fIhDC, but not fleQ, regulates flagella biogenesis in Azotobacter vinelandii, and is under AIgU and CydR negative control.

The article reports on flhDC as a regulator of flagella biogenesis in Azotobacter vinelandii. It is said that Azotobacter vinelandii is a nitrogen-fixing soil bacterium that undergoes differentiation to form cysts resistant to desiccation. Upon encystment, it is said that this bacterium becomes non-motile. As in enteric bacteria, motility in A. vinelandii occurs through the use of peritrichous flagella. According to the article, the FlhDC proteins are the master regulators of flagella and motility in enterobacteria, whereas FleQ is the master regulator in P. aeruginosa and it is under AlgU (sigmaE) negative control. It is suggested that there is an existence of a cascade consisting of AlgU and CydR that negatively controls expression of flhDC.