MIKROBIOLOGISCH HERGESTELLTE ALPHA-ACETYLAMINOZIMTSAEURE-ACYLASE, VERFAHREN ZU IHRER GEWINNUNG UND IHRE VERWENDUNG.

摘要

New microbially produced alpha-acetamido- cinnamic acid acylase is characterised by the following properties (A) reacts with alpha-acetamide -cinnamic acid to form alpha-imino-beta- phenylpropionic acid or phenylpyruvic acid; (B) hydrolyses alpha-acetamido -cinnamic acid but not other alpha-acetamido carboxylic acids (e.g. alpha-acetamidoacrylic acid or N-acetylphenylalanine); (C) optimal pH 7.5 +/- 1; (D) good stability in pH range 6.9-9.4 (above 90% residual activity after 2 weeks at 4 deg.C); (E) optimal temp. 52 deg.C at pH 7.5; (F) 80% residual activity still detectable after incubation for 30 mins. at 52 deg.C; (G) inhibited by mercury cpds. (p-mercuribenzoate, HgCl2), CdCl2 and o-phenanthroline, activated by the addn. of dithiothreitol (1 mmol.); (H) mol. wt. 50000 +/-5000 Dalton; (I) consists of two equal-size subunits each of mol. wt. 26000 +/- 3000 Dalton; (J) Km for alpha-acetamidocinnamic acid as substrate is 0.45 mMol at pH 7.5.