Carbon photosynthetic fixation

Photosynthetic carbon fixation and oxidation of a reduced sulfur compound in Anoxyphotobacteria are stoichiometrically linked by van Niel s equations (12.1) ... 

This set of reactions is very detrimental to the efficiency of photosynthesis. Oxygen is added to carbon, CO2 is lost, energy is consumed, and ribulose bisphosphate is destroyed. For a plant to be able to increase the discrimination of Rubisco for CO2 would obviously be advantageous, but that hasn t happened, either naturally or through the efforts of scientists. An increased concentration of CO2 in the atmosphere may lead to increased photosynthesis and decreased photorespiration, but high CO2 concentrations would also contribute to global warming (and the increased photosynthetic carbon fixation would not likely reduce the amount of CO2 in any event). 

It is assumed that the reaction catalyzed by RubisCO is a rate-limiting step in reactions of photosynthetic carbon fixation expressed as follows in the lump ... 

Robinson DH, Arrigo KR, DiTullio GR, Lizotte MP (2003) Evaluating photosynthetic carbon fixation during Phaeocystis antarctica blooms. In DiTullio GR, Dunbar RB (eds) Biogeochemistry of the Ross Sea. Antarct Res Ser 78 77-91... 

Are they a form of carbonic anhydrase Carbonic anhydrases (CAs) play an important role in photosynthetic carbon fixation, converting HC03 (aq) in seawater to CO2. It is possible that the copper complexes of these peptides perform this function. Evidence from the studies by van den Brenk et al show that patellamide D (4) forms [PatDH + Cu2 + C02]" and [PatDHa + Cui + COa] complexes in the mass spectrometer lending credence to this proposal. 

Barnes, D.J. and Taylor, D.L., 1973. In situ studies of calcification and photosynthetic carbon fixation in the coral Montastrea annularis. Helgol. Wiss. Meeresunters., 24 284-291. 

US biochemist Melvin Calvin (1911-97) publishes details of the photosynthetic carbon-fixation cycle (Calvin cycle). 

Schultz, G. and Schulze-Siebert, Chloroplast isoprenoid synthesis in spinach and barley Direct intermediate supply by photosynthetic carbon fixation, in Biological Role of Plant Lipids (P. 

One of the most extensively studied biological isotope fractionation process is the photosynthetic carbon fixation (O Leary 1981 Rundel et al. 1988 Ivlev 2001). It was found that plants with C3 (e.g., rice, beet, potatoes, wheat, barley, legumes), C4 (e.g., com, sugar cane, sorghum. 

Marine diatoms are major contributors to coastal and oceanic primary productivity. Assimilation of nitrate, the predominant limiting nutrient, is usually tightly coupled to photosynthetic carbon fixation however, during darkness or periods of rapid nitrate assimilation, stored carbon reserves are respired for the energetic requirements of the cell and for protein synthesis (Turpin and Weger 1990). 

Ryther, J. H., and D. W. Menzel. 1965. Comparison of the C-technique with direct measurement of photosynthetic carbon fixation. Limnol. Oceanogr. 10(3) 490-492. 

Black, C. C. Photosynthetic carbon fixation in relation to net CO2 uptake. Ann. Rev. Plant Physiol. 24,253-286 (1973)... 

Trench, R. K., Boyle, J. E. and Smith, D. C. (1973) The association between chloroplasts of Codium fragile and the mollusc Elysia viridis. I. Characteristics of isolated Codium chloroplasts. II. Chloroplast ultrastructure and photosynthetic carbon fixation in E. viridis. Proc. R. Soc. Land. B, 184, 51-61, 63-81. 

An external site of synthesis of PEP from photosynthetically formed 3-PGA can be detected by rising the P. concentration up to 5 mM and adding exogenously excessive amounts of rabbit PGM and enolase to intact chloroplasts (10 and 2.5 units/50 ug chlorophyll) similar as in /42/. The activity of the shikimate pathway (measured as nmol Phe and Tyr formed) was considerably enhanced as a result of supply of high amounts of PEP by this enzyme reaction and re-import by the phosphate translocator. Consequently, this way might be considered as an additional site of supply optimized under in vitro conditions by adding enzymes in excess. Under in vivo conditions, the carbon flow from triosephosphates of photosynthetic carbon fixation is preponderantly directed to sucrose synthesis /43/ and less to PEP. 

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