The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)
 
 
 
 
 

Experimental study of interactions between purple and green sulfur bacteria in sandy sediments exposed to illumination deprived of near-infrared wavelengths.

Sedimentary biofilms of the green sulfur bacterium Prosthecochloris aestuarii strain CE 2404, the purple sulfur bacterium Thiocapsa roseopersicina strain 5811, and a mixed culture of both were cultured in fine sand (100- to 300-microm grain size) within counter gradients of oxygen and sulfide. The artificial sediments were exposed to illumination deprived of near-infrared light (NIR) by filtering out the wavelengths longer than 700 nm to simulate the critical light conditions in submerged aquatic sediments. A 16 h of visible light-8 h of dark regimen was used. We studied the effects of these light conditions on the metabolisms of and interactions between both species by comparing the single species biofilms with the mixed biofilm. The photosynthesis rates of P. aestuarii were shown to be highly limited by the imposed light conditions, because the sulfide photooxidation rates were strongly stimulated when NIR was added. T. roseopersicina performed both aerobic chemosynthesis and photosynthesis, but the photosynthesis rates were low and poorly stimulated by the addition of NIR. This species decreased the penetration depth of oxygen in the sediment by about 1 mm by actively respiring oxygen. This way, the strict anaerobe P. aestuarii was able to grow closer to the surface in the mixed culture. As a result, P. aestuarii benefited from the presence of T. roseopersicina in the mixed culture, which was reflected by an increase in the biomass. In contrast, the density of the latter species was almost completely unaffected by the interaction. Both species coexisted in a layer of the same depth in the mixed culture, and the ecological and evolutionary implications of coexistence are discussed.[1]

References

 
WikiGenes - Universities