alicyclobacillus contaminans alicyclobacillus contaminans alicyclobacillus contaminans is a species of gram positive, strictly aerobic, bacterium. the bacteria are acidophilic and produce endospores. it was first isolated during a survey from both orange juice, and soil in fuji city, japan. the species was first described in 2007, and the name is derived from the latin contaminans (contaminating). alicyclobacillus contaminans scientific classification domain: bacteria phylum: bacillota class: bacilli order: bacillales family: alicyclobacillaceae genus: alicyclobacillus species: a. contaminans binomial name alicyclobacillus contaminansgoto et al. 2007 the optimum growth temperature for a. contaminans is 50-55 °c, and can grow in the 35-60 °c range. the optimum ph is 4.0-4.5, and cannot grow at ph 3.0 or ph 6.0. a. contaminans was found during a japanese survey of various beverages and environments, which also discovered 5 other species of alicyclobacillus: a. fastidiosus, a. kakegawensis, a. macrosporangiidus, a. sacchari, and a. shizuokensis.