OH radical-induced products of tyrosine peptides.
Reactions of radiation-generated OH radicals with tyrosine and its homopeptides, i.e. L-Tyr-L-Tyr and L-Tyr-L-Tyr-L-Tyr, in N2O saturated solutions were shown to give crosslinks between the peptide chains with high yields. High-performance liquid chromatography, capillary gas chromatography and mass spectrometry were used for isolation and identification of the monomeric and dimeric products. Evidence is presented for the crosslinking to occur through C-C and C-O-C bonds. To the best of our knowledge, the formation of the ether type of crosslink is demonstrated for the first time. Mechanisms of product formation are also discussed, which involve radicals that were described in previous pulse radiolysis studies.
D002849:Chromatography, Gas; D002851:Chromatography, High Pressure Liquid; D006878:Hydroxides; D013058:Mass Spectrometry; D010455:Peptides / Q000528:radiation effects; D011854:Radiochemistry; D012996:Solutions; D014443:Tyrosine / Q000528:radiation effects; D014867:Water / Q000528:radiation effects
D006878:Hydroxides; D010455:Peptides; D012996:Solutions; D014867:Water; D014443:Tyrosine; C031356:hydroxide ion