Linker length dependent binding of a focal adhesion kinase derived peptide to the Src SH3–SH2 domains

The interaction between a peptide encompassing the SH3 and SH2 binding motifs of focal adhesion kinase (FAK) and the Src SH3–SH2 domains has been investigated with NMR spectroscopy and calorimetry. The binding to both motifs is anti-cooperative. Reduction of the long linker connecting the motifs does not lead to cooperativity. Short linkers that do not allow simultaneous intramolecular binding of the peptide to both motifs cause peptide-mediated dimerisation, even with a linker of only three amino acids. The role of the SH3 binding motif is discussed in view of the independent nature of the SH interactions.Structured summaryFAK_p3 and Srcbind by nuclear magnetic resonance (View interaction)FAK_p2 and Srcbind by nuclear magnetic resonance (View interaction)FAK_p32 and Srcbind by nuclear magnetic resonance (View interaction)FAK_p2 and Srcbind by isothermal titration calorimetry (View interaction)