Genetic analysis of ribonucleic acid polymerase mutants of Bacillus subtilis

Deoxyribonucleic acid-dependent ribonucleic acid polymerase mutants of Bacillus subtilis strain Marburg were isolated after mutagenesis of spores with ethyl methane sulfonate. Genetic analysis by PBS1-mediated transduction and by transformation indicated that mutations responsible for all of the four phenotypic classes studied (rifampin resistance, streptovaricin resistance, streptolydigin resistance, and temperature sensitivity) were clustered close to the cysA14 locus. Three-factor transformation analysis has indicated the most probable marker order as follows: Rif(R)(Stv)(R)-Std(R)-Ts(418)-Ts(427). In addition, further characterization of the classical group I reference marker, cysA14, is reported.