title: Monoclonal antibodies against Streptococcus pneumoniae detect epitopes on eubacterial ribosomal proteins L7/L12 and on streptococcal elongation factor Ts.
abstract: Two monoclonal antibodies (mAbs) designated 144,H-3 (IgG2a) and 218,C-5 (IgM) were produced after immunization of mice with two different heat-treated and sonicated pneumococcal strains. Western blotting, with solubilized proteins from different bacterial genera and from mammalian lymphocytes, showed that both mAbs reacted with a protein of approximately 12 kDa in all 66 strains of eubacteria examined, representing 27 different species. The 12 kDa protein was isolated by immunoaffinity chromatography. Subsequent preparative Western blotting enabled N-terminal amino acid sequence analysis by microsequencing. A high degree of amino acid sequence similarity with eubacterial ribosomal proteins L7/L12 was demonstrated. One of the mAbs (144,H-3) also cross-reacted in Western blotting with a 43 kDa protein, but only from streptococci. The 43 kDa protein carrying the common streptococcal epitope was isolated and sequenced in the N-terminal region. A high degree of amino acid sequence identity was found to elongation factor Ts from Escherichia coli.
authors.affiliation: National Institute of Public Health, Departments of Vaccinology, PO Box 4404 Torshov, N-0403 Oslo, Norway.
authors.forename: Jan
authors.initials: J
authors.lastname: Kolberg
authors.affiliation: National Institute of Public Health, Departments of Bacteriology, PO Box 4404 Torshov, N-0403 Oslo, Norway.
authors.forename: E Arne
authors.initials: EA
authors.lastname: Høiby
authors.affiliation: Biotechnology Centre of Oslo and Department of Biochemistry, University of Oslo, Gaustadailéen 21, N-0371 Oslo, Norway.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Lopez
authors.affiliation: Biotechnology Centre of Oslo and Department of Biochemistry, University of Oslo, Gaustadailéen 21, N-0371 Oslo, Norway.
authors.forename: Knut
authors.initials: K
authors.lastname: Sletten
mesh_terms: D000595:Amino Acid Sequence; D000907:Antibodies, Bacterial / Q000276:immunology*; D000911:Antibodies, Monoclonal / Q000276:immunology; D000918:Antibody Specificity; D015153:Blotting, Western; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes; D029968:Escherichia coli Proteins; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010445:Peptide Elongation Factors / Q000276:immunology*; D012269:Ribosomal Proteins / Q000276:immunology*; D017421:Sequence Analysis; D017386:Sequence Homology, Amino Acid; D013296:Streptococcus pneumoniae / Q000276:immunology*
chemical_list: D000907:Antibodies, Bacterial; D000911:Antibodies, Monoclonal; D000939:Epitopes; D029968:Escherichia coli Proteins; D010445:Peptide Elongation Factors; D012269:Ribosomal Proteins; C023512:elongation factor Ts; C512844:rplL protein, E coli; C016700:ribosomal protein L7-L12