Page:Bergey's manual of determinative bacteriology.djvu/206

 Thesis, Leiden, 1898, 115 pp.. Delft, in Cent. f. Bakt., II Abt., 4, 1898, 857; Acetobacter Beijerinck, Proc. Kon. Akad. v. Wetenschapp., Amsterdam, 2, 1900, 503; Acetobacter Beijerinck. Arch, néerl. d. sciences exact. et natur., Sér. II, 6, 1901, 212; Acetobacter in Fuhrmann, Beiheft Bot. Centralbl., Orig., 19, 1905, 8; Acetimonas Orla-Jensen, Cent. f. Bakt., II Abt., 22, 1909, 312; Acetobacter Winslow et al.. Jour. Bact., 5, 1920, 201; Acetomonas Leifson, Antonie van Leeuwenhoek, 20, 1954, 109.)

A.ce.to.bac'ter. L. noun acetum vinegar; M.L. mas.n. bacter the masculine form of the Gr. neut.n. bactrum a rod or staff; M.L. mas.n. Acetobacter vinegar (acetic) rod.

Individual cells ellipsoidal to rod-shaped, occurring singly, in pairs or in short or long chains. Motile with polar flagella, or non-motile. Involution forms may be spherical, elongated, filamentous, club-shaped, swollen, curved or may even appear to be branched. Young cells Gram-negative; old cells often Gram- variable. Obligate aerobes; as a rule strongly catalase-positive, sometimes weakly so. Oxidize various organic compounds to organic acids and other oxidation products which may undergo further oxidation. Common oxidation products include acetic acid from ethyl alcohol, gluconic and 5-ketogluconic acid from glucose, dihydroxy-acetone from glycerol, sorbose from sorbitol, etc. Nutritional requirements vary from simple to complex. Development generally best in yeast infusion or yeast autolysate media with added ethyl alcohol or other o.xidizable substrates. Optimum temperature varies with the species. Widely distributed in nature where they are particularly abundant in plant materials undergoing alcoholic fermentation; of importance to man for their role in the completion of the carbon cycle and for the production of vinegar.

It is recognized that there are marked morphological and physiological similarities between species of Acetobacter and Pseudomonas (see Vaughn, Jour. Bact., 46, 1943, 394; and Stanier, Jour. Bact., 54, 1947, 191, among others). However, the species of Acetobacter may be differentiated from all other Pseudomonadaceae by their unique ability to oxidize significant quantities of ethanol under the extremely acidic conditions imposed by the presence of from about 2 to more than 11 per cent acetic acid.

The evidence also indicates a significant difference in the end-products of hexose and disaccharide oxidation. The species of Acetobacter produce gluconic and 5-ketogluconic acids from both glucose and maltose whereas species of Pseudomonas oxidize glucose to gluconic and 2-ketogluconic acids and maltose to maltobionic acid (see Pervozvanski, Khim. Referat. Zhur., 7, 1939, 43; Lockwood, Tabenkin and Ward, Jour. Bact., 42, 1941, 51; Stodola and Lockwood, Jour. Biol. Chem., 171, 1947, 213; Kluyver, Deley and Rijven, Antonie van Leeuwenhoek, 16, 1950, 1; and Foda and Vaughn, Jour. Bact., 65, 1953, 233, among others).

The type species is Acetobacter aceti (Beijerinck) Beijerinck.

I. Oxidize acetic acid to carbon dioxide and water.
 * A. Utilizes ammonium salts as a sole source of nitrogen (Hoyer's solution).