title: The structure of sucrose synthase-1 from Arabidopsis thaliana and its functional implications.
abstract: Sucrose transport is the central system for the allocation of carbon resources in vascular plants. During growth and development, plants control carbon distribution by coordinating sites of sucrose synthesis and cleavage in different plant organs and different cellular locations. Sucrose synthase, which reversibly catalyzes sucrose synthesis and cleavage, provides a direct and reversible means to regulate sucrose flux. Depending on the metabolic environment, sucrose synthase alters its cellular location to participate in cellulose, callose, and starch biosynthesis through its interactions with membranes, organelles, and cytoskeletal actin. The x-ray crystal structure of sucrose synthase isoform 1 from Arabidopsis thaliana (AtSus1) has been determined as a complex with UDP-glucose and as a complex with UDP and fructose, at 2.8- and 2.85-Å resolutions, respectively. The AtSus1 structure provides insights into sucrose catalysis and cleavage, as well as the regulation of sucrose synthase and its interactions with cellular targets.
authors.affiliation: Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zheng
authors.affiliation: Life Sciences Collaborative Access Team, Northwestern University, Argonne, Illinois 60439.
authors.forename: Spencer
authors.initials: S
authors.lastname: Anderson
authors.affiliation: Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824.
authors.forename: Yanfeng
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824. Electronic address: garavito@msu.edu.
authors.forename: R Michael
authors.initials: RM
authors.lastname: Garavito
mesh_terms: D017360:Arabidopsis / Q000201:enzymology*; D029681:Arabidopsis Proteins / Q000737:chemistry*; D002384:Catalysis; D018360:Crystallography, X-Ray; D005964:Glucosyltransferases / Q000737:chemistry*; D017434:Protein Structure, Tertiary; D013329:Structure-Activity Relationship; D014532:Uridine Diphosphate Glucose / Q000737:chemistry*
chemical_list: D029681:Arabidopsis Proteins; D005964:Glucosyltransferases; C022699:sucrose synthase; D014532:Uridine Diphosphate Glucose