Alicyclobacillus pohliae sp. nov., a thermophilic, endospore-forming bacterium isolated from geothermal soil of the north-west slope of Mount Melbourne (Antarctica)

1 Dipartimento di Biologia Evolutiva, Università degli Studi di Siena, Via A. Moro 2, 53100 Siena, Italy 2 Dipartimento di Biotecnologie Agrarie, Sezione di Microbiologia, Università degli Studi di Firenze, Piazzale delle Cascine 24, 50144 Firenze, Italy Correspondence Laura Marri marri{at}unisi.it Gram-positive, rod-shaped, endospore-forming, thermophilic bacteria were isolated from a geothermal soil collected on the north-west slope of Mount Melbourne in Antarctica. They grew aerobically at 42–60 °C (optimum 55 °C) and at pH 4.5–7.5 (optimum pH 5.5). Phylogenetic analysis of 16S rRNA gene sequences showed that these isolates were related most closely to the type strain of Alicyclobacillus pomorum (91 % similarity). Growth occurred in the presence of ferrous iron at micromolar concentrations and acid was produced from various sugars. Iso-branched fatty acids C 15 : 0 (45.56 %) and C 17 : 0 (35.81 %) were the most abundant cellular fatty acids. The DNA G+C content was 55.1 mol%. On the basis of phenotypic and phylogenetic characteristics, it is concluded that these strains represent a novel species of the genus Alicyclobacillus , for which the name Alicyclobacillus pohliae sp. nov. is proposed. The type strain is MP4 T (=CIP 109385 T =NCIMB 14276 T ). The GenBank/EMBL/DDBJ accession numbers for the 16S rRNA gene sequences of strains MP1, MP2, MP3 and MP4 T are AJ607429 , AJ607430 , AJ607431 and AJ564766 , respectively.