Photoautotrophic bacteria

Photoautotrophs CO2 Light H2O, H2S, S, other inorganic compounds Green plants, algae, cyanobacteria, photosynthetic bacteria... 

Johnson CM, Beard BL, Albarede E (2004b) Overview and general concepts. Rev Mineral Geochem 55 1-24 Kalinowski BE, Liermann LJ, Brantley SL, Barnes A, Pantano CG (2000) X-ray photoelectron evidence for bacteria-enhanced dissolution of hornblende. Geochim Cosmochim Acta 64 1331-1343 Kappler A, Newman DK (2004) formation of Iron(III)-minerals by Iron(II)-oxidizing photoautotrophic bacteria. Geochim Cosmochim Acta 68 1217-1226... 

The inefficiency of microbial heterotrophy does have a side benefit as it enhances nutrient remineralization rates. This serves to increase the availability of inorganic nitrogen and phosphorus for the photoautotrophs. The multiple roles of bacteria in the marine food web were shown in Figure 23.2, with the component of the food web controlled by the algal herbivores depicted on the left side and the microbial loop on the right. The viral shunt acts on both pathways. 

Croal LR, Johnson CM, Beard BE, Newman DK (2004) Iron isotope fractionation by Ee(ll)-oxidizing photoautotrophic bacteria. Geochim Cosmochim Acta 68 1227-1242 Crosby HA, Roden EE, Johnson CE, Beard BL (2007) The mechanisms of iron isotope fractionation produced during dissimilatory Fe(III) reduction by Shewanellaputrefaciens and Geobacter... 

Photoautotrophic bacteria 8 Photofootprinting 266 Photorespiration 707 Photosynthesis 506,517, 705 Photosynthetic bacteria 7 Photosynthetic phosphorylation 303, 517 Photosynthetic reaction centers 71 Phthaldialdehyde 120s Phycoerythrin 22 Phycomycetes 20... 

Photoautotroph Sunlight h2o co2 Cells of higher plants, blue-green algae, photosynthetic bacteria... 

Autotrophic microorganisms synthesize organic substances from carbon dioxide through a process known as carbon dioxide fixation. They are important in nature because carbon dioxide fixation works as a precursor for the organic substrates that form the basis of the food chain for other organisms. Autotrophic bacteria include those that obtain their energy from light (photoautotrophs) and those that obtain it from the oxidation of chemical bonds (chemoau-totrophs). 

Within this diverse group of organisms, three basic evolutionary lineages are discernable (Delwiche, 2000). The first contains all prokaryotic oxygenic phytoplankton, which belong to one class of bacteria, namely, the cyanobacteria. Cyanobacteria are the only known oxygenic photoautotrophs that existed prior to —2.5 Gyr BP (Ga) (Lipps, 1993 Summons et al., 1999). These prokaryotes numerically dominate the photoautotrophic community in contemporary marine ecosystems and their continued success bespeaks an extraordinary adaptive capacity. At any moment in time, there are —10 cyanobacterial cells in the contemporary oceans. To put that into perspective, the number of cyanobacterial cells in the oceans is two orders of magnitude more than all the stars in the sky. 

A-9 Photoautotrophs - Photoautotrophs use light as an energy source and carbon dioxide as their main carbon source. They include photosynthetic bacteria (green sulfur bacteria, purple sulfur bacteria, and cyanobacteria), algae, and green plants. 

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