Home
Resources
Publications
Purification and Characterization of T Cell Protein Tyrosine Phosphatase Reveals Significant Functional Homology to Protein Tyrosine phosphatase-1B

Purification and Characterization of T Cell Protein Tyrosine Phosphatase Reveals Significant Functional Homology to Protein Tyrosine phosphatase-1B

Yolanda Romsicki, Brian P Kennedy, Ernest Asante-Appiah

Arch Biochem Biophys. 2003 Jun 1;414(1):40-50.

PMID: 12745253

Abstract:

We have developed a protocol for rapid purification of T cell protein tyrosine phosphatase (TCPTP) and the structurally related protein tyrosine phosphatase-1B (PTP-1B) from bacterial cells. The pH profile for TCPTP was bell-shaped with an optimum of 5.5. The catalytic domain and full-length versions of TCPTP bound a potent inhibitor with affinities similar to those of PTP-1B. The K(m) values for the catalytic domains of TCPTP and PTP-1B increased with increasing ionic strength, whereas the k(cat) values remained unchanged. Arrhenius plots revealed that TCPTP and PTP-1B possess similar activation energies of 25.3+/-1.2 and 18.4+/-3.0 kJ/mol, respectively. Increasing solvent microviscosity (up to 40% (w/v) sucrose) did not affect k(cat)/K(m) of either enzyme. However, high sucrose concentrations protected both enzymes from thermal inactivation. These studies show that, although they share a 72% amino acid sequence identity within their catalytic domains, TCPTP and PTP-1B are functionally very similar in vitro.

Chemicals Related in the Paper:

Catalog Number	Product Name	Structure	CAS Number	Price
IAR42417914	PTP1B full length Active human			Price

As a specialist in analytical chemical Products, Alfa Chemistry offers consumers a wealth of raw materials and a full range of technologies and services.

QUICK LINKS

HEADQUARTERS

Tel:

Fax:

Email: