Arginine chemical modification reagents

Arginine residues are very resistant to most of the usual reagents used for chemical modification. King (166) has reported the conversion of these residues to S-N- (2-pyrimidinyl) ornithine by treatment with malonaldehyde in 10 N HC1. Essentially complete modification of the 4 arginine residues in RNase was obtained. Peptide bond cleavage and disulfide interchange also occurred, however, and no conclusions are warranted on the relation of the properties of the product to the actual arginine modification. 

---