A mechanism for the transfer of the carboxyl‐group from 1'‐N‐carboxybiotin to acceptor substrates by biotin‐containing enzymes

FEBS Letters

Prager, R.¹  Keech, D.B.²  Wallace, J.C.²  Goodall, G.J.² 

[1] Department of Organic Chemistry, University of Adelaide, Adelaide, SA 5000, Australia;Department of Biochemistry, University of Adelaide, Adelaide, Australia

关键词: Biotin;    Carboxylase;    Carboxyl-group transfer;    Pyruvate carboxylase;    Propionyl-CoA carboxylase;    Reaction mechanism;   

DOI  :  10.1016/0014-5793(83)81150-8

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Previous proposals for the mechanism by which biotin-dependent enzymes catalyse the transfer of the carboxyl group from 1'-N-carboxybiotin to acceptor molecules do not appear to be consistent with all of the experimental observations now available. We propose a multi-step mechanism in which (a) substrate and then carboxybiotin bind at the second partial reaction site, (b) a base positioned adjacent to the 3'-N of the carboxybiotin abstracts a proton from the 3'-N and (c) the resulting enolate ion and the acceptor substrate undergo a concerted reaction resulting in carboxyl-group transfer.

【 授权许可】

Unknown