1W0O

Vibrio cholerae sialidase

1W0O の概要

• エントリーDOI: 10.2210/pdb1w0o/pdb
• 関連するPDBエントリー: 1KIT 1W0P
• 分子名称: SIALIDASE, 2-DEOXY-2,3-DEHYDRO-N-ACETYL-NEURAMINIC ACID, CALCIUM ION, ... (5 entities in total)
• 機能のキーワード: vibrio cholerae, sialidase, glycosidase, hydrolase
• 由来する生物種: VIBRIO CHOLERAE
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 86435.57

構造登録者

Moustafa, I.,Connaris, H.,Taylor, M.,Zaitsev, V.,Wilson, J.C.,Kiefel, M.J.,von-Itzstein, M.,Taylor, G. (登録日: 2004-06-09, 公開日: 2004-07-08, 最終更新日: 2024-05-08)

主引用文献

Moustafa, I.,Connaris, H.,Taylor, M.,Zaitsev, V.,Wilsonm, J.C.,Kiefel, J.,Von-Itzstein, M.,Taylor, G.
Sialic Acid Recognition by Vibrio Cholerae Neuraminidase
J.Biol.Chem., 279:40819-, 2004

PubMed Abstract: Vibrio cholerae neuraminidase (VCNA) plays a significant role in the pathogenesis of cholera by removing sialic acid from higher order gangliosides to unmask GM1, the receptor for cholera toxin. We previously showed that the structure of VCNA is composed of a central beta-propeller catalytic domain flanked by two lectin-like domains; however the nature of the carbohydrates recognized by these lectin domains has remained unknown. We present here structures of the enzyme in complex with two substrates, alpha-2,3-sialyllactose and alpha-2,6-sialyllactose. Both substrate complexes reveal the alpha-anomer of N-acetylneuraminic acid (Neu5Ac) bound to the N-terminal lectin domain, thereby revealing the role of this domain. The large number of interactions suggest a relatively high binding affinity for sialic acid, which was confirmed by calorimetry, which gave a Kd approximately 30 microm. Saturation transfer difference NMR using a non-hydrolyzable substrate, Neu5,9Ac2-2-S-(alpha-2,6)-GlcNAcbeta1Me, was also used to map the ligand interactions at the VCNA lectin binding site. It is well known that VCNA can hydrolyze both alpha-2,3- and alpha-2,6-linked sialic acid substrates. In this study using alpha-2,3-sialyllactose co-crystallized with VCNA it was revealed that the inhibitor 2-deoxy-2,3-didehydro-N-acetylneuraminic acid (Neu5Ac2en) was bound at the catalytic site. This observation supports the notion that VCNA can produce its own inhibitor and has been further confirmed by 1H NMR analysis. The discovery of the sialic acid binding site in the N-lectin-like domain suggests that this might help target VCNA to sialic acid-rich environments, thereby enhancing the catalytic efficiency of the enzyme.

PubMed: 15226294
DOI: 10.1074/JBC.M404965200

実験手法

X-RAY DIFFRACTION (1.9 Å)