Genome analysis of Staphylococcus aureus ST291, a double locus variant of ST398, reveals a distinct genetic lineage.
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ABSTRACT:
SUBMITTER: Stegger M
PROVIDER: S-EPMC3660392 | biostudies-literature | 2013
REPOSITORIES: biostudies-literature
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Genome analysis of Staphylococcus aureus ST291, a double locus variant of ST398, reveals a distinct genetic lineage.
Stegger Marc M Aziz Maliha M Chroboczek Tomasz T Price Lance B LB Ronco Troels T Kiil Kristoffer K Skov Robert L RL Laurent Frederic F Andersen Paal S PS
PloS one 20130521 5
Staphylococcus aureus ST291 has been reported as a homologue recombinant double locus variant of the livestock associated S. aureus ST398. However, whole genome sequencing show that ST291 is a unique genetic lineage with highly variable content within its accessory genome compared to both human and livestock associated genome sequenced CC398s. ...[more]
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Project description:Novel Staphylococcus aureus clones continue to emerge that cause infections in otherwise healthy people. One example is the sequence type (ST) 398 lineage, which we show here is increasing in importance as a significant cause of community-associated (CA) human infections in China. We have a profound lack of understanding about what determines the considerable virulence potential of such newly emerging clones. Information about the contribution to virulence of the more recently discovered ESAT-6 secretion system (ESS) has remained particularly scarce. The Chinese ST398 isolates exhibited significantly increased expression of ESS genes as compared to predominant hospital-associated clones, which we found is likely due to increased expression of the accessory gene regulator (Agr) system and control of ESS by Agr. Importantly, deletion of essB in ST398 resulted in significantly reduced resistance to neutrophil killing and decreased virulence in murine skin and blood infection models. Our results demonstrate a key function of ESS in promoting virulence and mechanisms of resistance to innate host defense in an important emerging CA-S. aureus lineage. They suggest that ESS has a so far underestimated role in promoting aggressive virulence and epidemiological success of S. aureus.
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