title: Structure of the starch-debranching enzyme barley limit dextrinase reveals homology of the N-terminal domain to CBM21.
abstract: Barley limit dextrinase (HvLD) is a debranching enzyme from glycoside hydrolase family 13 subfamily 13 (GH13_13) that hydrolyses α-1,6-glucosidic linkages in limit dextrins derived from amylopectin. The structure of HvLD was solved and refined to 1.9 Å resolution. The structure has a glycerol molecule in the active site and is virtually identical to the structures of HvLD in complex with the competitive inhibitors α-cyclodextrin and β-cyclodextrin solved to 2.5 and 2.1 Å resolution, respectively. However, three loops in the N-terminal domain that are shown here to resemble carbohydrate-binding module family 21 were traceable and were included in the present HvLD structure but were too flexible to be traced and included in the structures of the two HvLD-inhibitor complexes.
authors.affiliation: Enzyme and Protein Chemistry, Department of Systems Biology, Technical University of Denmark, Søltofts Plads, Building 224, 2800 Kgs. Lyngby, Denmark.
authors.forename: Marie Sofie
authors.initials: MS
authors.lastname: Møller
authors.forename: Maher
authors.initials: M
authors.lastname: Abou Hachem
authors.forename: Birte
authors.initials: B
authors.lastname: Svensson
authors.forename: Anette
authors.initials: A
authors.lastname: Henriksen
mesh_terms: D006026:Glycoside Hydrolases / Q000737:chemistry* / Q000378:metabolism; D001467:Hordeum / Q000201:enzymology*; D008958:Models, Molecular; D017434:Protein Structure, Tertiary; D013213:Starch / Q000737:chemistry / Q000378:metabolism; D040681:Structural Homology, Protein; D013379:Substrate Specificity
chemical_list: D013213:Starch; D006026:Glycoside Hydrolases; C100181:pullulanase