SULFOBACILLUS DISULFIDOOXIDANS SP-NOV, A NEW ACIDOPHILIC, DISULFIDE-OXIDIZING, GRAM-POSITIVE, SPORE-FORMING BACTERIUM

An acidophilic, disulfide-oxidizing, mesophilic, aerobic bacterium was isolated from wastewater sludge, The new organism is a gram-positive sporulated rod. It can use elemental sulfur and pyrite as sole energy sources and grows on organic substrates such as glutamate and glucose. It also grows on the following organic sulfur substrates: oxidized an d reduced glutathione, cysteine, cystine, and dithio(bis)benzothiazole and clearly shows a preference for disulfide bond-containing substrat es, The optimal pH of growth is between 1.5 and 2.5, depending on the substrate used, and the growth temperature range varies from 4 to 40 d egrees C, with an optimal value at 35 degrees C, The G+C chromosomal D NA content was measured at 53 +/- 1 mol%. Phylogenetic analysis of 16S genes coding for rRNA sequences places the new isolate in the genus S ulfobacillus. In addition, unique phenotypic and physiologic character istics and DNA homology values assign the isolate to a new species in the genus, Therefore, this new isolate has been named Sulfobacillus di sulfidooxidans and has been assigned ATCC number 51911.