Activity of Ceftaroline against Enterococcus faecium PBP5

Abstract

ABSTRACTThe opportunistic human pathogenEnterococcus faeciumoverproduces the low-affinity PBP5. In clinical strains, mutations in PBP5 further reduce its acylation rate by β-lactams. Previous studies have reported that ceftaroline had poor inhibitory activity against β-lactam-resistantE. faeciumstrains. In this study, we show that ceftaroline exhibits killing activity against our laboratory-derived ampicillin-resistantE. faeciummutant that overproduces a wild-type PBP5 and that ceftaroline inactivates PBP5 much faster than benzylpenicillin and faster than ceftobiprole.