[Nepsilon-(beta-Aspartyl)lysine and Nepsilon-(gamma-glutamyl)lysine crosslinkings in bovine colostrum (author's transl)].

In bovine colostrum which was defatted and totally hydrolyzed by proteolytic enzymes, the isopeptides Asp Lys and Glu Lys were identified by ion-exchange chromatography and preparative separation. Isopeptides were identified in two of seven samples of colostrum. It is still to be clarified whether there is a correlation between the amound of gamma-glutamyltransferase and the appearance of these crosslinkings.