Identification and characterization of a novel synthetic peptide substrate specific for Src-family protein tyrosine kinases.
Using a random combinatorial peptide library method [Wu, J., Ma, Q. N. & Lam, K. S. (1994) Biochemistry 33, 14825-14833] a novel peptide, YIYGSFK, was identified as a substrate for p60c-src protein tyrosine kinase. Mass spectrometric analysis showed that tyrosine-3 from the N-terminus was the phosphorylation site. Kinetic studies showed that the Km of YIYGSFK for p60c-src was 55 microM, about 6.4-fold lower than a peptide derived from p34cdc2 [cdc2(6-20), KVEKIGEGTYGVVYK], which had been reported to be a specific and efficient substrate for the Src-family protein tyrosine kinases. Comparison of the specificity of YIYGSFK and cdc2(6-20) as a substrate for various Src-family and non-Src-family protein tyrosine kinases suggests that YIYGSFK is a much more specific and efficient substrate for the Src-family protein tyrosine kinases.
Lam
K S
KS
Arizona Cancer Center, University of Arizona, Tucson, USA.
Wu
J
J
Lou
Q
Q
D000595:Amino Acid Sequence; D016203:CDC2 Protein Kinase / Q000737:chemistry; D016391:Genes, src; D007700:Kinetics; D008969:Molecular Sequence Data; D005810:Multigene Family; D010455:Peptides / Q000737:chemistry*; D016392:Proto-Oncogene Proteins pp60(c-src) / Q000235:genetics*; D013379:Substrate Specificity
D010455:Peptides; D016392:Proto-Oncogene Proteins pp60(c-src); D016203:CDC2 Protein Kinase