Page:Bergey's manual of determinative bacteriology.djvu/221

 Acid but no gas from various sugars and alcohols. Starch is hj'drolyzed. Fixes nitrogen. Nitrites not produced from nitrates. Aerobic. Source: Isolated from soil. Habitat: Soil.

Zy.mo'mo.nas or Zy.mo.mo'nas. Gr. noun zyme leaven, ferment; Gr. noun monas a unit, monad; M.L. fem.n. Zymomonas fermenting monad.

Rod-shaped cells, occasionally ellipsoidal. Motile cells are lophotrichous. Anaerobically ferment glucose with the production of carbon dioxide, ethyl alcohol and some lactic acid. Found in fermenting beverages such as pulque, palm juice and beer.

The type species is Zymomonas mobilis (Lindner) Kluyver and van Niel.

1. Zymomonas mobilis (Lindner, 1928) Kluyver and van Niel, 1936. (Termobac- terium mobile Lindner, Atlas d. Mikrosk Grundl. d. Garungsk., 3 Aufl., 2, 1928, Taf 68; also see Lindner, 50 Jubilaumsber Westpreuss. Bot.-Zool. Vereins, 1928, 253 Pseudomonas lindneri Kluyver and Hoppen brouwers, Arch. f. Mikrobiol., £, 1931, 259 Zymomonas mobile (sic), Kluyver and van Niel, Zent. f. Bakt., II Abt., 94, 1936, 399 Saccharomonas lindneri Shimwell, Jour. Inst. Brewing, 56 (N. S. 47), 1950, 179.) mo'bi.lis. L. adj. mobilis movable, motile. Short rods with rounded ends, 1.4 to 2.0 by 4.0 to 5.0 microns. Occur usually as pairs with a central constriction and rarely as short chains. Motile with polar flagella. Gram-negative. Peptone gelatin: Poor growth. Peptone agar: Poor growth. Wort agar: White, round, raised colonies 1 mm in diameter. Good growth. Still better growth where 2 per cent sucrose or yeast extract with sucrose is added. Chalk may be added to neutralize acid. Wort gelatin stab: Uniform growth in stab; no surface growth. No liquefaction. Broth: Poor growth in peptone or yeast extract broth unless sugars are added. Carbon dioxide, ethyl alcohol and some lactic acid produced from glucose and fructose but not from mannose. Ferments sucrose usually after a somewhat prolonged lag period. May produce as much as 10 per cent alcohol. Catalase-positive. Anaerobic, although with a certain oxygen tolerance of aerobic growth in the presence of fermentable sugars. Optimum temperature, 30° C. Distinctive character: Apart from the production of some lactic acid, the fermen- tation resembles the alcoholic fermentation produced by j'easts. Source : Isolated from the fermenting sap (pulque) of Agave americana in Mexico and from fermenting palm juice {Arenga sac- charifera) in Sumatra and Java (Roelofsen, Natuurwetenschappelijk Tijdschrift voor Ned-. Indie, 101, 1941, 374). Habitat: Found in fermenting plant juices in tropical countries (Mexico and Indonesia).

2. Zymomonas anaerobia (Shimwell, 1937) Kluyver, comb. nov. (Achromobacier anaerobium Shimwell, Jour. Inst. Brewing, 43, 1937, 507; Saccharomonas anaerobia Shim- well, op. cit., 56 (N. S. 47), 1950, 179 (type species of genus Saccharomonas Shimwell).) an.a.e.ro'bi.a. Gr. pref. an not; Gr. noun aer air; Gr. noun bins life; M.L. adj. anaerobius not living in air. Rods, 1.0 to 1.5 by 2.0 to 3.0 microns, plump with rounded ends. Cells occasionally clump together to form rosette-like clusters. Young cells actively motile with lophotri- chous flagella, old cells become non-motile. Not encapsulated. Gram-negative. Glucose-beer-gelatin stab: Dense, fili- form to beaded growth in stab; no surface growth. No liquefaction.