Homology between Drosophila melanogaster and Escherichia coli ribosomal proteins

Antibodies raised against D. melanogaster ribosomal proteins were used to examine possible structural relationships between eukaryotic and prokaryotic ribosomal proteins. The antisera were raised against either groups of ribosomal proteins or purified individual ribosomal proteins from D. melanogaster. The specificity of each antiserum was confirmed and the identity of the homologous E. coli ribosomal protein was determined by immunochemical methods. Immuno-overlay assays indicated that the antiserum against the D. melanogaster small subunit protein S14 (anti-S14) was highly specific for protein S14. In addition, anti-S14 showed a cross-reaction with total E. coli ribosomal proteins in Ouchterlony double immunodiffusion assays and with only E. coli protein S6 in immuno-overlay assays. From these and other experiments with adsorption of anti-S14 with individual purified proteins, the E. coli protein homologous to the D. melanogaster protein S14 was established as protein S6.