4FIX

Crystal Structure of GlfT2

4FIX の概要

• エントリーDOI: 10.2210/pdb4fix/pdb
• 関連するPDBエントリー: 4FIY
• 分子名称: UDP-galactofuranosyl transferase GlfT2, GLYCEROL, MANGANESE (II) ION, ... (5 entities in total)
• 機能のキーワード: galactofuranosyltransferase, cazy gt-2 family, glycosyltransferase, carbohydrate binding, membrane, transferase
• 由来する生物種: Mycobacterium tuberculosis
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 148097.99

構造登録者

Wheatley, R.W.,Zheng, R.B.,Lowary, T.L.,Ng, K.K.S. (登録日: 2012-06-11, 公開日: 2012-06-20, 最終更新日: 2024-02-28)

主引用文献

Wheatley, R.W.,Zheng, R.B.,Richards, M.R.,Lowary, T.L.,Ng, K.K.
Tetrameric Structure of the GlfT2 Galactofuranosyltransferase Reveals a Scaffold for the Assembly of Mycobacterial Arabinogalactan.
J.Biol.Chem., 287:28132-28143, 2012

PubMed Abstract: Biosynthesis of the mycobacterial cell wall relies on the activities of many enzymes, including several glycosyltransferases (GTs). The polymerizing galactofuranosyltransferase GlfT2 (Rv3808c) synthesizes the bulk of the galactan portion of the mycolyl-arabinogalactan complex, which is the largest component of the mycobacterial cell wall. We used x-ray crystallography to determine the 2.45-Å resolution crystal structure of GlfT2, revealing an unprecedented multidomain structure in which an N-terminal β-barrel domain and two primarily α-helical C-terminal domains flank a central GT-A domain. The kidney-shaped protomers assemble into a C(4)-symmetric homotetramer with an open central core and a surface containing exposed hydrophobic and positively charged residues likely involved with membrane binding. The structure of a 3.1-Å resolution complex of GlfT2 with UDP reveals a distinctive mode of nucleotide recognition. In addition, models for the binding of UDP-galactofuranose and acceptor substrates in combination with site-directed mutagenesis and kinetic studies suggest a mechanism that explains the unique ability of GlfT2 to generate alternating β-(1→5) and β-(1→6) glycosidic linkages using a single active site. The topology imposed by docking a tetrameric assembly onto a membrane bilayer also provides novel insights into aspects of processivity and chain length regulation in this and possibly other polymerizing GTs.

PubMed: 22707726
DOI: 10.1074/jbc.M112.347484

実験手法

X-RAY DIFFRACTION (2.45 Å)