Premium
Preparation and kinetic studies of immobilised yeast cytochrome c peroxidase
Author(s) -
Cooper JM,
McNeil CJ,
Bannister JV
Publication year - 1991
Publication title -
biotechnology and applied biochemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.468
H-Index - 70
eISSN - 1470-8744
pISSN - 0885-4513
DOI - 10.1111/j.1470-8744.1991.tb00169.x
Subject(s) - chemistry , peroxidase , enzyme , cytochrome c peroxidase , yeast , kinetics , potassium ferrocyanide , ferrocyanide , enzyme kinetics , electron acceptor , nuclear chemistry , chromatography , stereochemistry , organic chemistry , biochemistry , active site , physics , electrode , quantum mechanics
Yeast cytochrome c peroxidase (CcP) was purified from baker's yeast and immobilised onto a nylon membrane. The kinetics of the soluble and immobilised forms of the enzyme were investigated for the catalysed oxidation of potassium ferrocyanide in the presence of H2O2 and m‐chloroperoxybenzoic acid. The pH dependence of the two forms of the enzyme differed. Although both the soluble and the immobilised enzymes showed optimal activity at pH 6.2, a different kinetic behaviour was demonstrated. Both forms of the enzyme showed similar activity toward H2O2, although when m‐chloroperoxybenzoic acid was replaced as the electron acceptor, the immobilised form of the enzyme had a reduced turnover number and an increased Km. The activation energy of immobilised CcP was greater in the presence of both H2O2 [16.6 kJ mol‐1] and m‐chloroperoxybenzoic acid [37.9 kJ mol‐1] than for soluble CcP [11.4 and 23.4 kJ mol‐1, respectively]. The activities of both soluble and immobilised CcP were greatly reduced above 45 degrees C, although at higher temperatures the immobilised enzyme retained a relatively greater percentage of its maximum activity.