Bacteria phototrophs

Most important in the classification of sulfur bacteria is the distinction between phototrophic and chemotrophic sulfur bacteria. Phototrophic (purple or green) bacteria use light as energy source to reduce CO2 to carbohydrates. Reduced sulfur compounds are used as an electron donor for this reduction, which takes place under anaerobic conditions. The oxidation reactions of sulfide to sulfur and sulfate by phototrophic bacteria are called the Van Niel reactions ... 

Algae carotenogenesis carotenoid chemotaxonomy cyanobacteria green sulfur bacteria phototroph purple bacteria... 

All photosynthetic cells contain some form of photosystem. Photosynthetic bacteria, unlike cyanobacteria and eukaryotic phototrophs, have only one photosystem. Interestingly, bacterial photosystems resemble eukaryotic PSII more than PSI, even though photosynthetic bacteria lack Og-evolving capacity. 

Phototrophic Bacteria and Their Sulfur Metabolism (H. G. Triiper)... 

Novak RT, RF Gritzer, ER Leadbetter, W Godchaux (2004) Phototrophic utilization of taurine by the purple nonsulfur bacteria Rhodopseudomonas palustris and Rhodobacter sphaeroides. Microbiology (UK) 150 1881-1891. 

Bacteria Using Nitrate Electron Acceptor under Anaerobic Conditions, and Anaerobic Phototrophs... 

Aside from C. vinosum, type III-PHA synthases have so far been detected exclusively in the phototrophic purple sulfur bacteria such as Thiocystis viol-acea [51] and Thiocapsa pfennigii [26, 57] and in cyanobacteria such as Synechocystis sp. PCC6803 [49] or Synechococcus sp. MAI 9 [58]. In contrast, the photosynthetic nonsulfur purple bacteria possess type I-PHA synthases. 

A great variety of light-triggered processes exists even in phototrophic prokaryotes (photosynthetic bacteria, Cyanobacteria = Cyanophyceae = blue-green algae). In the case of movement we distinguish between... 

Obviously the redox poise in biological systems is very important and the movement of selenium through this process has been investigated for denitrifiers such as Paracoccus denitrificans,159 a specialized selenate-respiring bacterium Thauera selenatis which used selenate as the sole electron acceptor,160,161 and phototrophic bacteria which produced different reduced forms of selenium when amended with either selenite or selenate and even added insoluble elemental Se.162 As noted above, Andreesen has commented on the importance of redox active selenocysteines135 and Jacob et al.136 note the importance of the thioredoxin system to redox poise. 

Methylated organo-selenium has been determined by GC/MS or fluorine-induced chemiluminescence to determine DMSe, DMDSe, and DMSeS. This last compound, dimethyl selenenyl sulfide, was mistakenly identified as dimethyl selenone (CH3Se02CH3) in earlier work with bacteria.181,182 However, much recent work with many microorganisms have shown ample evidence of DMSeS production from Gram-negative bacteria,181,183 phototrophic bacteria,167,184 phytoplankton185 and in B. juncea detailed above. SPME with microwave-induce plasma atomic emission spectrometry was recently used to... 

J. F. Imhoff (2001) True marine and halophilic anoxygenic phototrophic bacteria. Arch. Microbiol., 176 243-254... 

The immediate application of phototrophic bacteria in biotechnological systems of H2 generation is not possible due to many scientific and technological problems. Some of them... 

Criss RE (1999) Principles of stable isotope distribution. Oxford Univ Press, New York Croal LR, Johnson CM, Beard BL, Newman DK (2004) Iron isotope fractionation by anoxygenic Fe(II)-phototrophic bacteria. Geochim Cosmochim Acta in press Duce RA, Tindale NW (1991) Atmospheric transport of iron and its deposition in the ocean. Limnol... 

Figure 16. Conceptual model for biological redox cycling in a hot spring environment. Influx of external aqueous Fe(II) [Aeap-Ext] may reflect hydrothermal fluids or other sources of Fe(II),q. Oxidation of Fe(II),qis envisioned to occur by Fe(II)-oxidizing phototrophs in anaerobic conditions, but could also occur through interaction of Fe(II), with an oxygen-rich atmosphere. Oxidation of Fe(II) produces a flux of ferric oxide/hydroxide precipitates [Aeanjppt] that settle to the lower, anaerobic sections of the pool. These ferric precipitates are in turn partially reduced by DIR bacteria, returning a flux of Fe(II), to the pool [Aem-Bio] ...

Ehrenreich A, Widdel F (1994) Anaerobic oxidation of ferrous iron by purple bacteria, a new type of phototrophic metabolism. App Environ Microbio 60 4517-4526 Ehrlich HL (1996) Geomicrobiology. 3rd Edn. Marcel Dekker, New York, NY... 

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