A strain of Escherichia coli which gives rise to mutations in a large number of ribosomal proteins

Abstract

A strain of E. coli K12 has been isolated which gives rise to mutations in a large number of ribosomal proteins. Mutant VT, which was derived from A19, shows a novel type of streptomycin dependence and has an altered ribosomal protein S8. Streptomycin-independent isolates from mutant VT contain a great variety of changed proteins on two-dimensional polyacrylamide gels. 120 revertants screened in this way have changes in thirteen 30S proteins and fifteen 50S proteins. Several mutants were found in which additional proteins are present on the ribosome. Further, there is one instance of a ribosomal protein (L1) being absent, and one of apparent doubling of a ribosomal protein (L7/12). The unique properties of mutant VT probably are the result of the altered S8.