L-Alanine 4-nitroanilide hydrochloride

H-Ala-pNA·HCl

 

MOLECULAR BIOLOGY GRADE

 

H-Ala-pNA·HCl is a substrate for L-alanine aminopeptidase, which is an enzyme that is localized in bacterial cell walls responsible for the cleavage of L-alanine from various peptides. It is found that significant L-alanine aminopeptidase activity is specific to gram-negative microbes. Therefore H-Ala-pNA·HCl can be used in support of evidence that an organism is gram positive or gram negative. It is split by L-alanine aminopeptide into L-alanine and 4-nitroanine. The latter compound causes bacterial suspension to turn yellow.