2Z72

New Structure Of Cold-Active Protein Tyrosine Phosphatase At 1.1 Angstrom

2Z72 の概要

• エントリーDOI: 10.2210/pdb2z72/pdb
• 分子名称: Protein-tyrosine-phosphatase, ZINC ION (3 entities in total)
• 機能のキーワード: cold-active enzyme, psychrophile, protein tyrosine phosphatase, shewanella sp., hydrolase
• 由来する生物種: Shewanella sp.
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 38979.74

構造登録者

Tsuruta, H.,Mikami, B.,Yamamoto, C.,Yamagata, H. (登録日: 2007-08-10, 公開日: 2008-07-29, 最終更新日: 2024-10-23)

主引用文献

Tsuruta, H.,Mikami, B.,Yamamoto, C.,Yamagata, H.
The role of group bulkiness in the catalytic activity of psychrophile cold-active protein tyrosine phosphatase
Febs J., 275:4317-4328, 2008

PubMed Abstract: The cold-active protein tyrosine phosphatase found in psychrophilic Shewanella species exhibits high catalytic efficiency at low temperatures as well as low thermostability, both of which are characteristics shared by many cold-active enzymes. The structure of cold-active protein tyrosine phosphatase is notable for the presence of three hydrophobic sites (termed the CA, Zn-1 and Zn-2 sites) behind the loop structures comprising the catalytic region. To identify the structural components responsible for specific enzyme characteristics, we determined the structure of wild-type cold-active protein tyrosine phosphatase at high resolution (1.1 A) and measured the catalytic efficiencies of enzymes containing mutations in the three hydrophobic sites. The bulkiness of the amino acid side chains in the core region of the Zn-1 site strongly affects the thermostability and the catalytic efficiency at low temperatures. The mutant enzyme I115M possessed a higher kcat at low temperatures. Elucidation of the crystal structure of I115M at a resolution of 1.5 A revealed that the loop structures involved in retaining the nucleophilic group and the acid catalyst are more flexible than in the wild-type enzyme.

PubMed: 18647345
DOI: 10.1111/j.1742-4658.2008.06575.x

実験手法

X-RAY DIFFRACTION (1.1 Å)