Limited enzymatic cleavage of pig immunoglobulin G and of specific antibodies. IV. Characteristics of the tFc' fragment obtained from the S-sulpho derivative of non-specific immunoglobulin G.
By tryptic cleavage of the S-sulpho derivative of non-specific pig IgG and subsequent separation by gel chromatography on Sephadex G-100 a fragment with molecular mass 11 900 +/- 500 was obtained. This fragment originates in the Fc part of the molecule because it precipitates with anti-Fc serum. It was therefore designated tFc'. From the pFc' fragment obtained by peptic cleavage it significantly differs in amino acid composition. tFc' fragment was subjected to ion-exchange chromatography on SE-Sephadex at pH 3.0 in a dissociating medium containing 8 M urea. Three major variants of tFc' fragment were purified by rechromatography and characterized by amino acid composition and by peptide maps. Their characteristic features are a high half-cystine content and a low content of arginine, histidine and methionine. The characteristics of all the three variants of tFc' fragment suggest that they most probably originate in the CH2 domain of immunoglobulin G.
D000595:Amino Acid Sequence; D000818:Animals; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D007141:Immunoglobulin Fc Fragments / Q000032:analysis*; D007128:Immunoglobulin Fragments / Q000032:analysis*; D007074:Immunoglobulin G / Q000032:analysis*; D066298:In Vitro Techniques; D010455:Peptides / Q000032:analysis; D013552:Swine; D014357:Trypsin
D007141:Immunoglobulin Fc Fragments; D007128:Immunoglobulin Fragments; D007074:Immunoglobulin G; D010455:Peptides; D014357:Trypsin