4bfn

Crystal Structure of the Starch-Binding Domain from Rhizopus oryzae Glucoamylase in Complex with isomaltotetraose

spinqualitylabelsall models 4bfn, resolution 1.32Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 4bfn is a 1 chain structure with sequence from Atcc 56536. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: GLC Related: 4bfo Activity: Glucan 1,4-alpha-glucosidase, with EC number 3.2.1.3 Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Publication Abstract from PubMed Glucoamylases are responsible for hydrolysis of starch and polysaccharides to yield beta-D-glucose. Rhizopus oryzae glucoamylase (RoGA) is composed of an N-terminal starch binding domain (SBD) and a C-terminal catalytic domain connected by an O-glycosylated linker. Two carbohydrate-binding sites in RoSBD have been identified, site I is created by three highly conserved aromatic residues, Trp47, Tyr83, and Tyr94, and site II is built up by Tyr32 and Phe58. Here the two crystal structures of RoSBD in complex with only alpha-(1,6)-linked isomaltotriose (RoSBD-isoG3) and isomaltotetraose (RoSBD-isoG4) have been determined at 1.2 A and 1.3 A, respectively. Interestingly, site II binding is observed in both complexes, while site I binding is only found in the RoSBD-isoG4 complex. Hence, site II acts as the recognition binding site for carbohydrate and site I accommodates site II to bind isoG4. Site I participates in sugar binding only when the number of glucosyl units of oligosaccharides is more than three. Taken together, two carbohydrate binding sites in RoSBD cooperate to reinforce binding mode of glucoamylase with polysaccharides as well as the starch. (c) Proteins 2013;. (c) 2013 Wiley Periodicals, Inc. Crystal Structures of Starch Binding Domain from Rhizopus oryzae Glucoamylase in Complex with Isomaltooligosaccharide: Insights into Polysaccharide Binding Mechanism of CBM21 Family.,Chu CH, Li KM, Lin SW, Chang MD, Jiang TY, Sun YJ Proteins. 2013 Oct 9. doi: 10.1002/prot.24446. PMID:24108499 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

Proteopedia Page Contributors and Editors (what is this?)

OCA