‘Intraglobular’ Reactions and the Cyclol Structure of Proteins

Abstract

IN order to explain the effect of a protein on a certain condensation reaction, Talmud¹ has proposed a hypothesis for ‘intraglobular’ reactions, based upon Wrinch's well-known theory² of protein structure. As an example, he showed that a considerable portion of 2-5-dioxopiporazin formed by condensation of glycine ethyl ester³ in an aqueous solution of egg albumin remains in solution associated with the protein, in excess of the normal solubility limit. Talmud suggests that the reaction has taken place in large part within the hollow cyclol globules, and that the reaction product is prevented from diffusing out owing to its molecular size. By independent adsorption experiments (on heat-denatured egg albumin at 0°) Talmud believes he has shown that the amount of dioxopiperazin remaining in solution was in excess of the amounts that could be adsorbed on the surfaces of the globular protein molecules.