Nitrogen isotopes fractionations

Delwiche, C.C. and Steyn, P.L. 1970 Nitrogen isotope fractionation in soils and microbial reactions. Environmental Science and Technology 4 929-935. 

Mariotti, A., Mariotti, F., Champigny, M.L., Amarger, N. and Moyse, A. 1982 Nitrogen isotope fractionation associated with nitrate reductase activity and uptake of NO3by pearl millet. Plant Physiology 69 880-884. 

Now, GC-IRMS can be used to measure the nitrogen isotopic composition of individual compounds [657]. Measurement of nitrogen isotope ratios was described by Merritt and Hayes [639], who modified a GC-C-IRMS system by including a reduction reactor (Cu wire) between the combustion furnace and the IRMS, for reduction of nitrogen oxides and removal of oxygen. Preston and Slater [658] have described a less complex approach which provides useful data at lower precision. Similar approaches have been described by Brand et al. [657] and Metges et al. [659]. More recently Macko et al. [660] have described a procedure, which permits GC-IRMS determination of 15N/14N ratios in nanomole quantities of amino acid enantiomers with precision of 0.3-0.4%o. A key step was optimization of the acylation step with minimal nitrogen isotope fractionation [660]. 

Jensen ML, Nakai N (1962) Sulfur isotope meteorite standards, results and recommendations. In Jensen ML (ed) Biogeochemistry of sulfur isotopes, NSE Symp Vol, p 31 Jia Y (2006) Nitrogen isotope fractionations during progressive metamorphism a case study from the Paleozoic Cooma metasedimentary complex, southeastern Australia, Geochim Cosmochim Acta 70 5201-5214... 

Shearer, G., and Kohl, D. H. (1988). Nitrogen isotope fractionation and "O exchange in relation to the mechanism of denitrification of nitrite by Pseudomonas stutzeri. J. Biol. Chem. 263, 13231-13245. 

Hofstetter T. B. Neumann A. Arnold W. A. Hartenbach A. E. Bolotin J. Cramer C. J. Schwarzenbach R. P. Substituent effects on nitrogen isotope fractionation during abiotic reduction of nitroaromatic compounds. Environ. Sci. Technol. 2008, 42, 1997-2003. 

Montoya, J.P. (1994) Nitrogen isotope fractionation in the modern ocean implications for the sedimentary record. In Carbon Cycling in the Glacial Ocean Constraints on the Ocean s Role in Global Change (Zahn, R., Pedersen, T.F., Kaminski, M.A., and Labeyrie, L., eds.), pp. 259-280, Springe, Berlin. 

Wada, E. (1980) Nitrogen isotope fractionation and its significance in biogeochemical processes occurring in marine environments. In Isotope Marine Chemistry (Goldberg, E.D., Horibe, Y., and Saruhashi, K., eds.), pp. 375-398, Uchida Rokakudo, Tokyo. 

McCarthy, M. D., Benner, R., Lee, C., and Fogel, M. L. (2007). Amino acid nitrogen isotopic fractionation patterns as indicators of heterotrophy in plankton, particulate, and dissolved organic matter. Geochimica et Cosmochimica Acta 71, 4727-4744. 

Delwiche, C. C., and Steyn, P. L. (1970). Nitrogen Isotope Fractionation In Soils And Microbial Reactions. Environmental Science Technology 4, 929. 

Montoya, J. P., and McCarthy, J. J. (1995). Nitrogen isotope fractionation during nitrate uptake by marine phytoplankton in continuous culture. J. Plankton R S. 17(3), 439—464. 

Waser, N. A. D., Harrison, P. J., Nielsen, B., Calvert, S. E., and Turpin, D. H. (1998b). Nitrogen isotope fractionation during the uptake and assimilation of nitrate, nitrite, ammonium, and urea by a marine diatom. Limnol. Oceanogr. 43(2), 215—224. 

Figure 34.3 Nitrogen isotopic fractionation processes. The vectors approximate the isotopic changes associated with the indicated addition or removal of nitrogen from an initial nitrate pool with a of 5%o (black filled circle). Note that the fractionating processes (water column deni-...

Needoba, J. A., and Harrison, P. J. (2004). Influence of low light and a light Dark cycle on N03 uptake, intracellular NOs , and nitrogen isotope fractionation by marine phytoplankton. J. Phycol. 

Beaumont V. I., Jahnke L. L., and Des Marais D. J. (2000) Nitrogen isotopic fractionation in the synthesis of photosynthetic pigments in Rhodobacter capsulatus and Anabaena cylindrica. Org. Geochem. 31(11), 1075-1085. 

Cook, F.D., Wellman, R.P. and Krouse, H.R., 1973. Nitrogen isotope fractionation in the nitrogen cycle. Proceedings of the Symposium on Hydrochemistry and Biogeochemistry, Tokyo, Japan, Biogeochemistry, Vol. 2. Clarke Co., Washington, DC, pp. 49— 64. 

Wellman, R.P., 1969. Nitrogen Isotope Fractionation in Chemical and Microbiological Systems. Ph.D. Thesis, University of Alberta, Edmonton, Canada, 159 pp. 

Stable isotopes of each of these elements have played important roles in elucidation of their chemistries. Specifically, and have been used as stable tracers for research on N-chemistry dealing with food and fiber production, metabolic pathways, and environmental control. Their value is ultimately limited because macroscopic amounts of carrier often exceed in situ concentrations (and therefore influence the biochemistry), and natural nitrogen isotope fractionation leads to variances in natural abundance. Nevertheless, stable tracers have been used effectively in many studies, including foflowing N-cycle processes in soils (1) and unraveling metabolic pathways (2,3). 

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