FAMILY VII. SPIRILLACEAE 



243 



support growth under any of the above 

 conditions when added to the mineral me- 

 dium: butyrates, citrates, lactates, malates, 

 malonates, succinates, tartrates or glucose. 



Indole not produced. 



Hydrogen sulfide not produced. 



Nitrites not produced from nitrates. 



Aerobic. 



Source: Five strains were isolated from 

 Boston, Mass., and Berkeley, California, 

 soils by inoculation of soil into a medium 

 containing potassium oxalate and other 

 minerals in distilled water. All soil samples 

 tested showed the presence of this species. 

 Ayers, Rupp and Johnson (U. S. Dept. Agr. 

 Bull. No. 782, 1919, 38 pp.) and den Dooren 

 de Jong (Dissertation, Delft, 1926, Table 

 XVIII) tested over 125 strains of bacteria 

 without finding any that decomposed ox- 

 alate. Bassilik (Jahrb. wiss. Bot., 63, 1913, 

 255) found only three strains out of 90 tested 

 which decomposed oxalate, two slowly; 

 the third was the species described by him 

 (Vibrio extorquens). 



Habitat: Widely distributed in soil. 



24. Vibrio extorquens (Bassalik, 1913) 

 Bhat and Barker, 1948. (Bacilhis extorquens 

 Bassalik, Jahrb. f. wiss. Bot., 53, 1913, 255; 

 Bhat and Barker, Jour. Bact., 55, 1948, 367; 

 Pseudomonas extorquens Janota, Med. Dos- 

 wiadczalna i Mikrobiol., 2, 1950, 131; see 

 Biol. Abstracts, .25,1951, Abs. no. 34148.) 



ex.tor'quens. L. puTt.ad] . extorquens twist- 

 ing out. 



Slightly curved rods, 1.5 by 3.0 microns. 

 Motile by means of a single, polar flagel- 

 lum. Gram-negative. 



Gelatin media: Poor growth. Colonies 

 small (less than 1 mm in diameter in 7 days), 

 round, entire, butyrous. Surface colonies 

 dirty yellow to yellowish red, eventually 

 becoming a beautiful red color. No lique- 

 faction. 



Oxalate and similar mineral media: 

 Growth rapid and abundant. 



Peptone-agar colonies: Growth slower 

 than on gelatin. 



Liquid oxalate media. Grows rapidly as 

 a rose-colored film on the bottom and walls 

 of the flask, leaving the liquid clear. 



Potato: Slow growth with darkening of 

 potato. 



Litmus milk: Not coagulated. Reaction 

 becomes alkaline but growth is poor. 



Aerobic, facultative. 



Optimum temperature, between 25° and 

 30° C. Poor growth at 37° C. 



Optimum pH : Prefers media with an alka- 

 line reaction. 



Distinctive characters: In old cultures in 

 liquid calcium oxalate media and especially 

 in media made with plant materials con- 

 taining oxalate crystals, the cells become 

 encrusted with a surface deposit. This ap- 

 pears to be calcium carbonate and is easily 

 dissolved with dilute acid, especially dilute 

 HCl. 



Source: Originally isolated by adding the 

 e.xcreta of earthworms that had ingested 

 plant materials containing oxalate crystals 

 to a liquid medium containing ammonium 

 oxalate. Pure cultures were isolated with 

 difficulty by using a silica gel medium con- 

 taining ammonium oxalate. Later these 

 organisms were found to be generally pres- 

 ent in forest and garden soils in Switzerland. 



Habitat: Presumably widely distributed 

 in soil. 



25. Vibrio cuneatus Gray and Thornton, 

 1928. (Cent. f. Bakt., II Abt., 73, 1928, 92.) 



cu.ne.a'tus. L. part. adj. amea/z/s wedge- 

 shaped. 



Curved rods, 1.0 by 1.0 to 3.0 microns, 

 the cells tapering at one extremity. Motile 

 by means of one to five polar flagella. Gram- 

 negative. 



Gelatin colonies: Liquefied. 



Gelatin stab: Liquefied. 



Agar colonies: Circular to amoeboid, 

 white to buff, flat to convex, smooth, trans- 

 lucent, border entire. 



Agar slant: Filiform, whitish, smooth, 

 glistening. 



Indole production not recorded. 



No acid from carbohydrate media. 



Starch not hydrolyzed. 



Nitrites not produced from nitrates. 



Attacks naphthalene. 



Aerobic, facultative. 



Optimum temperature, between 30° and 

 35° C. 



Source: One strain was isolated from 

 soil from Rothamsted, England. 



Habitat: Soil. 



