Merck, SRP0219-50UG, CD45 Active human

General description
Protein tyrosine phosphatase, receptor type C (PTPRC) or leucocyte common antigen CD45 is expressed on T-cells and is found in multiple isoforms. The extracellular domain of the protein is predicted to have an amino-terminal mucin-like segment, a cysteine-rich domain and three fibronectin type 3 domains. The gene encoding this protein is localized on human chromosome 1q31.3.
Protein tyrosine phosphatase. Catalytic domain, (584-1256) (Gene bank accession number NM_080922) with N-terminal His tag, MW = 75 kDa, expressed in a Baculovirus Sf9 expression system.
Application
Useful for the study of enzyme kinetics, regulation, and to dephosphorylate target substrates.
Biochem/physiol Actions
Protein tyrosine phosphatase, receptor type C (PTPRC) or leucocyte common antigen CD45 acts as a protein tyrosine phosphatase in leucocyte signaling. It has a role in flow cytometric diagnostics in leukemia. By dephosphorylation of Src kinases, the protein acts as a regulator of antigen receptor signaling in T and B cells. As a negative regulator of Janus kinases, CD45 inhibits cytokine receptor signaling.
Physical form
Formulation: recombinant proteins were eluted in 25 mM Tris-HCL, 75 mM NaCl, pH 8.0, 0.05% Tween, 5 mM DTT and 50% glycerol.
Preparation Note
Thaw on ice. Upon first thaw, briefly spin tube containing enzyme to recover full content of the tube. Aliquot enzyme into single use aliquots. Store remaining undiluted enzyme in aliquots at -70°C. Note: Enzyme is very sensitive to freeze/thaw cycles.
Other Notes
One unit will hydrolyze 1 nmol p-nitrophenyl phosphate per minute at pH 7.4 and 30°C.