Bacterial transcription factor. Molecular model of the transcription factor AmrZ from the bacterium Pseudomonas aeruginosa complexed with DNA (deoxyribonucleic acid).Transcription factors are proteins that bind to specific sequences of DNA and control the transcription (transfer) of genetic information from DNA to RNA (ribonucleic acid). AmrZ acts as an activator and repressor for bacterial virulence factors. Expression of the virulence factors leads to chronic infections and a poorer prognosis.