ESPM 165 Lecture Notes - Femoco, Nitrifying Bacteria, Nitrogen Fixation

• School: Berkeley
• Department: Environmental Science, Policy, And Management
• Course: ESPM 165
• Professor: claudia carr

Document Summary

The trouble with nitrogen: very stable, inert, can"t be used by most of life. Mostly in nucleic acids and proteins, but also in cofactors, small hormones, neurotransmittiers, pigments, defense chemicals. Bacteria oxidize ammonia into nitrite and nitrate: denitrification. Nitrate is reduced to n2 under anaerobic conditions. No3- is the ultimate electron acceptor instead of o2: assimilation. Plants and microorganisms reduce no2- and no3- to nh3 via nitrite reductases and nitrate reductases. Nitrifying bacteria again convert nh3 to nitrite and nitrate. The structure of nitrogenase is known other details are not: femo co-factor one variant substitutes vanadium for mo, atp hydrolysis mechanically coupled to catalysis. Rhizobia fix nitrogen in symbiotic root nodules: root nodules, bacteria are fed by plant and o2 conc. Recall the critical n-containing reactions: amino transferases (glutamate) intracellular storage molecule for nitrogen, amido transferases (glutamine) important intermediate for transfer of amine group to a variety of downstream targets.