Open AccessPhenylalanine dehydrogenase of Bacillus badius
Author(s) -
ASANO Yasuhisa,
NAKAZAWA Akiko,
ENDO Kaori,
HIBINO Yasuo,
OHMORI Muneki,
NUMAO Naganori,
KONDO Kiyosi
Publication year - 1987
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1987.tb13399.x
Subject(s) - biochemistry , isoelectric point , biology , escherichia coli , microbiology and biotechnology , enzyme , oxidative deamination , phenylalanine , chemistry , amino acid , gene
Phenylalanine dehydrogenase produced by Bacillus badius IAM 11059 was purified from the crude extract of B. badius to homogeneity, as judged by disc gel electrophoresis. The enzyme has an isoelectric point of 3.5 and a relative molecular mass, M r , of 310000–360000. The enzyme is composed of identical subunits with an M r 41000–42000. The substrate specificity of the enzyme in the oxidative deamination reaction was high for l ‐phenylalanine, but rather low in the reductive amination reaction, with phenylpyruvate, p ‐hydroxyphenylpyruvate, and 2‐oxohexanoate. The gene for the enzyme was cloned into Escherichia coli with plasmid pBR322 as a vector. The enzyme was expressed in high level in E. coli . The enzyme produced by E. coli transformant was purified to homogeneity and shown to be identical to that of B. badius IAM 11059 with respect to the specific activity, M r , subunit structure and amino acid composition.