6027
To investigate regulatory networks in Legionella pneumophila , the gene encoding the homolog of the Escherichia coli stress and stationary-phase sigma factor RpoS was identified by complementation of an E. coli rpoS mutation .
 ( protein: RpoS, None) , ( DNA: rpoS, None) , ( protein: Escherichia coli stress and stationary-phase sigma factor, None) 
Locate the role in the text that participated in the event based on the event type and return it in the event list. 
 Option: Event type: RNA,cell type,protein,cell line,DNA, Arguments type: . 
Text: {0} 
Answer:
 ( protein: RpoS, None) , ( DNA: rpoS, None) , ( protein: Escherichia coli stress and stationary-phase sigma factor, None) 