Open AccessStructures of Saccharomyces cerevisiae D‐arabinose dehydrogenase Ara1 and its complex with NADPH: implications for cofactor‐assisted substrate recognition
Author(s) -
Hu XiaoQian,
Guo PengChao,
Ma JinDi,
Li WeiFang
Publication year - 2013
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
ISSN - 1744-3091
DOI - 10.1107/s1744309113026857
Subject(s) - cofactor , saccharomyces cerevisiae , biochemistry , yeast , substrate (aquarium) , dehydrogenase , oxidoreductase , protein subunit , chemistry , binding site , stereochemistry , enzyme , nad+ kinase , biology , gene , ecology
The primary role of yeast Ara1, previously mis‐annotated as a D‐arabinose dehydrogenase, is to catalyze the reduction of a variety of toxic α,β‐dicarbonyl compounds using NADPH as a cofactor at physiological pH levels. Here, crystal structures of Ara1 in apo and NADPH‐complexed forms are presented at 2.10 and 2.00 Å resolution, respectively. Ara1 exists as a homodimer, each subunit of which adopts an (α/β) 8 ‐barrel structure and has a highly conserved cofactor‐binding pocket. Structural comparison revealed that induced fit upon NADPH binding yielded an intact active‐site pocket that recognizes the substrate. Moreover, the crystal structures combined with computational simulation defined an open substrate‐binding site to accommodate various substrates that possess a dicarbonyl group.