Stress cellulaire et induction de la β-lactamase BlaP chez Bacillus licheniformis

In presence of β-lactam antibiotic in its environment, B. licheniformis produces the β-lactamase BlaP, an enzyme hydrolyzing β-lactam antibiotic, conferring on the bacteria phenotypic resistance. To induce BlaP, two conditions must be fulfilled. The first one is the acylation of the membrane receptor BlaR1 by the antibiotic. The second one is a cellular stress due to the presence of the antibiotic which acylate PBP1. The nature of this signal remains unknown. In this study we postulate that the extracytoplasmic function sigma factors (ECFs) σM and σX act together with the stringent response as a secondary and redundant layer of stress upon which the BlaP induction pathway relies.Etude de l'induction de la β-lactamase BlaP chez Bacillus licheniformi