Spatial conformation and topography of the tyrosine aromatic ring in substrate recognition by protein tyrosine kinases.
The side chain orientation of the tyrosine residue included in a peptide, which is an excellent substrate of Syk tyrosine kinase, was fixed in different conformations by either incorporating the tyrosine in cyclic structures (6-OH-Tic, 5-OH-Aic, and Hat derivatives) or adding a sterically bulky substituent in the tyrosine side chain moiety (beta-MeTyr). Synthetic peptides containing tyrosine analogues displaying different side chain orientations were analyzed by NMR techniques and tested as potential substrates of the nonreceptor tyrosine kinases Syk, Csk, Lyn, and Fyn. The "rotamer scan" of the phosphorylatable residue generated optimal substrates in terms of both phosphorylation efficiency and selectivity for Syk tyrosine kinase, while the peptidomimetics were not recognized by the other tyrosine kinases. In particular, l-beta-MeTyr and d-Hat containing peptides resulted to be both suitable substrates for the specific monitoring of Syk and consensus sequence scaffolds for the design of potential inhibitors highly selective for this tyrosine kinase.
Ruzza
Paolo
P
Institute of Biomolecular Chemistry of CNR, Padova Unit, via F. Marzolo 1, 35131 Padova, Italy. paolo.ruzza@unipd.it
Cesaro
Luca
L
Tourwé
Dirk
D
Calderan
Andrea
A
Biondi
Barbara
B
Maes
Veronique
V
Menegazzo
Ileana
I
Osler
Alessio
A
Rubini
Chiara
C
Guiotto
Andrea
A
Pinna
Lorenzo A
LA
Borin
Gianfranco
G
Donella-Deana
Arianna
A
D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D008968:Molecular Conformation; D018716:Molecular Mimicry; D009842:Oligopeptides / Q000138:chemical synthesis / Q000737:chemistry*; D010766:Phosphorylation; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000737:chemistry*; D013237:Stereoisomerism; D013329:Structure-Activity Relationship; D013379:Substrate Specificity; D014443:Tyrosine / Q000737:chemistry*
D009842:Oligopeptides; D014443:Tyrosine; D011505:Protein-Tyrosine Kinases