SporeWeb

SigH Onset of sporulation – (Stage I - II)

SigH during the onset of sporulation

The most important role of σ^H in the sporulation process is to establish a positive feedback loop that results in accumulated levels of Spo0A~P ⁶² The σ^H regulon furthermore encompasses genes of which the products are required for the transition from exponential growth to stationary phase, with a subset of genes required specifically for sporulation ⁶³. Many of these genes are co-regulated by other sigma factors or regulators, like σ^A and Spo0A.

The posttranslational regulation of σ^H is complex, with its levels and activity depending on several internal factors such as acid levels and the degree of ATP-dependent protease activity ^{59, 60, 61}.