Nitrate respiration nature

Finlay BJ, Span ASW, Harman JM (1983) Nitrate respiration in primitive eukaryotes. Nature... 

Hentschel U, Felbeck H. Nitrate respiration in the hydrothermal 62. vent tubeworm Riftia pachyptila. Nature 1993 366 338-340. 

From the data of Figure 12, it is clear that the addition of nitrate had comparable effects on heat dissipation under aerobic conditions as well. This result is consistent with the properties of nitrate respiration previously described and its constitutive nature in these symbionts [138]. At nitrate concentrations between 0.5 and 5 mmol 1 , the total heat production was increased 2-fold relative to the unstimulated anoxic baseline. Thus, nitrate respiration makes a distinctly measurable contribution to the energy flow of the gill. The symbiosis of L aequizonata was particularly useful for establishing this point, because of the ability to distinguish between animal tissue metabolism and symbiont... 

Explain how the CO2 content and pH of natural waters is affected by processes and reactions including the dissolution of C02(g), photosynthesis and respiration, aerobic decay, anaerobic decay (fermentation), nitrate reduction, and denitrification and sulfate reduction. 

Certain species of Enterobacteriaceae, especially 0. proteus, could utilise nitrates as electron acceptors for anaerobic respiration, resulting in reduction of nitrate into nitrite. Nitrite further could possibly react with secondary amines present in the wort, forming (V-nitrosoamine (Figure 8.2). A -nitrosomines are carcinogenic in nature (Smith, 1994). Hence, a considerable amount of apparent total N-nitroso compounds (ATNCs) represents a possible risk to health, and consequently their concentration is strictly monitored and limited to 20 gg/1 (Maiguerite and Walker, 2002). Because of the risk of W-nitroso compounds, the Enterobacteriaceae species related to brewery environments are monitored. 

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