Bacillus thermoamylovorans sp. nov., a moderately thermophilic and amylolytic bacterium

Abstract

A moderately thermophilic, facultatively anaerobic, amylolytic bacterium was isolated from palm wine, a tropical alcoholic beverage that was sampled in Senegal. The cells were gram positive, catalase positive, non-spore forming, rod shaped, and slightly motile with peritrichous flagella. The strain which we examined did not possess cytochrome and produced L-(+)-lactate, acetate, ethanol, and formate but not hydrogen during carbohydrate fermentation. Growth occurred at pH values ranging from 5.4 to 8.5, and optimum growth occurred at around pH 7.0. The optimum temperature for growth was around 50 degrees C, and the upper temperature limit for growth was 58 degrees C. The guanine-plus-cytosine content of the DNA was 38.8 +/- 0.2 mol%. A sequence analysis of the 16S rRNA gene revealed that the new organism is closely related phylogenetically to members of genus Bacillus. Despite the lack of spores, we propose that on the basis of phylogenetic characteristics, the new isolate should be classified as a new Bacillus species, Bacillus thermoamylovorans. The type strain is strain DKP (= Collection of Institut Pasteur CNCM I-1378).