Synthesis of amino acid cofactor in cysteine dioxygenase is regulated by substrate and represents a novel post-translational regulation of activity.

ABSTRACT: Cysteine dioxygenase (CDO) catalyzes the conversion of cysteine to cysteinesulfinic acid and is important in the regulation of intracellular cysteine levels in mammals and in the provision of oxidized cysteine metabolites such as sulfate and taurine. Several crystal structure studies of mammalian CDO have shown that there is a cross-linked cofactor present in the active site of the enzyme. The cofactor consists of a thioether bond between the gamma-sulfur of residue cysteine 93 and the aromatic side chain of residue tyrosine 157. The exact requirements for cofactor synthesis and the contribution of the cofactor to the catalytic activity of the enzyme have yet to be fully described. In this study, therefore, we explored the factors necessary for cofactor biogenesis in vitro and in vivo and

SUBMITTER: Dominy JE 

PROVIDER: S-EPMC2335356 | biostudies-literature | 2008 May

REPOSITORIES: biostudies-literature