A new gene in E. coli RNA synthesis.

A novel spontaneous temperature sensitive mutant of Escherichia coli, which stops synthesizing stable RNA and some proteins immediately upon temperature shift from 30 degrees C to 42 degrees C, is described. Stable RNA species are not preferentially degraded in the mutant at the nonpermissive temperature. The guanine polyphosphate compounds, ppGpp (MS1) and pppGpp (MS2), are not produced at 42 degrees C. The mutant strain does not grow at 42 degrees C in either broth or defined minimal medium supplemented with any of a variety of carbon sources. The temperature sensitive mutation in this strain maps between dap A, E and pts I and defines a new locus affecting RNA synthesis in E. coli.