Page:Bergey's manual of determinative bacteriology.djvu/96

 (Oxydobacteriaceae Orla-Jensen, pro parte, Cent. f. Bakt., II Abt., 22, 1909, 329; Protobacterieae Rahn, Cent. f. Bakt., II Abt., 96, 1937, 273.)

Me.tha.no.mo.na.da′ce.ae. M.L. noun Methanomonas, -adis a genus of bacteria; -aceae ending to denote a family; M.L. fern. pl. n. Methanomonadaceae the Methanomonas family.

Rod-shaped organisms deriving their life energy from the oxidation of simple compounds of hydrogen or carbon. Polar flagellate when motile. Gram-negative. Found in soil and water.

It is clear that the species placed in the genera in this family belong with other polar flagellate bacteria (the group of pseudomonads in the broad sense). Their method of deriving energy from oxidative processes is in accord with that of many other polar-flagellate bacteria. As a matter of convenience and as a means of emphasizing the fact that the species included here secure their energy from the oxidation of simple hydrogen and carbon compounds, the genera that have been proposed to include these species are grouped into a family separate from those of the species that secure their energy from the oxidation of simple nitrogen or sulfur compounds on the one hand, and those that normally secure their energy from the oxidation of glucose or other organic compounds on the other hand. Further studies of the differences in physiology found among the polar flagellate bacteria are badly needed.

I. Organisms deriving their life energy from the oxidation of simple compounds of hydrogen.


 * A. Cells capable of securing growth energy by the oxidation of methane.


 * B. Cells capable of securing growth energy by the oxidation of hydrogen.

II. Organisms deriving their life energy from the oxidation of carbon monoxide.

Me.tha.no.mo′nas. Gr. methy wine; Gr. methe strong drink; M.L. methanum methane; Gr. monas a unit, monad; M.L. fem. n. Methanomonas methane monad.

Cells monotrichous, capable of obtaining energy from oxidation of methane to CO2 and water.

The type species is Methanomonas methanica (Söhngen) Orla-Jensen.

1. Methanomonas methanica (Söhngen, 1906) Orla-Jensen, 1909. (Bacillus methanicus Söhngen, Cent. f. Bakt., II Abt., 15, 1906, 513; Orla-Jensen, Cent. f. Bakt., II Abt., 22, 1909, 311.)

me.tha′ni.ca. M.L. noun methanum methane; M.L. adj. methanicus relating to methane.

Short rods, 0.5 to 0.8 by 2.0 to 3.0 microns, motile in young cultures by means of a single flagellum. In older cultures nearly spherical. Can be cultivated in an atmosphere composed of one part CH4 and two parts air on washed agar containing the necessary inorganic salts. The growth is membranous. At the end of two weeks, the organisms changed an atmosphere containing 225 ml