We found that Rob ( i ) activates the transcription of zwf , fpr , fumC , micF , nfo , and sodA , ( ii ) requires a 21-bp soxbox-marbox-robbox sequence to activate zwf transcription , ( iii ) protects the soxbox/marbox/robbox from attack by DNase I , ( iv ) is ambidextrous , i. e. , requires the C-terminal domain of the a subunit of RNA polymerase for activation of zwf but not fumC or micF , ( v ) bends zwf and fumC DNA , and ( vi ) binds zwf and fumC DNA as a monomer .