Open AccessProperties of D ‐amino‐acid oxidase from Rhodotorula gracilis
Author(s) -
PILONE SIMONETTA Mirella,
POLLEGIONI Loredano,
CASALIN Paola,
CURTI Bruno,
RONCHI Severino
Publication year - 1989
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1989.tb14634.x
Subject(s) - flavoprotein , flavin group , d amino acid oxidase , biochemistry , chemistry , flavin adenine dinucleotide , yeast , amino acid , oxidase test , enzyme , stereochemistry , cofactor
The flavoprotein D ‐amino‐acid oxidase was purified to homogeneity from the yeast Rhodotorula gracilis by a highly reproducible procedure. The amino acid composition of the protein was determined; the protein monomer had a molecular mass of 39 kDa and contained one molecule of FAD. The ratio between A 274 / A 455 was about 8.2. D ‐Amino‐acid oxidase from yeast showed typical flavin spectral perturbations on binding of the competitive inhibitor benzoate and was reduced by D ‐alanine under anaerobiosis. The enzyme reacted readily with sulfite to form a covalent reversible adduct and stabilized the red anionic form of the flavin semiquinone on photoreduction in the presence of 5‐deazariboflavin; the 3,4‐dihydro‐FAD from was not detectable after reduction with sodium borohydride. Thus D ‐amino‐acid oxidase from yeast exhibited most of the general properties of the dehydrogenase/oxidase class of flavoproteins; at the same time, the enzyme showed some peculiar features with respect to the same protein from pig kidney.