title: Structural Insights into Substrate Specificity of Feruloyl-CoA 6'-Hydroxylase from Arabidopsis thaliana.
abstract: Coumarins belong to an important class of plant secondary metabolites. Feruloyl-CoA 6'-hydroxylase (F6'H), a 2-oxoglutarate dependent dioxygenase (2OGD), catalyzes a pivotal step in the biosynthesis of a simple coumarin scopoletin. In this study, we determined the 3-dimensional structure of the F6'H1 apo enzyme by X-ray crystallography. It is the first reported structure of a 2OGD enzyme involved in coumarin biosynthesis and closely resembles the structure of Arabidopsis thaliana anthocyanidin synthase. To better understand the mechanism of enzyme catalysis and substrate specificity, we also generated a homology model of a related ortho-hydroxylase (C2'H) from sweet potato. By comparing these two structures, we targeted two amino acid residues and verified their roles in substrate binding and specificity by site-directed mutagenesis.
authors.affiliation: State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
authors.forename: Xinxiao
authors.initials: X
authors.lastname: Sun
authors.affiliation: Department of Biochemistry &Molecular Biology, University of Georgia, Athens, Georgia 30602, USA.
authors.forename: Dayong
authors.initials: D
authors.lastname: Zhou
authors.affiliation: Department of Biochemistry &Molecular Biology, University of Georgia, Athens, Georgia 30602, USA.
authors.forename: Palani
authors.initials: P
authors.lastname: Kandavelu
authors.affiliation: Department of Biochemistry &Molecular Biology, University of Georgia, Athens, Georgia 30602, USA.
authors.forename: Hua
authors.initials: H
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
authors.forename: Qipeng
authors.initials: Q
authors.lastname: Yuan
authors.affiliation: Department of Biochemistry &Molecular Biology, University of Georgia, Athens, Georgia 30602, USA.
authors.forename: Bi-Cheng
authors.initials: BC
authors.lastname: Wang
authors.affiliation: Department of Biochemistry &Molecular Biology, University of Georgia, Athens, Georgia 30602, USA.
authors.forename: John
authors.initials: J
authors.lastname: Rose
authors.affiliation: BioChemical Engineering Program, College of Engineering, University of Georgia, Athens, Georgia 30602, USA.
authors.forename: Yajun
authors.initials: Y
authors.lastname: Yan
mesh_terms: D017360:Arabidopsis / Q000201:enzymology*; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001665:Binding Sites; D055162:Biocatalysis; D003374:Coumarins / Q000737:chemistry / Q000378:metabolism; D018360:Crystallography, X-Ray; D049308:Dioxygenases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D056004:Molecular Dynamics Simulation; D016297:Mutagenesis, Site-Directed; D010105:Oxygenases / Q000737:chemistry / Q000378:metabolism; D017434:Protein Structure, Tertiary; D013379:Substrate Specificity
chemical_list: D029681:Arabidopsis Proteins; D003374:Coumarins; C030123:coumarin; D010105:Oxygenases; D049308:Dioxygenases; C000592514:feruloyl-CoA 6'-hydroxylase1, Arabidopsis; C118159:anthocyanidin synthase