title: Application of immunoproteomics to analysis of post-translational processing of the antiphagocytic M protein of Streptococcus.
abstract: Post-translational modification of the antiphagocytic M1 protein of Streptococcus pyogenes can influence its binding properties for human immunoglobulin G subclasses and its invasive potential. Current methods of monitoring this modification event involve N-terminal sequencing and are cumbersome, slow and not amenable to routine analysis. In this study we demonstrate that surface enhanced laser desorption/ionization-time of flight mass spectrometry can be used to monitor modification of the M1 protein by the secreted bacterial cysteine protease, SpeB. This method, when combined with a specific antibody capture step provides a specific, rapid and sensitive assay for key virulence factors of the important human pathogen Streptococcus pyogenes.
authors.affiliation: Department of Microbiology and Immunology, Medical College of Ohio, Toledo, OH, USA.
authors.forename: Terence G
authors.initials: TG
authors.lastname: Romer
authors.forename: Michael D P
authors.initials: MD
authors.lastname: Boyle
mesh_terms: D000595:Amino Acid Sequence; D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry* / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D001426:Bacterial Proteins; D002352:Carrier Proteins / Q000737:chemistry* / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D003546:Cysteine Endopeptidases / Q000378:metabolism; D006801:Humans; D007120:Immunochemistry; D008969:Molecular Sequence Data; D011499:Protein Processing, Post-Translational; D040901:Proteomics / Q000379:methods*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013297:Streptococcus pyogenes / Q000235:genetics* / Q000378:metabolism* / Q000472:pathogenicity; D014774:Virulence
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D002352:Carrier Proteins; C014689:streptococcal M protein; D003546:Cysteine Endopeptidases; C042477:streptopain