sulfobacillus acidophilus sulfobacillus acidophilus sulfobacillus acidophilus is a species of moderately thermophilic mineral-sulphide-oxidizing bacteria. it is gram-positive, acidophilic and ferrous-iron-oxidising as well. sulfobacillus acidophilus scientific classification domain: bacteria phylum: bacillota class: incertae sedis genus: sulfobacillus species: s. acidophilus binomial name sulfobacillus acidophilusnorris et al. 1996