Reactivity of histidyl residues in d‐amino acid oxidase from Rhodotorula gracilis

FEBS Letters

Gadda, Giovanni¹  Beretta, Giovanni L.¹  Pilone, Mirella S.¹ 

[1] Department of General Physiology and Biochemistry, University of Milano, via Celoria 26, 20133 Milano, Italy

关键词: d-Amino acid oxidase;    Histidine;    Covalent modification;    Dansyl chloride;    Methyl-p-nitrobenzenesulfonate;    Rhodotorula gracilis;    DAAO;    d-amino acid oxidase;    DNS-Cl;    dansyl chloride;    MNBS;    methyl-p-nitrobenzenesulfonate;    FAD;    flavin adenine dinucleotide;   

DOI  :  10.1016/0014-5793(95)00337-9

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Incubation of d-amino acid oxidase from the yeast Rhodotorula gracilis with excess dansyl chloride at pH 6.6 and 18°C caused an irreversible inactivation of d-amino acid oxidase. Benzoate, a competitive inhibitor of the enzyme, completely protected the enzyme from inactivation. The dansylated-enzyme, isolated by gel-filtration, was in part still active while the substrate specificity was altered substantially. It was completely reduced by d-alanine in anaerobiosic conditions and did stabilize the red anion semiquinone upon photochemical reduction with EDTA. The results provide evidence for the presence of essential histidyl residue(s) in the active center of the yeast enzyme.

【 授权许可】

Unknown