title: p-Benzoyl-L-phenylalanine, a new photoreactive amino acid. Photolabeling of calmodulin with a synthetic calmodulin-binding peptide.
abstract: A new photoreactive amino acid analog, p-benzoyl-L-phenylalanine, is described. Convenient methods for the preparation of this amino acid and its subsequent incorporation into synthetic peptides by the solid-phase technique are outlined. To illustrate its utility, p-benzoyl-L-phenylalanine was substituted in place of tryptophan in a 17-residue calmodulin-binding peptide. The substitution did not measurably affect the affinity of this peptide for calmodulin. When this peptide was photolyzed at 350 nm in a 1:1 molar ratio with calmodulin in the presence of 500 microM CaCl2, 70% of the calmodulin was derivatized. The specificity of the reaction was investigated by photolysis in the absence of CaCl2 where little binding occurs; under these conditions little or no photolabeling occurred.
mesh_terms: D000345:Affinity Labels / Q000494:pharmacology*; D000818:Animals; D002147:Calmodulin / Q000378:metabolism*; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D007202:Indicators and Reagents; D007700:Kinetics; D008297:Male; D010446:Peptide Fragments / Q000032:analysis; D010649:Phenylalanine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000494:pharmacology; D010782:Photolysis; D013329:Structure-Activity Relationship; D013737:Testis / Q000378:metabolism
chemical_list: D000345:Affinity Labels; D002147:Calmodulin; D007202:Indicators and Reagents; D010446:Peptide Fragments; D010649:Phenylalanine; C042925:N-(2-benzoylphenyl)alanine