FAMILY ENTEROBACTERIACEAE 



539 



Source : Isolated in 1925 from a case of 

 diarrhoea in Xewcastle-on-Tyne, Eng- 

 land . 



Habitat : A cause of human dysentery. 



4b. Shigella paradysenteriae (Tj'pe 

 Manchester). (Downie, Wade and 

 Young, Jour. Hyg., 33, 1933, 196; Bacil- 

 lus dysenteriae Flexner VI in part, Boj^d, 

 Trans. Roy. Soc. Trop. Med. and Hyg., 

 33, 1940, 553.) 



Characters as for Type Xewcastle ex- 

 cept that acid and gas are produced 

 from mannitol. Does not produce gas 

 from maltose. 



Serologically related to the non-manni- 

 tol-fermenting strains of Shigella para- 

 dysenteriae. 



Source : Five strains were isolated from 

 cases of dysentery at Denton near ^Nlan- 

 chester, England. One strain came 

 from a case of dysentery in Nigeria. 



Habitat: A cause of human dysentery. 



5. Shigella alkalescens (Andrewes) 

 Weldin. {Bacillus alkalescens An- 

 drewes, The Lancet, London, 19i, 1918, 

 560; Bacterium alkalescens Levine, Jour. 

 Inf. Dis., 27, 1920, 31; Eherthella alka- 

 lescens Bergey et al.. Manual, 1st ed., 

 1923, 231; Weldin, Iowa State College 

 Jour. Sci., /, 1927, 179; Proshigella alka- 

 lescens Borman, Stuart and Wheeler, 

 Jour. Bact., 48, 1944, 363.) From the 

 chemical term, alkaline. 



Rods: 0.5 by 1.0 to 1.5 microns, occur- 

 ring singly and in pairs. Non -motile. 

 Gram-negative. 



Gelatin stab: Xo liquefaction. 



Agar slant: Abundant, transparent, 

 often iridescent growth. 



Broth: Turbid. 



Litmus milk: Acid, then alkaline. 



Potato: Moderate, grayish growth. 



Indole is formed. 



Acid but no gas from glucose, xjdose, 

 rhamnose, maltose, mannitol and dulci- 

 tol. Sucrose is fermented by some 

 strains. Does not attack lactose, dex- 

 trin or salicin. 



Reduces trimethylamine oxide to tri- 



methylamine (Wood et al., Jour. Bact., 

 46, 1943, 106). In contrast to all other 

 species of the genus, will also produce 

 trimethylamine from choline (Wood and 

 Keeping, Jour. Bact., 47, 1944, 309). 



Aerobic, facultative. 



Optimum temperature 37°C. Grows 

 at 45.5°C (Eijkman's reaction, Stuart 

 et al., Jour. Bact., 46, 1943, 105). 



Not pathogenic. Not agglutinated 

 by Shiga immune serum. 



Source: From feces in cases of dysen- 

 tery. 



Habitat: Intestinal canal. 



6. Shigella pfaffii (Hadley etal.) Wel- 

 din. (Bacillus der kanarienvogelseuche, 

 Pfaff, Cent. f. Bakt., I Abt., Orig., 38, 

 1905, 276; Bacterium pfaffi Hadley, El- 

 kins and Caldwell, Rhode Island Agr. 

 E.xp. Sta. Bull. 174, 191S, 169; Bacillus 

 pfaffi Hadley, Elkins and Caldwell, 

 ibid.. 204; Eherthella pfaffi Bergey et al.. 

 Manual, 1st ed., 1923, 232; Weldin, 

 Iowa State College Jour. Sci., 1, 1927, 

 180.) Named for Dr. Franz Pfaff of 

 Prague who isolated this species. 



Description largely from Hadley et al. 

 {loc. cit., 180). 



Rods: 0.5 by 1.0 to 2.0 microns, occur- 

 ring singly. Non-motile. Gram-nega- 

 tive. 



Gelatin colonies : Small, grayish, trans- 

 lucent. 



Gelatin stab: No liquefaction. 



Agar colonies: Small, yellowish-gray, 

 homogeneous, translucent, entire. No 

 odor. 



Agar slant: Slight, yellowish-gray, 

 translucent streak. 



Broth: Turbid, with flocculent sedi- 

 ment (Pfaff, loc. cit., 280). 



Litmus milk: Unchanged. 



Potato: Moderate, whitish streak. 



Acid but no gas from glucose, fructose, 

 arabinose, xylose, maltose, dextrin, 

 salicin and mannitol. Does not attack 

 lactose, sucrose, raffinose, inulin, adoni- 

 tol or dulcitol. 



Indole not formefl. 



No hydrogen sulfide produced. 



