Comparative genomics and DNA array-based genotyping of pandemic Staphylococcus aureus strains encoding Panton-Valentine leukocidin

Abstract

Within the last few years, methicillin-resistant Staphylococcus aureus (MRSA) strains encoding Panton-Valentine leukocidin (PVL) have emerged and spread worldwide. This epidemic can be attributed to a small number of distinct clones. The present study used a novel assay, based on multiplex linear DNA amplification and subsequent microarray hybridisation, to simultaneously detect all relevant exotoxins, antimicrobial resistance determinants and the allelic variants of agr. The genes of the staphylococcal exotoxin-like (set) locus were also included for typing purposes. This assay, together with multilocus sequence typing (MLST) and spa typing, was applied to 56 clinical isolates and reference strains representing all major pandemic PVL-MRSA lineages, as well as to phylogenetically-related strains and putative ancestors. Array hybridisation results allowed the assignment of isolates to clonal groups, which were in accordance with MLST and spa typing data. Ten distinct clonal groups of PVL-MRSA (ST1, ST5, ST8, ST22, ST30, ST59/359, ST80/583, ST88, ST93 and ST152), including 12 MLST types, were identified and analysed with regard to resistance determinants and genes coding for exotoxins. The array hybridisation data confirmed that pandemic PVL-positive strains originate from very diverse genetic backgrounds, and provided insights into the evolution of some lineages. The DNA microarray technique provides a valuable epidemiological tool for the detailed characterisation of clinical isolates and comparison of strains at a global level.

Association of Recurrent Furunculosis with Panton-Valentine Leukocidin and the Genetic Background of Staphylococcus aureus

“…The agr locus belongs to the core variable genome and is thus strictly linked to CCs (33). In agreement with the findings of other studies (22,36,39), we observed that agr-1 was linked to CC8, CC22, CC45, ST7, and ST59; agr-2 was present in CC5, CC12, CC15, and ST109; agr-3 was associated with CC1 and CC30; and agr-4 was detected in CC121.…”

Emergence of Hospital- and Community-Associated Panton-Valentine Leukocidin-Positive Methicillin-Resistant Staphylococcus aureus Genotype ST772-MRSA-V in Ireland and Detailed Investigation of an ST772-MRSA-V Cluster in a Neonatal Intensive Care Unit

“…All MRSA isolates associated with the cluster were investigated by DNA microarray analysis using the StaphyType kit (Alere Technologies GmbH, Jena, Germany) to detect 334 S. aureus gene sequences and alleles, including antimicrobial resistance genes, virulence-associated genes, and typing markers (23). The array also assigned isolates to a multilocus sequence type (ST) and/or clonal complex (CC) and SCCmec type (25).…”

“…The emergence of CA-MRSA clones was originally thought to be continent specific, but intercontinental spread of several CA-MRSA clones has been observed and new clones have also emerged (23). Recently, a PVL-positive CA-MRSA clone, ST772-MRSA-V, that is relatively multiantibiotic resistant compared to other CA-MRSA clones was identified in several countries.…”

Virulence properties of methicillin-susceptible Staphylococcus aureus food isolates encoding Panton–Valentine Leukocidin gene

“…In another study, ST152 was found to be the second most common (after ST8) clonal type among PVL-positive MRSA isolates in Austria (Krziwanek et al, 2007). In addition, Monecke et al (2007) reported a PVL-positive MRSA strain, isolated from an immigrant child from Macedonia, having ST152 clonal type and t355 spa type. Interestingly, not only PVL-positive MRSA isolates, but also PVL-positive MSSA isolates from different countries have been reported having ST152 clonal type.…”