title: Affinity labelling of proteinases with tryptic specificity by peptides with C-terminal lysine chloromethyl ketone.
abstract: Methods are described for the synthesis of peptides terminating in Lys-CH(2)Cl. The products were examined as affinity labels for several enzymes of trypsin-like specificity which are resistant to Tos-Lys-CH(2)Cl. In part, the inertness of the latter may be due to the sulphonamide group, since Z-Lys-CH(2)Cl was more effective. However, a number of tripeptides with C-terminal Lys-CH(2)Cl were superior in their ability to inactivate subtilisin, thrombin and plasma kallikrein. The possibility of developing enzyme-specific reagents selective for members within the trypsin-like group is demonstrated by Ala-Phe-Lys-CH(2)Cl, which readily inactivates plasma kallikrein but not thrombin.
mesh_terms: D000590:Amino Acid Chloromethyl Ketones; D001665:Binding Sites; D002713:Chlorine; D003959:Diamines; D004950:Esterases; D006801:Humans; D007202:Indicators and Reagents; D007610:Kallikreins; D007659:Ketones; D008239:Lysine / Q000031:analogs & derivatives*; D010447:Peptide Hydrolases; D010455:Peptides / Q000138:chemical synthesis; D011480:Protease Inhibitors; D013381:Subtilisins / Q000037:antagonists & inhibitors; D013917:Thrombin; D014357:Trypsin
chemical_list: D000590:Amino Acid Chloromethyl Ketones; D003959:Diamines; D007202:Indicators and Reagents; D007659:Ketones; D010455:Peptides; D011480:Protease Inhibitors; C010396:lysine chloromethyl ketone; D002713:Chlorine; D004950:Esterases; D010447:Peptide Hydrolases; D007610:Kallikreins; D013381:Subtilisins; D014357:Trypsin; D013917:Thrombin; D008239:Lysine