Anoxybacillus ayderensis sp. nov. and Anoxybacillus kestanbolensis sp. nov.

Two thermophilic bacilli were isolated from mud and water samples of the Ayder and Kestanbol hot springs in the provinces of Rize and Canakkale, respectively, in Turkey. Strains AB04T and K4T were sporulating, Gram-positive, rod-shaped bacteria. These isolates were moderately thermophilic (with an optimum temperature for growth of 50–55 °C), facultative anaerobes able to grow on a wide range of carbon sources including d-glucose, d-raffinose, d-sucrose, d-xylose, d-fructose, l-arabinose, maltose, d-mannose and d-mannitol. Analysis of the 16S rRNA gene sequences showed that these isolates resembled Anoxybacillus flavithermus DSM 2641T and Anoxybacillus gonensis NCIMB 13933T. DNA–DNA hybridization data revealed that thermophilic isolate AB04T has only 51·2 % relatedness to A. flavithermus, 45·1 % relatedness to Anoxybacillus pushchinoensis and 68·6 % relatedness to A. gonensis. Thermophilic isolate K4T showed only 60·4 % relatedness to A. flavithermus, 42·9 % relatedness to A. pushchinoensis and 38·5 % relatedness to A. gonensis. On the basis of the DNA–DNA hybridization data, isolates AB04T and K4T are not related to A. flavithermus DSM 2641T, A. pushchinoensis DSM 12423T or A. gonensis NCIMB 13933T at the species level, but show relatedness to one another of 40·5 %. On the basis of the data presented, it is proposed that strains AB04T (=NCIMB 13972T=NCCB 100050T) and K4T (=NCIMB 13971T=NCCB 100051T) be designated as the type strains of Anoxybacillus ayderensis sp. nov. and Anoxybacillus kestanbolensis sp. nov., respectively.