transcriptional activator of the [[gene|75C568C8F6912AC064B8B435975D52510D25466A]]-[[gene|CAE38D8F25A5EC6AC8045E40072E6FEC632045FA]]-[[gene|8ABA3735067C7AA433E09F219EE7239196377A95]]-[[gene|F23B951F60A6A669D5BD86836906E0F4AD7A0C1B]]-[[gene|sacC ]]operon