FAMILY ACHROMOBACTERIACEAE 



413 



Key to the species of genus Alcaligenes. 

 I. Gelatin not liquefied. 



A. Motile. 



1. Does not produce ropiness in milk. Found in the intestinal tract. 



1. Alcaligenes faecalis. 



2. Produces ropiness in milk. 



2. Alcaligenes viscosus. 



B. Non-motile. 



1. Found in the intestinal tract. 



3. Alcaligenes metalcaligenes . 



II. Gelatin liquefied. 



A. Motile. 



1. Milk peptonized; blood serum liquefied. 



4. Alcaligenes bookeri. 



2. Milk not peptonized; blood serum not liquefied. 



.5. Alcaligenes recti. 



B. Non-motile. 



1. Milk peptonized, slimy. 



6. Alcaligenes marshallii. 



1. Alcaligenes faecalis Castellani and 

 Chalmers. (Bacillus faecalis alcalig- 

 enes Petruschky, Cent. f. Bakt., I Abt., 

 19, 1896, 187; Bacterium fecalis alcalig- 

 enes Chester, Ann. Rept. Del. Col. Agr. 

 Exp. Sta., 9, 1897, 73; Bacterium alcalig- 

 enes Lehmann and Neumann, Bakt. 

 Diag., 2 Aufl., 1899, 242; Bacillus alcalig- 

 enes Migula, Syst. d. Bakt., 2, 1900, 737; 

 Castellani and Chalmers, Manual Trop. 

 Med., 1919, 936; Bacillus fecalis -alcalig- 

 enes Holland, Jour. Bact., 5, 1920, 218; 

 Bacterium fecalis -alcaligenes Holland, 

 ibid.; Vibrio alcaligenes Lehmann and 

 Neumann, Bakt. Diag., 7 Aufl., ,?, 1927, 

 548: Bacterium faecale alcaligenes Mo- 

 nias. Jour. Inf. Dis., 43, 1928, 330.) From 

 Latin /aex, dregs; M. L., fecal. 



Rods : 0.5 by 1.0 to 2.0 microns, occur- 

 ring singly and in pairs, and occasionally 

 in long chains. Motile with peritrichous 

 flagella. In some strains, the majority of 

 the individual cells show only a single 

 flagellum. This is apt to be in a lateral 

 rather than in the polar position. Gram- 

 negative . 



Gelatin colonies: Circular, grayish, 

 translucent. 



Gelatin stab: Gray surface growth. 

 No liquefaction. 



Agar colonies : Transparent with opaque 

 center, undulate margin. 



Agar slant: White, glistening, opales- 

 cent, undulate margin. 



Broth: Turbid, with thin pellicle, and 

 viscid sediment. Gives oft' ammonia. 



Litmus milk: Alkaline. 



Potato: Scanty to abundant, yellowish 

 to brownish growth. 



Indole not formed. 



Nitrite production from nitrates vari- 

 able. 



No acid or gas from carbohydrate 

 media. 



No characteristic odor. 



Aerobic, facultative. 



Optimum temperature 37 °C. 



Source : Feces, abscesses related to 

 intestinal tract, occasionally blood 

 stream. 



Habitat: Intestinal canal. Generally 

 considered non-pathogenic. 



la. Alcaligenes faecalis var. radicans 

 Evans (Public Health Rpts., 46, 1931, 

 1676) is a gelatin liquefying strain. 



