Disease relevance of msrA1

• Regulation of the expression of cell wall stress stimulon member gene msrA1 in methicillin-susceptible or -resistant Staphylococcus aureus [1].

High impact information on msrA1

• In the present study we show that msrA1 induction by oxacillin is common to all methicillin-susceptible strains studied but did not occur in two homogeneous and two heterogeneous methicillin-resistant strains [1].
• However, msrA1 was induced by vancomycin and/or D-cycloserine in methicillin-resistant strains [1].
• In complementation assays, while the msrA2 gene was unable to complement the msrA1 msrA2 double mutant for H(2)O(2) resistance, the same gene restored H(2)O(2) tolerance in the double mutant when placed under the control of the msrA1 promoter [2].
• However, msrA1 which was able to complement the oxidative stress response in msrA1 mutants could not restore the tolerance of the msrA1 msrA2 mutants to H(2)O(2) when placed under the control of the msrA2 promoter [2].
• Assessment of substrate specificity together with increased reactivity of the cell-free protein extracts of the msrA1 mutants to anti-MsrB polyclonal antibodies in Western analysis provided evidence that increased Msr activity was due to elevated synthesis of MsrB in the MsrA1 mutants [2].

Chemical compound and disease context of msrA1

• Genome-wide transcriptional profiling studies of the response of Staphylococcus aureus to cell wall-active antibiotics have led to the discovery of a cell wall stress stimulon of genes induced by these agents. msrA1, encoding methionine sulfoxide reductase, is a highly induced member gene of this stimulon [1].

Associations of msrA1 with chemical compounds

• Previously, it was reported that oxacillin treatment of S. aureus cells led to induced synthesis of MsrA1 and a mutation in msrA1 increased the susceptibility of the organism to H(2)O(2) [2].

Analytical, diagnostic and therapeutic context of msrA1

• Additionally, although the oxacillin minimum inhibitory concentration of the msrA1 mutant was comparable to that of the wild-type parent, in shaking liquid culture, the msrA1 mutant responded more efficiently to sublethal doses of oxacillin [2].

References