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Kadkhoda H, Gholizadeh P, Ghotaslou R, Pirzadeh T, Ahangarzadeh Rezaee M, Nabizadeh E, Feizi H, Samadi Kafil H, Aghazadeh M. Prevalence of the CRISPR-cas system and its association with antibiotic resistance in clinical Klebsiella pneumoniae isolates. BMC Infect Dis 2024; 24:554. [PMID: 38831286 PMCID: PMC11149351 DOI: 10.1186/s12879-024-09451-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2024] [Accepted: 05/30/2024] [Indexed: 06/05/2024] Open
Abstract
BACKGROUND AND OBJECTIVE(S) CRISPR-Cas is a prokaryotic adaptive immune system that protects bacteria and archaea against mobile genetic elements (MGEs) such as bacteriophages plasmids, and transposons. In this study, we aimed to assess the prevalence of the CRISPR-Cas systems and their association with antibiotic resistance in one of the most challenging bacterial pathogens, Klebsiella pneumoniae. MATERIALS AND METHODS A total of 105 K. pneumoniae isolates were collected from various clinical infections. Extended-spectrum β-lactamases (ESBLs) phenotypically were detected and the presence of ESBL, aminoglycoside-modifying enzymes (AME), and CRISPR-Cas system subtype genes were identified using PCR. Moreover, the diversity of the isolates was determined by enterobacterial repetitive intergenic consensus (ERIC)-PCR. RESULTS Phenotypically, 41.9% (44/105) of the isolates were found to be ESBL producers. A significant inverse correlation existed between the subtype I-E CRISPR-Cas system's presence and ESBL production in K. pneumoniae isolates. Additionally, the frequency of the ESBL genes blaCTX-M1 (3%), blaCTX-M9 (12.1%), blaSHV (51.5%), and blaTEM (33.3%), as well as some AME genes such as aac(3)-Iva (21.2%) and ant(2'')-Ia (3%) was significantly lower in the isolates with the subtype I-E CRISPR-Cas system in comparison to CRISPR-negative isolates. There was a significant inverse correlation between the presence of ESBL and some AME genes with subtype I-E CRISPR-Cas system. CONCLUSION The presence of the subtype I-E CRISPR-Cas system was correlated with the antibiotic-resistant gene (ARGs). The isolates with subtype I-E CRISPR-Cas system had a lower frequency of ESBL genes and some AME genes than CRISPR-negative isolates.
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Affiliation(s)
- Hiva Kadkhoda
- Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
- Department of Medical Microbiology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Pourya Gholizadeh
- Digestive Disease Research Center, Ardabil University of Medical Sciences, Ardabil, Iran
- Zoonoses Research Center, Ardabil University of Medical Sciences, Ardabil, Iran
| | - Reza Ghotaslou
- Department of Medical Microbiology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
- Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Tahereh Pirzadeh
- Department of Medical Microbiology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
- Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | - Edris Nabizadeh
- Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
- Department of Medical Microbiology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hadi Feizi
- Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
- Department of Medical Microbiology, Aalinasab Hospital, Social Security Organization, Tabriz, Iran
| | - Hossein Samadi Kafil
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
| | - Mohammad Aghazadeh
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
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Beck C, Krusche J, Elsherbini AMA, Du X, Peschel A. Phage susceptibility determinants of the opportunistic pathogen Staphylococcus epidermidis. Curr Opin Microbiol 2024; 78:102434. [PMID: 38364502 DOI: 10.1016/j.mib.2024.102434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 01/16/2024] [Accepted: 01/18/2024] [Indexed: 02/18/2024]
Abstract
Staphylococcus epidermidis is a common member of the human skin and nose microbiomes and a frequent cause of invasive infections. Transducing phages accomplish the horizontal transfer of resistance and virulence genes by mispackaging of mobile-genetic elements, contributing to severe, therapy-refractory S. epidermidis infections. Lytic phages on the other hand can be interesting candidates for new anti-S. epidermidis phage therapies. Despite the importance of phages, we are only beginning to unravel S. epidermidis phage interactions. Recent studies shed new light on S. epidermidis phage diversity, host range, and receptor specificities. Modulation of cell wall teichoic acids, the major phage receptor structures, along with other phage defense mechanisms, are crucial determinants for S. epidermidis susceptibility to different phage groups.
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Affiliation(s)
- Christian Beck
- Cluster of Excellence "Controlling Microbes to Fight Infections (CMFI)", University of Tübingen, 72076 Tübingen, Germany; Interfaculty Institute of Microbiology and Infection Medicine Tübingen, Infection Biology, University of Tübingen, 72076 Tübingen, Germany; German Centre for Infection Research (DZIF), Partner Site Tübingen, 72076 Tübingen, Germany
| | - Janes Krusche
- Cluster of Excellence "Controlling Microbes to Fight Infections (CMFI)", University of Tübingen, 72076 Tübingen, Germany; Interfaculty Institute of Microbiology and Infection Medicine Tübingen, Infection Biology, University of Tübingen, 72076 Tübingen, Germany; German Centre for Infection Research (DZIF), Partner Site Tübingen, 72076 Tübingen, Germany
| | - Ahmed M A Elsherbini
- Cluster of Excellence "Controlling Microbes to Fight Infections (CMFI)", University of Tübingen, 72076 Tübingen, Germany; Interfaculty Institute of Microbiology and Infection Medicine Tübingen, Infection Biology, University of Tübingen, 72076 Tübingen, Germany; German Centre for Infection Research (DZIF), Partner Site Tübingen, 72076 Tübingen, Germany
| | - Xin Du
- Cluster of Excellence "Controlling Microbes to Fight Infections (CMFI)", University of Tübingen, 72076 Tübingen, Germany; Interfaculty Institute of Microbiology and Infection Medicine Tübingen, Infection Biology, University of Tübingen, 72076 Tübingen, Germany; German Centre for Infection Research (DZIF), Partner Site Tübingen, 72076 Tübingen, Germany
| | - Andreas Peschel
- Cluster of Excellence "Controlling Microbes to Fight Infections (CMFI)", University of Tübingen, 72076 Tübingen, Germany; Interfaculty Institute of Microbiology and Infection Medicine Tübingen, Infection Biology, University of Tübingen, 72076 Tübingen, Germany; German Centre for Infection Research (DZIF), Partner Site Tübingen, 72076 Tübingen, Germany.
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3
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Shabbir MAB, Ul-Rahman A, Iftikhar MR, Rasheed M, Maan MK, Sattar A, Ahmad M, Khan FA, Ahmad W, Riaz MI, Aslam HB. Exploring the Interplay of the CRISPR-CAS System with Antibiotic Resistance in Staphylococcus aureus: A Poultry Meat Study from Lahore, Pakistan. MEDICINA (KAUNAS, LITHUANIA) 2024; 60:130. [PMID: 38256391 PMCID: PMC10818619 DOI: 10.3390/medicina60010130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 01/02/2024] [Accepted: 01/08/2024] [Indexed: 01/24/2024]
Abstract
Staphylococcus aureus is one of the major pathogens responsible for causing food poisoning worldwide. The emergence of antibiotic resistance in this bacterium is influenced by various factors. Among them, bacterial acquired defense systems described as clustered regularly interspaced short palindromic repeats (CRISPR)-cas system might be involved in antibiotic resistance development in bacteria. The current study was designed to assess the prevalence of S. aureus and its antibiotic resistance profile and identify the relationship of the CRISPR-cas system with antimicrobial resistance, followed by phylogenetic analysis. Total samples (n = 188) of poultry meat were collected from the poultry bird market of Lahore, Punjab, Pakistan. We used both phenotypic (antibiotic disc diffusion) and genotypic methods (PCR) to identify multi-drug resistant (MDR) strains of S. aureus. Additionally, the role of the CRISPR-Cas system in the isolated MDR S. aureus was also assessed. In addition, real-time quantitative PCR (qRT-PCR) was used to evaluate the association of the CRISPR-cas system with antimicrobial resistance. All of the S. aureus isolates showed 100% resistance against erythromycin, 97.5% were resistant to tetracycline, and 75% were resistant to methicillin. Eleven isolates were MDR in the current study. The CRISPR system was found in all MDR isolates, and fifteen spacers were identified within the CRISPR locus. Furthermore, MDR S. aureus isolates and the standard strain showed higher expression levels of CRISPR-associated genes. The correlation of said system with MDR isolates points to foreign gene acquisition by horizontal transfer. Current knowledge could be utilized to tackle antibiotic-resistant bacteria, mainly S. aureus.
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Affiliation(s)
- Muhammad Abu Bakr Shabbir
- Institute of Microbiology, Faculty of Veterinary Sciences, University of Veterinary and Animal Sciences, Lahore 54000, Pakistan (F.A.K.)
| | - Aziz Ul-Rahman
- Department of Pathobiology and Biomedical Sciences, Faculty of Veterinary and Animal Sciences, Muhammad Nawaz Shareef (MNS) University of Agriculture, Multan 66000, Pakistan;
| | - Muhammad Rizwan Iftikhar
- Institute of Microbiology, Faculty of Veterinary Sciences, University of Veterinary and Animal Sciences, Lahore 54000, Pakistan (F.A.K.)
| | - Majeeda Rasheed
- Department of life Sciences, Khwaja Fareed University of Engineering and Information Technology, Rahim Yar Khan 64200, Pakistan;
| | - Muhammad Kashif Maan
- Department of Veterinary Surgery, Faculty of Veterinary Sciences, University of Veterinary and Animal Sciences, Lahore 54000, Pakistan
| | - Adeel Sattar
- Department of Pharmacology and Toxicology, Faculty of Biosciences, University of Veterinary and Animal Sciences, Lahore 54000, Pakistan
| | - Mehmood Ahmad
- Department of Pharmacology and Toxicology, Faculty of Veterinary and Animal Sciences, The Islamia University of Bahawalpur, Bahawalpur 63100, Pakistan;
| | - Farid Ahmed Khan
- Institute of Microbiology, Faculty of Veterinary Sciences, University of Veterinary and Animal Sciences, Lahore 54000, Pakistan (F.A.K.)
| | - Waqas Ahmad
- Department of Pathology, Faculty of Veterinary Sciences, University of Veterinary and Animal Sciences, Lahore 54000, Pakistan;
| | - Muhammad Ilyas Riaz
- Institute of Microbiology, Faculty of Veterinary Sciences, University of Veterinary and Animal Sciences, Lahore 54000, Pakistan (F.A.K.)
| | - Hassaan Bin Aslam
- Institute of Microbiology, Faculty of Veterinary Sciences, University of Veterinary and Animal Sciences, Lahore 54000, Pakistan (F.A.K.)
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Mikkelsen K, Bowring JZ, Ng YK, Svanberg Frisinger F, Maglegaard JK, Li Q, Sieber RN, Petersen A, Andersen PS, Rostøl JT, Høyland-Kroghsbo NM, Ingmer H. An Endogenous Staphylococcus aureus CRISPR-Cas System Limits Phage Proliferation and Is Efficiently Excised from the Genome as Part of the SCC mec Cassette. Microbiol Spectr 2023; 11:e0127723. [PMID: 37404143 PMCID: PMC10434264 DOI: 10.1128/spectrum.01277-23] [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: 03/28/2023] [Accepted: 06/11/2023] [Indexed: 07/06/2023] Open
Abstract
CRISPR-Cas is an adaptive immune system that allows bacteria to inactivate mobile genetic elements. Approximately 50% of bacteria harbor CRISPR-Cas; however, in the human pathogen Staphylococcus aureus, CRISPR-Cas loci are less common and often studied in heterologous systems. We analyzed the prevalence of CRISPR-Cas in genomes of methicillin-resistant Staphylococcus aureus (MRSA) strains isolated in Denmark. Only 2.9% of the strains carried CRISPR-Cas systems, but for strains of sequence type ST630, over half were positive. All CRISPR-Cas loci were type III-A and located within the staphylococcal cassette chromosome mec (SCCmec) type V(5C2&5), conferring β-lactam resistance. Curiously, only 23 different CRISPR spacers were identified in 69 CRISPR-Cas positive strains, and almost identical SCCmec cassettes, CRISPR arrays, and cas genes are present in staphylococcal species other than S. aureus, suggesting that these were transferred horizontally. For the ST630 strain 110900, we demonstrate that the SCCmec cassette containing CRISPR-Cas is excised from the chromosome at high frequency. However, the cassette was not transferable under the conditions investigated. One of the CRISPR spacers targets a late gene in the lytic bacteriophage phiIPLA-RODI, and we show that the system protects against phage infection by reducing phage burst size. However, CRISPR-Cas can be overloaded or circumvented by CRISPR escape mutants. Our results imply that the endogenous type III-A CRISPR-Cas system in S. aureus is active against targeted phages, albeit with low efficacy. This suggests that native S. aureus CRISPR-Cas offers only partial immunity and in nature may work in tandem with other defense systems. IMPORTANCE CRISPR-Cas is an adaptive immune system protecting bacteria and archaea against mobile genetic elements such as phages. In strains of Staphylococcus aureus, CRISPR-Cas is rare, but when present, it is located within the SCCmec element, which encodes resistance to methicillin and other β-lactam antibiotics. We show that the element is excisable, suggesting that the CRISPR-Cas locus is transferable. In support of this, we found almost identical CRISPR-Cas-carrying SCCmec elements in different species of non-S. aureus staphylococci, indicating that the system is mobile but only rarely acquires new spacers in S. aureus. Additionally, we show that in its endogenous form, the S. aureus CRISPR-Cas is active but inefficient against lytic phages that can overload the system or form escape mutants. Thus, we propose that CRISPR-Cas in S. aureus offers only partial immunity in native systems and so may work with other defense systems to prevent phage-mediated killing.
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Affiliation(s)
- Kasper Mikkelsen
- Department of Veterinary and Animal Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Janine Zara Bowring
- Department of Veterinary and Animal Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Yong Kai Ng
- Department of Veterinary and Animal Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Bacteria, Parasites and Fungi, Statens Serum Institut, Copenhagen, Denmark
| | | | | | - Qiuchun Li
- Jiangsu Key Lab of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, China
| | - Raphael N. Sieber
- Department of Bacteria, Parasites and Fungi, Statens Serum Institut, Copenhagen, Denmark
| | - Andreas Petersen
- Department of Bacteria, Parasites and Fungi, Statens Serum Institut, Copenhagen, Denmark
| | - Paal Skytt Andersen
- Department of Veterinary and Animal Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Bacteria, Parasites and Fungi, Statens Serum Institut, Copenhagen, Denmark
| | - Jakob T. Rostøl
- Centre for Bacterial Resistance Biology, Imperial College London, London, United Kingdom
| | - Nina Molin Høyland-Kroghsbo
- Department of Veterinary and Animal Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Hanne Ingmer
- Department of Veterinary and Animal Sciences, University of Copenhagen, Copenhagen, Denmark
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5
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Walsh SK, Imrie RM, Matuszewska M, Paterson GK, Weinert LA, Hadfield JD, Buckling A, Longdon B. The host phylogeny determines viral infectivity and replication across Staphylococcus host species. PLoS Pathog 2023; 19:e1011433. [PMID: 37289828 PMCID: PMC10284401 DOI: 10.1371/journal.ppat.1011433] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 06/21/2023] [Accepted: 05/18/2023] [Indexed: 06/10/2023] Open
Abstract
Virus host shifts, where a virus transmits to and infects a novel host species, are a major source of emerging infectious disease. Genetic similarity between eukaryotic host species has been shown to be an important determinant of the outcome of virus host shifts, but it is unclear if this is the case for prokaryotes where anti-virus defences can be transmitted by horizontal gene transfer and evolve rapidly. Here, we measure the susceptibility of 64 strains of Staphylococcaceae bacteria (48 strains of Staphylococcus aureus and 16 non-S. aureus species spanning 2 genera) to the bacteriophage ISP, which is currently under investigation for use in phage therapy. Using three methods-plaque assays, optical density (OD) assays, and quantitative (q)PCR-we find that the host phylogeny explains a large proportion of the variation in susceptibility to ISP across the host panel. These patterns were consistent in models of only S. aureus strains and models with a single representative from each Staphylococcaceae species, suggesting that these phylogenetic effects are conserved both within and among host species. We find positive correlations between susceptibility assessed using OD and qPCR and variable correlations between plaque assays and either OD or qPCR, suggesting that plaque assays alone may be inadequate to assess host range. Furthermore, we demonstrate that the phylogenetic relationships between bacterial hosts can generally be used to predict the susceptibility of bacterial strains to phage infection when the susceptibility of closely related hosts is known, although this approach produced large prediction errors in multiple strains where phylogeny was uninformative. Together, our results demonstrate the ability of bacterial host evolutionary relatedness to explain differences in susceptibility to phage infection, with implications for the development of ISP both as a phage therapy treatment and as an experimental system for the study of virus host shifts.
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Affiliation(s)
- Sarah K. Walsh
- Centre for Ecology and Conservation; Faculty of Environment, Science, and Economy; Biosciences; University of Exeter; Cornwall; United Kingdom
- Environment and Sustainability Institute; University of Exeter; Cornwall; United Kingdom
| | - Ryan M. Imrie
- Centre for Ecology and Conservation; Faculty of Environment, Science, and Economy; Biosciences; University of Exeter; Cornwall; United Kingdom
| | - Marta Matuszewska
- Department of Medicine; University of Cambridge; Cambridge; United Kingdom
| | - Gavin K. Paterson
- Royal (Dick) School of Veterinary Studies and the Roslin Institute; University of Edinburgh;Edinburgh; United Kingdom
| | - Lucy A. Weinert
- Department of Veterinary Medicine; University of Cambridge; Cambridge; United Kingdom
| | - Jarrod D. Hadfield
- Institute of Evolutionary Biology; The University of Edinburgh; Edinburgh; United Kingdom
| | - Angus Buckling
- Centre for Ecology and Conservation; Faculty of Environment, Science, and Economy; Biosciences; University of Exeter; Cornwall; United Kingdom
- Environment and Sustainability Institute; University of Exeter; Cornwall; United Kingdom
| | - Ben Longdon
- Centre for Ecology and Conservation; Faculty of Environment, Science, and Economy; Biosciences; University of Exeter; Cornwall; United Kingdom
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6
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Tao S, Zhou D, Chen H, Li N, Zheng L, Fang Y, Xu Y, Jiang Q, Liang W. Analysis of genetic structure and function of clustered regularly interspaced short palindromic repeats loci in 110 Enterococcus strains. Front Microbiol 2023; 14:1177841. [PMID: 37168121 PMCID: PMC10165109 DOI: 10.3389/fmicb.2023.1177841] [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: 03/02/2023] [Accepted: 04/05/2023] [Indexed: 05/13/2023] Open
Abstract
Clustered regularly interspaced short palindromic repeats (CRISPR) and their CRISPR-associated proteins (Cas) are an adaptive immune system involved in specific defenses against the invasion of foreign mobile genetic elements, such as plasmids and phages. This study aims to analyze the gene structure and to explore the function of the CRISPR system in the Enterococcus genome, especially with regard to drug resistance. The whole genome information of 110 enterococci was downloaded from the NCBI database to analyze the distribution and the structure of the CRISPR-Cas system including the Cas gene, repeat sequences, and spacer sequence of the CRISPR-Cas system by bioinformatics methods, and to find drug resistance-related genes and analyze the relationship between them and the CRISPR-Cas system. Multilocus sequence typing (MLST) of enterococci was performed against the reference MLST database. Information on the drug resistance of Enterococcus was retrieved from the CARD database, and its relationship to the presence or absence of CRISPR was statistically analyzed. Among the 110 Enterococcus strains, 39 strains (35.45%) contained a complete CRISPR-Cas system, 87 CRISPR arrays were identified, and 62 strains contained Cas gene clusters. The CRISPR system in the Enterococcus genome was mainly type II-A (59.68%), followed by type II-C (33.87%). The phylogenetic analysis of the cas1 gene sequence was basically consistent with the typing of the CRISPR-Cas system. Of the 74 strains included in the study for MLST typing, only 19 (25.68%) were related to CRISPR-Cas typing, while the majority of the strains (74.32%) of MLST typing were associated with the untyped CRISPR system. Additionally, the CRISPR-Cas system may only be related to the carrying rate of some drug-resistant genes and the drug-resistant phenotype. In conclusion, the distribution of the enterococcus CRISPR-Cas system varies greatly among different species and the presence of CRISPR loci reduces the horizontal transfer of some drug resistance genes.
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Affiliation(s)
- Shuan Tao
- School of Medicine, Jiangsu University, Zhenjiang, China
- Department of Clinical Laboratory, Ningbo First Hospital, Ningbo, China
| | - Dongdong Zhou
- Department of General Medicine, Ningbo First Hospital, Ningbo, China
| | - Huimin Chen
- School of Medicine, Jiangsu University, Zhenjiang, China
| | - Na Li
- Bengbu Medical College, Bengbu, China
| | - Lin Zheng
- Department of Clinical Laboratory, Ningbo First Hospital, Ningbo, China
| | - Yewei Fang
- Department of Clinical Laboratory, Ningbo First Hospital, Ningbo, China
| | - Yao Xu
- School of Medicine, Ningbo University, Ningbo, China
| | - Qi Jiang
- Department of Gastroenterology, Ningbo First Hospital, Ningbo, China
- *Correspondence: Qi Jiang,
| | - Wei Liang
- Department of Clinical Laboratory, Ningbo First Hospital, Ningbo, China
- Wei Liang,
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CRISPR in Modulating Antibiotic Resistance of ESKAPE Pathogens. Mol Biotechnol 2023; 65:1-16. [PMID: 35939207 DOI: 10.1007/s12033-022-00543-8] [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: 12/24/2021] [Accepted: 07/13/2022] [Indexed: 01/11/2023]
Abstract
The ESKAPE (Enterococcus spp., Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.) isolates both from the clinical settings and food products are demonstrated to gain resistance to multiple antimicrobials. Therefore, the ESKAPE pathogens pose a serious threat to public health, which warrants specific attention to developing alternative novel therapeutics. The clustered regularly interspaced short palindromic repeats associated (CRISPR-Cas) system is one of the novel methods for managing antibiotic-resistant strains. Specific Cas nucleases can be programmed against bacterial genomic sequences to decrease bacterial resistance to antibiotics. Moreover, a few CRISPR-Cas nucleases have the ability to the sequence-specific killing of bacterial strains. However, some pathogens acquire antibiotic resistance due to the presence of the CRISPR-Cas system. In brief, there is a wide range of functional diversity of CRISPR-Cas systems in bacterial pathogens. Hence, to be an effective and safe infection treatment strategy, a comprehensive understanding of the role of CRISPR-Cas systems in modulating antibiotic resistance in ESKAPE pathogens is essential. The present review summarizes all the mechanisms by which CRISPR confers and prevents antibiotic resistance in ESKAPE. The review also emphasizes the relationship between CRISPR-Cas systems, biofilm formation, and antibiotic resistance in ESKAPE.
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Understanding the Mechanisms That Drive Phage Resistance in Staphylococci to Prevent Phage Therapy Failure. Viruses 2022; 14:v14051061. [PMID: 35632803 PMCID: PMC9146914 DOI: 10.3390/v14051061] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 05/11/2022] [Accepted: 05/13/2022] [Indexed: 02/07/2023] Open
Abstract
Despite occurring at the microscopic scale, the armed race between phages and their bacterial hosts involves multiple mechanisms, some of which are just starting to be understood. On the one hand, bacteria have evolved strategies that can stop the viral infection at different stages (adsorption, DNA injection and replication, biosynthesis and assembly of the viral progeny and/or release of the newly formed virions); on the other, phages have gradually evolved counterattack strategies that allow them to continue infecting their prey. This co-evolutionary process has played a major role in the development of microbial populations in both natural and man-made environments. Notably, understanding the parameters of this microscopic war will be paramount to fully benefit from the application of phage therapy against dangerous, antibiotic-resistant human pathogens. This review gathers the current knowledge regarding the mechanisms of phage resistance in the Staphylococcus genus, which includes Staphylococcus aureus, one of the most concerning microorganisms in terms of antibiotic resistance acquisition. Some of these strategies involve permanent changes to the bacterial cell via mutations, while others are transient, adaptive changes whose expression depends on certain environmental cues or the growth phase. Finally, we discuss the most plausible strategies to limit the impact of phage resistance on therapy, with a special emphasis on the importance of a rational design of phage cocktails in order to thwart therapeutic failure.
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9
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Chitra MA, Varughese HS. Analysis of CRISPR-Cas system and antimicrobial resistance in Staphylococcus coagulans isolates. Lett Appl Microbiol 2022; 75:126-134. [PMID: 35366350 DOI: 10.1111/lam.13713] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 03/05/2022] [Accepted: 03/30/2022] [Indexed: 12/01/2022]
Abstract
CRISPR-Cas system contributes adaptive immunity to protect the bacterial and archaeal genome against invading mobile genetic elements. In this study, an attempt was made to characterize the CRISPR-Cas system in S. coagulans, the second most prevalent coagulase positive staphylococci causing skin infections in dogs. Out of 45 S. coagulans isolates, 42/45 (93.33%) strains contained CRISPR-Cas system and 45 confirmed CRISPR system was identified in 42 S. coagulans isolates. The length of CRISPR loci ranged from 167 bp to 2477 bp, and the number of spacers in each CRISPR was varied from two spacers to as high as 37 numbers. Direct repeat (DR) sequences were between 30 and 37, but most (35/45) of the direct repeats contained 36 sequences. The predominant S. coagulans strains 29/45 did not possess any antimicrobial resistant genes (ARG); 26/29 strains contained Type IIC CRISPR-Cas system. Three isolates from Antarctica seals neither contain CRISPR-Cas system nor ARG. Only 15/45 S. coagulans strains (33.33%) harboured at least one ARG and 13/15 of them were having mecA gene. All the methicillin susceptible S. coagulans isolates contained Type IIC CRISPR-Cas system. In contrast, many (10/13) S. coagulans isolates which were methicillin resistant had Type IIIA CRISPR-Cas system, and this Type IIIA CRISPR-Cas system was present within the SCCmec mobile genetic element. Hence, this study suggests that Type II CRISPR-Cas in S. coagulans isolates might have played a possible role in preventing acquisition of plasmid/ phage invasion and Type IIIA CRISPR-Cas system may have an insignificant role in the prevention of horizontal gene transfer of antimicrobial resistance genes in S. coagulans species.
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Affiliation(s)
- M Ananda Chitra
- Department of Veterinary Microbiology, Madras Veterinary College, Tamil Nadu Veterinary and Animal Sciences University, Chennai, 600007
| | - Hridya Susan Varughese
- Department of Veterinary Microbiology, Madras Veterinary College, Tamil Nadu Veterinary and Animal Sciences University, Chennai, 600007
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10
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Correlation between type IIIA CRISPR-Cas system and SCCmec in Staphylococcus epidermidis. Arch Microbiol 2021; 203:6275-6286. [PMID: 34668031 DOI: 10.1007/s00203-021-02595-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 09/21/2021] [Accepted: 09/22/2021] [Indexed: 12/25/2022]
Abstract
A subculture of S.epidermidis strain ATCC35984 that is amenable to genetically manipulate was occasionally found in our laboratory. This mutant exhibited susceptibility to methicillin in contrast to its parent strain. To unveil the underlying mechanism, whole-genome sequencing of the mutant was performed. A comparative analysis revealed that a large DNA fragment encompassing the CRISPR-Cas system, type I R-M system and the SCCmec element was deleted from the mutant. The large chromosomal deletion associated with CRISPR-Cas system was also observed to occur spontaneously in S. epidermidis in another independent laboratory, or artificially induced by introducing engineering crRNAs in other bacterial species. These findings imply the CRISPR-Cas systems can affect bacterial genome remodeling through deletion of the integrated MGEs (mobile genetic elements). Further bioinformatics analysis identified a higher carriage rate of SCCmec element in the S. epidermidis strains harboring the CRISPR-Cas system. MLST typing and phylogenetic analysis of those CRIPSR-Cas-positive S. epidermidis strains revealed multiple origins. In addition, distinct types of SCCmec carried in those strains suggested that acquisition of this MGE originated from multiple independent recombination events. Intriguingly, CRISPR-Cas systems are found to be always located in the vicinity of orfX gene among staphylococci. Allelic analysis of CRISPR loci flanking cas genes disclosed that the loci distal to the orfX gene are considerably stable and conserved, which probably serve as recombination hotspot between CRISPR-Cas system and phage or plasmid. Therefore, the findings generally support the notion that incomplete immune protection of CRISPR-Cas system can promote dissemination of its neighboring SCCmec element.
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Li Y, Mikkelsen K, Lluch I Grané O, Wang Z, Tang Y, Jiao X, Ingmer H, Høyland-Kroghsbo NM, Li Q. Functional Characterization of Type III-A CRISPR-Cas in a Clinical Human Methicillin-R Staphylococcus aureus Strain. CRISPR J 2021; 4:686-698. [PMID: 34558981 DOI: 10.1089/crispr.2021.0046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
CRISPR with its cas genes is an adaptive immune system that protects prokaryotes against foreign genetic elements. The type III-A CRISPR-Cas system is rarely found in Staphylococcus aureus, and little is known about its function in S. aureus. Here, we describe the genome characteristics of the clinical methicillin-resistant S. aureus (MRSA) strain TZ0912, carrying a type III-A CRISPR-Cas system. Phylogenetic analysis of 35 reported CRISPR-Cas-positive S. aureus strains revealed that the CRISPR-Cas system is prevalent in CC8 clones (10/35) and is located in the staphylococcal cassette chromosome mec (SCCmec) V, which confers methicillin resistance. Plasmid transformation and phage infection assays reveal that the type III-A CRISPR-Cas system protects TZ0912 against foreign DNA with sequence homology to the spacers located in the CRISPR array. We observed that the CRISPR-Cas immune system could effectively protect MRSA against phage attacks in both liquid culture and solid medium. In accordance with previous reports, using RNA-seq analysis and plasmid transformation assays, we find that the crRNAs close to the leading sequence of the CRISPR array are more highly expressed and are more effective at directing plasmid elimination compared to the distant spacers. This study established a model for evaluating the efficiency of naive CRISPR-Cas system in MRSA against phage, which could contribute to future research on the function of CRISPR-Cas in clinical MRSA isolates and improve phage therapy against MRSA infections.
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Affiliation(s)
- Yang Li
- Jiangsu Key Lab of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, P.R. China; University of Copenhagen, Copenhagen, Denmark.,Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agri-food Safety and Quality, Ministry of Agriculture of China, Yangzhou University, P.R. China; University of Copenhagen, Copenhagen, Denmark
| | - Kasper Mikkelsen
- Department of Veterinary and Animal Sciences, University of Copenhagen, Copenhagen, Denmark; University of Copenhagen, Copenhagen, Denmark
| | - Oleguer Lluch I Grané
- Department of Veterinary and Animal Sciences, University of Copenhagen, Copenhagen, Denmark; University of Copenhagen, Copenhagen, Denmark
| | - Zhenyu Wang
- Jiangsu Key Lab of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, P.R. China; University of Copenhagen, Copenhagen, Denmark.,Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agri-food Safety and Quality, Ministry of Agriculture of China, Yangzhou University, P.R. China; University of Copenhagen, Copenhagen, Denmark
| | - Yuanyue Tang
- Jiangsu Key Lab of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, P.R. China; University of Copenhagen, Copenhagen, Denmark.,Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agri-food Safety and Quality, Ministry of Agriculture of China, Yangzhou University, P.R. China; University of Copenhagen, Copenhagen, Denmark.,Joint International Research Laboratory of Agriculture and Agri-Product Safety, Yangzhou University, P.R. China; and University of Copenhagen, Copenhagen, Denmark
| | - Xinan Jiao
- Jiangsu Key Lab of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, P.R. China; University of Copenhagen, Copenhagen, Denmark.,Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agri-food Safety and Quality, Ministry of Agriculture of China, Yangzhou University, P.R. China; University of Copenhagen, Copenhagen, Denmark.,Joint International Research Laboratory of Agriculture and Agri-Product Safety, Yangzhou University, P.R. China; and University of Copenhagen, Copenhagen, Denmark
| | - Hanne Ingmer
- Department of Veterinary and Animal Sciences, University of Copenhagen, Copenhagen, Denmark; University of Copenhagen, Copenhagen, Denmark
| | | | - Qiuchun Li
- Jiangsu Key Lab of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, P.R. China; University of Copenhagen, Copenhagen, Denmark.,Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agri-food Safety and Quality, Ministry of Agriculture of China, Yangzhou University, P.R. China; University of Copenhagen, Copenhagen, Denmark.,Joint International Research Laboratory of Agriculture and Agri-Product Safety, Yangzhou University, P.R. China; and University of Copenhagen, Copenhagen, Denmark
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12
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Maguvu TE, Oladipo AO, Bezuidenhout CC. Analysis of Genome Sequences of Coagulase-Negative Staphylococci Isolates from South Africa and Nigeria Highlighted Environmentally Driven Heterogeneity. J Genomics 2021; 9:26-37. [PMID: 34025805 PMCID: PMC8133835 DOI: 10.7150/jgen.53019] [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: 09/08/2020] [Accepted: 10/28/2020] [Indexed: 11/27/2022] Open
Abstract
Here, we report high-quality annotated draft genomes of eight coagulase-negative staphylococci (CoNS) isolates obtained from South Africa and Nigeria. We explored the prevalence of antibiotic resistance and virulence genes, their association with mobile genetic elements. The pan-genomic analysis highlighted the environmentally driven heterogeneity of the isolates. Isolates from Nigeria had at least one gene for cadmium resistance/tolerance, these genes were not detected in isolates from South Africa. In contrast, isolates from South Africa had a tetM gene, which was not detected among the isolates from Nigeria. The observed genomic heterogeneity correlates with anthropogenic activities in the area where the isolates were collected. Moreover, the isolates used in this study possess an open pan-genome, which could easily explain the environmentally driven heterogeneity.
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Affiliation(s)
- Tawanda Elias Maguvu
- Unit for Environmental Sciences and Management: Microbiology, North-West University, Potchefstroom, South Africa. Private Bag X6001, Potchefstroom, 2520, South Africa
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13
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CRISPR-Cas systems in Proteus mirabilis. INFECTION GENETICS AND EVOLUTION 2021; 92:104881. [PMID: 33905883 DOI: 10.1016/j.meegid.2021.104881] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 02/14/2021] [Accepted: 04/19/2021] [Indexed: 12/19/2022]
Abstract
The Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) is a bacterial defense mechanism against bacteriophages composed of two different parts: the CRISPR array and the Cas genes. The spacer acquisition is done by the adaptation module consisting of the hallmark Cas1 Cas2 proteins, which inserts new spacers into the CRISPR array. Here we aimed to describe the CRISPR-Cas system in Proteus mirabilis (P. mirabilis) isolates. CRISPR loci was observed in 30 genomic contents of 109 P. mirabilis isolates that each locus was consisted of two CRISPR arrays and each array had a different preserved leader sequences. Only the type I-E CRISPR-Cas system was common in these isolates. The source of the spacers was identified, including phages and prophages. CRISPR spacer origin analysis also identified a conserved PAM sequence of 5'-AAG-3' nucleotide stretch. Through collecting spacers, CRISPR arrays of P. mirabilis isolates were expanded mostly by integration of bacteriophageal source of spacers. This study shows novel findings in the area of the P-mirabilis CRISPR-Cas system. In this regard, among analyzed genome of P. mirabilis isolates, Class I CRISR-Cas systems were dominant, and all belonged to type I-E. In the flanks of the CRISPR, some other elements with regulatory role were also found. A motif of 11 nt size was found to be preserved among the analyzed genome. We believe that it might has a CRISPR-Cas system transcription facilitator by targeting the Rho element.
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14
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Liao W, Liu Y, Chen C, Li J, Du F, Long D, Zhang W. Distribution of CRISPR-Cas Systems in Clinical Carbapenem-Resistant Klebsiella pneumoniae Strains in a Chinese Tertiary Hospital and Its Potential Relationship with Virulence. Microb Drug Resist 2020; 26:630-636. [PMID: 31834846 DOI: 10.1089/mdr.2019.0276] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Affiliation(s)
- Wenjian Liao
- Department of Respiratory Medicine, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Yang Liu
- Department of Clinical Microbiology, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Chuanhui Chen
- Department of Respiratory Medicine, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Jie Li
- Department of Internal Medicine, Jiangxi Provincial Chest Hospital, Nanchang, China
| | - Fangling Du
- Department of Clinical Microbiology, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Dan Long
- Department of Clinical Microbiology, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Wei Zhang
- Department of Respiratory Medicine, The First Affiliated Hospital of Nanchang University, Nanchang, China
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15
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Tang B, Gong T, Cui Y, Wang L, He C, Lu M, Chen J, Jing M, Zhang A, Li Y. Characteristics of oral methicillin-resistant Staphylococcus epidermidis isolated from dental plaque. Int J Oral Sci 2020; 12:15. [PMID: 32385260 PMCID: PMC7210960 DOI: 10.1038/s41368-020-0079-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 01/29/2020] [Accepted: 03/30/2020] [Indexed: 02/05/2023] Open
Abstract
The oral microbial community is widely regarded as a latent reservoir of antibiotic resistance genes. This study assessed the molecular epidemiology, susceptibility profile, and resistance mechanisms of 35 methicillin-resistant Staphylococcus epidermidis (MRSE) strains isolated from the dental plaque of a healthy human population. Broth microdilution minimum inhibitory concentrations (MICs) revealed that all the isolates were nonsusceptible to oxacillin and penicillin G. Most of them were also resistant to trimethoprim (65.7%) and erythromycin (54.3%). The resistance to multiple antibiotics was found to be largely due to the acquisition of plasmid-borne genes. The mecA and dfrA genes were found in all the isolates, mostly dfrG (80%), aacA-aphD (20%), aadD (28.6%), aphA3 (22.9%), msrA (5.7%), and the ermC gene (14.3%). Classical mutational mechanisms found in these isolates were mainly efflux pumps such as qacA (31.4%), qacC (25.7%), tetK (17.1%), and norA (8.6%). Multilocus sequence type analysis revealed that sequence type 59 (ST59) strains comprised 71.43% of the typed isolates, and the eBURST algorithm clustered STs into the clonal complex 2-II(CC2-II). The staphyloccoccal cassette chromosome mec (SCCmec) type results showed that 25 (71.43%) were assigned to type IV. Moreover, 88.66% of the isolates were found to harbor six or more biofilm-associated genes. The aap, atlE, embp, sdrF, and IS256 genes were detected in all 35 isolates. This research demonstrates that biofilm-positive multiple-antibiotic-resistant ST59-SCCmec IV S. epidermidis strains exist in the dental plaque of healthy people and may be a potential risk for the transmission of antibiotic resistance.
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Affiliation(s)
- Boyu Tang
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Tao Gong
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Yujia Cui
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Lingyun Wang
- Division of Infectious Diseases, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Chao He
- Department of Laboratory Medicine, West China Hospital, Sichuan University, Chengdu, China
| | - Miao Lu
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Jiamin Chen
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Meiling Jing
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Anqi Zhang
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Yuqing Li
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & West China Hospital of Stomatology, Sichuan University, Chengdu, China.
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16
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Brooks MR, Padilla-Vélez L, Khan TA, Qureshi AA, Pieper JB, Maddox CW, Alam MT. Prophage-Mediated Disruption of Genetic Competence in Staphylococcus pseudintermedius. mSystems 2020; 5:e00684-19. [PMID: 32071159 PMCID: PMC7029219 DOI: 10.1128/msystems.00684-19] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Accepted: 01/27/2020] [Indexed: 11/20/2022] Open
Abstract
Methicillin-resistant Staphylococcus pseudintermedius (MRSP) is a major cause of soft tissue infections in dogs and occasionally infects humans. Hypervirulent multidrug-resistant (MDR) MRSP clones have emerged globally. The sequence types ST71 and ST68, the major epidemic clones of Europe and North America, respectively, have spread to other regions. The genetic factors underlying the success of these clones have not been investigated thoroughly. Here, we performed a comprehensive genomic analysis of 371 S. pseudintermedius isolates to dissect the differences between major clonal lineages. We show that the prevalence of genes associated with antibiotic resistance, virulence, prophages, restriction-modification (RM), and CRISPR/Cas systems differs significantly among MRSP clones. The isolates with GyrA+GrlA mutations, conferring fluoroquinolone resistance, carry more of these genes than those without GyrA+GrlA mutations. ST71 and ST68 clones carry lineage-specific prophages with genes that are likely associated with their increased fitness and virulence. We have discovered that a prophage, SpST71A, is inserted within the comGA gene of the late competence operon comG in the ST71 lineage. A functional comG is essential for natural genetic competence, which is one of the major modes of horizontal gene transfer (HGT) in bacteria. The RM and CRISPR/Cas systems, both major genetic barriers to HGT, are also lineage specific. Clones harboring CRISPR/Cas or a prophage-disrupted comG exhibited less genetic diversity and lower rates of recombination than clones lacking these systems. After Listeria monocytogenes, this is the second example of prophage-mediated competence disruption reported in any bacteria. These findings are important for understanding the evolution and clonal expansion of MDR MRSP clones.IMPORTANCE Staphylococcus pseudintermedius is a bacterium responsible for clinically important infections in dogs and can infect humans. In this study, we performed genomic analysis of 371 S. pseudintermedius isolates to understand the evolution of antibiotic resistance and virulence in this organism. The analysis covered significant reported clones, including ST71 and ST68, the major epidemic clones of Europe and North America, respectively. We show that the prevalence of genes associated with antibiotic resistance, virulence, prophages, and horizontal gene transfer differs among clones. ST71 and ST68 carry prophages with novel virulence and antibiotic resistance genes. Importantly, site-specific integration of a prophage, SpST71A, has led to the disruption of the genetic competence operon comG in ST71 clone. A functional comG is essential for the natural uptake of foreign DNA and thus plays an important role in the evolution of bacteria. This study provides insight into the emergence and evolution of antibiotic resistance and virulence in S. pseudintermedius, which may help in efforts to combat this pathogen.
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Affiliation(s)
- Michael R Brooks
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Lyan Padilla-Vélez
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Tarannum A Khan
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Azaan A Qureshi
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Jason B Pieper
- Department of Veterinary Clinical Medicine, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Carol W Maddox
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Md Tauqeer Alam
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
- Department of Veterinary Clinical Medicine, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
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17
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Abstract
Bacteria in the genus Staphylococcus are important targets for phage therapy due to their prevalence as pathogens and increasing antibiotic resistance. Here we review Staphylococcus outer surface features and specific phage resistance mechanisms that define the host range, the set of strains that an individual phage can potentially infect. Phage infection goes through five distinct phases: attachment, uptake, biosynthesis, assembly, and lysis. Adsorption inhibition, encompassing outer surface teichoic acid receptor alteration, elimination, or occlusion, limits successful phage attachment and entry. Restriction-modification systems (in particular, type I and IV systems), which target phage DNA inside the cell, serve as the major barriers to biosynthesis as well as transduction and horizontal gene transfer between clonal complexes and species. Resistance to late stages of infection occurs through mechanisms such as assembly interference, in which staphylococcal pathogenicity islands siphon away superinfecting phage proteins to package their own DNA. While genes responsible for teichoic acid biosynthesis, capsule, and restriction-modification are found in most Staphylococcus strains, a variety of other host range determinants (e.g., clustered regularly interspaced short palindromic repeats, abortive infection, and superinfection immunity) are sporadic. The fitness costs of phage resistance through teichoic acid structure alteration could make staphylococcal phage therapies promising, but host range prediction is complex because of the large number of genes involved, and the roles of many of these are unknown. In addition, little is known about the genetic determinants that contribute to host range expansion in the phages themselves. Future research must identify host range determinants, characterize resistance development during infection and treatment, and examine population-wide genetic background effects on resistance selection.
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Affiliation(s)
- Abraham G Moller
- Program in Microbiology and Molecular Genetics (MMG), Graduate Division of Biological and Biomedical Sciences (GDBBS), Emory University School of Medicine, Atlanta, Georgia, USA
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Jodi A Lindsay
- Institute of Infection and Immunity, St. George's, University of London, London, United Kingdom
| | - Timothy D Read
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
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18
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Verma R, Sahu R, Singh DD, Egbo TE. A CRISPR/Cas9 based polymeric nanoparticles to treat/inhibit microbial infections. Semin Cell Dev Biol 2019; 96:44-52. [PMID: 30986568 DOI: 10.1016/j.semcdb.2019.04.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 04/11/2019] [Indexed: 12/17/2022]
Abstract
The latest breakthrough towards the adequate and decisive methods of gene editing tools provided by CRISPR/Cas9 (Clustered Regularly Interspaced Short Palindromic Repeat/CRISPR Associated System), has been repurposed into a tool for genetically engineering eukaryotic cells and now considered as the major innovation in gene-related disorders. Nanotechnology has provided an alternate way to overcome the conventional problems where methods to deliver therapeutic agents have failed. The use of nanotechnology has the potential to safe-side the CRISPR/Cas9 components delivery by using customized polymeric nanoparticles for safety and efficacy. The pairing of two (CRISPR/Cas9 and nanotechnology) has the potential for opening new avenues in therapeutic use. In this review, we will discuss the most recent advances in developing nanoparticle-based CRISPR/Cas9 gene editing cargo delivery with a focus on several polymeric nanoparticles including fabrication proposals to combat microbial infections.
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Affiliation(s)
- Richa Verma
- Center for Nanobiotechnology Research, Department of Biological Sciences, Alabama State University, Montgomery, AL, 36104, USA
| | - Rajnish Sahu
- Center for Nanobiotechnology Research, Department of Biological Sciences, Alabama State University, Montgomery, AL, 36104, USA
| | - Desh Deepak Singh
- Amity Institute of Biotechnology, Amity University, Jaipur, Rajasthan, 303002, India
| | - Timothy E Egbo
- Department of Biological Sciences, College of Science Technology Engineering and Mathematics, Alabama State University, Montgomery, AL, 36104, USA.
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19
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CRISPR tracking reveals global spreading of antimicrobial resistance genes by Staphylococcus of canine origin. Vet Microbiol 2019; 232:65-69. [PMID: 31030846 DOI: 10.1016/j.vetmic.2019.04.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 03/29/2019] [Accepted: 04/05/2019] [Indexed: 11/20/2022]
Abstract
The close contact between pets and their owners is a potential source for microorganisms and genetic material exchange. Staphylococcus species considered as harmless inhabitants of animals' and humans' microbiota can act as reservoirs of antimicrobial resistance genes to more virulent species, thereby increasing their potential to resist drug therapy. This process could be inhibited by the antiplasmid immunity conferred by CRISPR systems. On the other hand, CRISPR spacer sequences can be explored as molecular clocks to track the history of genetic invasion suffered by a bacterial strain. To understand better the role of domestic dogs in human health as an antimicrobial resistance genes source, we analyzed 129 genomes of Staphylococcus strains of canine origin for the presence of CRISPR systems. Only 8% of the strains were positive for CRISPR, which is consistent with Staphylococcus role as gene reservoirs. The plasmidial origin or some spacers confirms the unsuccessful attempt of plasmid exchange in strains carrying CRISPRs. Some of these systems are within a staphylococcal cassette chromosome mec (SCCmec), sharing 98% of identity between their harboring strains. These CRISPRs' spacers reveal that this SCCmec was transferred between canine S. pseudintermedius strains, then to S. schleiferi and to Staphylococcus strains isolated from human beings. Our findings shows genetic evidence for the global spreading of pathogenic bacteria and the antimicrobial resistance genes carried by them and reinforce that, in the age of antimicrobial resistance, it is imperative that drug therapies consider the integrated nature of the relationship between pets and humans.
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20
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Li Q, Li Y, Tang Y, Meng C, Ingmer H, Jiao X. Prevalence and characterization of Staphylococcus aureus and Staphylococcus argenteus in chicken from retail markets in China. Food Control 2019. [DOI: 10.1016/j.foodcont.2018.08.030] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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21
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Hidalgo-Cantabrana C, Sanozky-Dawes R, Barrangou R. Insights into the Human Virome Using CRISPR Spacers from Microbiomes. Viruses 2018; 10:v10090479. [PMID: 30205462 PMCID: PMC6165519 DOI: 10.3390/v10090479] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 08/31/2018] [Accepted: 09/03/2018] [Indexed: 12/21/2022] Open
Abstract
Due to recent advances in next-generation sequencing over the past decade, our understanding of the human microbiome and its relationship to health and disease has increased dramatically. Yet, our insights into the human virome, and its interplay with important microbes that impact human health, is relatively limited. Prokaryotic and eukaryotic viruses are present throughout the human body, comprising a large and diverse population which influences several niches and impacts our health at various body sites. The presence of prokaryotic viruses like phages, has been documented at many different body sites, with the human gut being the richest ecological niche. Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) and associated proteins constitute the adaptive immune system of bacteria, which prevents attack by invasive nucleic acid. CRISPR-Cas systems function by uptake and integration of foreign genetic element sequences into the CRISPR array, which constitutes a genomic archive of iterative vaccination events. Consequently, CRISPR spacers can be investigated to reconstruct interplay between viruses and bacteria, and metagenomic sequencing data can be exploited to provide insights into host-phage interactions within a niche. Here, we show how the CRISPR spacer content of commensal and pathogenic bacteria can be used to determine the evidence of their phage exposure. This framework opens new opportunities for investigating host-virus dynamics in metagenomic data, and highlights the need to dedicate more efforts for virome sampling and sequencing.
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Affiliation(s)
- Claudio Hidalgo-Cantabrana
- Department of Food, Bioprocessing and Nutrition Sciences, North Carolina State University, 400 Dan Allen Drive, Campus BOX 7624, Raleigh, NC 27695, USA.
| | - Rosemary Sanozky-Dawes
- Department of Food, Bioprocessing and Nutrition Sciences, North Carolina State University, 400 Dan Allen Drive, Campus BOX 7624, Raleigh, NC 27695, USA.
| | - Rodolphe Barrangou
- Department of Food, Bioprocessing and Nutrition Sciences, North Carolina State University, 400 Dan Allen Drive, Campus BOX 7624, Raleigh, NC 27695, USA.
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22
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Argemi X, Matelska D, Ginalski K, Riegel P, Hansmann Y, Bloom J, Pestel-Caron M, Dahyot S, Lebeurre J, Prévost G. Comparative genomic analysis of Staphylococcus lugdunensis shows a closed pan-genome and multiple barriers to horizontal gene transfer. BMC Genomics 2018; 19:621. [PMID: 30126366 PMCID: PMC6102843 DOI: 10.1186/s12864-018-4978-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 07/31/2018] [Indexed: 02/07/2023] Open
Abstract
Background Coagulase negative staphylococci (CoNS) are commensal bacteria on human skin. Staphylococcus lugdunensis is a unique CoNS which produces various virulence factors and may, like S. aureus, cause severe infections, particularly in hospital settings. Unlike other staphylococci, it remains highly susceptible to antimicrobials, and genome-based phylogenetic studies have evidenced a highly conserved genome that distinguishes it from all other staphylococci. Results We demonstrate that S. lugdunensis possesses a closed pan-genome with a very limited number of new genes, in contrast to other staphylococci that have an open pan-genome. Whole-genome nucleotide and amino acid identity levels are also higher than in other staphylococci. We identified numerous genetic barriers to horizontal gene transfer that might explain this result. The S. lugdunensis genome has multiple operons encoding for restriction-modification, CRISPR/Cas and toxin/antitoxin systems. We also identified a new PIN-like domain-associated protein that might belong to a larger operon, comprising a metalloprotease, that could function as a new toxin/antitoxin or detoxification system. Conclusion We show that S. lugdunensis has a unique genome profile within staphylococci, with a closed pan-genome and several systems to prevent horizontal gene transfer. Its virulence in clinical settings does not rely on its ability to acquire and exchange antibiotic resistance genes or other virulence factors as shown for other staphylococci. Electronic supplementary material The online version of this article (10.1186/s12864-018-4978-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Xavier Argemi
- Service des Maladies Infectieuses et Tropicales, Hôpitaux Universitaires, Nouvel Hôpital Civil, 1 Place de l'Hôpital, 67000, Strasbourg, France. .,Université de Strasbourg, CHRU Strasbourg, Fédération de Médecine Translationnelle de Strasbourg, EA 7290, Virulence Bactérienne Précoce, F-67000, Strasbourg, France.
| | - Dorota Matelska
- Laboratory of Bioinformatics and Systems Biology, Centre of New Technologies, University of Warsaw, Zwirki i Wigury 93, 02-089, Warsaw, Poland
| | - Krzysztof Ginalski
- Laboratory of Bioinformatics and Systems Biology, Centre of New Technologies, University of Warsaw, Zwirki i Wigury 93, 02-089, Warsaw, Poland
| | - Philippe Riegel
- Université de Strasbourg, CHRU Strasbourg, Fédération de Médecine Translationnelle de Strasbourg, EA 7290, Virulence Bactérienne Précoce, F-67000, Strasbourg, France
| | - Yves Hansmann
- Service des Maladies Infectieuses et Tropicales, Hôpitaux Universitaires, Nouvel Hôpital Civil, 1 Place de l'Hôpital, 67000, Strasbourg, France.,Université de Strasbourg, CHRU Strasbourg, Fédération de Médecine Translationnelle de Strasbourg, EA 7290, Virulence Bactérienne Précoce, F-67000, Strasbourg, France
| | - Jochen Bloom
- Bioinformatics & Systems Biology, Justus-Liebig-University Gießen, 35392, Gießen, Germany
| | - Martine Pestel-Caron
- Normandie Univ, UNIROUEN, GRAM EA2656, Rouen University Hospital, F-76000, Rouen, France
| | - Sandrine Dahyot
- Normandie Univ, UNIROUEN, GRAM EA2656, Rouen University Hospital, F-76000, Rouen, France
| | - Jérémie Lebeurre
- Normandie Univ, UNIROUEN, GRAM EA2656, Rouen University Hospital, F-76000, Rouen, France
| | - Gilles Prévost
- Université de Strasbourg, CHRU Strasbourg, Fédération de Médecine Translationnelle de Strasbourg, EA 7290, Virulence Bactérienne Précoce, F-67000, Strasbourg, France
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23
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Li Q, Wang X, Yin K, Hu Y, Xu H, Xie X, Xu L, Fei X, Chen X, Jiao X. Genetic analysis and CRISPR typing of Salmonella enterica serovar Enteritidis from different sources revealed potential transmission from poultry and pig to human. Int J Food Microbiol 2017; 266:119-125. [PMID: 29212058 DOI: 10.1016/j.ijfoodmicro.2017.11.025] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 10/21/2017] [Accepted: 11/26/2017] [Indexed: 10/18/2022]
Abstract
Salmonella enterica serovar Enteritidis (S. Enteritidis) is one of the most prevalent serotypes in Salmonella isolated from poultry and the most commonly reported cause of human salmonellosis. In this study, we aimed to assess the genetic diversity of 329 S. Enteritidis strains isolated from different sources from 2009 to 2016 in China. Clustered regularly interspaced short palindromic repeat (CRISPR) typing was used to characterize these 262 chicken clinical isolates, 38 human isolates, 18 pig isolates, six duck isolates, three goose isolates and two isolates of unknown source. A total of 18 Enteritidis CRISPR types (ECTs) were identified, with ECT2, ECT8 and ECT4 as the top three ECTs. CRISPR typing identified ECT2 as the most prevalent ECT, which accounted for 41% of S. Enteritidis strains from all the sources except duck. ECT9 and ECT13 were identified in both pig and human isolates and revealed potential transmission from pig to human. A cluster analysis distributed 18 ECTs, including the top three ECTs, into four lineages with LI as the predominant lineage. Forty-eight out of 329 isolates were subjected to whole genome sequence typing, which divided them into four clusters, with Cluster I as the predominant cluster. Cluster I included 92% (34/37) of strains located in LI identified from the CRISPR typing, confirming the good correspondence between both typing methods. In addition, the CRISPR typing also revealed the close relationship between ECTs and isolated areas, confirming that CRISPR spacers might be obtained by bacteria from the unique phage or plasmid pools in the environment. However, further analysis is needed to determine the function of CRISPR-Cas systems in Salmonella and the relationship between spacers and the environment.
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Affiliation(s)
- Qiuchun Li
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agri-food Safety and Quality, Ministry of Agriculture of China, Yangzhou University, China; Jiangsu Key Lab of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, China.
| | - Xin Wang
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agri-food Safety and Quality, Ministry of Agriculture of China, Yangzhou University, China; Jiangsu Key Lab of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, China
| | - Kequan Yin
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agri-food Safety and Quality, Ministry of Agriculture of China, Yangzhou University, China; Jiangsu Key Lab of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, China
| | - Yachen Hu
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agri-food Safety and Quality, Ministry of Agriculture of China, Yangzhou University, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety, Yangzhou University, China
| | - Haiyan Xu
- Nantong Center for Disease Control and Prevention, China
| | - Xiaolei Xie
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agri-food Safety and Quality, Ministry of Agriculture of China, Yangzhou University, China; Jiangsu Key Lab of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, China
| | - Lijuan Xu
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agri-food Safety and Quality, Ministry of Agriculture of China, Yangzhou University, China; Jiangsu Key Lab of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, China
| | - Xiao Fei
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agri-food Safety and Quality, Ministry of Agriculture of China, Yangzhou University, China; Jiangsu Key Lab of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, China
| | - Xiang Chen
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agri-food Safety and Quality, Ministry of Agriculture of China, Yangzhou University, China; Jiangsu Key Lab of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety, Yangzhou University, China
| | - Xinan Jiao
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agri-food Safety and Quality, Ministry of Agriculture of China, Yangzhou University, China; Jiangsu Key Lab of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety, Yangzhou University, China.
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24
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Abstract
Staphylococcus aureus is a serious human pathogen with remarkable adaptive powers. Antibiotic-resistant clones rapidly emerge mainly by acquisition of antibiotic-resistance genes from other S. aureus strains or even from other genera. Transfer is mediated by a diverse complement of mobile genetic elements and occurs primarily by conjugation or bacteriophage transduction, with the latter traditionally being perceived as the primary route. Recent work on conjugation and transduction suggests that transfer by these mechanisms may be more extensive than previously thought, in terms of the range of plasmids that can be transferred by conjugation and the efficiency with which transduction occurs. Here, we review the main routes of antibiotic resistance gene transfer in S. aureus in the context of its biology as a human commensal and a life-threatening pathogen.
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Affiliation(s)
- Jakob Haaber
- Department of Veterinary and Animal Sciences, Faculty of Health & Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - José R Penadés
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Hanne Ingmer
- Department of Veterinary and Animal Sciences, Faculty of Health & Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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25
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Walker FC, Hatoum-Aslan A. Conjugation Assay for Testing CRISPR-Cas Anti-plasmid Immunity in Staphylococci. Bio Protoc 2017; 7:e2293. [PMID: 28752109 DOI: 10.21769/bioprotoc.2293] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
CRISPR-Cas is a prokaryotic adaptive immune system that prevents uptake of mobile genetic elements such as bacteriophages and plasmids. Plasmid transfer between bacteria is of particular clinical concern due to increasing amounts of antibiotic resistant pathogens found in humans as a result of transfer of resistance plasmids within and between species. Testing the ability of CRISPR-Cas systems to block plasmid transfer in various conditions or with CRISPR-Cas mutants provides key insights into the functionality and mechanisms of CRISPR-Cas as well as how antibiotic resistance spreads within bacterial communities. Here, we describe a method for quantifying the impact of CRISPR-Cas on the efficiency of plasmid transfer by conjugation. While this method is presented in Staphylococcus species, it could be more broadly used for any conjugative prokaryote.
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Affiliation(s)
- Forrest C Walker
- Department of Biological Sciences, University of Alabama, Tuscaloosa, USA
| | - Asma Hatoum-Aslan
- Department of Biological Sciences, University of Alabama, Tuscaloosa, USA
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