Lithotrophic oxidation

Lithotrophic oxidation of ammonium and methane by obligate aerobic organisms ... 

Anaerobic lithotrophs that oxidize ammonium using nitrite as electron acceptor (anammox) are noted later in the section on anaerobic bacteria. 

A facultative autotroph (lithotroph) strain MLHE-1 was able to oxidize arsenite under anaerobic conditions to arsenate using nitrate as electron acceptor (Oremland et al. 2002). 

Koops, H.P. and Chritian, U., The lithotrophic ammonia-oxidizing bacteria, in Variations in Autotrophic Life, Shively, J.M. and Burton, L.L., Eds., Harcourt Brace Jovanovich Pub., New York, 1991. 

This enzyme is commonly found in aerobic sulfur-oxidizing lithotrophs, but its importance as an alternative to a hydration-dehydrogenation electron-transport-linked energy-generating mechanism is still disputed (Kelly 1999) ... 

Jenni, B., Realini, L., Aragno, M. Tamer, A. U. (1988). Taxonomy of non H2-lithotrophic, oxalate-oxidizing bacteria related to Alcaligenes eutrophus. Systematic and Applied Microbiology, 10, 126-30. 

Wodara, C., Bardischewsky, F., and Friedrich, C. G., 1997, Cloning and characterization of sulfite dehydrogenase, two c-type cytochromes, and a flavoprotein of Paracoccus denitri-ficans GB17 essential role of sulfite dehydrogenase in lithotrophic sulfur oxidation. J. Bacterial. 179 501495023. 

Oxidation Lithotrophic iron oxidation Cell membrane Anoxic or oxic... 

Neubauer S. C., Emerson D., and Megonigal J. P. (2002) Life at the energetic edge kinetics of circumneutral iron oxidation by lithotrophic iron-oxidizing bacteria isolated from the wetland-plant rhizophere. Appl. Environ. Microbiol. 68, 3988-3995. 

Hydrogen Oxidation Kinetics. Shea et al. (22) studied the kinetics of methane fermentation by an enrichment culture of lithotrophic (autotrophic) hydrogen oxidizing methanogenic bacteria at 37 °C. Reported values of the kinetic coeflScients are as follows (1) Y = 0.043 mg volatile suspended solids per mg of hydrogen COD removed, (2) b = —0.009 day"S (3) k = 24.8 mg hydrogen COD removed per mg volatile suspended solids per day and (4) Ks = 569 mm of mercury, hydrogen pressure. 

Although the association of lithotrophic bacteria and sulfur oxidation is... 

The presence of iron oxyhydroxide coatings (i.e., Fe plaque, often dominated by ferrihydrite) on the surface of wetland plant roots is visual evidence that subsurface iron oxidation is occurring in otherwise anoxic wetland soils and sediments. Oxygen delivered via radial O2 loss may react with reduced iron in soil pore spaces to form oxidized iron that can be deposited on the plant roots as Fe plaque. Despite a long history of observing Fe plaque on wetland plant roots and understanding the basics of plaque formation [i.e., reaction of plant-transported O2 with Fe(II) in soils and sediments], it was largely assumed that plaque formation is predominately an abiotic (i.e., chemical) process because the kinetics of chemical oxidation can be extremely rapid (Mendelssohn et al., 1995). However, recent evidence has demonstrated that populations of lithotrophic FeOB are associated with Fe plaque and may play a role in plaque deposition. 

Although most of the sulfate-reducing bacteria are heterotrophic, some lithotrophic sulfate-reducing bacteria are known these bacteria grow by oxidizing hydrogen gas (H2) with sulfate (S042 ) (Fig. 1.11). 

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