STRUCTURAL-ANALYSIS AND QUANTITATIVE-EVALUATION OF THE MODIFICATIONS PRODUCED IN HUMAN HEMOGLOBIN BY METHYL-BROMIDE USING MASS-SPECTROMETRYAND EDMAN DEGRADATION

The present study reports a procedure developed for the identification and quantitative analysis of the adducts formed by interaction of met hyl bromide with human hemoglobin, based on combined analysis by elect rospray mass spectrometry and automated Edman degradation of either in tact globin chains or tryptic peptides of globin chains. The procedure has allowed identification of the reactive sites in human hemoglobin, and has been applied to the analysis of samples modified in vitro by methyl bromide. The results obtained represent the basis for the compl ete structural characterization of the modified hemoglobin and demonst rate the usefulness of the proposed analytical approach for the evalua tion of the degree of alkylation and the identification of modified am ino acids in proteins. (C) 1998 John Wiley & Sons, Ltd.