Another layer of complexity in Staphylococcus aureus methionine biosynthesis control: unusual RNase III-driven T-box riboswitch cleavage determines met operon mRNA stability and decay.

In Staphylococcus aureus, de novo methionine biosynthesis is regulated by a unique hierarchical pathway involving stringent-response controlled CodY repression in combination with a T-box riboswitch and RNA decay. The T-box riboswitch residing in the 5' untranslated region (met leader RNA) of the S. aureus metICFE-mdh operon controls downstream gene transcription upon interaction with uncharged methionyl-tRNA.

A non-coding RNA from the intercellular adhesion (ica) locus of Staphylococcus epidermidis controls polysaccharide intercellular adhesion (PIA)-mediated biofilm formation.

Polysaccharide intercellular adhesin (PIA)-associated biofilm formation is mediated by the intercellular adhesin (ica) locus and represents a major pathomechanism of Staphylococcus epidermidis. Here, we report on a novel long non-coding (nc)RNA, named IcaZ, which is approximately 400 nucleotides in size. icaZ is located downstream of the ica repressor gene icaR and partially overlaps with the icaR 3' UTR.

The small non-coding RNA RsaE influences extracellular matrix composition in Staphylococcus epidermidis biofilm communities.

RsaE is a conserved small regulatory RNA (sRNA) which was previously reported to represent a riboregulator of central carbon flow and other metabolic pathways in Staphylococcus aureus and Bacillus subtilis. Here we show that RsaE contributes to extracellular (e)DNA release and biofilm-matrix switching towards polysaccharide intercellular adhesin (PIA) production in a hypervariable Staphylococcus epidermidis isolate. Transcriptome analysis through differential RNA sequencing (dRNA-seq) in combination with confocal laser scanning microscopy (CLSM) and reporter gene fusions demonstrate that S.

Antibiotic resistance profiles of coagulase-negative staphylococci in livestock environments.

Livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) have globally emerged in animal husbandry. In addition to methicillin resistance, LA-MRSA may carry a variety of novel and uncommon antimicrobial resistance genes. Occurrence of the same resistance genes in coagulase-negative staphylococci (CoNS) and S.

Genotyping of community-associated methicillin resistant Staphylococcus aureus (CA-MRSA) in a tertiary care centre in Mysore, South India: ST2371-SCCmec IV emerges as the major clone.

The burden of community-associated methicillin resistant Staphylococcus aureus (CA-MRSA) is on the rise in population and clinical settings on account of the adaptability and virulence traits of this pathogen. We characterized 45 non-duplicate CA-MRSA strains implicated mainly in skin and soft tissue infections (SSTIs) in a tertiary care hospital in Mysore, South India. All the isolates were genotyped by staphylococcal cassette chromosome mec (SCCmec) typing, staphylococcal protein A (spa) typing, accessory gene regulator (agr) typing, and multi-locus sequence typing (MLST).

Methionine biosynthesis in Staphylococcus aureus is tightly controlled by a hierarchical network involving an initiator tRNA-specific T-box riboswitch.

In line with the key role of methionine in protein biosynthesis initiation and many cellular processes most microorganisms have evolved mechanisms to synthesize methionine de novo. Here we demonstrate that, in the bacterial pathogen Staphylococcus aureus, a rare combination of stringent response-controlled CodY activity, T-box riboswitch and mRNA decay mechanisms regulate the synthesis and stability of methionine biosynthesis metICFE-mdh mRNA. In contrast to other Bacillales which employ S-box riboswitches to control methionine biosynthesis, the S.

Hypervariability of biofilm formation and oxacillin resistance in a Staphylococcus epidermidis strain causing persistent severe infection in an immunocompromised patient.

We report on a leukemic patient who suffered from a persistent, generalized, and eventually fatal Staphylococcus epidermidis infection during prolonged aplasia. Over a 6-week period, we isolated a genetically and phenotypically unstable S. epidermidis strain related to an epidemic clone associated with hospital infections worldwide.

Success through diversity - how Staphylococcus epidermidis establishes as a nosocomial pathogen.

Staphylococcus epidermidis normally is a commensal inhabitant of the healthy human skin and mucosa, but also a common nosocomial pathogen in immunocompromised patients. Living at the edge between commensalism and pathogenicity, S. epidermidis has developed interesting strategies to conquer the hospital environment as a novel ecological niche and to transform into a notorious pathogen.