Genus VI. Azotomonas Stapp, 1940.[1]
(Stapp, Zent. f. Bakt., II Abt., 102, 1940, 18; not Azotomonas Orla-Jensen, Cent. f. Bakt., II Abt., 24, 1909, 484.)
A.zo.to.mo'nas. Gr. azous without life; Fr. noun azote nitrogen; Gr. fem.n. monas unit, monad; M.L. fem.n. Azotomonas nitrogen (-fixing) monad.
Rod- to coccus-shaped cells. Motile by means of 1 to 3 polar flagella. No fat-like reserve food granules in the cells. Chemoheterotrophic. Produce acid and sometimes gas from glucose and other sugars and alcohols. Many carbon compounds other than sugars are used as sources of energy. Indole is produced. Aerobic. Active in the fixation of atmospheric nitrogen. Found in soil.
The type species is Azotomonas insolita Stapp.
Key to the species of genus Azotomonas.
I. Acid and gas from glucose.
1. Azotomonas insolita.
II. Acid but no gas from glucose.
2. Azotomonas fluorescens.
1. Azotomonas insolita Stapp, 1940. (Abstracts of Communications, Third Internat. Congr. for Microbiol., Sect. VIII, 1939, 306; abst. in Proc. Soil Sci. Soc. of America, 4, 1939, 244; Zent. f. Bakt., II Abt., 102, 1940, 1.)
in.so'li.ta. L. adj. insolitus unusual.
Coccoid rods 0.6 to 1.2 by 0.6 to 1.8 microns. Motile by means of 1 to 3 polar flagella. Gram-negative.
Gelatin: No liquefaction.
Agar colonies: Flat, whitish, entire, weakly fluorescent.
Agar slant: Glistening, white growth.
Broth: Strongly turbid; sediment; pellicle.
Milk: Unchanged.
Potato: Growth somewhat dry, not slimy, dirty gray, spreading.
Hydrogen sulfide is produced.
Acid and gas from adonitol, arabinose, dextrin, glucose, galactose, glycerol, inositol, lactose, fructose, maltose, mannose, mannitol, raffinose, rhamnose, salicin, sorbitol, starch, sucrose and xylose.
Starch is hydrolyzed.
Nitrites produced from nitrates.
Atmospheric nitrogen is fixed.
Ammonium salts are utilized.
Aerobic.
Temperature relations: Optimum, between 25° and 30° C. Minimum, between 7.0° and 9.5° C. Maximum, 48° C. Good growth at 37° C. Thermal death point, 60° C.
Limits of pH, 3.3 to 9.5.
Source: Isolated from a mixture of chopped cotton husks and rice hulls.
Habitat: Soil.
2. Azotomonas fluorescens Krassilnikov, 1947. (Quoted from Krassilnikov, Guide to the Bacteria and Actinomycetes, Izd. Akad. Nauk, U.S.S.R., Moskau, 1949, 420.)
flu.o.res'cens. L. noun fluor a flux; M.L. v. fluoresco to fluoresce; fluor-spar, a fluxing mineral which is fluorescent; M.L. part. adj. fluorescens fluorescing.
Translated by Dr. A. Petraitis, New York State Experiment Station, Geneva, New York.
Rod-shaped cells, 0.5 to 0.8 by 2.0 to 5.0 microns, which become shorter in old cultures. Motile by means of one to three polar flagella. Gram-negative.
Gelatin: Slow liquefaction.
Inorganic media with or without nitrogen: Good growth.
Colonies are wide, smooth and glistening.
A slightly yellowish or violet fluorescent pigment is produced which diffuses through the medium.
Milk: Peptonized.
- ↑ Rearranged by Dr. A. W. Hofer, New York State Experiment Station, Cornell University, Geneva, New York, November, 1953.
