FIG. 1.

The phosphorelay that controls the sporulation in Bacillus subtilis. Five different histidine kinases are known to be involved in processing the signals. Histidine kinases have a signal detection domain and an autokinase domain which can be subdivided into a phosphotransferase domain and an ATP binding domain. The histidine kinases pass on the phosphoryl group to Spo0F. From Spo0F, it is transferred to the transcription factor Spo0A through Spo0B. The flow of the phosphoryl group is as follows: His→Asp→His→Asp.