The activation mechanism of human porphobilinogen synthase by 2-mercaptoethanol: intrasubunit transfer of a reserve zinc ion and coordination with three cysteines in the active center.

Abstract excerpt

Human porphobilinogen synthase [EC.4.2.1.24] is a homo-octamer enzyme. In the active center of each subunit, four cysteines are titrated with 5,5'-dithiobis(2-nitrobenzoic acid). Cys(122), Cys(124) and Cys(132) are placed near two catalytic sites, Lys(199) and Lys(252), and coordinate a zinc ion, referred to as "a proximal zinc ion", and Cys(223) is placed at the orifice of the catalytic cavity and coordinates a...

Topics

Share this publication in a Topic to start or enrich a Post.

• Share to Binding Sites
• Share to Cysteine