Description of a 23.9-Kilobase Chromosomal Deletion Containing a Region Encoding fsr Genes Which Mainly Determines the Gelatinase-Negative Phenotype of Clinical Isolates of Enterococcus faecalis in Urine

Expression of virulence-related extracellular proteases, gelatinase, and serine protease of Enterococcus faecalis is regulated by a quorum-sensing system encoded by the fsr gene cluster. In this study, a 23.9-kb chromosomal deletion containing the fsr gene cluster region was found to be present in the majority (79%) of gelatinase-negative clinical isolates of E. faecalis from urine.