Iron/manganese oxidizing bacteria

Iron/manganese-oxidizing bacteria. Bacteria that derive energy from the oxidation of Fe + to Fe + are commonly reported in deposits associated with MIC. They are almost always observed in tubercles (discrete hemispherical moimds) over pits on steel surfaces. The most common iron oxidizers are foimd in the environment in long protein sheaths or filaments. While the cells themselves are rather indistinctive in appearance, these long filaments are readily seen imder the microscope and are not likely to be confiised with other life forms. The observation... 

Metal cycles Iron and manganese oxidation and reduction Iron bacteria and manganese bacteria... 

Manganese and iron oxidation are coupled to cell growth and metabolism of organic carbon. Microbially deposited manganese oxide on stainless and mild steel alters electrochemical properties related to the potential for corrosion. Iron-oxidizing bacteria produce tubercles of iron oxides and hydroxides, creating oxygen-concentration cells that initiate a series of events that individually or collectively are very corrosive. 

The importance of bacteria in mediating Mn(II) oxidation in certain environments is evident. But, the mechanisms whereby bacteria oxidize Mn(II) are poorly understood. Some bacteria synthesize proteins or other materials that enhance the rate of Mn(II) oxidation (.52). Other strains of bacteria require oxidized manganese to oxidize Mn(II) (53), suggesting that they may catalyse the oxidation of Mn(II) on the manganese oxide surface. Other bacteria may catalyse the oxidation of Mn(II) on iron oxide surfaces, as iron is associated with manganese deposits on bacteria collected in the eastern subtropical North Pacific (54). 

Aerobic, chemolithotrophic bacteria. Colorless sulfur bacteria Thiobacillus iron or manganese-oxidizing bacteria, magnetotactic bacteria nitrifying bacteria Nitrobacter, Nitrosomonas... 

Manganese (oxy)(hydr)oxide sorbents and manganese-oxidizing bacteria Permeable reactive barriers with lime, iron oxides, and limestone Siderite (coprecipitation and possibly sorption)... 

Muir, M. D. Microenvironments of some modern and fossil iron- and manganese-oxidizing bacteria, in Environmental biogeochemistry and geomicrobiology 3 (ed. Krumbein, W. E.) p. 937, Ann Arbor Mich Ann Arbor Publishers Sci. 1978... 

Ehrlich, H. L., Ingle, J. L. Salerno, J. C. (1991). Iron and manganese oxidizing bacteria. In Variations in Autotrophic Life, ed. J. M. Shively L. L. Barton. London Academic Press, pp. 147-70. 

Manganese-oxidizing bacteria could also be identified . As manganese in the sediments has to be reduced to Mn ions to become soluble and thus to get mobilized, the very important question arises how or where it is reoxidized. Generally, the bottom-near sea-water of Central Pacific is so rich in dissolved oxygen that manganese and iron will be oxidized when coming into the contact with sea-water (at the sediment-water interface and in the mobile, nearly liquid uppermost sediment layer). 

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