Ampicillin resistance in Neisseria denitrificans: studies on ampicillin-sensitive enzymes

Abstract

The β-lactam sensitivities of enzymes involved in peptidoglycan synthesis were examined in two strains of Neisseria 'enitrificans having widely disparate degrees of ampicillin sensitivity. One strain of N. denitrificans was 400 times more resistant) ampicillin than the other; the former is known to have altered pencillin-binding proteins. No differences in the levels of ensitivities of total peptidoglycan synthesis as measured by the incorporation of glutamate into peptidoglycan, or of D-alanine arboxypeptidase, were observed between the two strains. However, the rate of glutamate incorporation into peptidoglycan by garithmic growth phase cells was somewhat less for the ampicillin-resistant cells than for the parent cells.