4HA7

Structural insights into the reduction mechanism of Saccharomyces cerevisia Riboflavin Biosynthesis Reductase Rib7

Summary for 4HA7

• Entry DOI: 10.2210/pdb4ha7/pdb
• Related: 4HA9
• Descriptor: 2,5-diamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate reductase (2 entities in total)
• Functional Keywords: reductase, nadph binding, oxidoreductase
• Biological source: Saccharomyces cerevisiae (Baker's yeast)
• Total number of polymer chains: 2
• Total formula weight: 55115.20

Authors

Lv, Z.,Sun, J.,Liu, Y. (deposition date: 2012-09-25, release date: 2013-09-04, Last modification date: 2024-02-28)

Primary citation

Lv, Z.,Sun, J.,Liu, Y.
Structural and functional insights into Saccharomyces cerevisiae riboflavin biosynthesis reductase RIB7.
Plos One, 8:e61249-e61249, 2013

PubMed 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, Glu180 and Gly182 for the activity of ScRIB7. Substrate preference of ScRIB7 was altered by mutating one residue (Thr35) to a Lysine, implying that ScRIB7 Thr35 and its corresponding residue, a lysine in bacteria, are important in substrate-specific recognition.

PubMed: 23620735
DOI: 10.1371/journal.pone.0061249

Experimental method

X-RAY DIFFRACTION (2.1 Å)