Geobacillus jurassicus sp. nov., a new thermophilic bacterium isolated from a high-temperature petroleum reservoir, and the validation of the Geobacillus species

• Published in: Systematic and applied microbiology 2005-01, Vol.28 (1), p.43-53
• Main Authors: Nazina, Tamara N., Sokolova, Diana Sh, Grigoryan, Alexander A., Shestakova, Nataliya M., Mikhailova, Ekaterina M., Poltaraus, Andrei B., Tourova, Tatiyana P., Lysenko, Anatolii M., Osipov, George A., Belyaev, Sergey S.
• Format: Article
• Language: English
• Subjects: 16S rDNA Sequence; Aerobiosis; Bacillaceae - classification; Bacillaceae - cytology; Bacillaceae - isolation & purification; Bacillaceae - physiology; Bacteria; Bacterial Typing Techniques; Base Composition; Carbohydrate Metabolism; Carboxylic Acids - metabolism; China; DNA, Bacterial - chemistry; DNA, Bacterial - isolation & purification; DNA, Ribosomal - chemistry; DNA, Ribosomal - isolation & purification; DNA–DNA hybridization; Environmental Microbiology; Fatty acids; Fatty Acids - analysis; Fatty Acids - isolation & purification; Genes, rRNA; Gentian Violet; Geobacillus; Geobacillus jurassicus; Geobacillus jurassicus sp. nov; Hydrocarbons - metabolism; Molecular Sequence Data; Nucleic Acid Hybridization; Petroleum - metabolism; Petroleum - microbiology; Phenazines; Phylogeny; RNA, Bacterial - genetics; RNA, Ribosomal, 16S - genetics; Sequence Analysis, DNA; Spores, Bacterial - cytology; Taxonomy; Temperature; Thermophile
• ISSN: 0723-2020; 1618-0984
• DOI: 10.1016/j.syapm.2004.09.001

Four thermophilic, spore-forming bacterial strains, DS1 T, DS2, 46 and 49, were isolated from the high-temperature Dagang oilfield, located in China. The strains were identified by using the polyphasic taxonomy approach. These were aerobic, gram-positive, rod-shaped, moderately thermophilic (with an optimum growth temperature of 60–65 °C), chemoorganotrophic bacteria capable of growing on various sugars, carboxylic acids and crude oil. Two strains, DS1 T and DS2, were capable of growing on individual saturated hydrocarbons. The G+C content of the DNA of strains DS1 T and DS2 was 54.5 and 53.8 mol%, respectively. The phylogenetic analysis of the 16S rDNA of strains DS1 T and DS2 showed that they form a separate cluster within the genus Geobacillus. The cellular fatty acids of the isolates were dominated by iso-15:0, iso-16:0 and iso-17:0 acids, which are the typical fatty acids of bacteria from the genus Geobacillus. The DNA−DNA hybridization study and the comparative analysis of the morphological and chemotaxonomic characteristics of strains DS1 T and DS2 showed that they differ from the previously described Geobacillus species and belong to a new species, which was called Geobacillus jurassicus. DS1 T (=VKM B-2301 T,=DSM 15726 T) is the type strain of this species According to both DNA–DNA reassociation studies and 16S rDNA sequence analysis, two other strains, 46 and 49, were assigned to the species G. stearothermophilus. In this paper, we provide evidence that the new combinations G. stearothermophilus, G. thermoleovorans, G. kaustophilus, G. thermoglucosidasius and G. thermodenitrificans may be considered to be valid.