Limited enzymatic cleavage of pig immunoglobulin G and of specific antibodies. III. Large-scale isolation of tryptic fragments of antibodies and of non-specific immunoglobulin and characteristics of the Fc fragment.
Precipitating and non-precipitating anti-Dnp antibodies and S-sulpho non-specific IgG in gram quantities were subjected to limited cleavage by trypsin. Upon gel chromatography on Sephadex G-100 the fraction of Fab and Fc fragments was separated from incompletely split molecules and from tFc' fragments. The Fab and Fc fragments were separated from each other either by ion-exchange chromatography on QAE-Sephadex or by preparative electrophoresis in starch block. Both Fab and Fc fragments appeared to be heterogeneous as to electric charge. The Fc fragments were characterized by amino acid composition and N-terminal amino acids. The Fc fragment of non-specific IgG was cleaved by cyanogen bromide, and a C-terminal peptide containing 18 residues was isolated. Partial amino acid sequence of this peptide pointed to a high degree of homology with immunoglobulins of other animal species.
D000596:Amino Acids / Q000032:analysis; D000818:Animals; D003488:Cyanogen Bromide; D004140:Dinitrophenols / Q000276:immunology; D007140:Immunoglobulin Fab Fragments / Q000302:isolation & purification*; D007141:Immunoglobulin Fc Fragments / Q000302:isolation & purification*; D007128:Immunoglobulin Fragments / Q000302:isolation & purification*; D007074:Immunoglobulin G / Q000032:analysis*; D010455:Peptides / Q000032:analysis; D011234:Precipitins / Q000032:analysis; D013552:Swine / Q000276:immunology*
D000596:Amino Acids; D004140:Dinitrophenols; D007140:Immunoglobulin Fab Fragments; D007141:Immunoglobulin Fc Fragments; D007128:Immunoglobulin Fragments; D007074:Immunoglobulin G; D010455:Peptides; D011234:Precipitins; D003488:Cyanogen Bromide