[Determination of lysine amidase and alpha-aminocaprolactam hydrolase activities in cell-free extracts of Cryptococcus sp].

he methods for detecting two activities, i. e. lysine amidase and alpha-aminocaprolactam hydrolase ones, in crude extracts of Cryptococcus sp. are described. The method for registering lysine amidase activity is based on the ability of Cu(II) complex to absorb at 230 nm. The products of lysine and alpha-aminocaprolactam interactions with o-phthalaldehyde in the presence of mercaptoethanol possess different molar absorption at 340 nm. This fact was used for detecting alpha-aminocaprolactam hydrolase activity. The main merit of the methods is the possibility to register the data on the course of the reaction without preliminary chromatographic separation of the reaction products and reactants. The methods proposed do not require expensive enzymes, such as lysine decarboxylase and lysine-alpha-ketoglutarate-epsilon-aminotransferase, which are used for the quantitative estimation of lysine.