Cultivation of a novel cold-adapted nitrite oxidizing betaproteobacterium from the Siberian Arctic

摘要: Permafrost-affected soils of the Siberian Arctic were investigated with regard to identification nitrite oxidizing bacteria active at low temperature. Analysis fatty acid profiles enrichment cultures grown 4°C, 10°C and 17°C revealed a pattern that was different from known oxidizers but similar Betaproteobacteria. Electron microscopy two showed prevalent cells conspicuous ultrastructure. Sequence analysis 16S rRNA genes allocated organisms so far uncultivated cluster Betaproteobacteria, Gallionella ferruginea as next related taxonomically described organism. The results demonstrate novel genus chemolithoautotrophic is present in polygonal tundra can be enriched temperatures up 17°C. Cloned sequences high sequence similarities previously reported mesophilic habitats like activated sludge therefore an involvement this taxon oxidation nonarctic suggested. presented culture will provide opportunity correlate nitrification nonidentified environmental clones moderate give insights into mechanisms cold adaptation. We propose provisional classification bacterium 'Candidatus Nitrotoga arctica'.