passages.id: split_8_test_2917_passage
passages.type: progene_text
passages.text: We find that this region constitutes a complex operon with expression being controlled by three differentially regulated promoters : (i) csiDp , which affects the expression of all five genes , is cAMP - CRP / sigma S - dependent and activated exclusively upon carbon starvation and stationary phase ; (ii) gabDp1 , which is sigma S - dependent and exhibits multiple stress induction like sigma S itself ; and (iii) gabDp2 [ previously suggested by Schneider , B.L. , Ruback , S. , Kiupakis , A.K. , Kasbarian , H. , Pybus , C. , and Reitzer , L. ( 2002 ) J. Bacteriol. 184 : 6976-6986 ] , which appears to be Nac / sigma 70 - controlled and to respond to poor nitrogen sources .