The signal transducer encoded by ampG is essential for induction of chromosomal AmpC beta-lactamase in <taxon tax_id="562">Escherichia coli</taxon> by beta-lactam antibiotics and 'unspecific' inducers [<cite idref="PUB00007028"/>]. The ampG protein probably acts as a permease in the beta-lactamase induction system and in peptidoglycan recycling. AmpG-related permease