Fluorogenic L-alanylaminopeptidase substrates derived from 6-amino-2-hetarylquinolines and 7-amino-3-hetarylcoumarins and their potential applications in diagnostic microbiology

Six novel fluorogenic enzyme substrates for detecting L-alanylaminopeptidase activity in microorganisms have been prepared and evaluated in Columbia agar media. The substrates are L-alanyl derivatives of 6-amino-2-hetarylquinolines and 7-amino-3-hetarylcoumarins. Both the quinoline and coumarin series of substrates produced fluorescence in the presence of Gram-negative microorganisms. In contrast, fluorescence generation in the presence of the Gram-positive microorganisms and yeasts was limited or absent.