A mutant from Escherichia coli which lacks ribosomal proteins S17 and L29 used to localize these two proteins on the ribosomal surface.

A mutant of Escherichia coli has been isolated which lacked ribosomal proteins S17 and L29, as judged by two-dimensional gel electrophoresis. A battery of immunological tests was used to confirm this result. Ribosomes of this mutant were used as a control for the localization of proteins S17 and L29 on the surface of the ribosomal subunits of E. coli. Protein S17 has been localized on the 30S subunit body, 3-5 nm away from the lower pole, while protein L29 is located at the back of the 50S particle on the opposite side to the interface.