ABSTRACT
Abstract INTRODUCTION: Methicillin-resistant Staphylococcus aureus (MRSA) is a nosocomial pathogen in community settings. MRSA colonized individuals may contribute to its dissemination; the risk of MRSA infection is increased in human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) patients, although the prevalence of colonization in this group is not well established. The present study addressed this issue by characterizing MRSA isolates from HIV/AIDS patients and their healthcare providers (HCPs) to determine whether transmission occurred between these two populations. METHODS: A total of 24 MRSA isolates from HIV-infected patients and five from HCPs were collected between August 2011 and May 2013. Susceptibility to currently available antimicrobials was determined. Epidemiological typing was carried out by pulsed-field gel electrophoresis, multilocus sequence typing, and Staphylococcus cassette chromosome (SCCmec) typing. The presence of heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA) and heterogeneous daptomycin-resistant Staphylococcus aureus (hDRSA) was confirmed by population analysis profile. Isolates characterized in this study were also compared to isolates from 2009 obtained from patients at the same hospital. RESULTS: A variety of lineages were found among patients, including ST5-SCCmecII and ST30-SCCmecIV. Two isolates were Panton-Valentine leukocidin-positive, and hVISA and hDRSA were detected. MRSA isolates from two HCPs were not related to those from HIV/AIDS patients, but clustered with archived MRSA from 2009 with no known relationship to the current study population. CONCLUSIONS: ST105-SCCmecII clones that colonized professionals in 2011 and 2012 were already circulating among patients in 2009, but there is no evidence that these clones spread to or between HIV/AIDS patients up to the 7th day of their hospitalization.
Subject(s)
Humans , Staphylococcal Infections , HIV Infections/microbiology , Cross Infection/transmission , Infectious Disease Transmission, Professional-to-Patient/statistics & numerical data , Methicillin-Resistant Staphylococcus aureus/genetics , Anti-Bacterial Agents/pharmacology , Staphylococcal Infections/microbiology , Microbial Sensitivity Tests , Cross Infection/microbiology , Bacterial Typing Techniques , Electrophoresis, Gel, Pulsed-Field , Molecular Epidemiology , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Multilocus Sequence Typing , Tertiary Care CentersABSTRACT
In this study, we investigated the presence of plasmid-mediated quinolone resistance (PMQR) genes among 101 ciprofloxacin-resistant urinary Escherichia coli isolates and searched for mutations in the quinolone-resistance-determining regions (QRDRs) of the DNA gyrase and topoisomerase IV genes in PMQR-carrying isolates. Eight isolates harboured the qnr and aac(6')-Ib-cr genes (3 qnrS1, 1 qnrB19 and 4 aac(6')-Ib-cr). A mutational analysis of the QRDRs in qnr and aac(6')-Ib-cr-positive isolates revealed mutations in gyrA, parC and parE that might be associated with high levels of resistance to quinolones. No mutation was detected in gyrB. Rare gyrA, parC and parE mutations were detected outside of the QRDRs. This is the first report of qnrB19, qnrS1 and aac(6')-Ib-cr -carrying E. coli isolates in Brazil.
Subject(s)
Female , Humans , Acetyltransferases/genetics , Anti-Bacterial Agents/pharmacology , Ciprofloxacin/pharmacology , Drug Resistance, Multiple, Bacterial/genetics , Escherichia coli Proteins/genetics , Escherichia coli/genetics , DNA Gyrase , DNA Topoisomerase IV , Electrophoresis, Gel, Pulsed-Field , Escherichia coli/drug effects , Microbial Sensitivity Tests , Mutation , Quinolones/pharmacologyABSTRACT
Mycoplasma sinoviae is a major pathogen of poultry causing synovitis and respiratory infection. M. synoviae hemagglutinin (VlhA) is a lipoprotein encoded by related multigene families that appear to have arisen by horizontal gene transfer. It is an abundant immunodominant surface protein involved in host-parasite interaction mediating binding to host erythrocytes. Herein, we have performed in silico analysis of the vlhA gene product from the Mycoplasma synoviae 53 strain and compared it to the VlhA protein of M. synoviae WUV1853 strain. The VlhA of the M. synoviae 53 strain possesses 569 amino acids and showed 85 percent identity with the VlhA protein of the M. synoviae WUV1853 strain. Further, a signal peptide was identified from amino acid M1 to D28 and a cleavage site between D28 and Q29, both located in the N-terminal domain of the molecule. Additionally, an insertion of PAPT amino acids was observed between T30-P35 and a deletion of the amino acids GTPGNP within the PRR region of the VlhA from the M. synoviae 53 strain, which may be related to its reduced virulence. Finally, we have identified 17 B cell epitopes and 22 T cells epitopes within the VlhA from the M. synoviae 53 strain. The B cell epitope S263-D277 and the T cell epitopes N45-N54 and G58-N67 showed 100 percent and 87-100 percent identity, respectively, with regions of VlhA protein of tested Mycoplasma synoviae and Mycoplasma galisepticum strains. Thus, these peptides represent new candidate molecules for the development of efficient diagnostic assays and new subunit vaccines.