Penicillin-binding proteins 4 and 5 ofHaemophilus influenzaeare involved in cell wall incorporation

Abstract

Permeabilized cells of Haemophilus influenzae incorporate wall precursors into murein material in an ampicillin-sensitive reaction. In resistant transformants that contain the low antibiotic affinity penicillin-binding proteins (PBPs) 4 and 5, the sensitivity of this incorporation reaction to ampicillin is proportionally lower, suggesting a catalytic role for these proteins in wall synthesis. We conclude that, analogous to the reaction in Escherichia coli, PBPs 4 and 5 of H. influenzae have transpeptidase activity.