The Effect of Denaturation on the Reactivity between Thiol-thiamines and Oxidized Egg Albumin.

(1, 2). However, it was reported in the foregoing paper (3), that the -S-Slinkages formed by iodine oxidation of the SH-groups of native egg albumin could react with the thiol-form of thiamine or O-benzoylthiamine (OBT) without denaturation. To investigate the effect of denaturation on the reaction is an interesting problem, giving means of elucidating the molecular structure of pro teins. Investigation was therefore made of the effects of the denaturation brought about by heating or adding urea after or prior to the iodine oxidation process on the reactivity of the -S-Sgroup formed by oxidation of SH groups in egg albumin. The reactivity was evaluated by determining the amounts of the protein-thiamine mixed disulfide produced in the reaction between thiol-type thiamines and the