Unknown,Transcriptomics,Genomics,Proteomics

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Regulatory role of SrrAB two-component system in Staphylococcus epidermidis growth and biofilm formation

ABSTRACT: Biofilm formation is considered the most important factor involved in pathogenicity of Staphylococcus epidermidis.We investigated the role of two-component signal transduction system (TCS) srrAB, which was up-regulated under micro-aerobic condition, in the growth and biofilm formation of S. epidermidis.AsrrA-deficient mutant (M-bM-^HM-^FsrrA) derived from S. epidermidis1457 (SE1457), exhibited dramatic reduction in growth and biofilm formation underboth aerobic and micro-aerobic conditions, and more sensitive to several different types of antimicrobial agents, H2O2 and SDS. In New Zealand Rabbit model of S. epidermidis biofilm infection, M-bM-^HM-^FsrrA hardly formed biofilm compared to that of SE1457. Phenotypic alteration was restored to the wide-type levelwhen srrAB were complemented into M-bM-^HM-^FsrrA. Further study found that the initial adherence capacity and production of polysaccharide intercellular adhesion (PIA) in M-bM-^HM-^FsrrA were decreased, while extracellular DNA (eDNA) was increased. Transcriptional Analysisby qRT-PCR demonstrated that expression level of icaRin M-bM-^HM-^FsrrA was up-regulated compared to that of SE1457 under aerobic condition, while down-regulated under micro-aerobic condition;icaA and altE were down-regulated under both conditions. Expression of genes involved in respiratory metabolism, such as qoxB(quinol oxidase polypeptide II), ctaA(heme A synthase), and pfl(pyruvate formatelyase), etc. were down-regulated in M-bM-^HM-^FsrrAunder both conditions. Electrophoretic mobility shift assay (EMSA) revealed that phosphorylated SrrA bound to the promoter regions of icaR, icaA, atlE, qoxB,ctaA, andpflB just like binding its own promoter region srr. Taken together, our results demonstrate that srrAB may provide a mechanistic link between respiratory metabolism, environmental signals, and regulation of biofilm formation in S. epidermidis. Microarrays covering different S. epidermidis genomes were used to assess the impact of the two component system srrAB on growth and biofilm formation, by comparing WT with srrA mutant transcriptomes

ORGANISM(S): Staphylococcus epidermidis

SUBMITTER: FRANCOIS Patrice

PROVIDER: E-GEOD-47101 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Staphylococcus epidermidis SrrAB regulates bacterial growth and biofilm formation differently under oxic and microaerobic conditions.

Wu Youcong Y Wu Yang Y Zhu Tao T Han Haiyan H Liu Huayong H Xu Tao T Francois Patrice P Fischer Adrien A Bai Li L Götz Friedrich F Qu Di D

Journal of bacteriology 20141117 3

SrrAB expression in Staphylococcus epidermidis strain 1457 (SE1457) was upregulated during a shift from oxic to microaerobic conditions. An srrA deletion (ΔsrrA) mutant was constructed for studying the regulatory function of SrrAB. The deletion resulted in retarded growth and abolished biofilm formation both in vitro and in vivo and under both oxic and microaerobic conditions. Associated with the reduced biofilm formation, the ΔsrrA mutant produced much less polysaccharide intercellular adhesion ...[more]

PMID: 25404696

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Dataset Information

Regulatory role of SrrAB two-component system in Staphylococcus epidermidis growth and biofilm formation

Publications

Staphylococcus epidermidis SrrAB regulates bacterial growth and biofilm formation differently under oxic and microaerobic conditions.

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