400 



ORDER IV. EUBACTERIALES 



granular or beaten-copper surface; differ- 

 entiated into a raised, more opaque center 

 and a flat, clearer periphery with radial 

 striation. 



Agar slant: After 48 hours at 37° C, 

 growth moderate, confluent, raised, grayish 

 yellow, translucent, with glistening, wavy 

 or beaten-copper surface and an irregularly 

 lobate edge. 



Blood agar plate: Good growth. No he- 

 molysis. 



Broth: After 24 hours at 37° C, moderate 

 growth with moderate turbidity which 

 later clears. Viscous sediment. Incomplete 

 surface and ring growth. Becomes alkaline 

 more rapidly than does Pasteur ella pestis. 

 ^ Litmus milk: Usually slightly alkaline. 



Potato: After 7 days at 22° C, a thin, 

 yellowish membrane appears which later 

 turns brown. 



Indole not produced. 



Hydrogen sulfide produced. 



Acid but no gas from glucose, maltose, 

 arabinose, xylose, rhamnose, salicin, glyc- 

 erol and mannitol. Sometimes acid from 

 sucrose. 



Methyl red test positive. 



Acetylmethylcarbinol not produced. 



Nitrites produced from nitrates. 



Ammonia is produced. 



Methylene blue is reduced. 



Catalase-positive. 



Aerobic, facultatively anaerobic. 



Temperature relations: Optimum, 30° C. 

 Minimum, 5° C. Maximum, 43° C. Thermal 

 death point, 60° C. for 10 minutes. 



Pathogenicity: Infectious for mice, rats, 

 dogs, cats and horses. 



Distinctive characters: Motile with peri- 

 trichous flagella and H antigen at 22° C; 

 non-motile, non-flagellated and no H 

 antigen at 37° C; this change occurs near 

 30° C; non-motile strains grown at 37° C. 

 develop flagella when grown at 22° C. 

 (Preston and Maitland, Jour. Gen. Micro- 

 biol., 7, 1952, 117). 



Comments: See description of Pasturella 

 pestis for comments regarding the difTer- 

 entiation of these two species. 



Source: Isolated from a guinea pig inocu- 

 lated with material from a horse suspected 

 of having glanders. 



Habitat: Schiitze (Syst. of Bact. in 



Relation to Med., Med. Res. Counc, Lon- 

 don, 4, 1929, 474) states that this species 

 appears to be widely distributed in nature, 

 having been found in soil, dust, water, fodder 

 and milk. It causes pseudotuberculosis in 

 the following animals: horse, cow, goat, 

 rabbit, hare, guinea pig, mouse, wild rat, 

 cat, dog, monkey, hen, turkey, pigeon and 

 canary. The organism has been isolated 

 from human blood, spleen, liver, gall blad- 

 der, appendix and cerebro-spinal fluid. 



8. Pasteurella tularensis (McCoy and 

 Chapin, 1912) Bergey et al., 1923. (Bac- 

 terium tularense McCoy and Chapin, Jour. 

 Inf. Dis., 10, 1912a, 61; McCoy and Chapin, 

 Public Health Bull. 53, U. S. Treas. Dept., 

 Public Health Service, 1912b, 17; Bergey 

 et al.. Manual, 1st ed., 1923, 267.) 



tu.la.ren'sis. M.L. adj. tularensis per- 

 taining to Tulare County; named for 

 Tulare, the county in California in which 

 tularemia was first observed. 



Description taken from McCoy and 

 Chapin (op. cit., 1912a, 61, and op. cit., 

 1912b, 17) and from Francis (U. S. Hygienic 

 Lab. Bull. 130, 1922). Further revision by 

 Francis, 1947. 



Equal numbers of cocci and rods; 0.2 by 

 0.2 to 0.7 micron, occurring singly. Ex- 

 tremely pleomorphic (Hesselbrock and 

 Foshay, Jour. Bact., 49, 1945, 209). Capsules 

 rare or absent. Non-motile. May show bi- 

 polar staining. Gram-negative. 



No growth on plain agar or in liquid media 

 without special enrichment (Tamura and 

 Gibby, Jour. Bact., 45, 1943, 361). Filtera- 

 ble through Berkefeld filters. 



Growth occurs on coagulated egg yolk 

 (McCoy and Chapin), on blood glucose 

 cystine agar (Francis), on blood agar, 

 glucose blood agar and glucose serum agar. 

 The addition of fresh, sterile rabbit spleen 

 to the surfaces of the last three media favors 

 the growth of the organism. 



Forms minute, viscous colonies after 2 to 

 5 days which may attain a diameter of 4 

 mm if well separated. Growth readily 

 emulsifiable. 



Growth on blood media is gray. May cause 

 green discoloration of the blood. 



Rough, smooth and mucoid variants have 

 not been reported. 



