3GXK

The crystal structure of g-type lysozyme from Atlantic cod (Gadus morhua L.) in complex with NAG oligomers sheds new light on substrate binding and the catalytic mechanism. Native structure to 1.9

3GXK の概要

• エントリーDOI: 10.2210/pdb3gxk/pdb
• 関連するPDBエントリー: 3GXR
• 分子名称: Goose-type lysozyme 1, COBALT (II) ION (3 entities in total)
• 機能のキーワード: atlantic cod, fish lysozyme, active site residues, substrate binding sites, surface potential, muramidase activity, immune system, hydrolase
• 由来する生物種: Gadus morhua (Atlantic cod)
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 83441.90

構造登録者

Helland, R.,Larsen, R.L.,Finstad, S.,Kyomuhendo, P.,Larsen, A.N. (登録日: 2009-04-02, 公開日: 2009-10-20, 最終更新日: 2023-11-01)

主引用文献

Helland, R.,Larsen, R.L.,Finstad, S.,Kyomuhendo, P.,Larsen, A.N.
Crystal structures of g-type lysozyme from Atlantic cod shed new light on substrate binding and the catalytic mechanism.
Cell.Mol.Life Sci., 66:2585-2598, 2009

PubMed Abstract: Crystal structures of Atlantic cod lysozyme have been solved with and without ligand bound in the active site to 1.7 and 1.9 A resolution, respectively. The structures reveal the presence of NAG in the substrate binding sites at both sides of the catalytic Glu73, hence allowing the first crystallographic description of the goose-type (g-type) lysozyme E-G binding sites. In addition, two aspartic acid residues suggested to participate in catalysis (Asp101 and Asp90) were mutated to alanine. Muramidase activity data for two single mutants and one double mutant demonstrates that both residues are involved in catalysis, but Asp101 is the more critical of the two. The structures and activity data suggest that a water molecule is the nucleophile completing the catalytic reaction, and the roles of the aspartic acids are to ensure proper positioning of the catalytic water.

PubMed: 19543850
DOI: 10.1007/s00018-009-0063-x

実験手法

X-RAY DIFFRACTION (1.9 Å)