Thauera linaloolentis sp. nov. and Thauera terpenica sp. nov., isolated on oxygen-containing monoterpenes (linalool, menthol, and eucalyptol) nitrate.

The monoterpenes menthol, linalool, and eucalyptol were recently used as sole electron donor and carbon source for the isolation of three denitrifying bacterial strains 21Mol, 47Lol, and 58Eu. The motile, mesophilic, Gram-negative rods had a strictly respiratory metabolism. Monoterpenes were completely mineralised to carbon dioxide, nitrate was reduced to dinitrogen. Strain 47Lol utilised aliphatic monoterpenes, strain 21Mol oxygenated monocyclic monoterpenes, and strain 58Eu the bicyclic eucalyptol and monocyclic monoterpene alkenes. The fatty acid composition of the strains indicated an allocation to the rRNA group III of pseudomonads. Comparative 16S rRNA gene sequence analyses revealed that the new isolates can be assigned as members of the genus Thauera within the beta subclass of Proteobacteria. DNA-DNA hybridisation studies indicated a relateness of 68.5% between strains 21Mol and 58Eu which shared 36.0% and 40.6% DNA similarity with strain 47Lol. The strains are described as new species belonging to the genus Thauera, strain 47Lol (DSM 12138T) as T. linaloolentis sp. nov. and strains 21Mol and 58Eu as T. terpenica sp. nov. with strain 58Eu (DSM 12139T) as type strain.