2YFU

CBM62 FROM CLOSTRIDIUM THERMOCELLUM XYL5A

「2Y9S」から置き換えられました

2YFU の概要

• エントリーDOI: 10.2210/pdb2yfu/pdb
• 関連するPDBエントリー: 2YFZ 2YG0
• 分子名称: CARBOHYDRATE BINDING FAMILY 6, CALCIUM ION, GLYCEROL, ... (4 entities in total)
• 機能のキーワード: sugar binding protein, carbohydrate binding family 6
• 由来する生物種: CLOSTRIDIUM THERMOCELLUM
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 17108.75

構造登録者

Montanier, C.Y.,Correia, M.A.S.,Flint, J.E.,Zhu, Y.,Basle, A.,Mckee, L.S.,Prates, J.A.M.,Polizzi, S.J.,Coutinho, P.M.,Henrissat, B.,Fontes, C.M.G.A.,Gilbert, H.J. (登録日: 2011-04-08, 公開日: 2011-05-18, 最終更新日: 2024-05-08)

主引用文献

Montanier, C.Y.,Correia, M.A.S.,Flint, J.E.,Zhu, Y.,Basle, A.,Mckee, L.S.,Prates, J.A.M.,Polizzi, S.J.,Coutinho, P.M.,Lewis, R.J.,Henrissat, B.,Fontes, C.M.G.A.,Gilbert, H.J.
A Novel, Noncatalytic Carbohydrate-Binding Module Displays Specificity for Galactose-Containing Polysaccharides Through Calcium-Mediated Oligomerization.
J.Biol.Chem., 286:22499-, 2011

PubMed Abstract: The enzymic degradation of plant cell walls plays a central role in the carbon cycle and is of increasing environmental and industrial significance. The catalytic modules of enzymes that catalyze this process are generally appended to noncatalytic carbohydrate-binding modules (CBMs). CBMs potentiate the rate of catalysis by bringing their cognate enzymes into intimate contact with the target substrate. A powerful plant cell wall-degrading system is the Clostridium thermocellum multienzyme complex, termed the "cellulosome." Here, we identify a novel CBM (CtCBM62) within the large C. thermocellum cellulosomal protein Cthe_2193 (defined as CtXyl5A), which establishes a new CBM family. Phylogenetic analysis of CBM62 members indicates that a circular permutation occurred within the family. CtCBM62 binds to d-galactose and l-arabinopyranose in either anomeric configuration. The crystal structures of CtCBM62, in complex with oligosaccharides containing α- and β-galactose residues, show that the ligand-binding site in the β-sandwich protein is located in the loops that connect the two β-sheets. Specificity is conferred through numerous interactions with the axial O4 of the target sugars, a feature that distinguishes galactose and arabinose from the other major sugars located in plant cell walls. CtCBM62 displays tighter affinity for multivalent ligands compared with molecules containing single galactose residues, which is associated with precipitation of these complex carbohydrates. These avidity effects, which confer the targeting of polysaccharides, are mediated by calcium-dependent oligomerization of the CBM.

PubMed: 21454512
DOI: 10.1074/JBC.M110.217372

実験手法

X-RAY DIFFRACTION (1.65 Å)