title: Monoclonal antibodies to Escherichia coli 50S ribosomes.
abstract: Hybridoma cell lines that produce monoclonal antibodies directed against 50S Ribosomal proteins have been isolated. Spleen cells (from BALB/c mice immunized with 50S ribosomal subunits extracted from Escherichia coli) were fused to mouse myeloma cell line SP2/O-Ag 14. The initial screening for antibody producing hybridomas was carried out by a double antibody sandwich method; hybridomas were subsequently cloned in soft agar. Antibodies were characterized by their specific binding to individual 50S ribsomal proteins separated on phosphocellulose columns and in two-dimensional polyacrylamide gels. The assignments were confirmed with purified single ribosomal proteins. Of four clones analyzed thus far, two are identical with specificity for r-protein L5. The other clones produce two different antibodies directed against r-protein L20. Each monoclonal antibody formed ribosome dimers visualizable in the electron microscope. Dimers could be reacted with a different second antibody to form chains containing 8 or more ribosomes, which may be useful for structural studies.
mesh_terms: D000818:Animals; D000906:Antibodies; D002460:Cell Line; D000939:Epitopes; D004926:Escherichia coli / Q000032:analysis*; D006822:Hybrid Cells / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D008970:Molecular Weight; D010954:Plasmacytoma; D012269:Ribosomal Proteins / Q000032:analysis* / Q000276:immunology; D012270:Ribosomes / Q000032:analysis*; D013154:Spleen / Q000276:immunology
chemical_list: D000906:Antibodies; D000939:Epitopes; D012269:Ribosomal Proteins