title: Arylamidase of Cephalosporium acremonium and its specificity for cephalosporin C.
abstract: Three aggregational forms of arylamidase are produced by Cephalosporium acremonium. The exocellular enzyme, with an approximate molecular weight of 60,000, was purified 300-fold by diethylaminoethyl cellulose chromatography, gel filtration, and gel electrophoresis. With l-leucyl-beta-naphthylamide as the substrate, the K(m) is 4.2 x 10(-4)m; the optimum pH, 7.7; and the temperature optimum, 35 C. The enzymatic hydrolysis of l-leucyl-beta-naphthylamide is inhibited by a number of cephalosporins, whereas a variety of penicillins show no effect. Alternatively, the enzyme specifically catalyzes the beta-lactam hydrolysis of a number of cephalosporins; a number of penicillins are resistant. The K(m) for cephalosporin C is 9.09 x 10(-4)m.
mesh_terms: D000164:Acremonium / Q000201:enzymology* / Q000378:metabolism; D000577:Amides; D000581:Amidohydrolases / Q000037:antagonists & inhibitors / Q000302:isolation & purification; D002247:Carbon Isotopes; D002511:Cephalosporins / Q000494:pharmacology*; D002850:Chromatography, Gel; D002854:Chromatography, Paper; D003470:Culture Media; D004586:Electrophoresis; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007700:Kinetics; D008970:Molecular Weight; D009281:Naphthalenes; D010406:Penicillins / Q000494:pharmacology; D013053:Spectrophotometry; D013696:Temperature; D014466:Ultraviolet Rays
chemical_list: D000577:Amides; D002247:Carbon Isotopes; D002511:Cephalosporins; D003470:Culture Media; D009281:Naphthalenes; D010406:Penicillins; D000581:Amidohydrolases