1YQD

Sinapyl Alcohol Dehydrogenase complexed with NADP+

1YQD の概要

• エントリーDOI: 10.2210/pdb1yqd/pdb
• 分子名称: sinapyl alcohol dehydrogenase, ZINC ION, NADP NICOTINAMIDE-ADENINE-DINUCLEOTIDE PHOSPHATE, ... (6 entities in total)
• 機能のキーワード: lignin, monolignol, oxidoreductase, zinc-dependent, plant defense, biosynthesis, substrate inhibition, medium-chain dehydrogense/reductase
• 由来する生物種: Populus tremuloides (quaking aspen)
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 80907.10

構造登録者

Bomati, E.K.,Noel, J.P. (登録日: 2005-02-01, 公開日: 2005-07-12, 最終更新日: 2024-04-03)

主引用文献

Bomati, E.K.,Noel, J.P.
Structural and Kinetic Basis for Substrate Selectivity in Populus tremuloides Sinapyl Alcohol Dehydrogenase.
Plant Cell, 17:1598-1611, 2005

PubMed Abstract: We describe the three-dimensional structure of sinapyl alcohol dehydrogenase (SAD) from Populus tremuloides (aspen), a member of the NADP(H)-dependent dehydrogenase family that catalyzes the last reductive step in the formation of monolignols. The active site topology revealed by the crystal structure substantiates kinetic results indicating that SAD maintains highest specificity for the substrate sinapaldehyde. We also report substantial substrate inhibition kinetics for the SAD-catalyzed reduction of hydroxycinnamaldehydes. Although SAD and classical cinnamyl alcohol dehydrogenases (CADs) catalyze the same reaction and share some sequence identity, the active site topology of SAD is strikingly different from that predicted for classical CADs. Kinetic analyses of wild-type SAD and several active site mutants demonstrate the complexity of defining determinants of substrate specificity in these enzymes. These results, along with a phylogenetic analysis, support the inclusion of SAD in a plant alcohol dehydrogenase subfamily that includes cinnamaldehyde and benzaldehyde dehydrogenases. We used the SAD three-dimensional structure to model several of these SAD-like enzymes, and although their active site topologies largely mirror that of SAD, we describe a correlation between substrate specificity and amino acid substitution patterns in their active sites. The SAD structure thus provides a framework for understanding substrate specificity in this family of enzymes and for engineering new enzyme specificities.

PubMed: 15829607
DOI: 10.1105/tpc.104.029983

実験手法

X-RAY DIFFRACTION (1.65 Å)