Regulation of nitrogen fixation Questions & 100% Verified Answers | Latest Update | Already Graded A+

nif cluster a genetically linked and coordinately regulated group of operons encoding genes required for nitrogen fixation What is the EBP for nif genes? NifA How does the activity of NifA differ from that of NtrC? The unmodified form of NifA is active NtrC needs to be phosphorylated to be active Under what 2 conditions does nif transcription occur? 1) Only in the absence of a fixed nitrogen source 2) Only if oxygen concentration not high enough to damage nitrogenase 2 What are the 3 major operons associated with nitrogen fixation and what molecules do they assimilate? glnA - ammonium nas - nitrate nifA - nitrogen (via nitrogenase) Function of NifL - FAD-containing redox center - Required for sensing intracellular Oxygen conc - When oxidised: inhibits ATPase activity of AAA+ domain of NifA -- prevents transcription of nif genes