In vitro evaluation of CENTA, a new beta-lactamase-susceptible chromogenic cephalosporin reagent.

CENTA is a newly synthesized, beta-lactamase-labile, chromogenic cephalosporin reagent which changes color from light yellow (lambda maximum ca. 340 nm) to chrome yellow (lambda maximum ca. 405 nm) concomitant with hydrolysis of the beta-lactam ring. This compound offers promise as a diagnostic reagent comparable to other chromogens (PADAC and nitrocefin) for the early detection of beta-lactamase-producing clinical isolates, while retaining some antimicrobial effect against Escherichia coli, Klebsiella spp., Proteus mirabilis, Staphylococcus aureus, and non-enterococcal Streptococcus spp. CENTA is relatively unaffected by commonly used microbiological media and human serum.