title: Human skeletal muscle contains two major aminopeptidases: an anion-activated aminopeptidase B and an aminopeptidase M-like enzyme.
abstract: Two major aminopeptidases, an aminopeptidase B and an aminopeptidase M-like enzyme, were purified from human skeletal muscle by DEAE-cellulose, HPLC gel filtration, and hydroxyapatite column chromatographies. The purified aminopeptidase B exhibits a molecular weight of 76,000 under both native and denaturing conditions. The activity of the aminopeptidase B is regulated by C1 ions and other anions in vitro. On the other hand, the aminopeptidase M-like enzyme is a monomeric protein having a molecular weight of 96,000. It is capable of significantly cleaving Phe-, Leu-, Arg-, and Ala-aminoacyl bonds in the presence of 2-mercaptoethanol. The pH optima for both enzymes are around 7.0, and bestatin is an effective inhibitor of both enzymes.
mesh_terms: D000596:Amino Acids / Q000378:metabolism; D000626:Aminopeptidases / Q000037:antagonists & inhibitors / Q000302:isolation & purification / Q000378:metabolism*; D000838:Anions; D018826:CD13 Antigens; D002712:Chlorides / Q000494:pharmacology; D002848:Chromatography, DEAE-Cellulose; D003374:Coumarins / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D004789:Enzyme Activation / Q000187:drug effects; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008623:Mercaptoethanol / Q000494:pharmacology; D008970:Molecular Weight; D009132:Muscles / Q000201:enzymology*; D013379:Substrate Specificity
chemical_list: D000596:Amino Acids; D000838:Anions; D002712:Chlorides; D003374:Coumarins; D008623:Mercaptoethanol; D000626:Aminopeptidases; D018826:CD13 Antigens; C019721:aminopeptidase B