A Homolog of CcpA Mediates Catabolite Control in Listeria monocytogenes but Not Carbon Source Regulation of Virulence Genes

摘要: Readily utilizable sugars down-regulate virulence gene expression in Listeria monocytogenes, which has led to the proposal that this regulation may be an aspect of global catabolite (CR). We recently demonstrated metabolic enzyme alpha-glucosidase is under CR L. monocytogenes. Here, we report cloning and characterization from monocytogenes apparent ortholog ccpA, encodes important mediator several low-G+C-content gram-positive bacteria. ccpA (ccpALm) predicted encode a 335-amino-acid protein with nearly 65% identity product Bacillus subtilis (ccpABs). Southern blot analysis probe derived ccpALm revealed single strongly hybridizing band also second much lower intensity, suggesting there other closely related sequences chromosome, as case B. subtilis. Disruption resulted inability mutant grow on glucose-containing minimal medium or increase its growth rate presence preferred sugars, it completely eliminated activity liquid medium. However, was only partially relieved solid These results suggest element carbon source Nevertheless, still hly, factor hemolysin, mutant, indicating CcpA not involved genes.