Metabolic Pathways of Bacterial Nitrification 



399 



4jg 



NITROGEN 



NITRITE 

 NITRATE 



60 



MINUTES 



Fig. 1. Nitrogen balance in Nitrobacter agiUs extracts. Reaction vessel 



contained extiact nitrogen, 0.28 mg; K-HPOj, 100 /imoles; and 5 jumoles 



of FeCL and nitrite in 5.0 ml. 



20 180 



MINUTES 



Fig. 2. Utilization of O^ by Nitrobacter agilis extracts in the presence of 

 various concentrations of nitrite. The Warburg vessel contained nitrite, 50 

 jumoles of K0HPO4, 5 //.moles of FeS04 and sufficient extract to give 0.28 

 mg. total nitrogen. The final xolume was 3.0 ml. nitrite supplied at con- 

 centrations of 5, 25, and 250 (imoles per flask. 



