1GB9

CRYSTAL STRUCTURE OF MUTANT HUMAN LYSOZYME SUBSTITUTED AT THE SURFACE POSITIONS

1GB9 の概要

• エントリーDOI: 10.2210/pdb1gb9/pdb
• 関連するPDBエントリー: 1GAY 1GAZ 1GB0 1GB2 1GB3 1GB5 1GB6 1GB7 1GB8 1GBO 1GBW 1GBX 1GBY 1GBZ 2MEI
• 分子名称: LYSOZYME, SODIUM ION (3 entities in total)
• 機能のキーワード: surface mutant, hydrolase
• 由来する生物種: Homo sapiens (human)
• 細胞内の位置: Secreted: P61626
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 14791.73

構造登録者

Funahashi, J.,Takano, K.,Yamagata, Y.,Yutani, K. (登録日: 2000-06-26, 公開日: 2000-07-27, 最終更新日: 2024-10-30)

主引用文献

Funahashi, J.,Takano, K.,Yamagata, Y.,Yutani, K.
Role of surface hydrophobic residues in the conformational stability of human lysozyme at three different positions.
Biochemistry, 39:14448-14456, 2000

PubMed Abstract: To evaluate the contribution of the amino acid residues on the surface of a protein to its stability, a series of hydrophobic mutant human lysozymes (Val to Gly, Ala, Leu, Ile, Met, and Phe) modified at three different positions on the surface, which are located in the alpha-helix (Val 110), the beta-sheet (Val 2), and the loop (Val 74), were constructed. Their thermodynamic parameters of denaturation and crystal structures were examined by calorimetry and by X-ray crystallography at 100 K, respectively. Differences in the denaturation Gibbs energy change between the wild-type and the hydrophobic mutant proteins ranged from 4.6 to -9.6 kJ/mol, 2.7 to -1.5 kJ/mol, and 3.6 to -0.2 kJ/mol at positions 2, 74, and 110, respectively. The identical substitution at different positions and different substitutions at the same position resulted in different degrees of stabilization. Changes in the stability of the mutant proteins could be evaluated by a unique equation considering the conformational changes due to the substitutions [Funahashi et al. (1999) Protein Eng. 12, 841-850]. For this calculation, secondary structural propensities were newly considered. However, some mutant proteins were not adapted to the equation. The hydration structures around the mutation sites of the exceptional mutant proteins were affected due to the substitutions. The stability changes in the exceptional mutant proteins could be explained by the formation or destruction of the hydration structures. These results suggest that the hydration structure mediated via hydrogen bonds covering the protein surface plays an important role in the conformational stability of the protein.

PubMed: 11087397
DOI: 10.1021/bi0015717

実験手法

X-RAY DIFFRACTION (1.8 Å)