text: In Rhodospirillum rubrum, a gene encoding the key enzyme in this process is inactivated by ADP- ribosylation of a arginine-101.
full_question: In Rhodospirillum rubrum, a gene encoding the key enzyme in this process is inactivated by ADP- ribosylation of a arginine-101. In the structures where this biochemical process takes place, Nod factors induce the production of the oxygen-carrier leghemoglobin. Sixteen equivalents of ATP are hydrolyzed in this process, which produces one molecule of hydrogen gas. This process requires a cofactor containing iron and (*) molybdenum atoms. This process has a very high activation energy because it requires cleaving a triple bond. Diazotrophs perform this process, the best-studied example of which is done by Rhizobia at root nodules. For 10 points, name this process of producing ammonia from the most abundant gas in the atmosphere.
first_sentence: In Rhodospirillum rubrum, a gene encoding the key enzyme in this process is inactivated by ADP- ribosylation of a arginine-101.
raw_answer: nitrogen fixation