What are the conditions necessary for fixation of atmospheric nitrogen by Rhizobium? What is their role in N2-fixation? Question asked by: Emily Emily2 1 Answer ActiveVotedNewestOldest 0 maya presence of the enzyme nitrogenase presence of leg-heomoglobin Non-haem iron protein, ferrodoxin as the electron-carrier constant supply of ATP Emily approved August 13, 2017 Write your answer. Register or Login