4IPL

The crystal structure of 6-phospho-beta-glucosidase BglA-2 from Streptococcus pneumoniae

4IPL の概要

• エントリーDOI: 10.2210/pdb4ipl/pdb
• 関連するPDBエントリー: 4IPN
• 分子名称: 6-phospho-beta-glucosidase, GLYCEROL (3 entities in total)
• 機能のキーワード: hydrolase
• 由来する生物種: Streptococcus pneumoniae
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 112544.02

構造登録者

Yu, W.L.,Jiang, Y.L.,Andreas, P.,Cheng, W.,Bai, X.H.,Ren, Y.M.,Thompsonn, J.,Zhou, C.Z.,Chen, Y.X. (登録日: 2013-01-10, 公開日: 2013-04-24, 最終更新日: 2024-02-28)

主引用文献

Yu, W.L.,Jiang, Y.L.,Pikis, A.,Cheng, W.,Bai, X.H.,Ren, Y.M.,Thompson, J.,Zhou, C.Z.,Chen, Y.
Structural insights into the substrate specificity of a 6-phospho-&[beta]-glucosidase BglA-2 from Streptococcus pneumoniae TIGR4
J.Biol.Chem., 288:14949-14958, 2013

PubMed Abstract: The 6-phospho-β-glucosidase BglA-2 (EC 3.2.1.86) from glycoside hydrolase family 1 (GH-1) catalyzes the hydrolysis of β-1,4-linked cellobiose 6-phosphate (cellobiose-6'P) to yield glucose and glucose 6-phosphate. Both reaction products are further metabolized by the energy-generating glycolytic pathway. Here, we present the first crystal structures of the apo and complex forms of BglA-2 with thiocellobiose-6'P (a non-metabolizable analog of cellobiose-6'P) at 2.0 and 2.4 Å resolution, respectively. Similar to other GH-1 enzymes, the overall structure of BglA-2 from Streptococcus pneumoniae adopts a typical (β/α)8 TIM-barrel, with the active site located at the center of the convex surface of the β-barrel. Structural analyses, in combination with enzymatic data obtained from site-directed mutant proteins, suggest that three aromatic residues, Tyr(126), Tyr(303), and Trp(338), at subsite +1 of BglA-2 determine substrate specificity with respect to 1,4-linked 6-phospho-β-glucosides. Moreover, three additional residues, Ser(424), Lys(430), and Tyr(432) of BglA-2, were found to play important roles in the hydrolytic selectivity toward phosphorylated rather than non-phosphorylated compounds. Comparative structural analysis suggests that a tryptophan versus a methionine/alanine residue at subsite -1 may contribute to the catalytic and substrate selectivity with respect to structurally similar 6-phospho-β-galactosidases and 6-phospho-β-glucosidases assigned to the GH-1 family.

PubMed: 23580646
DOI: 10.1074/jbc.M113.454751

実験手法

X-RAY DIFFRACTION (2.004 Å)