Dataset Information

Genome-wide analysis of the regulatory function mediated by the small regulatory psm-mec RNA of methicillin-resistant Staphylococcus aureus

ABSTRACT: Several methicillin resistance (SCCmec) clusters characteristic of hospital-associated methicillin-resistant Staphylococcus aureus (MRSA) strains harbor the psm-mec locus. In addition to encoding the cytolysin, phenol-soluble modulin (PSM) mec, this locus has been attributed gene regulatory functions. Here we employed genome-wide transcriptional profiling to define the regulatory function of the psm-mec locus. The immune evasion factor protein A emerged as the primary conserved and strongly regulated target of psm-mec, an effect we show is mediated by the psm-mec RNA. Furthermore, the psm-mec locus exerted regulatory effects that were more moderate in extent and possibly mediated by the PSM-mec peptide. For example, expression of PSM-mec limited expression of mecA, thereby decreasing methicillin resistance. Our study shows that the psm-mec locus has a rare dual regulatory RNA and encoded cytolysin function, both with the potential to enhance MRSA virulence. Furthermore, our findings reveal a specific mechanism underscoring the recently emerging concept that S. aureus strains balance pronounced virulence and high expression of antibiotic resistance.

ORGANISM(S): Coxiella burnetii Chlamydia trachomatis Yersinia pestis Streptococcus pyogenes Borreliella burgdorferi Staphylococcus aureus

PROVIDER: GSE51366 | GEO | 2017/08/29

SECONDARY ACCESSION(S): PRJNA222833

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Approximatively 75% of the genome of S. aureus (“core” genome) are highly conserved between strains, whereas the remaining 25% (“accessory” genome) are composed of variable regions that are mostly composed of mobile genetic elements (MGE), containing virulence and resistance genes. We have developed a composite DNA-microarray (StaphVar Array) which selectively targets 403 genes located on the accessory or core variable genome. Target genes encode antimicrobial resistance factors (35 %), virulence factors (28 %) and adhesins (31%). This microarray was validated with reference strains and used to characterize the genomic DNA of 13 community-acquired methicillin resistant S. aureus (CA-MRSA) strains representative of all the Multilocus Sequence Types (STs) described to date in Belgium. Analysis of gene content of 8 reference strains by the StaphVar Array matched 96 to 99% of the theoretical results. Analysis of CA-MRSA strains showed that 54.4 % of the genes tested were strain-dependent. Strains presented specific exotoxin, enterotoxin, cytolysin and adhesin gene profile by multi-locus sequence typing (MLST) lineage. One exception to these “lineage-specific” gene profile was the variable presence of the Arginin Catabolic Mobile Element (ACME, characteristic of the USA300 clone) within ST8 strains. In conclusion, this novel StaphVar array enables characterization of more than 400 variable resistance and virulence determinants in S. aureus strains. CA-MRSA strains from Belgium displayed extensive diversity in virulence and resistance profile. The presence of the USA 300 clone in our country was confirmed. Although mainly located on MGE, association of virulence genes were highly conserved within strains of the same MLST lineage. CGH microarray was performed on 13 epidemiologically distinct clinical isolates of methicillin resistant S. aureus. S. aureus labeled genomic DNA were hybridized to StaphVar arrays containing 1326 60mer oligonucleotide probes (Eurogentec, Belgium).

Dataset Information

Genome-wide analysis of the regulatory function mediated by the small regulatory psm-mec RNA of methicillin-resistant Staphylococcus aureus

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure