Lithotrophes

It is important to underscore the fact that carbon dioxide is required not only for the growth of strictly phototrophic and lithotrophic organisms. Many heterotrophic organisms that are heterotrophic have an obligate requirement for carbon dioxide for their growth. Illustrative examples include the following ... 

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

Kelly DP (1971) Autotrophy concepts of lithotrophic bacteria and their organic metabolism. Anna Rev Microbiol 25 177-210. 

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. 

Lithotroph An organism that derives its energy for growth from the conversion of inorganic substances. 

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) ... 

Paracoccus Capable of both lithotrophic and heterotrophic growth... 

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. 

As will be discussed below, respiration requires electron acceptors, and many of the lithotrophic modes of metabolism require oxygen, making many believe that they were rather late metabolic inventions, occurring only after the world was oxic, or at least after oxygen respiration was invented. This is not necessarily the case, for a variety of reasons first, the invention of oxygenic photosynthesis, and the resulting... 

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