title: Distinct behavior of beta-endorphin and corticotropin toward leucine aminopeptidase action.
abstract: Reactions of human beta-endorphin, corticotropin and their synthetic analogs with leucine aminopeptidase have been investigated. The results confirmed previous findings that beta-endorphin is resistant to the aminopeptidase action whereas corticotropin is not. Beta-endorphin-(1-5) is completely digested by the enzyme while beta-endorphin-(1-17) is resistant. In contrast, the NH2-terminal 7 residues in corticotropin are removed readily by leucine aminopeptidase. This is confirmed by the observation that human corticotropin-(7-38) is not hydrolyzed by the enzyme. This contrasting behavior of the two hormones toward leucine aminopeptidase may be related to differences in their conformational structures.
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000031:analogs & derivatives / Q000378:metabolism*; D000595:Amino Acid Sequence; D002851:Chromatography, High Pressure Liquid; D004723:Endorphins / Q000378:metabolism*; D006801:Humans; D006868:Hydrolysis; D007700:Kinetics; D007931:Leucyl Aminopeptidase / Q000378:metabolism*; D013379:Substrate Specificity; D001615:beta-Endorphin
chemical_list: D004723:Endorphins; D001615:beta-Endorphin; D000324:Adrenocorticotropic Hormone; D007931:Leucyl Aminopeptidase