Phosphines are ribonucleotide reductase reductants that act via C-terminal cysteines similar to thioredoxins and glutaredoxins.

ABSTRACT: Ribonucleotide reductases (RNRs) catalyze the formation of 2'-deoxyribonucleotides. Each polypeptide of the large subunit of eukaryotic RNRs contains two redox-active cysteine pairs, one in the active site and the other at the C-terminus. In each catalytic cycle, the active-site disulfide is reduced by the C-terminal cysteine pair, which in turn is reduced by thioredoxins or glutaredoxins. Dithiols such as DTT are used in RNR studies instead of the thioredoxin or glutaredoxin systems. DTT can directly reduce the disulfide in the active site and does not require the C-terminal cysteines for RNR activity. Here we demonstrate that the phosphines tris(2-carboxyethyl)phosphine (TCEP) and tris(3-hydroxypropyl)phosphine (THP) are efficient non-thiol RNR reductants, but in contrast to the dithiols

SUBMITTER: Domkin V 

PROVIDER: S-EPMC4078304 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature