passages.id: split_7_validation_584_passage
passages.type: progene_text
passages.text: sigmaF is controlled by a regulatory cascade involving an anti - sigma factor , SpoIIAB , an anti - anti - sigma factor , SpoIIAA , and a membrane - bound phosphatase , SpoIIE , which converts the inactive , phosphorylated form of SpoIIAA back to the active form .