A comparison of the circular dichroism spectra of the subclasses of human immunoglobulin G.

Abstract

We have determined the circular dichroism of sixteen human IgG myeloma proteins representative of the four subclasses. No significant variation in β structure was observed between the subclasses. However, at wavelengths greater than 230 nm, the spectra of IgG3 myeloma proteins is quite distinct, indicating a unique conformation. Myeloma proteins of the other subclasses gave similar overall spectra, but some of the features of the negative maxima in the region of 260–280 nm appeared to be subclass-specific.