Ciprofloxacin, rifampicin, chloramphenicol, tetracycline, aminoglycosides and fusidic acid resistance was significantly more common amongst CpA isolates. Multidrug resistance (MDR) was detected among 96.7% of isolates but they differed in the prevalence of specific macrolide, aminoglycoside and trimethoprim resistance genes amongst SE and SH isolates. Overall, 39.6% of MR isolates harbored NT SCCmec elements, and ACME was more common amongst MRSE and CpA isolates. Although only one ST- SCCmec type combination (ST1 with a non-typeable SCCmec NT9 ) was common to four MRSH-Hu and one MRSH-CpA, all MRSH isolates were closely related based on similar STs, SCCmec genes (V/VT or components thereof), mecA alleles and dts. Identical mecA alleles and nontypeable dru types (dts) were identified in one ST2-MRSE-IVc Hu and CpA isolate, however, all mecA alleles and 2/4 dts detected among 18 ST2-MRSE-IVc isolates were closely related, sharing >96.5% DNA sequence homology. SCCmec IV predominated among MRSE with ST2-MRSE-IVc common to both Hu (40.9%) and CpA (54.5%). Isolates were predominantly assigned to sequence types (STs) within a single clonal complex (CC2, SE, 84.8% CC1, SH, 95.2%). All methicillin-resistant (MR) isolates (33/40 SE, 20/21 SH) underwent dru and mecA allele typing. All isolates underwent antimicrobial susceptibility testing, multilocus sequence typing and DNA microarray profiling to detect antimicrobial resistance and SCCmec-associated genes. This study compares the characteristics of Staphylococcus epidermidis (SE) and Staphylococcus haemolyticus (SH) isolates from epidemiologically unrelated infections in humans (Hu) (28 SE-Hu 8 SH-Hu) and companion animals (CpA) (12 SE-CpA 13 SH-CpA). McManus, Brenda A Coleman, David C Deasy, Emily C Brennan, Gráinne I O' Connell, Brian Monecke, Stefan Ehricht, Ralf Leggett, Bernadette Leonard, Nola Shore, Anna C The highly divergent nature of SCCmec XI relative to other SCCmec elements indicates that it may have originated in another taxon.Ĭomparative Genotypes, Staphylococcal Cassette Chromosome mec ( SCCmec) Genes and Antimicrobial Resistance amongst Staphylococcus epidermidis and Staphylococcus haemolyticus Isolates from Infections in Humans and Companion Animals. aureus strains were predominantly from bovine sources. The CC130 MRSA isolates may be of animal origin as previously reported CC130 S. SCCmec XI was also identified in the second CC130 MRSA isolate by PCR and sequencing. 3 kb downstream of SCCmec XI, indicating the presence of a possible SCC remnant.
The open reading frames (ORFs) identified within SCCmec XI of M10\\/0061 exhibited 21 to 93% amino acid identity to ORFs in GenBank. The SCCmec element was almost identical to that of SCCmec type XI ( SCCmec XI) identified by the Sanger Institute in sequence type 425 bovine MRSA strain LGA251 listed on the website of the International Working Group on the Classification of Staphylococcal Cassette Chromosome Elements. Whole-genome sequencing of one isolate (M10\\/0061) revealed a 30-kb SCCmec element encoding a class E mec complex with highly divergent blaZ- mecA-mecR1- mecI, a type 8 cassette chromosome recombinase (ccr) complex consisting of ccrA1-ccrB3, an arsenic resistance operon, and flanking direct repeats (DRs). aureus using the GeneXpert real-time PCR assay. The isolates were identified as methicillin-susceptible S.
In this study, two clonal complex 130 (CC130) methicillin-resistant Staphylococcus aureus (MRSA) isolates from patients in Irish hospitals were identified that were phenotypically PBP 2a positive but lacked mecA by conventional PCR and by DNA microarray screening. Methicillin resistance in staphylococci is mediated by penicillin binding protein 2a (PBP 2a), encoded by mecA on mobile staphylococcal cassette chromosome mec ( SCCmec) elements. Detection of staphylococcal cassette chromosome mec type XI carrying highly divergent mecA, mecI, mecR1, blaZ, and ccr genes in human clinical isolates of clonal complex 130 methicillin-resistant Staphylococcus aureus.