3SXD

Crystal structure of BBBB+UDP+Gal with MPD as the cryoprotectant

3SXD の概要

• エントリーDOI: 10.2210/pdb3sxd/pdb
• 関連するPDBエントリー: 3SX3 3SX5 3SX7 3SX8 3SXA 3SXB 3SXC 3SXE 3SXG
• 分子名称: Histo-blood group ABO system transferase, URIDINE-5'-DIPHOSPHATE, beta-D-galactopyranose, ... (6 entities in total)
• 機能のキーワード: retaining glycosyltransferase, glycoprotein, blood group antigen, abo rossmann fold, metal-binding, manganese, transferase
• 由来する生物種: Homo sapiens (human)
• 細胞内の位置: Golgi apparatus, Golgi stack membrane; Single-pass type II membrane protein: P16442
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 34901.82

構造登録者

Johal, A.R.,Evans, S.V. (登録日: 2011-07-14, 公開日: 2012-02-29, 最終更新日: 2023-09-13)

主引用文献

Johal, A.R.,Schuman, B.,Alfaro, J.A.,Borisova, S.,Seto, N.O.,Evans, S.V.
Sequence-dependent effects of cryoprotectants on the active sites of the human ABO(H) blood group A and B glycosyltransferases.
Acta Crystallogr.,Sect.D, 68:268-276, 2012

PubMed Abstract: The human ABO(H) A and B blood group glycosyltransferases GTA and GTB differ by only four amino acids, yet this small dissimilarity is responsible for significant differences in biosynthesis, kinetics and structure. Like other glycosyltransferases, these two enzymes have been shown to recognize substrates through dramatic conformational changes in mobile polypeptide loops surrounding the active site. Structures of GTA, GTB and several chimeras determined by single-crystal X-ray diffraction demonstrate a range of susceptibility to the choice of cryoprotectant, in which the mobile polypeptide loops can be induced by glycerol to form the ordered closed conformation associated with substrate recognition and by MPD [hexylene glycol, (±)-2-methyl-2,4-pentanediol] to hinder binding of substrate in the active site owing to chelation of the Mn²⁺ cofactor and thereby adopt the disordered open state. Glycerol is often avoided as a cryoprotectant when determining the structures of carbohydrate-active enzymes as it may act as a competitive inhibitor for monosaccharide ligands. Here, it is shown that the use of glycerol as a cryoprotectant can additionally induce significant changes in secondary structure, a phenomenon that could apply to any class of protein.

PubMed: 22349229
DOI: 10.1107/S0907444912001801

実験手法

X-RAY DIFFRACTION (1.55 Å)