Mutation of sarA in Staphylococcus aureus Limits Biofilm Formation

Abstract

ABSTRACT Mutation of sarA resulted in a reduced capacity to form a biofilm in six of the eight Staphylococcus aureus strains we tested (UAMS-1, UAMS-601, SA113, SC-01, S6C, and DB). The exceptions were Newman, which formed a poor biofilm under all conditions, and RN6390, which consistently formed a biofilm only after mutation of agr . Mutation of agr in other strains had little impact on biofilm formation. In every strain other than Newman, including RN6390, simultaneous mutation of sarA and agr resulted in a phenotype like that observed with the sarA mutants. Complementation studies using a sarA clone confirmed that the defect in biofilm formation was due to the sarA mutation.