title: Isolation and partial characterization of a type IV bacterial immunoglobulin binding protein.
abstract: A series of bovine G streptococcal isolates were screened for expression of type IV Fc binding proteins. An isolate expressing high levels of type IV binding proteins was selected and expanded by use of a colony selection technique. A variety of different extraction procedures were compared and the optimal solubilization procedure was found to be hot acid extraction of the bacteria. The extracted protein could be affinity purified on a column of immobilized rabbit IgG. The type IV Fc binding protein was found to be antigenically unrelated to the type I, II or III bacterial Fc binding proteins and displayed the lowest affinity and most limited range of species and subclass reactivity of any bacterial Fc binding protein thus far characterized.
authors.affiliation: Department of Microbiology, Medical College of Ohio, Toledo 43699-0008.
authors.forename: R
authors.initials: R
authors.lastname: Raeder
authors.forename: R A
authors.initials: RA
authors.lastname: Otten
authors.forename: M D
authors.initials: MD
authors.lastname: Boyle
mesh_terms: D001426:Bacterial Proteins / Q000276:immunology* / Q000302:isolation & purification; D001483:Base Sequence; D001667:Binding, Competitive; D015153:Blotting, Western; D006801:Humans; D015151:Immunoblotting; D007141:Immunoglobulin Fc Fragments / Q000378:metabolism; D007074:Immunoglobulin G / Q000378:metabolism; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009693:Nucleic Acid Hybridization; D015345:Oligonucleotide Probes / Q000235:genetics; D013205:Staphylococcal Protein A / Q000378:metabolism; D013291:Streptococcus / Q000276:immunology*
chemical_list: D001426:Bacterial Proteins; C029152:G-substrate; C034284:IgG Fc-binding protein, Streptococcus; D007141:Immunoglobulin Fc Fragments; D007074:Immunoglobulin G; D009419:Nerve Tissue Proteins; D015345:Oligonucleotide Probes; D013205:Staphylococcal Protein A