Disulfide bridges are not involved in penicillin-binding protein 1b dimerization in Escherichia coli

PBP1b can be found as a dimer in Escherichia coil. Previous results suggest ed that dimerization involved the cysteine(s) in an intermolecular disulfid e bond. We show that either deletion mutants or a mutant without cysteines is fully active and still binds penicillin and that the latter can also for m dimers.