Identification of Neighbouring Proteins in the Ribosomes of Escherichia coli. A Topographical Study with the Cross-Linking Reagent Dimethyl Suberimidate

Abstract

Treatment of both the 30-S and 50-S ribosomal subunits of Escherichia coli with dimethyl suberimidate, a cross-linking agent specific for protein amino groups, resulted in the formation of new protein species detectable by acrylamide gel electrophoresis in sodium dodecylsulfate. These new species were shown to contain two or more ribosomal proteins linked together and, after cleaving the cross-links with ammonia, these constituents were identified by two-dimensional electrophoresis.