Mercuration of vanillyl‐alcohol oxidase from Penicillium simplicissimum generates inactive dimers

FEBS Letters

Mattevi, Andrea²  van Berkel, Willem J.H¹  Fraaije, Marco W¹ 

[1] Department of Biochemistry, Argicultural University, Dreijenlaan 3, 6703 HA Wageningen, The Netherlands;Department of Genetics and Microbiology, University of Pavia, via Abbiategrasso 207, 27100 Pavia, Italy

关键词: Chemical modification;    Flavoprotein;    Heavy atom derivative;    Quaternary structure;    Vanillyl-alcohol oxidase;    Penicillium simplicissimum;   

DOI  :  10.1016/S0014-5793(96)01494-9

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Vanillyl-alcohol oxidase (EC 1.1.3.7) from Penicillium simplicissimum was modified with p-mercuribenzoate. One cysteine residue reacts rapidly without loss of enzyme activity. Three sulfhydryl groups then react in an ‘all or none process’ involving enzyme inactivation and dissociation of the octamer into dimers. The inactivation reaction is slowed down in the presence of the competitive inhibitor isoeugenol and fully reversible by treatment of the modified enzyme with dithiothreitol. Vanillyl-alcohol oxidase is more rapidly inactivated at low enzyme concentrations and protected from mercuration by antichaotropic salts. It is proposed that subunit dissociation accounts for the observed sensitivity of vanillyl-alcohol oxidase crystals towards mercury compounds.

【 授权许可】

Unknown