Partial crypticity of penicillin-binding protein 1b in purified cell envelopes ofEscherichia coli

Abstract

InEscherichia coli, penicillin-binding protein 1b (pbp 1b) is one of the critical proteins in the biosynthesis of the murein sacculus. In this communication we present evidence indicating that pbp 1b is unusually resistant to inactivation by n-butanol and that, under the standard conditions used in pbp-labeling experiments, a considerable fraction of the total pbp 1b in the cell envelope remains inaccessible to at least some β-lactam antibiotics.