Assimilates of carbon

Significant differences in net photosynthetic assimilation of carbon dioxide are apparent between C, C, and CAM biomass species. One of the principal reasons for the generally lower yields of C biomass is its higher rate of photorespiration if the photorespiration rate could be reduced, the net yield of biomass would increase. Considerable research is in progress (ca 1992) to achieve this rate reduction by chemical and genetic methods, but as yet, only limited yield improvements have been made. Such an achievement with C biomass would be expected to be very beneficial for foodstuff production and biomass energy appHcations. 

Weinhouse, S., and K. F. Lewis Assimilation of Carbon Dioxide in Oxalate... 

The photoreductive synthetic process that promotes the assimilation of carbon dioxide into carbohydrates, other reduced metabolites, as well as ATP (synthesis of the latter is termed photophosphorylation). Photosynthesis is the primary mechanism for transducing solar energy into biomass, and green plants utilize chlorophyll a to capture a broad spectrum of solar radiant energy reaching the Earth s surface. Photosynthetic bacteria typically produce NADPH, the reductive energy of which is converted to ATP. 

Figure 23-36 Some control mechanisms for photosynthetic assimilation of carbon dioxide. After Buchanan and Schur-mann424 with modifications.

Estimates of modeled parameters of particular oceanic processes of the carbon cycle range widely. For instance, from the data of various authors the estimates of assimilation of carbon from the hydrosphere in the process of photosynthesis range from 10 GtC/yr to 155 GtC/yr. The value 127.8 GtC/yr is most widely used. However, because of large variations in these estimates, calculation of the C31 coefficient is fraught with great uncertainty therefore, specifying it requires numerical experiments using other, more accurate data. 

The role of vegetation in assimilation of carbon dioxide from the atmosphere... 

Brown, H.T., and Escombe, F. 1900. Static diffusion of gases and liquids in relation to the assimilation of carbon and translocation in plants. Philos. Trails. Roy. Soc. London, Ser. B 193 223-291. 

J.W. Foster, S.F. Carlson, S. Ruben and M.D. Kamen, Radioactive Carbon as an Indicator of Carbon Dioxide Reduction. VII. The Assimilation of Carbon Dioxide, Proceedings of the National Academy of Sciences 27, 590-596, 1941. 

Tuttle J. H. and Jannasch H. W. (1977) Thiosulfate stimulation of dark assimilation of carbon dioxide in shallow marine environments. Microb. Ecol. 4, 9-25. 

Fig.2.7 Assimilation of carbon dioxide. The key reaction of the dark reaction is the assimilation of carbon dioxide by ribulose l 5-bisphosphate carboxylase (Simplified from Fig. 26-31 in Biochemistry. L. Stryer, 4th Ed. 1995. W.H. Freeman Co., New York)...

Doman, N.G., L.N. Khadzhi-Murat, and S.E. Demina Unity and individual path assimilation of carbon by different types of plants Doklady Akademii Nauk SSSR 122 (1958) 171-174. 

The carbon cycle in seas involves the assimilation of carbon dioxide dissolved in sea water by the phytoplankton with a simultaneous oxygen release. Zooplankton and fish use this oxygen for the respiration. During the organic matter decomposition, CO2 is supplied into the atmosphere. On land, the exchange of carbon dioxide with the atmosphere is accomplished by respiration, photosynthesis and by the combustion of fossil fuels. 

The biological isotopic fractionation occurring during assimilation of carbon by the marine biosphere (Sp) depends on the partial pressure of CO2 dissolved in sea water, itself directly related to the... 

The two principal reactions, assimilation of carbon and oxidation of nitrogen, are intimately connected. Winogradski, in fact, has established that, in this kind of fermentation, for r g. of carbon assimilated there are about 36 g. of nitrogen oxidized ... 

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