Alicyclobacillus aeris sp. nov., a novel ferrous- and sulfur-oxidizing bacterium isolated from a copper mine.

A novel mesophilic, acidophilic, endospore-forming bacterium, designated strain ZJ-6(T), was isolated from Zi-Jin copper mine in Inner Mongolia, China. Cells of strain ZJ-6(T) were rod-shaped, stained Gram-positive or were Gram-variable, and grew aerobically at 25-35 degrees C (optimum, 30 degrees C) and pH 2.0-6.0 (optimum, pH 3.5). 16S rRNA gene sequence analysis showed that strain ZJ-6(T) was related phylogenetically to members of the genus Alicyclobacillus, with 16S rRNA gene sequence similarities of 89.5-94.2 %. Cells contained MK-7 as the major quinone and the DNA G+C content was 51.2 mol%. Strain ZJ-6(T) possessed a number of phenotypic characteristics that differentiated it from recognized Alicyclobacillus species, including its growth temperature, assimilation of various carbon sources, production of acids from a range of compounds, and the ability to grow chemoautotrophically using ferrous iron, elemental sulfur and tetrathionate as electron donors. The predominant cellular fatty acids of strain ZJ-6(T) were anteiso-C(15 : 0) (67.1 %), iso-C(16 : 0) (7.7 %) and anteiso-C(17 : 0) (7.4 %); omega-alicyclic fatty acids were not found. On the basis of these results, it is concluded that strain ZJ-6(T) represents a novel species within the genus Alicyclobacillus, for which the name Alicyclobacillus aeris sp. nov. is proposed; the type strain is ZJ-6(T) (=CGMCC 1.7072(T)=NBRC 104953(T)).