Extraction of group C streptococcal IgG-binding receptor and characterization of the active peptides by Western blotting and isoelectric focusing.
Three different enzymatic extraction procedures were tested for their effectivity in releasing IgG-binding peptides from the streptococcal cell wall. Streptococcus equisimilis strain 12628 isolated from pig was incubated with phage-associated lysin, trypsin and Streptomyces globisporus lytic enzyme and the extracts were investigated by Western blotting, indirect erythrocyte agglutination and Ouchterlony diffusion for IgG-binding activity. With all treatments IgG-binding peptides were extracted. However, no homogenous IgG-binding material was released by the enzymes tested. In each case a multiple peptide pattern with IgG-binding activity was found. The molecular weights of the active peptides released also differed between the extraction procedures. The isoelectric points between 4.0 and 4.3 of IgG-binding components were found to be similar for all three extracts.
D000818:Animals; D001431:Bacteriological Techniques; D004591:Electrophoresis, Polyacrylamide Gel; D006386:Hemagglutination Tests; D007525:Isoelectric Focusing; D010455:Peptides / Q000302:isolation & purification*; D011961:Receptors, Fc / Q000302:isolation & purification*; D017452:Receptors, IgG; D013291:Streptococcus / Q000276:immunology*; D013552:Swine
D010455:Peptides; D011961:Receptors, Fc; D017452:Receptors, IgG