bacterial chromosomal and putative extra-chromosomal genetic elements (PEGEs) associated with AMR, but also epigenetic DNA methylation, which is thought to play a role in cleavage of foreign DNA and expression regulation. Here, we apply the PacBio sequencing platform to eight Portuguese hospital isolates, including one carbapenemase producing isolate, to identify methylation motifs. The resulting assembled chromosomes were between 5.2 and 5.5Mbp in length, and twenty-six PEGEs were found. Four of our eight samples carry blaCTX-M-15, a dominant Extended Spectrum Beta Lactamase in Europe. We identified methylation motifs that control Restriction-Modification systems, including GATC of the DNA adenine methylase (Dam), which methylates N6-methyladenine (m6A) across all our K. pneumoniae assemblies. There was a consistent lack of methylation by Dam of the GATC motif downstream of two genes: fosA, a locus associated with low level fosfomycin resistance, and tnpB transposase on IncFIB(K) plasmids. Overall, we have constructed eight high quality reference genomes of K. pneumoniae, with insights into horizontal gene transfer and methylation m6A motifs.
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Affiliation(s)
- Anton Spadar
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - João Perdigão
- Research Institute for Medicines (iMed.ULisboa), Faculdade de Farmácia, Universidade de Lisboa, Lisboa, Portugal
| | - Jody Phelan
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - James Charleston
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Ana Modesto
- Research Institute for Medicines (iMed.ULisboa), Faculdade de Farmácia, Universidade de Lisboa, Lisboa, Portugal
| | - Rita Elias
- Research Institute for Medicines (iMed.ULisboa), Faculdade de Farmácia, Universidade de Lisboa, Lisboa, Portugal
| | | | - Martin L Hibberd
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Susana Campino
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Aida Duarte
- Faculdade de Farmácia, Universidade de Lisboa, Lisboa, Portugal
- Centro de Investigação Interdisciplinar Egas Moniz, Instituto Universitário Egas Moniz, Almada, Portugal
| | - Taane G Clark
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK.
- Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK.
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.
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