Prokaryotes photosynthesis

Bryant, D.A., Fiigaard, N.-U., 2006. Prokaryotic photosynthesis and phototrophy illuminated. Trends in Microhiology 14, 488—496. 

Cyanobacteria, prokaryotic algae that perform oxygenic photosynthesis, respond to a decrease in ambient growth temperature by desaturating the fatty acids of membrane lipids to compensate for the decrease in the molecular motion of the membrane lipids at low temperatures. During low-temperature acclimation of cyanobacterial cells, the desaturation of fatty acids occurs without de novo synthesis of fatty acids [110, 111]. All known cyanobacterial desaturases are intrinsic membrane proteins that act on acyl-Hpid substrates. 

Prokaryote heterotrophs precursors of cyanobacteria. Stromatolites. Sulfur bacteria Beginning of photosynthesis Traces... 

This article elucidates molecular mechanisms in light perception, stimulus transformation and signal transmission in photosynthetic prokaryotes. Special emphasis is put on the distinction between various coupling between different light responses and photosynthesis. 

Fig. 2. An evolution diagram illustrating a suggestion of common ancestry of some present-day organisms. The essential features of present-day photosynthesis may have originated in the prebiotic era and is preserved in its most primitive form in (at least some) present-day phototrophs. The heterotrophs may have developed parallel with the aerobic nonphotosynthetic bacteria, some l to 1.5 x 109 years after the emergence of the cyanobacteria. The eukaryotic photosynthetic organisms developed much later, perhaps some 1.5 to 0.5 x 109 years ago. The archaebacteria are primitive organisms that seem to have no evolutionary relation with the present prokaryotes.21 Little is known about their energy metabolism. Tentatively, they are considered as a very early form of cellular life.

Life on earth started anaerobically and anaerobic organisms flourished for more than 500 million years before oxygen became available and started to play a role in the further evolution of life (Fenchel and Finlay 1994). The evolution of photosynthesis in cyanobacteria resulted in a steady increase in the amount of oxygen in the atmosphere. This presence of oxygen opened new ways for the degradation of substrates and resulted in the evolution of aerobic energy metabolism, i.e. production of ATP. Many prokaryotes use oxygen... 

One of the more exciting and recent advances in the field of plant biochemistry has been the discovery of the mevalonate-independent pathway for the biosynthesis of isoprenoids (Fig. 10.4). This new pathway, referred to a the methyl-erythritol-phosphate or MEP pathway for the first intermediate committed solely to the biosynthesis of isoprenoids, was first discovered in prokaryotes capable of accumulating hopenes, the equivalent of eukaryotic sterols. 6,17 The MEP pathway has since been confirmed in plants and, not surprisingly, has been localized to chloroplasts.18 Operation of the MEP pathway is intimately related to the reactions of CO2 fixation and photosynthesis, as evidenced by the two immediate precursors pyruvate and phosphoglyceraldehyde for this pathway. Two important features of this pathway are that mevalonate is not an intermediate in the plastidic synthesis of isopentenyl (IPP) and dimethylallyl diphosphate, (DMAPP), and this pathway... 

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