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Zhi XY, Jiang Z, Yang LL, Huang Y. The underlying mechanisms of genetic innovation and speciation in the family Corynebacteriaceae: A phylogenomics approach. Mol Phylogenet Evol 2017; 107:246-255. [DOI: 10.1016/j.ympev.2016.11.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 11/04/2016] [Accepted: 11/14/2016] [Indexed: 01/01/2023]
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van der Heijden IM, de Oliveira LM, Brito GC, Abdala E, Freire MP, Rossi F, D'Albuquerque LAC, Levin ASS, Costa SF. Virulence and resistance profiles of MRSA isolates in pre- and post-liver transplantation patients using microarray. J Med Microbiol 2016; 65:1060-1073. [PMID: 27473165 DOI: 10.1099/jmm.0.000324] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) screening plays a great role in preventing infections in surgical patients. This study aims to evaluate clonality, virulence and resistance of MRSA in pre- and post-liver transplantation (LT) patients. Nasal and groin swabs of 190 patients were collected. PCR for virulence genes and staphylococcal cassette chromosome mec (SCCmec) types, microarray, PFGE, multilocus sequence typing and MIC were performed. MRSA carriers were detected in 20.5 % (39/190) of the patients. However, only three colonized patients developed infections post-LT. Sixty-nine MRSA isolates were identified, and the most frequent SCCmec type was type II (29/69; 42.0 %). Most isolates (57/69; 82.6 %) were susceptible to trimethoprim-sulfamethoxazole (TMP/SMX) and harboured the lukD, lukE, clf and fnbA genes as determined by PCR. Five sequence types (ST) were identified among nine clones; 36.2 % (25/69) isolates belonged to a predominant clone (ST105 and SCCmec type II) that was susceptible to TMP/SMX, mupirocin and chlorhexidine, which had 87.9 % similarity with the New York/Japan clone. The array showed virulence difference in isolates of the same clone and patients and that colonized isolates (pre-LT patients) were less virulent than those post-LT and those infected. Therefore, despite the high frequency of MRSA colonization, infection due to MRSA was uncommon in our LT unit. MRSA isolates presented great diversity. Isolates of the same clone expressed different virulence factors by array. Colonizing isolates pre-LT expressed less virulent factors than post-LT and infecting isolates.
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Affiliation(s)
- Inneke Marie van der Heijden
- Department of Infectious Diseases, Laboratory of Medical Investigation (LIM 54), Hospital das Clínicas - FMUSP, Sao Paulo, Brazil.,Department of Infectious Diseases, FMUSP, University of Sao Paulo, Brazil.,Department of Pathology, Discipline of Microbiology and Immunology, ABC Medicine School, FMABC, Santo André, Brazil
| | - Larissa Marques de Oliveira
- Department of Infectious Diseases, FMUSP, University of Sao Paulo, Brazil.,Department of Infectious Diseases, Laboratory of Medical Investigation (LIM 54), Hospital das Clínicas - FMUSP, Sao Paulo, Brazil
| | - Glauber Costa Brito
- ICESP - Institute of Cancer of Sao Paulo, FFM, University of Sao Paulo, Brazil
| | - Edson Abdala
- Department of Infectious Diseases, FMUSP, University of Sao Paulo, Brazil
| | | | - Flavia Rossi
- Department of Pathology, Division of Microbiology of the Central Laboratory (LIM 03), Hospital das Clínicas - FMUSP, University of Sao Paulo, Brazil
| | - Luiz Augusto Carneiro D'Albuquerque
- Liver and Gastrointestinal Transplant Division, Department of Gastroenterology, Hospital das Clínicas - FMUSP, University of Sao Paulo, Brazil
| | - Anna Sara Shafferman Levin
- Department of Infectious Diseases, FMUSP, University of Sao Paulo, Brazil.,Department of Infectious Diseases, Laboratory of Medical Investigation (LIM 54), Hospital das Clínicas - FMUSP, Sao Paulo, Brazil.,Department of Infection Control, Hospital das Clínicas - FMUSP, University of Sao Paulo, Brazil
| | - Silvia Figueiredo Costa
- Department of Infectious Diseases, FMUSP, University of Sao Paulo, Brazil.,Department of Infectious Diseases, Laboratory of Medical Investigation (LIM 54), Hospital das Clínicas - FMUSP, Sao Paulo, Brazil.,Department of Infection Control, Hospital das Clínicas - FMUSP, University of Sao Paulo, Brazil
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de Vries LE, Hasman H, Jurado Rabadán S, Agersø Y. Sequence-Based Characterization of Tn5801-Like Genomic Islands in Tetracycline-Resistant Staphylococcus pseudintermedius and Other Gram-positive Bacteria from Humans and Animals. Front Microbiol 2016; 7:576. [PMID: 27199912 PMCID: PMC4844618 DOI: 10.3389/fmicb.2016.00576] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Accepted: 04/08/2016] [Indexed: 01/18/2023] Open
Abstract
Antibiotic resistance in pathogens is often associated with mobile genetic elements, such as genomic islands (GI) including integrative and conjugative elements (ICEs). These can transfer resistance genes within and between bacteria from humans and/or animals. The aim of this study was to investigate whether Tn5801-like GIs carrying the tetracycline resistance gene, tet(M), are common in Staphylococcus pseudintermedius from pets, and to do an overall sequences-based characterization of Tn5801-like GIs detected in Gram-positive bacteria from humans and animals. A total of 27 tetracycline-resistant S. pseudintermedius isolates from Danish pets (1998–2005) were screened for tet(M) by PCR. Selected isolates (13) were screened for GI- or ICE-specific genes (intTn5801 or xisTn916) and their tet(M) gene was sequenced (Sanger-method). Long-range PCR mappings and whole-genome-sequencing (Illumina) were performed for selected S. pseudintermedius-isolates (seven and three isolates, respectively) as well as for human S. aureus isolates (seven and one isolates, respectively) and one porcine Enterococcus faecium isolate known to carry Tn5801-like GIs. All 27 S. pseudintermedius were positive for tet(M). Out of 13 selected isolates, seven contained Tn5801-like GIs and six contained Tn916-like ICEs. Two different Tn5801-like GI types were detected among S. pseudintermedius (Tn5801 and GI6287) - both showed high similarity compared to GenBank sequences from human pathogens. Two distinct Tn5801-like GI types were detected among the porcine E. faecium and human S. aureus isolates (Tn6014 and GI6288). Tn5801-like GIs were detected in GenBank-sequences from Gram-positive bacteria of human, animal or food origin worldwide. Known Tn5801-like GIs were divided into seven types. The results showed that Tn5801-like GIs appear to be relatively common in tetracycline-resistant S. pseudintermedius in Denmark. Almost identical Tn5801-like GIs were identified in different Gram-positive species of pet and human origin, suggesting that horizontal transfer of these elements has occurred between S. pseudintermedius from pets and human pathogens, including S. aureus.
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Affiliation(s)
- Lisbeth E de Vries
- Department of Technology, Metropolitan University College Copenhagen, Denmark
| | - Henrik Hasman
- National Food Institute, Technical University of Copenhagen Lyngby, Denmark
| | | | - Yvonne Agersø
- National Food Institute, Technical University of Copenhagen Lyngby, Denmark
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Ilczyszyn WM, Sabat AJ, Akkerboom V, Szkarlat A, Klepacka J, Sowa-Sierant I, Wasik B, Kosecka-Strojek M, Buda A, Miedzobrodzki J, Friedrich AW. Clonal Structure and Characterization of Staphylococcus aureus Strains from Invasive Infections in Paediatric Patients from South Poland: Association between Age, spa Types, Clonal Complexes, and Genetic Markers. PLoS One 2016; 11:e0151937. [PMID: 26992009 PMCID: PMC4798296 DOI: 10.1371/journal.pone.0151937] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 03/07/2016] [Indexed: 12/20/2022] Open
Abstract
The aim of current study was to examine clonal structure and genetic profile of invasive Staphylococcus aureus isolates recovered from infants and children treated at the Jagiellonian University Children’s Hospital of Krakow, Poland. The 107 invasive S. aureus isolates, collected between February 2012 and August 2014, were analysed retrospectively. Antimicrobial susceptibility testing, spa typing and DNA microarray analysis were performed to determine clonal distribution, diversity and gene content in regard to patients characteristics. In total, 107 isolates were recovered from 88 patients with clinical symptoms of invasive bacterial infection. The final set of 92 non-duplicate samples included 38 MRSA isolates. Additionally, a set of 54 S. aureus isolates collected during epidemiological screening was genotyped and analysed. There were 72 healthcare-associated (HCA) and 20 community-onset (CO) infection events caused by 33 and 5 MRSA isolates, respectively. The majority of isolates were affiliated with the major European clonal complexes CC5 (t003, spa-CC 002), CC45 (spa-CC 015), CC7 or CC15 (t084, t091, spa-CC 084). Two epidemic clones (CC5-MRSA-II or CC45-MRSA-IV) dominated among MRSA isolates, while MSSA population contained 15 different CCs. The epidemiological screening isolates belonged to similar genetic lineages as those collected from invasive infection cases. The HCA infection events, spa types t003, t2642 or CC5 were significantly associated with infections occurring in neonates and children under 5 years of age. Moreover, carriage of several genetic markers, including erm(A), sea (N315), egc-cluster, chp was significantly higher in isolates obtained from children in this age group. The spa types t091 and t008 were underrepresented among patients aged 5 years or younger, whereas spa type t008, CC8 and presence of splE was associated with infection in children aged 10 years or older. The HCA-MRSA strains were most frequently found in children under 5 years, although the majority of invasive infections was associated with MSSA strains. Moreover, an association between age group of children from the study population and a specific strain genotype (spa type, clonal complex or genetic content) was observed among the patients.
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Affiliation(s)
- Weronika M Ilczyszyn
- Department of Microbiology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | - Artur J Sabat
- Department of Medical Microbiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Viktoria Akkerboom
- Department of Medical Microbiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Anna Szkarlat
- Department of Clinical Microbiology, Children's University Hospital, Jagiellonian University, Krakow, Poland
| | - Joanna Klepacka
- Department of Clinical Microbiology, Children's University Hospital, Jagiellonian University, Krakow, Poland
| | - Iwona Sowa-Sierant
- Department of Clinical Microbiology, Children's University Hospital, Jagiellonian University, Krakow, Poland
| | - Barbara Wasik
- Department of Clinical Microbiology, Children's University Hospital, Jagiellonian University, Krakow, Poland
| | - Maja Kosecka-Strojek
- Department of Microbiology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | - Aneta Buda
- Department of Microbiology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | - Jacek Miedzobrodzki
- Department of Microbiology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | - Alexander W Friedrich
- Department of Medical Microbiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
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Shang W, Hu Q, Yuan W, Cheng H, Yang J, Hu Z, Yuan J, Zhang X, Peng H, Yang Y, Hu X, Li M, Zhu J, Rao X. Comparative Fitness and Determinants for the Characteristic Drug Resistance of ST239-MRSA-III-t030 and ST239-MRSA-III-t037 Strains Isolated in China. Microb Drug Resist 2015; 22:185-92. [PMID: 26565599 DOI: 10.1089/mdr.2015.0226] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Sequence type (ST) 239 with SCCmec type III methicillin-resistant Staphylococcus aureus (ST239-MRSA-III) is the most predominant multidrug-resistant clone in China. The subclone ST239-MRSA-III-t037 has been gradually replaced with ST239-MRSA-III-t030 since 2000. Subclones are characterized by drug resistance profiles. However, the mechanisms of the clonal dynamics and determinants of distinct drug resistance remain poorly understood. In the present study, 12 ST239-MRSA-III-t030 and 12 ST239-MRSA-III-t037 strains were collected from Chongqing, Guangzhou, and Shanghai; these strains were selected and investigated in terms of t030/t037 strain pairs. Independent growth curve assay revealed that the ST239-MRSA-III-t030 strains grew more rapidly, with significantly shorter doubling times, than the ST239-MRSA-III-t037 strains (p < 0.001). The ST239-MRSA-III-t037 strains exhibited slightly to moderately higher (3-13%) fitness cost than the ST239-MRSA-III-t030 strains in a competition assay in vitro. The ST239-MRSA-III-t037 strains yielded lower bacterial loads in the kidneys of the infected mice than the ST239-MRSA-III-t030 rivals in a coinfection assay (p < 0.05). The ST239-MRSA-III-t030 strains were resistant to rifampicin but susceptible to trimethoprim/sulfamethoxazole (SXT). In contrast, the ST239-MRSA-III-t037 strains were susceptible to rifampicin but resistant to SXT. The genetic determinants of the resistance to rifampicin and SXT in the MRSA strains were determined. Our results suggest that the relatively low fitness cost and characteristic drug resistance phenotype can help explain the current predominance of these ST239-MRSA-III-t030 strains in Chinese hospitals.
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Affiliation(s)
- Weilong Shang
- 1 Department of Microbiology, College of Basic Medical Sciences, Third Military Medical University , Chongqing, China
| | - Qiwen Hu
- 1 Department of Microbiology, College of Basic Medical Sciences, Third Military Medical University , Chongqing, China
| | - Wenchang Yuan
- 1 Department of Microbiology, College of Basic Medical Sciences, Third Military Medical University , Chongqing, China .,2 Clinical Laboratory Diagnostic Center, Urumqi General Hospital of PLA , Urumqi, China
| | - Hang Cheng
- 1 Department of Microbiology, College of Basic Medical Sciences, Third Military Medical University , Chongqing, China
| | - Jie Yang
- 1 Department of Microbiology, College of Basic Medical Sciences, Third Military Medical University , Chongqing, China
| | - Zhen Hu
- 1 Department of Microbiology, College of Basic Medical Sciences, Third Military Medical University , Chongqing, China
| | - Jizhen Yuan
- 1 Department of Microbiology, College of Basic Medical Sciences, Third Military Medical University , Chongqing, China
| | - Xiaopeng Zhang
- 1 Department of Microbiology, College of Basic Medical Sciences, Third Military Medical University , Chongqing, China
| | - Huagang Peng
- 1 Department of Microbiology, College of Basic Medical Sciences, Third Military Medical University , Chongqing, China
| | - Yancheng Yang
- 1 Department of Microbiology, College of Basic Medical Sciences, Third Military Medical University , Chongqing, China
| | - Xiaomei Hu
- 1 Department of Microbiology, College of Basic Medical Sciences, Third Military Medical University , Chongqing, China
| | - Ming Li
- 1 Department of Microbiology, College of Basic Medical Sciences, Third Military Medical University , Chongqing, China
| | - Junmin Zhu
- 1 Department of Microbiology, College of Basic Medical Sciences, Third Military Medical University , Chongqing, China
| | - Xiancai Rao
- 1 Department of Microbiology, College of Basic Medical Sciences, Third Military Medical University , Chongqing, China
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Solntsev LA, Starikova VD, Sakharnov NA, Knyazev DI, Utkin OV. Strategy of probe selection for studying mRNAs that participate in receptor-mediated apoptosis signaling. Mol Biol 2015. [DOI: 10.1134/s0026893315030164] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Chen Y, Liu Z, Duo L, Xiong J, Gong Y, Yang J, Wang Z, Wu X, Lu Z, Meng X, Zhao J, Zhang C, Wang F, Zhang Y, Zhang M, Han L. Characterization of Staphylococcus aureus from distinct geographic locations in China: an increasing prevalence of spa-t030 and SCCmec type III. PLoS One 2014; 9:e96255. [PMID: 24763740 PMCID: PMC3999196 DOI: 10.1371/journal.pone.0096255] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 04/04/2014] [Indexed: 11/22/2022] Open
Abstract
Staphylococcus aureus belongs to one of the most common bacteria causing healthcare and community associated infections in China, but their molecular characterization has not been well studied. From May 2011 to June 2012, a total of 322 non-duplicate S. aureus isolates were consecutively collected from seven tertiary care hospitals in seven cities with distinct geographical locations in China, including 171 methicillin sensitive S. aureus (MSSA) and 151 MRSA isolates. All isolates were characterized by spa typing. The presence of virulence genes was tested by PCR. MRSA were further characterized by SCCmec typing. Seventy four and 16 spa types were identified among 168 MSSA and 150 MRSA, respectively. One spa type t030 accounted for 80.1% of all MRSA isolates, which was higher than previously reported, while spa-t037 accounted for only 4.0% of all MRSA isolates. The first six spa types (t309, t189, t034, t377, t078 and t091) accounted for about one third of all MSSA isolates. 121 of 151 MRSA isolates (80.1%) were identified as SCCmec type III. pvl gene was found in 32 MSSA (18.7%) and 5 MRSA (3.3%) isolates, with ST22-MSSA-t309 as the most commonly identified strain. Compared with non-epidemic MRSA clones, epidemic MRSA clones (corresponding to ST239) exhibited a lower susceptibility to rifampin, ciprofloxacin, gentamicin and trimethoprim-sulfamethoxazole, a higher prevalence of sea gene and a lower prevalence of seb, sec, seg, sei and tst genes. The increasing prevalence of multidrug resistant spa-t030 MRSA represents a major public health problem in China.
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Affiliation(s)
- Yong Chen
- Center for Hospital Infection Control, Chinese PLA Institute for Disease Control & Prevention, Academy of Military Medical Sciences, Beijing, China
| | - Zhengxiang Liu
- Department of Clinical Microbiology, Urumqi General Hospital of Lanzhou Military Command, PLA, Urumqi, China
| | - Libo Duo
- Department of Clinical Microbiology, The Second Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Jie Xiong
- Department of Clinical Laboratory, General Hospital of Chengdu Military Command, Chengdu, China
| | - Yanwen Gong
- Department of Clinical Laboratory, General Hospital of Ji'nan Military Command, Ji'nan, China
| | - Jiyong Yang
- Department of Clinical Microbiology, Chinese PLA General Hospital, Beijing, China
| | - Zhanke Wang
- Department of Clinical Laboratory, 94 Hospital of PLA, Nanchang, China
| | - Xuqin Wu
- Department of Clinical Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Zhongyi Lu
- Center for Hospital Infection Control, Chinese PLA Institute for Disease Control & Prevention, Academy of Military Medical Sciences, Beijing, China
| | - Xiangzhao Meng
- Department of Clinical Microbiology, The Second Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Jingya Zhao
- Center for Hospital Infection Control, Chinese PLA Institute for Disease Control & Prevention, Academy of Military Medical Sciences, Beijing, China
| | - Changjian Zhang
- Center for Hospital Infection Control, Chinese PLA Institute for Disease Control & Prevention, Academy of Military Medical Sciences, Beijing, China
| | - Fang Wang
- Center for Hospital Infection Control, Chinese PLA Institute for Disease Control & Prevention, Academy of Military Medical Sciences, Beijing, China
| | - Yulong Zhang
- Center for Hospital Infection Control, Chinese PLA Institute for Disease Control & Prevention, Academy of Military Medical Sciences, Beijing, China
| | - Mengqiang Zhang
- Center for Hospital Infection Control, Chinese PLA Institute for Disease Control & Prevention, Academy of Military Medical Sciences, Beijing, China
| | - Li Han
- Center for Hospital Infection Control, Chinese PLA Institute for Disease Control & Prevention, Academy of Military Medical Sciences, Beijing, China
- * E-mail:
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Vandecandelaere I, Depuydt P, Nelis HJ, Coenye T. Protease production by Staphylococcus epidermidis and its effect on Staphylococcus aureus biofilms. Pathog Dis 2014; 70:321-31. [PMID: 24436195 DOI: 10.1111/2049-632x.12133] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 01/03/2014] [Accepted: 01/04/2014] [Indexed: 12/31/2022] Open
Abstract
Due to the resistance of Staphylococcus aureus to several antibiotics, treatment of S. aureus infections is often difficult. As an alternative to conventional antibiotics, the field of bacterial interference is investigated. Staphylococcus epidermidis produces a serine protease (Esp) which inhibits S. aureus biofilm formation and which degrades S. aureus biofilms. In this study, we investigated the protease production of 114 S. epidermidis isolates, obtained from biofilms on endotracheal tubes (ET). Most of the S. epidermidis isolates secreted a mixture of serine, cysteine and metalloproteases. We found a link between high protease production by S. epidermidis and the absence of S. aureus in ET biofilms obtained from the same patient. Treating S. aureus biofilms with the supernatant (SN) of the most active protease producing S. epidermidis isolates resulted in a significant biomass decrease compared to untreated controls, while the number of metabolically active cells was not affected. The effect on the biofilm biomass was mainly due to serine proteases. Staphylococcus aureus biofilms treated with the SN of protease producing S. epidermidis were thinner with almost no extracellular matrix. An increased survival of Caenorhabditis elegans, infected with S. aureus Mu50, was observed when the SN of protease positive S. epidermidis was added.
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Hu J, Ma XX, Tian Y, Pang L, Cui LZ, Shang H. Reduced vancomycin susceptibility found in methicillin-resistant and methicillin-sensitive Staphylococcus aureus clinical isolates in Northeast China. PLoS One 2013; 8:e73300. [PMID: 24069184 PMCID: PMC3772004 DOI: 10.1371/journal.pone.0073300] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Accepted: 07/18/2013] [Indexed: 11/18/2022] Open
Abstract
Background Strains of Staphylococcus aureus with an intermediate level of resistance to vancomycin (vancomycin-intermediate S. aureus, or VISA) or which contain subpopulations of mixed susceptibility (heterogeneous VISA, or hVISA) have been reported worldwide. However, the prevalence of VISA and hVISA infections in Northeast China is unknown. From 2007 through 2010, we surveyed the vancomycin susceptibility of methicillin-resistant and methicillin-sensitive S. aureus (MRSA and MSSA, respectively) clinical isolates in Northeast China. Methods S. aureus clinical isolates (369 MRSA and 388 MSSA) were screened for hVISA and VISA on brain heart infusion agar containing 3 μg/mL vancomycin, and their identity confirmed using a modified population analysis profile-area under the curve method and broth microdilution. All hVISA and VISA isolates were characterized genotypically and phenotypically. Results Ten percent and 0.5 percent of the isolates were hVISA and VISA, respectively. The proportion of hVISA among MSSA isolates for the entire study period was 4.1%, but increased significantly year-by-year, from 1.2% in 2007 to 7.2% in 2010. The predominant sources of hVISA and VISA isolates were sputum (56.3%), pus (18.8%), and blood (8.8%). Molecular typing of hVISA and VISA strains revealed that, taken together, 80% contained the accessory gene regulator (agr) group II, and of these, 85.7% of the MR-hVISA and MR-VISA strains were staphylococcal cassette chromosome mec (SCCmec) type II. The adherence ability of all hVISA and VISA strains was reduced compared with that of vancomycin-susceptible strains, shown by biofilm assay. Conclusions The percentage of hVISA strains was high and increased each year. The proportion of hVISA among MSSA specifically also increased significantly each year. In isolates collected from diverse infection sites, hVISA and VISA strains were found predominantly in sputum, pus, and blood, in descending order. Testing for vancomycin susceptibility should include both MRSA and MSSA isolates collected from different clinical sites.
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Affiliation(s)
- Jian Hu
- Department of Medical Microbiology and Parasitology, College of Basic Medical Sciences, China Medical University, Shenyang, People's Republic of China
- Department of Clinical Laboratory, Yixing Hospital of Traditional Chinese Medicine, Yixing, Jiangsu, People's Republic of China
| | - Xiao Xue Ma
- Department of Medical Microbiology and Parasitology, College of Basic Medical Sciences, China Medical University, Shenyang, People's Republic of China
| | - Yuan Tian
- Department of Medical Microbiology and Parasitology, College of Basic Medical Sciences, China Medical University, Shenyang, People's Republic of China
| | - Long Pang
- Department of Medical Microbiology and Parasitology, College of Basic Medical Sciences, China Medical University, Shenyang, People's Republic of China
| | - Long Zhu Cui
- Research Center for Anti-infectious Drugs, Kitasato University, Sagamihara, Kanagawa, Japan
| | - Hong Shang
- Department of Clinical Laboratory, First Affiliated Hospital of China Medical University, Shenyang, People's Republic of China
- * E-mail:
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Characterization of Tn5801.Sag, a variant of Staphylococcus aureus Tn916 family transposon Tn5801 that is widespread in clinical isolates of Streptococcus agalactiae. Antimicrob Agents Chemother 2013; 57:4570-4. [PMID: 23817370 DOI: 10.1128/aac.00521-13] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Tn5801, originally detected in Staphylococcus aureus Mu50, is a Tn916 family element in which a unique int gene (int5801) replaces the int and xis genes in Tn916 (int916 and xis916). Among 62 tet(M)-positive tetracycline-resistant Streptococcus agalactiae isolates, 43 harbored Tn916, whereas 19 harbored a Tn5801-like element (Tn5801.Sag, ∼20.6 kb). Tn5801.Sag was characterized (PCR mapping, partial sequencing, and chromosomal integration) and compared to other Tn5801-like elements. Similar to Tn5801 from S. aureus Mu50, tested in parallel, Tn5801.Sag was unable to undergo circularization and conjugal transfer.
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