Regulation of dipicolinic acid biosynthesis in sporulating Bacillus cereus. Characterization of enzymic changes and analysis of mutants.

摘要: Some of the early enzymes in lysine-biosynthetic pathway also function for dipicolinic acid synthesis sporulating Bacillus cereus T. 1. The first enzyme, aspartokinase, loses its sensitivity to feedback inhibition by lysing. This change occurs before time but at a when diaminopimelic is required spore cortex formation. 2. A possible regulatory branch point was studied examining properties key dihydrodipicolinic reductase. No alteration or sedimentation rate this enzyme could be detected during sporulation. 3. Two mutants producing heat-sensitive spores were analysed. Both produced that contained decreased amounts acid. Although neither lysine auxotroph, they both had greatly activities certain cells. 4. Starvation cells calcium results production are and contain less than control. content one enzymes, synthetase, calcium-starved account lower concentration spores.