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Díaz-Formoso L, Silva V, Contente D, Feito J, Hernández PE, Borrero J, Igrejas G, del Campo R, Muñoz-Atienza E, Poeta P, Cintas LM. Antibiotic Resistance Genes, Virulence Factors, and Biofilm Formation in Coagulase-Negative Staphylococcus spp. Isolates from European Hakes ( Merluccius merluccius, L.) Caught in the Northeast Atlantic Ocean. Pathogens 2023; 12:1447. [PMID: 38133330 PMCID: PMC10745931 DOI: 10.3390/pathogens12121447] [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: 11/05/2023] [Revised: 12/04/2023] [Accepted: 12/11/2023] [Indexed: 12/23/2023] Open
Abstract
The indiscriminate use of antibiotics has contributed to the dissemination of multiresistant bacteria, which represents a public health concern. The aim of this work was to characterize 27 coagulase-negative staphylococci (CoNS) isolated from eight wild Northeast Atlantic hakes (Merluccius merluccius, L.) and taxonomically identified as Staphylococcus epidermidis (n = 16), Staphylococcus saprophyticus (n = 4), Staphylococcus hominis (n = 3), Staphylococcus pasteuri (n = 2), Staphylococcus edaphicus (n = 1), and Staphylococcus capitis (n = 1). Biofilm formation was evaluated with a microtiter assay, antibiotic susceptibility testing was performed using the disk diffusion method, and antibiotic resistance and virulence determinants were detected by PCR. Our results showed that all staphylococci produced biofilms and that 92.6% of the isolates were resistant to at least one antibiotic, mainly penicillin (88.8%), fusidic acid (40.7%), and erythromycin (37%). The penicillin resistance gene (blaZ) was detected in 66.6% (18) of the isolates, of which 10 also carried resistance genes to macrolides and lincosamides (mphC, msr(A/B), lnuA, or vgaA), 4 to fusidic acid (fusB), and 3 to trimethoprim-sulfamethoxazole (dfrA). At least one virulence gene (scn, hla, SCCmecIII, and/or SCCmecV) was detected in 48% of the isolates. This study suggests that wild European hake destined for human consumption could act as a vector of CoNS carrying antibiotic resistance genes and/or virulence factors.
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Affiliation(s)
- Lara Díaz-Formoso
- Grupo de Seguridad y Calidad de los Alimentos por Bacterias Lácticas, Bacteriocinas y Probióticos (Grupo SEGABALBP), Sección Departamental de Nutrición y Ciencia de los Alimentos (Nutrición, Bromatología, Higiene y Seguridad Alimentaria), Facultad de Veterinaria, Universidad Complutense de Madrid, Avda. Puerta de Hierro, s/n, 28040 Madrid, Spain; (L.D.-F.); (D.C.); (P.E.H.); (J.B.); (L.M.C.)
| | - Vanessa Silva
- Microbiology and Antibiotic Resistance Team (MicroART), Department of Veterinary Sciences, University of Trás-os-Montes and Alto Douro (UTAD), 5000-801 Vila Real, Portugal; (V.S.); (P.P.)
- Department of Genetics and Biotechnology, University of Trás-os-Montes and Alto Douro (UTAD), 5000-801 Vila Real, Portugal;
- Functional Genomics and Proteomics Unit, University of Trás-os-Montes and Alto Douro (UTAD), 5000-801 Vila Real, Portugal
- LAQV-REQUIMTE, Department of Chemistry, NOVA School of Science and Technology, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
| | - Diogo Contente
- Grupo de Seguridad y Calidad de los Alimentos por Bacterias Lácticas, Bacteriocinas y Probióticos (Grupo SEGABALBP), Sección Departamental de Nutrición y Ciencia de los Alimentos (Nutrición, Bromatología, Higiene y Seguridad Alimentaria), Facultad de Veterinaria, Universidad Complutense de Madrid, Avda. Puerta de Hierro, s/n, 28040 Madrid, Spain; (L.D.-F.); (D.C.); (P.E.H.); (J.B.); (L.M.C.)
| | - Javier Feito
- Grupo de Seguridad y Calidad de los Alimentos por Bacterias Lácticas, Bacteriocinas y Probióticos (Grupo SEGABALBP), Sección Departamental de Nutrición y Ciencia de los Alimentos (Nutrición, Bromatología, Higiene y Seguridad Alimentaria), Facultad de Veterinaria, Universidad Complutense de Madrid, Avda. Puerta de Hierro, s/n, 28040 Madrid, Spain; (L.D.-F.); (D.C.); (P.E.H.); (J.B.); (L.M.C.)
| | - Pablo E. Hernández
- Grupo de Seguridad y Calidad de los Alimentos por Bacterias Lácticas, Bacteriocinas y Probióticos (Grupo SEGABALBP), Sección Departamental de Nutrición y Ciencia de los Alimentos (Nutrición, Bromatología, Higiene y Seguridad Alimentaria), Facultad de Veterinaria, Universidad Complutense de Madrid, Avda. Puerta de Hierro, s/n, 28040 Madrid, Spain; (L.D.-F.); (D.C.); (P.E.H.); (J.B.); (L.M.C.)
| | - Juan Borrero
- Grupo de Seguridad y Calidad de los Alimentos por Bacterias Lácticas, Bacteriocinas y Probióticos (Grupo SEGABALBP), Sección Departamental de Nutrición y Ciencia de los Alimentos (Nutrición, Bromatología, Higiene y Seguridad Alimentaria), Facultad de Veterinaria, Universidad Complutense de Madrid, Avda. Puerta de Hierro, s/n, 28040 Madrid, Spain; (L.D.-F.); (D.C.); (P.E.H.); (J.B.); (L.M.C.)
| | - Gilberto Igrejas
- Department of Genetics and Biotechnology, University of Trás-os-Montes and Alto Douro (UTAD), 5000-801 Vila Real, Portugal;
- Functional Genomics and Proteomics Unit, University of Trás-os-Montes and Alto Douro (UTAD), 5000-801 Vila Real, Portugal
- LAQV-REQUIMTE, Department of Chemistry, NOVA School of Science and Technology, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
| | - Rosa del Campo
- Servicio de Microbiología, Hospital Universitario Ramón y Cajal, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), 28034 Madrid, Spain;
| | - Estefanía Muñoz-Atienza
- Grupo de Seguridad y Calidad de los Alimentos por Bacterias Lácticas, Bacteriocinas y Probióticos (Grupo SEGABALBP), Sección Departamental de Nutrición y Ciencia de los Alimentos (Nutrición, Bromatología, Higiene y Seguridad Alimentaria), Facultad de Veterinaria, Universidad Complutense de Madrid, Avda. Puerta de Hierro, s/n, 28040 Madrid, Spain; (L.D.-F.); (D.C.); (P.E.H.); (J.B.); (L.M.C.)
| | - Patrícia Poeta
- Microbiology and Antibiotic Resistance Team (MicroART), Department of Veterinary Sciences, University of Trás-os-Montes and Alto Douro (UTAD), 5000-801 Vila Real, Portugal; (V.S.); (P.P.)
- LAQV-REQUIMTE, Department of Chemistry, NOVA School of Science and Technology, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
- CECAV—Veterinary and Animal Research Centre, University of Trás-os-Montes and Alto Douro (UTAD), 5000-801 Vila Real, Portugal
- Associate Laboratory for Animal and Veterinary Science (AL4AnimalS), University of Trás-os-Montes and Alto Douro (UTAD), 5000-801 Vila Real, Portugal
| | - Luis M. Cintas
- Grupo de Seguridad y Calidad de los Alimentos por Bacterias Lácticas, Bacteriocinas y Probióticos (Grupo SEGABALBP), Sección Departamental de Nutrición y Ciencia de los Alimentos (Nutrición, Bromatología, Higiene y Seguridad Alimentaria), Facultad de Veterinaria, Universidad Complutense de Madrid, Avda. Puerta de Hierro, s/n, 28040 Madrid, Spain; (L.D.-F.); (D.C.); (P.E.H.); (J.B.); (L.M.C.)
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Chen JHK, Leung HY, Wong CMC, Yuen KY, Cheng VCC. Prevalence and Characteristics of Invasive Staphylococcus argenteus among Patients with Bacteremia in Hong Kong. Microorganisms 2023; 11:2435. [PMID: 37894094 PMCID: PMC10609611 DOI: 10.3390/microorganisms11102435] [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: 09/15/2023] [Revised: 09/25/2023] [Accepted: 09/25/2023] [Indexed: 10/29/2023] Open
Abstract
Staphylococcus argenteus is a novel Staphylococcus species derived from Staphylococcus aureus. Information on the prevalence and genetic characteristics of invasive S. argenteus in Asia is limited. In this study, 275 invasive S. aureus complex strains were retrieved from blood culture specimens in Hong Kong and re-analyzed using MALDI-TOF mass spectrometry and an in-house multiplex real-time PCR for S. argenteus. The prevalence of invasive S. argenteus in Hong Kong was found to be 4.0% (11/275). These strains were primarily susceptible to commonly used antibiotics, except penicillin. Whole-genome sequencing revealed the circulation of three S. argenteus genotypes (ST-2250, ST-1223, and ST-2854) in Hong Kong, with ST-2250 and ST-1223 being the predominant genotypes. The local ST-2250 and ST-1223 strains showed close phylogenetic relationships with isolates from mainland China. Antimicrobial-resistant genes (fosB, tet-38, mepA, blaI, blaZ) could be found in nearly all local S. argenteus strains. The ST-1223 and ST-2250 genotypes carried multiple staphylococcal enterotoxin genes that could cause food poisoning and toxic shock syndrome. The CRISPR/Cas locus was observed only in the ST-2250 strains. This study provides the first report on the molecular epidemiology of invasive S. argenteus in Hong Kong, and further analysis is needed to understand its transmission reservoir.
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Affiliation(s)
- Jonathan H. K. Chen
- Department of Microbiology, Queen Mary Hospital, Hong Kong SAR, China; (H.-Y.L.); (V.C.C.C.)
- Department of Microbiology, School of Clinical Medicine, The University of Hong Kong, Hong Kong SAR, China; (C.M.C.W.); (K.-Y.Y.)
| | - Hoi-Yi Leung
- Department of Microbiology, Queen Mary Hospital, Hong Kong SAR, China; (H.-Y.L.); (V.C.C.C.)
| | - Charles M. C. Wong
- Department of Microbiology, School of Clinical Medicine, The University of Hong Kong, Hong Kong SAR, China; (C.M.C.W.); (K.-Y.Y.)
| | - Kwok-Yung Yuen
- Department of Microbiology, School of Clinical Medicine, The University of Hong Kong, Hong Kong SAR, China; (C.M.C.W.); (K.-Y.Y.)
| | - Vincent C. C. Cheng
- Department of Microbiology, Queen Mary Hospital, Hong Kong SAR, China; (H.-Y.L.); (V.C.C.C.)
- Infection Control Team, Queen Mary Hospital, Hong Kong West Cluster, Hong Kong SAR, China
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Zhang H, Zhang C, Nie X, Wu Y, Yang C, Jiang W, Gu Y. Pleiotropic Regulator GssR Positively Regulates Autotrophic Growth of Gas-Fermenting Clostridium ljungdahlii. Microorganisms 2023; 11:1968. [PMID: 37630531 PMCID: PMC10458427 DOI: 10.3390/microorganisms11081968] [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: 07/04/2023] [Revised: 07/29/2023] [Accepted: 07/30/2023] [Indexed: 08/27/2023] Open
Abstract
Clostridium ljungdahlii is a representative autotrophic acetogen capable of producing multiple chemicals from one-carbon gases (CO2/CO). The metabolic and regulatory networks of this carbon-fixing bacterium are interesting, but still remain minimally explored. Here, based on bioinformatics analysis followed by functional screening, we identified a RpiR family transcription factor (TF) that can regulate the autotrophic growth and carbon fixation of C. ljungdahlii. After deletion of the corresponding gene, the resulting mutant strain exhibited significantly impaired growth in gas fermentation, thus reducing the production of acetic acid and ethanol. In contrast, the overexpression of this TF gene could promote cell growth, indicating a positive regulatory effect of this TF in C. ljungdahlii. Thus, we named the TF as GssR (growth and solvent synthesis regulator). Through the following comparative transcriptomic analysis and biochemical verification, we discovered three important genes (encoding pyruvate carboxylase, carbon hunger protein CstA, and a BlaI family transcription factor) that were directly regulated by GssR. Furthermore, an upstream regulator, BirA, that could directly bind to gssR was found; thus, these two regulators may form a cascade regulation and jointly affect the physiology and metabolism of C. ljungdahlii. These findings substantively expand our understanding on the metabolic regulation of carbon fixation in gas-fermenting Clostridium species.
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Affiliation(s)
- Huan Zhang
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Can Zhang
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaoqun Nie
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuwei Wu
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chen Yang
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China
| | - Weihong Jiang
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China
| | - Yang Gu
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China
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Hou Z, Liu L, Wei J, Xu B. Progress in the Prevalence, Classification and Drug Resistance Mechanisms of Methicillin-Resistant Staphylococcus aureus. Infect Drug Resist 2023; 16:3271-3292. [PMID: 37255882 PMCID: PMC10226514 DOI: 10.2147/idr.s412308] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 05/12/2023] [Indexed: 06/01/2023] Open
Abstract
Staphylococcus aureus is a common human pathogen with a variety of virulence factors, which can cause multiple infectious diseases. In recent decades, due to the constant evolution and the abuse of antibiotics, Staphylococcus aureus was becoming more resistant, the infection rate of MRSA remained high, and clinical treatment of MRSA became more difficult. The genetic diversity of MRSA was mainly represented by the continuous emergence of epidemic strains, resulting in the constant changes of epidemic clones. Different classes of MRSA resulted in different epidemics and resistance characteristics, which could affect the clinical symptoms and treatments. MRSA had also spread from traditional hospitals to community and livestock environments, and the new clones established a relationship between animals and humans, promoting further evolution of MRSA. Since the resistance mechanism of MRSA is very complex, it is important to clarify these resistance mechanisms at the molecular level for the treatment of infectious diseases. We firstly described the diversity of SCCmec elements, and discussed the types of SCCmec, its drug resistance mechanisms and expression regulations. Then, we described how the vanA operon makes Staphylococcus aureus resistant to vancomycin and its expression regulation. Finally, a brief introduction was given to the drug resistance mechanisms of biofilms and efflux pump systems. Analyzing the resistance mechanism of MRSA can help study new anti-infective drugs and alleviate the evolution of MRSA. At the end of the review, we summarized the treatment strategies for MRSA infection, including antibiotics, anti-biofilm agents and efflux pump inhibitors. To sum up, here we reviewed the epidemic characteristics of Staphylococcus aureus, summarized its classifications, drug resistance mechanisms of MRSA (SCCmec element, vanA operon, biofilm and active efflux pump system) and novel therapy strategies, so as to provide a theoretical basis for the treatment of MRSA infection.
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Affiliation(s)
- Zhuru Hou
- Department of Basic Medicine, Fenyang College of Shanxi Medical University, Fenyang, People’s Republic of China
- Key Laboratory of Lvliang for Clinical Molecular Diagnostics, Fenyang, People’s Republic of China
| | - Ling Liu
- Key Laboratory of Lvliang for Clinical Molecular Diagnostics, Fenyang, People’s Republic of China
- Department of Medical Laboratory Science, Fenyang College of Shanxi Medical University, Fenyang, People’s Republic of China
- Department of Clinical Laboratory, Fenyang Hospital of Shanxi Province, Fenyang, People’s Republic of China
| | - Jianhong Wei
- Department of Basic Medicine, Fenyang College of Shanxi Medical University, Fenyang, People’s Republic of China
| | - Benjin Xu
- Key Laboratory of Lvliang for Clinical Molecular Diagnostics, Fenyang, People’s Republic of China
- Department of Medical Laboratory Science, Fenyang College of Shanxi Medical University, Fenyang, People’s Republic of China
- Department of Clinical Laboratory, Fenyang Hospital of Shanxi Province, Fenyang, People’s Republic of China
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Rozman NAS, Yenn TW, Ring LC, Ab Rashid S, Wen-Nee T, Lim JW. 2-Octylcyclopentanone Inhibits Beta Lactam Resistant Diabetic Wound Pathogens. Trop Life Sci Res 2023; 34:279-291. [PMID: 37065798 PMCID: PMC10093773 DOI: 10.21315/tlsr2023.34.1.15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 05/31/2022] [Indexed: 04/18/2023] Open
Abstract
Microbial infection is a frequent complication of diabetic foot ulcers, with up to 82% of ulcers being infected at the initial stage of diabetes. Furthermore, the emergence of beta lactam resistant pathogens managed to eliminate the use of beta lactam antibiotics as a chemotherapeutic alternative. This further increases the amputation and mortality rate. Hence, the aim of this study is to evaluate antimicrobial efficacy of a ketone derivative 2-octylcyclopentanone against diabetic wound pathogens. The inhibitory activity of the compound was determined using disc diffusion and broth microdilution assay. Generally, 2-octylcyclopentanone showed broad-spectrum antimicrobial activity, particularly against beta lactam resistant pathogens. The compound showed comparably better antimicrobial activity than all reference antibiotics, including chloramphenicol, streptomycin, ampicillin and penicillin. In addition, the same compound also inhibits a clinically isolated Pseudonomas aeruginosa that was resistant to all reference antibiotics. The activity was microbicidal based on the low minimal lethality concentration recorded, particularly on MRSA, P. aeruginosa and Candida utilis. The killing efficiency of the compound was concentration dependent. During kill curve analysis, the inhibitory activity of 2-octylcyclopentanone was concentration and time-dependent. 99.9% of reduction of bacterial growth was observed. MRSA and P. aeruginosa, two significant diabetic wound infections, are totally inhibited by the molecule at a concentration of minimum lethality concentration. In short, 2-octylcyclopentanone exhibited significant inhibitory towards wide range of diabetic wound pathogens. Which is considered crucial since it will provide a safe and effective alternative treatment for diabetic ulcer infection.
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Affiliation(s)
- Nur Amiera Syuhada Rozman
- Universiti Kuala Lumpur, Branch Campus Malaysian Institute of Chemical and Bioengineering Technology, Lot 1988 Kawasan Perindustrian Bandar Vendor, Taboh Naning, 78000 Alor Gajah, Melaka, Malaysia
| | - Tong Woei Yenn
- Universiti Kuala Lumpur, Branch Campus Malaysian Institute of Chemical and Bioengineering Technology, Lot 1988 Kawasan Perindustrian Bandar Vendor, Taboh Naning, 78000 Alor Gajah, Melaka, Malaysia
- Universiti Kuala Lumpur – Institute of Medical Science Technology, A1, 1, Jalan TKS 1, Taman Kajang Sentral, 43000 Kajang, Selangor
- Corresponding author:
| | - Leong Chean Ring
- Universiti Kuala Lumpur, Branch Campus Malaysian Institute of Chemical and Bioengineering Technology, Lot 1988 Kawasan Perindustrian Bandar Vendor, Taboh Naning, 78000 Alor Gajah, Melaka, Malaysia
| | - Syarifah Ab Rashid
- Universiti Kuala Lumpur, Branch Campus Malaysian Institute of Chemical and Bioengineering Technology, Lot 1988 Kawasan Perindustrian Bandar Vendor, Taboh Naning, 78000 Alor Gajah, Melaka, Malaysia
| | - Tan Wen-Nee
- Chemistry Section, School of Distance Education, Universiti Sains Malaysia, 11800 USM, Pulau Pinang, Malaysia
| | - Jun Wei Lim
- Department of Fundamental and Applied Sciences, Institute of Sustainable Building, Centre for Biofuel and Biochemical Research, Universiti Teknologi PETRONAS, 32610 Seri Iskandar, Perak, Malaysia
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Cao J, Zhang H, He Z, Piao Z, Zong X, Sun B. Genotypic and Phenotypic Characterization of Some psms Hypervirulent Clinical Isolates of Staphylococcus aureus in a Tertiary Hospital in Hefei, Anhui. Infect Drug Resist 2023; 16:1471-1484. [PMID: 36949844 PMCID: PMC10025015 DOI: 10.2147/idr.s399688] [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: 11/30/2022] [Accepted: 02/17/2023] [Indexed: 03/15/2023] Open
Abstract
Background Staphylococcus aureus is a highly successful pathogen that can cause various infectious diseases, from relatively mild skin infections to life-threatening severe systemic diseases. The widespread pathogenicity of S. aureus is mainly due to its ability to produce many virulence factors that help destroy various host cells, causing disease. Our primary goal in this study was to explore the genes of highly virulent strains, to identify genes closely associated with high virulence, and to provide ideas for the treatment of infection by highly virulent clinical strains. Results This study collected 221 clinical strains from The First Affiliated Hospital Of The University of Science and Technology of China (USTC); their hemolytic abilities were tested. Eight isolates were selected based on their highly hemolytic ability and tested their hemolytic activity again; their phenotypes and gene sequences were also explored. Whole-genome sequencing (WGS) showed six plasmids (pN315, pNE131, pSJH901, pSJH101, SAP106B, and MSSA476), eight antibiotic resistance genes [blaR1, blaI, blaZ, mecA, erm(C), erm(T), tet(38), and fosB-Saur] and seventy-two virulence related genes. Three highly virulent strains, namely X21111206, 21092239, and 21112607, were found according the Galleria mellonella infection model. Therefore, we selected 10 representative virulence genes for qRT-PCR: psmα, psmβ, hlgA, hlgB, hlgC, hla, clfA, clfB, spa, and sak. Among them, the expression levels of psmα and psmβ, the three isolates, were significantly higher than the positive control NCTC8325. Conclusion Significant differences appear in the expression of virulence genes in the highly virulent strains, particularly the psmα and psmβ, It may be that the high expression of psm gene is the cause of the high virulence of Staphylococcus aureus. We can reduce the pathogenicity of Staphylococcus aureus by inhibiting the expression of psm gene, which may provide a strong basis for psm as a new target for clinical treatment of S. aureus infection.
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Affiliation(s)
- Jiaxin Cao
- College of Life Science and Technology, Mudanjiang Normal University, Mudanjiang, People’s Republic of China
- School of Life Science and Medicine, University of Science and Technology of China, Hefei, People’s Republic of China
| | - Huimin Zhang
- College of Life Science and Technology, Mudanjiang Normal University, Mudanjiang, People’s Republic of China
- School of Life Science and Medicine, University of Science and Technology of China, Hefei, People’s Republic of China
| | - Zhien He
- School of Life Science and Medicine, University of Science and Technology of China, Hefei, People’s Republic of China
| | - Zhongwan Piao
- College of Life Science and Technology, Mudanjiang Normal University, Mudanjiang, People’s Republic of China
- Correspondence: Baolin Sun; Zhongwan Piao, Email ;
| | - Xianchun Zong
- College of Life Science and Technology, Mudanjiang Normal University, Mudanjiang, People’s Republic of China
| | - Baolin Sun
- College of Life Science and Technology, Mudanjiang Normal University, Mudanjiang, People’s Republic of China
- School of Life Science and Medicine, University of Science and Technology of China, Hefei, People’s Republic of China
- Correspondence: Baolin Sun; Zhongwan Piao, Email ;
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Li G, Walker MJ, De Oliveira DMP. Vancomycin Resistance in Enterococcus and Staphylococcus aureus. Microorganisms 2022; 11:microorganisms11010024. [PMID: 36677316 PMCID: PMC9866002 DOI: 10.3390/microorganisms11010024] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 12/19/2022] [Accepted: 12/19/2022] [Indexed: 12/24/2022] Open
Abstract
Enterococcus faecalis, Enterococcus faecium and Staphylococcus aureus are both common commensals and major opportunistic human pathogens. In recent decades, these bacteria have acquired broad resistance to several major classes of antibiotics, including commonly employed glycopeptides. Exemplified by resistance to vancomycin, glycopeptide resistance is mediated through intrinsic gene mutations, and/or transferrable van resistance gene cassette-carrying mobile genetic elements. Here, this review will discuss the epidemiology of vancomycin-resistant Enterococcus and S. aureus in healthcare, community, and agricultural settings, explore vancomycin resistance in the context of van and non-van mediated resistance development and provide insights into alternative therapeutic approaches aimed at treating drug-resistant Enterococcus and S. aureus infections.
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Fountain K, Barbon A, Gibbon MJ, Lloyd DH, Loeffler A, Feil EJ. Staphylococcus aureus lineages associated with a free-ranging population of the fruit bat Pteropus livingstonii retained over 25 years in captivity. Sci Rep 2022; 12:13457. [PMID: 35931727 PMCID: PMC9355961 DOI: 10.1038/s41598-022-17835-3] [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: 02/28/2022] [Accepted: 08/01/2022] [Indexed: 11/09/2022] Open
Abstract
Conservation of endangered species has become increasingly complex, and costly interventions to protect wildlife require a robust scientific evidence base. This includes consideration of the role of the microbiome in preserving animal health. Captivity introduces stressors not encountered in the wild including environmental factors and exposure to exotic species, humans and antimicrobial drugs. These stressors may perturb the microbiomes of wild animals, with negative consequences for their health and welfare and hence the success of the conservation project, and ultimately the risk of release of non-native organisms into native ecosystems. We compared the genomes of Staphylococcus aureus colonising critically endangered Livingstone’s fruit bats (Pteropus livingstonii) which have been in a captive breeding programme for 25 years, with those from bats in the endemic founder population free ranging in the Comoros Republic. Using whole genome sequencing, we compared 47 isolates from captive bats with 37 isolates from those free ranging in the Comoros Republic. Our findings demonstrate unexpected resilience in the bacteria carried, with the captive bats largely retaining the same two distinctive lineages carried at the time of capture. In addition, we found evidence of genomic changes which suggest specific adaptations to the bat host.
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Affiliation(s)
- Kay Fountain
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK.
| | - Alberto Barbon
- North of England Zoological Society (Chester Zoo), Caughall Road, Upton by Chester, Chester, Cheshire, CH2 1LH, UK
| | - Marjorie J Gibbon
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK
| | - David H Lloyd
- Department of Clinical Science and Services, Royal Veterinary College, North Mymms, Hatfield, Hertfordshire, AL9 7TA, UK
| | - Anette Loeffler
- Department of Clinical Science and Services, Royal Veterinary College, North Mymms, Hatfield, Hertfordshire, AL9 7TA, UK
| | - Edward J Feil
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK
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A protease-mediated mechanism regulates the cytochrome c 6/plastocyanin switch in Synechocystis sp. PCC 6803. Proc Natl Acad Sci U S A 2021; 118:2017898118. [PMID: 33495331 DOI: 10.1073/pnas.2017898118] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
After the Great Oxidation Event (GOE), iron availability was greatly decreased, and photosynthetic organisms evolved several alternative proteins and mechanisms. One of these proteins, plastocyanin, is a type I blue-copper protein that can replace cytochrome c 6 as a soluble electron carrier between cytochrome b 6 f and photosystem I. In most cyanobacteria, expression of these two alternative proteins is regulated by copper availability, but the regulatory system remains unknown. Herein, we provide evidence that the regulatory system is composed of a BlaI/CopY-family transcription factor (PetR) and a BlaR-membrane protease (PetP). PetR represses petE (plastocyanin) expression and activates petJ (cytochrome c 6), while PetP controls PetR levels in vivo. Using whole-cell extracts, we demonstrated that PetR degradation requires both PetP and copper. Transcriptomic analysis revealed that the PetRP system regulates only four genes (petE, petJ, slr0601, and slr0602), highlighting its specificity. Furthermore, the presence of petE and petRP in early branching cyanobacteria indicates that acquisition of these genes could represent an early adaptation to decreased iron bioavailability following the GOE.
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Ridyard KE, Overhage J. The Potential of Human Peptide LL-37 as an Antimicrobial and Anti-Biofilm Agent. Antibiotics (Basel) 2021; 10:antibiotics10060650. [PMID: 34072318 PMCID: PMC8227053 DOI: 10.3390/antibiotics10060650] [Citation(s) in RCA: 72] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 05/20/2021] [Accepted: 05/25/2021] [Indexed: 02/06/2023] Open
Abstract
The rise in antimicrobial resistant bacteria threatens the current methods utilized to treat bacterial infections. The development of novel therapeutic agents is crucial in avoiding a post-antibiotic era and the associated deaths from antibiotic resistant pathogens. The human antimicrobial peptide LL-37 has been considered as a potential alternative to conventional antibiotics as it displays broad spectrum antibacterial and anti-biofilm activities as well as immunomodulatory functions. While LL-37 has shown promising results, it has yet to receive regulatory approval as a peptide antibiotic. Despite the strong antimicrobial properties, LL-37 has several limitations including high cost, lower activity in physiological environments, susceptibility to proteolytic degradation, and high toxicity to human cells. This review will discuss the challenges associated with making LL-37 into a viable antibiotic treatment option, with a focus on antimicrobial resistance and cross-resistance as well as adaptive responses to sub-inhibitory concentrations of the peptide. The possible methods to overcome these challenges, including immobilization techniques, LL-37 delivery systems, the development of LL-37 derivatives, and synergistic combinations will also be considered. Herein, we describe how combination therapy and structural modifications to the sequence, helicity, hydrophobicity, charge, and configuration of LL-37 could optimize the antimicrobial and anti-biofilm activities of LL-37 for future clinical use.
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Fisher JF, Mobashery S. β-Lactams against the Fortress of the Gram-Positive Staphylococcus aureus Bacterium. Chem Rev 2021; 121:3412-3463. [PMID: 33373523 PMCID: PMC8653850 DOI: 10.1021/acs.chemrev.0c01010] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The biological diversity of the unicellular bacteria-whether assessed by shape, food, metabolism, or ecological niche-surely rivals (if not exceeds) that of the multicellular eukaryotes. The relationship between bacteria whose ecological niche is the eukaryote, and the eukaryote, is often symbiosis or stasis. Some bacteria, however, seek advantage in this relationship. One of the most successful-to the disadvantage of the eukaryote-is the small (less than 1 μm diameter) and nearly spherical Staphylococcus aureus bacterium. For decades, successful clinical control of its infection has been accomplished using β-lactam antibiotics such as the penicillins and the cephalosporins. Over these same decades S. aureus has perfected resistance mechanisms against these antibiotics, which are then countered by new generations of β-lactam structure. This review addresses the current breadth of biochemical and microbiological efforts to preserve the future of the β-lactam antibiotics through a better understanding of how S. aureus protects the enzyme targets of the β-lactams, the penicillin-binding proteins. The penicillin-binding proteins are essential enzyme catalysts for the biosynthesis of the cell wall, and understanding how this cell wall is integrated into the protective cell envelope of the bacterium may identify new antibacterials and new adjuvants that preserve the efficacy of the β-lactams.
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Affiliation(s)
- Jed F Fisher
- Department of Chemistry and Biochemistry, McCourtney Hall, University of Notre Dame, Notre Dame Indiana 46556, United States
| | - Shahriar Mobashery
- Department of Chemistry and Biochemistry, McCourtney Hall, University of Notre Dame, Notre Dame Indiana 46556, United States
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Chowdhury NN, Cox AR, Wiesner MR. Nanoparticles as vectors for antibiotic resistance: The association of silica nanoparticles with environmentally relevant extracellular antibiotic resistance genes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 761:143261. [PMID: 33223180 DOI: 10.1016/j.scitotenv.2020.143261] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 10/04/2020] [Accepted: 10/20/2020] [Indexed: 05/09/2023]
Abstract
A relevant but yet unconsidered subset of particles that may alter the fate of extracellular antibiotic resistance genes (eARGs) are nano-scale particles (NPs), which are ubiquitous in natural environments and have unique properties. In this study, sorption isotherms were developed describing the association of linear DNA fragments isolated from widespread eARGs (blaI and nptII) with either micon-sized kaolinite or silica nanoparticles (SNPs), to determine if sorption capacity was enhanced at the nanoscale. For each isotherm, eARG fragments were added at five starting concentrations (5-40 μg/mL) to mixed batch systems with 0.25 g of particles and nuclease-free water. Sorption was quantified by the removal of DNA from solution, as detected by a Qubit fluorimeter. Isotherms were developed for eARGs of various fragment lengths (508, 680 and 861 bp), guanine-cytosine (GC) contents (34%, 47% and 54%) and both double and single stranded eARGs, to assess the impact of DNA properties on particle association. Sorption isotherms were also developed in systems with added humic acid and/or CaCl2, to assess the impact of these environmental parameters on sorption. FTIR analysis was performed to analyze the conformation of sorbed eARGs. Desorption of eARGs was studied by quantifying the removal of eDNA from washed and vortexed post-sorption particles. Statistically significant irreversible sorption of eARGs to environmentally relevant NPs (humic acid functionalized silica nanoparticles) was demonstrated for the first time. Nano-emergent properties did not increase sorption capacity of eARGs, but led to a unique compressed conformation of sorbed eARGs. The addition of humic acid, increased CaCl2 concentration and small DNA fragment size favored sorption. NPs showed a slight preference for the sorption of single-stranded DNA over double-stranded DNA. These findings suggest that NP association with eARGs may be a significant and unique environmental phenomenon that could influence the spread of antibiotic resistance.
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Affiliation(s)
- Nadratun N Chowdhury
- Department of Civil and Environmental Engineering, Duke Hudson Hall, Box 90287, Durham, NC 27708-0287, USA.
| | - Akylah R Cox
- Department of Civil and Environmental Engineering, Duke Hudson Hall, Box 90287, Durham, NC 27708-0287, USA
| | - Mark R Wiesner
- Department of Civil and Environmental Engineering, Duke Hudson Hall, Box 90287, Durham, NC 27708-0287, USA
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Hornung BVH, Kuijper EJ, Smits WK. An in silico survey of Clostridioides difficile extrachromosomal elements . Microb Genom 2020; 5. [PMID: 31526450 PMCID: PMC6807378 DOI: 10.1099/mgen.0.000296] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The Gram-positive enteropathogen Clostridioides difficile (Clostridium difficile) is the major cause of healthcare-associated diarrhoea and is also an important cause of community-acquired infectious diarrhoea. Considering the burden of the disease, many studies have employed whole-genome sequencing of bacterial isolates to identify factors that contribute to virulence and pathogenesis. Though extrachromosomal elements (ECEs) such as plasmids are important for these processes in other bacteria, the few characterized plasmids of C. difficile have no relevant functions assigned and no systematic identification of plasmids has been carried out to date. Here, we perform an in silico analysis of publicly available sequence data to show that ~13 % of all C. difficile strains contain ECEs, with 1–6 elements per strain. Our approach identifies known plasmids (e.g. pCD6, pCD630 and cloning plasmids) and six novel putative plasmid families. Our study shows that plasmids are abundant and may encode functions that are relevant for C. difficile physiology. The newly identified plasmids may also form the basis for the construction of novel cloning plasmids for C. difficile that are compatible with existing tools.
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Affiliation(s)
- Bastian V H Hornung
- Department of Medical Microbiology, Leiden University Medical Center, PO Box 9600, 2300RC, Leiden, The Netherlands
| | - Ed J Kuijper
- Netherlands Centre for One Health, The Netherlands.,Department of Medical Microbiology, Leiden University Medical Center, PO Box 9600, 2300RC, Leiden, The Netherlands
| | - Wiep Klaas Smits
- Netherlands Centre for One Health, The Netherlands.,Department of Medical Microbiology, Leiden University Medical Center, PO Box 9600, 2300RC, Leiden, The Netherlands.,Centre for Microbial Cell Biology, Leiden, The Netherlands
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Lee YS, Gong R, Lee D, Lee J, Choi D, Kim GS, Lee S. Potentiating activity of rhein in targeting of resistance genes in methicillin-resistant Staphylococcus aureus. ASIAN PAC J TROP MED 2019. [DOI: 10.4103/1995-7645.250339] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Yenn TW, Arslan Khan M, Amiera Syuhada N, Chean Ring L, Ibrahim D, Tan WN. Stigmasterol: An adjuvant for beta lactam antibiotics against beta-lactamase positive clinical isolates. Steroids 2017; 128:68-71. [PMID: 29104098 DOI: 10.1016/j.steroids.2017.10.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 10/26/2017] [Accepted: 10/30/2017] [Indexed: 10/18/2022]
Abstract
The emergence of beta lactamase producing bacterial strains eliminated the use of beta lactam antibiotics as chemotherapeutic alternative. Beta lactam antibiotics can be coupled with non-antibiotic adjuvants to combat these multidrug resistant strains. We study the synergistic antibiotic effect of stigmasterol as adjuvant of ampicillin against clinical isolates. Ampicillin was used in this study as a beta lactam antibiotic model. All test bacteria were beta lactamase producing clinical isolates. The combination showed significantly better antibiotic activity on all bacteria tested. The two test substances have synergistic antibiotic activity, and the effect was observed in both Gram positive and Gram negative bacteria. The synergistic antibiotic effect of stigmasterol and ampicillin was evident by the low fractional inhibitory concentration (FIC) index on Checkerboard Assay. The results suggest that the combination of ampicillin and stigmasterol acts additively in the treatment of infections caused by beta-lactamase producing pathogens. In bacterial growth reduction assay, ampicillin and stigmasterol alone exhibited very weak inhibitory effect on the bacterial growth, relative to ethanol control. Comparatively, combination of stigmasterol-ampicillin greatly reduced the colony counts at least by 98.7%. In conclusion, we found synergistic effects of stigmasterol and ampicillin against beta lactamase producing clinical isolates. This finding is important as it shows potential application of stigmasterol as an antibiotic adjuvant.
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Affiliation(s)
- Tong Woei Yenn
- Universiti Kuala Lumpur, Malaysian Institute of Chemical and Bioengineering Technology, Lot 1988 Kawasan Perindustrian Bandar Vendor, Taboh Naning, 78000 Alor Gajah, Melaka, Malaysia.
| | | | - Nur Amiera Syuhada
- Universiti Kuala Lumpur, Malaysian Institute of Chemical and Bioengineering Technology, Lot 1988 Kawasan Perindustrian Bandar Vendor, Taboh Naning, 78000 Alor Gajah, Melaka, Malaysia
| | - Leong Chean Ring
- Universiti Kuala Lumpur, Malaysian Institute of Chemical and Bioengineering Technology, Lot 1988 Kawasan Perindustrian Bandar Vendor, Taboh Naning, 78000 Alor Gajah, Melaka, Malaysia
| | - Darah Ibrahim
- Industrial Biotechnology Research Laboratory, School of Biological Sciences, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia
| | - Wen-Nee Tan
- School of Distance Education, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia
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Abstract
INTRODUCTION Methicillin-resistant staphylococcus aureus is an emerging problem for the treatment of chronic suppurative otitis media, and also for pediatric tympanostomy tube otorrhea. To date, there are no effective topical antibiotic drugs to treat methicillin-resistant staphylococcus aureus otorrhea. OBJECTIVE In this study, we evaluated the ototoxicity of topical KR-12-a2 solution on the cochlea when it is applied topically in the middle ear of guinea pigs. METHODS The antimicrobial activity of KR-12-a2 against methicillin-resistant staphylococcus aureus strains was examined by using the inhibition zone test. Topical application of KR-12-a2 solution, gentamicin and phosphate buffered saline were applied in the middle ear of the guinea pigs after inserting ventilation tubes. Ototoxicity was assessed by auditory brainstem evoked response and scanning electron microscope examination. RESULTS KR-12-a2 produced an inhibition zone against methicillin-resistant staphylococcus aureus from 6.25 μg. Hearing threshold in the KR-12-a2 and PBS groups were similar to that before ventilation tube insertion. However, the gentamicin group showed elevation of the hearing threshold and there were statistically significant differences compared to the phosphate buffered saline or the KR-12-a2 group. In the scanning electron microscope findings, the KR-12-a2 group showed intact outer hair cells. However, the gentamicin group showed total loss of outer hair cells. In our experiment, topically applied KR-12-a2 solution did not cause hearing loss or cochlear damage in guinea pigs. CONCLUSION In our experiment, topically applied KR-12-a2 solution did not cause hearing loss or cochlear damage in guinea pigs. The KR-12-a2 solution can be used as ototopical drops for treating methicillin-resistant staphylococcus aureus otorrhea; however, further evaluations, such as the definition of optimal concentration and combination, are necessary.
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A Livestock-Associated, Multidrug-Resistant, Methicillin-Resistant Staphylococcus aureus Clonal Complex 97 Lineage Spreading in Dairy Cattle and Pigs in Italy. Appl Environ Microbiol 2015; 82:816-21. [PMID: 26590279 DOI: 10.1128/aem.02854-15] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 11/13/2015] [Indexed: 01/31/2023] Open
Abstract
Pandemic methicillin-resistant Staphylococcus aureus (MRSA) clonal complex 97 (CC97) lineages originated from livestock-to-human host jumps. In recent years, CC97 has become one of the major MRSA lineages detected in Italian farmed animals. The aim of this study was to characterize and analyze differences in MRSA and methicillin-susceptible S. aureus (MSSA) mainly of swine and bovine origins. Forty-seven CC97 isolates, 35 MRSA isolates, and 6 MSSA isolates from different Italian pig and cattle holdings; 5 pig MRSA isolates from Germany; and 1 human MSSA isolate from Spain were characterized by macrorestriction pulsed-field gel electrophoresis (PFGE) analysis, multilocus sequence typing (MLST), spa typing, staphylococcal cassette chromosome mec (SCCmec) typing, and antimicrobial resistance pattern analysis. Virulence and resistance genes were investigated by PCR and microarray analysis. Most of the isolates were of SCCmec type V (SCCmec V), except for two German MRSA isolates (SCCmec III). Five main clusters were identified by PFGE, with the German isolates (clusters I and II) showing 60.5% similarity with the Italian isolates, most of which (68.1%) grouped into cluster V. All CC97 isolates were Panton-Valentine leukocidin (PVL) negative, and a few (n = 7) tested positive for sak or scn. All MRSA isolates were multidrug resistant (MDR), and the main features were erm(B)- or erm(C)-mediated (n = 18) macrolide-lincosamide-streptogramin B resistance, vga(A)-mediated (n = 37) pleuromutilin resistance, fluoroquinolone resistance (n = 33), tet(K) in 32/37 tet(M)-positive isolates, and blaZ in almost all MRSA isolates. Few host-associated differences were detected among CC97 MRSA isolates: their extensive MDR nature in both pigs and dairy cattle may be a consequence of a spillback from pigs of a MRSA lineage that originated in cattle as MSSA and needs further investigation. Measures should be implemented at the farm level to prevent spillover to humans in intensive farming areas.
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