2-Chloromercuri-4-nitrophenol-modified sites of creatine kinase confirmed by FPLC
MNP-modified tryptic peptides of creatine kinase have been separated with two-dimensional electrophoresis, but the location of the SH groups of creatine kinase modified by MNP still seemed to be vague until recently(Laue, M.C.& Quiocho, F. A., 1977). Two peptides have now been found to be the MNP-modified peptides with reversed-phase FPLC methods, and the amino acid compositions of these two peptides are in agreement with those of the two peptides around Cys-253, respectively. These findings indicate that the two buried SH groups of creatine kinase have been modified by MNP.