Thioalkalivibrio sp. K90 mix

Thioalkalivibrio sp. K90mix growing at 3.6M of potassium. Photo credit: Dimitri Yu Sorokin

Thioalkalivibrio sp. K90mix is an extremely salt tolerant chemolithoautotrophic sulfur-oxidizing bacterium isolated from a mixture of soda lake sediments. It has a pH optimum of 10 and can grow at salinities up to 4.3M of sodium and 3.6M of potassium. The bacterium belongs to the gamma subdivision of the Proteobacteria and is most closely affiliated to Thioalkalivibrio nitratis. Its genome size is 3.4 Mb and %GC is 65.

Members of the genus Thioalkalivibrio are haloalkaliphilic chemolithoautotrophic bacteria using CO2 as a carbon source and reduced sulfur compounds as an energy source. They form a monophyletic group within the family Ectothiorhodospiraceae (Bacteria, Gammaproteobacteria). The group includes slow-growing species that are well adapted to life at high pH (pH 10) and high salinity (up to 4M of sodium) and have a versatile metabolism, including sulfur oxidation, denitrification and thiocyanate utilization. Thioalkalivibrio species can be used to remove noxious sulfur compounds from waste streams and energy carriers. In this respect they contribute to the following missions of the DOE, i.e., bioremediation and carbon sequestration. Comparative genomics will reveal the mechanism of adaptation to high pH and salinity, and provide insight into the uptake mechanism of inorganic carbon at high pH. In addition, comparative and functional genomics will show the ecological role and evolutionary history of these bacteria and might improve their sulfide-removing efficiency in bioreactors.


Sorokin, D. Yu., Lysenko, A.M., Mityushina, L. L., Tourova, T. P., Jones, B. E., Rainey, F. A., Robertson, L.A., and J. G. Kuenen. 2001. Thioalkalimicrobium aerophilum gen. nov., sp. nov. and Thioalkalimicrobium sibericum sp. nov., and Thioalkalivibrio versutus gen. nov., sp. nov., Thioalkalivibrio nitratis sp. nov., and Thioalkalivibrio denitrificans sp. nov., novel obligately chemolithoautotrophic sulfur-oxidizing bacteria from soda lakes.  JJSEM 51, 565-580.

Sorokin, D. Yu. and J. G. Kuenen. 2005. Haloalkaliphilic sulfur-oxidizing bacteria in soda lakes. FEMS Microbiol. Rev. 29, 685-702.