2ZBM

Crystal Structure of I115M Mutant Cold-Active Protein Tyrosine Phosphatase

Summary for 2ZBM

• Entry DOI: 10.2210/pdb2zbm/pdb
• Related: 1V73
• Descriptor: Protein-tyrosine-phosphatase, ZINC ION (3 entities in total)
• Functional Keywords: hydrase, protein-tyrosine-phosphatase, metallophosphoesterase, hydrolase
• Biological source: Shewanella sp.
• Total number of polymer chains: 1
• Total formula weight: 38282.07

Authors

Tsuruta, H.,Mikami, B.,Yamamoto, C.,Yamagata, H. (deposition date: 2007-10-24, release date: 2008-07-29, Last modification date: 2024-10-30)

Primary citation

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

Experimental method

X-RAY DIFFRACTION (1.5 Å)