passages.id: split_6_test_1334_passage
passages.type: progene_text
passages.text: The functional equivalence between CLOSTRIDIUM : acetobutylicum sigma ( E ) and BACILLUS : subtilis sigma ( E ) was investigated by complementing a non - polar B. subtilis sigma ( E ) null mutant with the spoIIG operon from either B. subtilis ( spoIIG ( Bs ) ) or C. acetobutylicum ( spoIIG ( Ca ) ) .