Ribosomal proteins cross-linked to peptide chain termination release factor 2.

The peptide chain termination factor 2 (RF2) was covalently linked to Escherichia coli ribosomal proteins with the bifunctional reagent, dimethyl suberimidate. Ribosomal RF2 complexes were identified by immunological and radioimmunological techniques which utilized both antibody specific for individual ribosomal proteins and also for RF2. Efficient cross-linking occurred with proteins L2, L7/L12, and L11 of the large ribosome subunit and to a lesser extent with S6, S17, and S18 of the small subunit. On the basis of these and other data the ribosomal binding domain of RF2 appears to be a small region at the interface between the 30 S and 50 S subunits involving parts of both subunits.