Present address: Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA.
A likely role for anoxygenic photosynthetic microbes in the formation of ancient stromatolites
Article first published online: 6 APR 2007
Volume 5, Issue 2, pages 119–126, June 2007
How to Cite
BOSAK, T., GREENE, S. E. and NEWMAN, D. K. (2007), A likely role for anoxygenic photosynthetic microbes in the formation of ancient stromatolites. Geobiology, 5: 119–126. doi: 10.1111/j.1472-4669.2007.00104.x
- Issue published online: 6 APR 2007
- Article first published online: 6 APR 2007
- Received 25 August 2006; accepted 10 January 2007
Although cyanobacteria are the dominant primary producers in modern stromatolites and other microbialites, the oldest stromatolites pre-date geochemical evidence for oxygenic photosynthesis and cyanobacteria in the rock record. As a step towards the development of laboratory models of stromatolite growth, we tested the potential of a metabolically ancient anoxygenic photosynthetic bacterium to build stromatolites. This organism, Rhodopseudomonas palustris, stimulates the precipitation of calcite in solutions already highly saturated with respect to calcium carbonate, and greatly facilitates the incorporation of carbonate grains into proto-lamina (i.e. crusts). The appreciable stimulation of the growth of proto-lamina by a nonfilamentous anoxygenic microbe suggests that similar microbes may have played a greater role in the formation of Archean stromatolites than previously assumed.