Chromosomal regions which control sporulation in Bacillus subtilis

Large quantities of sporulation mutants have been isolated with a variety of mutagens. The genetic sites for asporogeny have been localized on the chromosome of Bacillus subtilis through transduction with phage PBSI. Through these procedures specific portions of the chromosome which are associated with sporulation have been identified. Although asporogenic (Sp−) defects were observed to be scattered throughout the four linkage groups of the genetic map of B. subtilis, only three extensive Sp− linkage groups were identified. The first linkage group of Sp− markers is located at the proximal end of the chromosome between the cys A and ery markers. The second cluster of spore genes mapped to the right of ura, and the third linkage group of spore markers mapped to the left of lys-2. Defects within specific regions of the first and third spore gene clusters obstructed some early products of sporogenesis.