Reduction of Metals and Nonessential Elements by Anaerobes
We are at the discovery stage for determining the ability of various bacteria to reduce metals and nonessential compounds. Mechanisms for these reductions generally have not yet been established, and it is apparent that much is unknown. A number of questions pertaining to reduction are raised: Which elements and compounds are reduced at the cell surface? Why are some of the compounds not reduced at the cell surface but become reduced at the plasma membrane or in the cytoplasm? What is the nature of the nonenergetic reactions in the cytoplasm of the bacterial cell? What are the physiologic substrates for the cytochromes and which reactions occur because of substitution of chemicals due to similar structural features? Certainly, considerable flexibility and adaptability of electron flow is expected in bacteria, and many new strains are expected to be found that obtain energy from these chemical reductions. The natural gene flow over the years in the anaerobic ecosystems has produced microorganisms of conside rable physiologic diversity. These anaerobic organisms continue to provide numerous biochemical challenges in the areas of anaerobic reduction of metals, metalloids, and nonessential elements by microorganisms.
Unable to display preview. Download preview PDF.
- Brookins DG. 1997. Eh-pH diagrams for geochemistry. Berlin: Springer-VerlagGoogle Scholar
- Caccavo F, Coates JD, Rossello-Mora RA, et al. 1996. Geobacter ferrireducens, a physiologically distinct dissimilatory Fe(III)-reducing bacterium. Arch Microbiol 165:3752–9.Google Scholar
- DeMoll-Decker H, Macy JM. 1993. The periplasmic nitrite reductase of Thauera selenatis may catalyze the reduction of selenite to elemental selenium. Arch Microbiol 160:241–7.Google Scholar
- Fauque G, LeGall J, Barton LL. 1991. Sulfate-reducing and sulfur-reducing bacteria. In: Shivley JM, Barton LL, editors. Variations in autotrophic life. New York: Academic Press. p 271–338.Google Scholar
- Lovley DR. 2000. Fe(III) and Mn(IV) reduction. In: Lovley DR, editor. Environmental microbe-metal interactions. Washington, DC: ASM Press. p 3–30.Google Scholar
- Malmqvist A, Welander T. 1992. Anaerobic removal of chlorate form bleach effluents. Water Sci Technol 25:237–42.Google Scholar
- Peck HD Jr. 1993. Bioenergetic strategies of sulfate-reducing bacteria. In: Odom JM, Singleton R Jr, editors. The sulfate-reducing bacteria: contemporary perspectives. New York: Springer-Verlag. p 41–76.Google Scholar
- Stumm W, Morgan JJ. 1996. Aquatic chemistry. 3rd ed. New York: Wiley.Google Scholar
- Wolfolk CA, Whiteley HR. 1962. Reduction of inorganic compounds with molecular hydrogen by Micrococcus lactilyicus. I. Stoichiometry with compounds of arsenic, selenium, tellurium, transition and other elements. J Bacteriol 84:647–58.Google Scholar
- Yurkova NA, Lyalikova NN. 1991. New vanadate-reducing facultative chemolithotrophic bacteria. Microbiology 59:672–7.Google Scholar