Structural and functional insights into Saccharomyces cerevisiae riboflavin biosynthesis reductase RIB7.

ABSTRACT: Saccharomyces cerevisiae RIB7 (ScRIB7) is a potent target for anti-fungal agents because of its involvement in the riboflavin biosynthesis pathway as a NADPH-dependent reductase. However, the catalytic mechanism of riboflavin biosynthesis reductase (RBSRs) is controversial, and enzyme structure information is still lacking in eukaryotes. Here we report the crystal structure of Saccharomyces cerevisiae RIB7 at 2.10 Å resolution and its complex with NADPH at 2.35 Å resolution. ScRIB7 exists as a stable homodimer, and each subunit consists of nine central β-sheets flanked by five helices, resembling the structure of RIB7 homologues. A conserved G(76)-X-G(78)-Xn-G(181)-G(182) motif is present at the NADPH pyrophosphate group binding site. Activity assays confirmed the necessity of Thr79, Asp83

SUBMITTER: Lv Z 

PROVIDER: S-EPMC3631187 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature