Rate of ADP hydrolysis by SPS2 Sec/Cys mutant enzyme (hSPS2Cys)

Value 38 nmol/min/mg protein
Organism Human Homo sapiens
Reference Wang KT, Wang J, Li LF, Su XD. Crystal structures of catalytic intermediates of human selenophosphate synthetase 1. J Mol Biol. 2009 Jul 24 390(4):747-59PubMed ID19477186
Method Researchers determined the high-resolution crystal structure of human selenophosphate synthetase 1 (hSPS1). An unexpected reaction intermediate, with a tightly bound phosphate and ADP at the active site has been captured in the structure. An enzymatic assay revealed that hSPS1 possesses low ADP hydrolysis activity in the presence of phosphate.
Comments The human SPS2 Sec/Cys mutant enzyme (hSPS2Cys) was able to hydrolyze ADP in a manner similar to that of hSPS1. Researchers' calculated ADP hydrolysis rate for hSPS2 Cys (38 nmol min–1 mg–1 of protein) is comparable with previously reported E. coli SPS activity (83 nmol min–1 mg–1 of protein)
Entered by Uri M
ID 104534