Extremophiles

, Volume 5, Issue 1, pp 45–51

Isolation and characterization of a mixotrophic sulfur-oxidizing Thermus scotoductus

  • Sigurlaug Skirnisdottir
  • Gudmundur O. Hreggvidsson
  • Olle Holst
  • Jakob K. Kristjansson
Original paper

DOI: 10.1007/s007920000172

Cite this article as:
Skirnisdottir, S., Hreggvidsson, G., Holst, O. et al. Extremophiles (2001) 5: 45. doi:10.1007/s007920000172

Abstract

Thermophilic, faculatatively mixotrophic sulfur-oxidizing bacteria were isolated from a sulfide-rich, neutral hot spring in Iceland. The strain, IT-7254, used thiosulfate and elemental sulfur as electron donors, oxygen and nitrate as electron acceptors, and acetate and other organic compounds as carbon sources. After a few days of growth in the presence of thiosulfate, this strain formed sulfur globules. Comparison of intracellular enzymes and heme proteins of heterotrophically and mixotrophically grown cells showed some differences. The new isolate belonged to Thermus scotoductus because the small subunit (SSU) rRNA gene sequence analysis showed 98.6% sequence similarity and 84% DNA:DNA reassociation to Thermus scotoductus NMX2 A.1. It is also close to Thermus antranikianii HN3-7, with 98.3% and 79% SSU rRNA sequence similarity and DNA:DNA reassociation, respectively. It was also found that both Thermus NMX2 A.1 and T. antranikianii HN3-7 were able to oxidize thiosulfate but that the T. scotoductus type strain SE-1 was not. This is the first report of Thermus strains that are capable of mixotrophic growth with sulfur oxidation.

Mixotrophic Sulfur-oxidizing bacteria Thermus Hot spring 

Copyright information

© Springer-Verlag 2001

Authors and Affiliations

  • Sigurlaug Skirnisdottir
    • 1
  • Gudmundur O. Hreggvidsson
    • 1
  • Olle Holst
    • 3
  • Jakob K. Kristjansson
    • 1
  1. 1.Prokaria Ltd., Gylfaflot 5, IS-112 ReykjavikIceland
  2. 2.Institute of Biology, University of Iceland, ReykjavikIceland
  3. 3.Department of Biotechnology, Center for Chemistry and Chemical Engineering, Lund University, LundSweden