Autotrophic diversity

This cycle represents the quantitatively most important C02 fixation pathway in Nature. It is found in most aerobic autotrophic organisms, ranging from diverse photosynthetic and chemolithoautotrophic bacteria to chloroplasts of eukaryotic algae and higher plants [5]. It is centered around carbohydrates, with ribulose 1,5-bisphosphate being the C02 acceptor (Figure 3.1). 

In the course of community development, the biomass and the production of autotrophic and heterotrophic organisms decrease [7]. Meanwhile, the correlation between the biodiversity and productivity of the communities is not yet clear and is still being discussed. The objective of this chapter is to consider the main results of the studies on species diversity in the Black Sea from the point of view of their interrelation to the production processes and to the ecological and physiological characteristics of the phytoplankton community. 

The carbon required by living organisms is an important constituent of cellular structure and metabolic compounds. This element is present in the environment in many forms. It may appear in simple form as gaseous carbon dioxide or as more complex organic compounds. Microorganisms are remarkably diverse in their carbon requirements and they are divided into two groups autotrophs and heterotrophs, based on their carbon source. 

Smorczewski, W. T., and Schmidt, E. L. (1991). Numbers, activities, and diversity of autotrophic ammonia-oxidizing bacteria in a fresh-water, eutrophic lake sediment. Canadian Journal of Microbi-ology 37, 828-833. 

The synthesis of acetyl-CoA by the Ljungdahl-Wood pathway of autotrophic carbon fixation in diverse bacteria and archaea is catalyzed by a Co- and Fe-containing corrinoid iron-sulfur protein (CoFeSP). This protein participates in the transfer of a methyl group from A -methyltetrahydrofolate to the cob(I)amide of CoFeSP to give a methylcob(III)amide, from which the methyl group is transferred to the reduced Ni-Ni-(4Fe-4S) active site cluster A of acetyl-CoA synthase (27). 

Wolfe RS (1980) Respiration in methanogenic bacteria. In Knowles CJ (ed) Diversity of bacterial respiratory systems vol I. CRC Press, Boca Raton, FL, pp 161-186 Wood HG, Ljungdahl LG (1991) Autotrophic character of the acetogenic bacteria. In Shively J-M, Barton LL (eds) Variations in autotrophic life. Academic Press, London, pp 201-250... 

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