Theoretical models for the covalent assembly of immunoglobulins

Theoretical models for the formation of interchain disulfide bonds in noncovalently assembled immunoglobulin molecules are presented. The formalism handles independent and cooperative bond formation with equal ease. Analysis of certain experimental results on the covalent assembly of human immunoglobulin G yields information about the pathway of assembly. A model in which the formation of bonds between the light and heavy chains is independent of, but twice as fast as, those between two heavy chains, gives satisfactory agreement with these results. Simple models involving cooperative bond formation are also considered, but the experiments being analyzed are not accurate enough to unambiguously implicate any cooperative pathway.