Model flavoproteins : Interaction of ribofIavin-5'-monophosphate with poly-( α –L-lysine) and poly-( α -L-histidine).

The interactions of flavin mononucleotide (riboflavin-5'-monophosphate) with two polypeptides, poly-(α-L-lysine) and poly-(α-L-histidine) in water and 0.05 Μ phosphate buffer were studied by measuring circular dichroism in the pH range 3 to 11. The interation of flavin mononucleotide with the two polypeptides was due to hydrophobic as well as ionic associations and was further influenced by the involvement of the ribityl side chain. The results of the present study have shown that small changes in the environmental conditions of the interacting molecules could modify their mode of interaction considerably.