passages.id: split_8_test_3543_passage
passages.type: progene_text
passages.text: To test the model in which the K356E and H359R substitutions in sigmaA interfere with the interaction of Spo0A and sigmaA , we examined the effects of alanine substitutions at these positions in sigmaA on sigmaA 's ability to direct transcription in vivo and in vitro .