''Alicyclobacillus fastidiosus'' is a species of

Gram positive In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall. Gram-positive bact ...

, strictly aerobic,

bacterium Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were a ...

. The bacteria are acidophilic and produce endospores. It was first isolated from apple juice. The species was first described in 2007, and the name refers to the fastidious nature of the organism; the bacteria would start to die off after 7 days when plated on typical agar for isolating ''Alicyclobacillus''. Additionally, the species produced fewer spores than other members of its genus, and took much longer to produce the spores (i.e. several days versus 10 days). The optimum growth temperature for ''A. fastidiosus'' is 40–45 °C, and can grow in the 20–55 °C range. The optimum pH is 4.0–4.5, and cannot grow at pH 2.0 or pH 5.5. ''A. fastidiosus'' was found during a Japanese survey of various beverages and environments, which also discovered 5 other species of ''Alicyclobacillus'': '' A. contaminans'', '' A. kakegawensis'', '' A. macrosporangiidus'', '' A. sacchari'', and '' A. shizuokensis''.

References

Gram-positive bacteria Bacteria described in 2007 Bacillales {{bacilli-stub