Nitrogen metabolism in cyanobacteria

Bothe, H., Schmitz, O., Yates, M.G., Newton, W.E., 2010. Nitrogen fixation and hydrogen metabolism in cyanobacteria. Microbiology and Molecular Biology Reviews 74,529—551. 

Flores, E., andHerrero, A. (1994). Assimilatory nitrogen metabolism and its regulation. In The Molecular Biology of Cyanobacteria (Bryant, D., ed.). Kluwer, Dordrecht, The Netherlands, pp. 487-517. 

Much of the N-metabohsm of marine cyanobacteria observes the same basic scheme as that known for widely studied freshwater species (see Flores and Herrero 1994 Herrero et al., 2001 for reviews). Nitrogen acquisition and metabolism in marine cyanobacteria are finely tuned to photosynthetic activity, the availability of additional nutrients, and other environmental factors. Most, if not all, of N-metabolism is funnelled through the GS—GOGAT pathway which—on balance—links ammonium... 

Florencio, F. J., Marques, S., and Candau, P. (1987). Identification and characterization of a glutamate dehydrogenase in the unicellular cyanobacterium Synechocystis PCC 6803. FEBS Lett. 223, 37-41. Flores, E., and Herrero, A. (1994). Assimmilatory nitrogen metabolism and its regulation. In The Molecular Biology of Cyanobacteria (Bryant, D. A., ed.). Kluwer Academic, Dordrect, The Netherlands, pp. 487-517. 

R.P. Sinha, H.D. Kumar, A. Kumar, D.-P. Hader (1995). Effects of UV-B irradiation on growth, survival, pigmentation and nitrogen metabolism enzymes in cyanobacteria. Acta ProtozooL, 34,187-192. 

Cyanobacteria may possess several enzymes directly involved in H2 metabolism nitrogenase(s) catalyzing the production of H2 concomitantly with the reduction of nitrogen to ammonia, an uptake hydrogenase, catalyzing the consumption of H2 produced by the nitrogenase, and a bidirectional hydrogenase, which has the capacity to both take up and produce H2 [3, 5],... 

Iron is concentrated most by cyanobacteria followed closely by phytoplankton (Jones et al., 1978) 7S). Copper is concentrated most by phytoplankton and next by cyanobacteria. Primitive photosynthesizers such as the cyanobacteria are especially rich in non-heme iron, which is involved in the reduction of C02, molecular nitrogen and many other substances. It has been speculated that during the evolution of the plant kingdom, the ratio of iron to other polyvalent metals decreased because the latter became more and more involved in metabolism, chiefly in oxidation reactions in the cells (Ochiai, 1983)76). Therefore, cyanobacteria contain much more iron than other plants. It has been also concluded from analyses of individual fossils that the evolution of different algal groupings in the Precambrian was accompanied by a decrease in the iron content and simultaneous enrichment in copper and others (Udel nova et al., 1981)77). Copper has been interpreted to be a marker element of the younger Proterozoic as far as its biological association is concerned. Thus, the two elements iron and copper cover the important period of the Earth s history, between 3.8 — 1.5 and 1.5 — 0.6 Ga resp. (Ochiai, 1983)76>. 

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