386 



ORDER IV. EUBACTERIALES 



minor antigen (reacting feebly) in common 

 with Shigella dysenterine. 



Source: Isolated from the stools of dysen- 

 tery patients. 



Habitat: Found in cases of human dysen- 

 tery, especiall}' in Europe; relatively un- 

 common. 



3. Shigella arabinotarda Christensen 

 and Gowen, 1944. (See Large and Sankaran, 

 Jour. Roy. Army Med. Corps, 63, 1934, 231; 

 and Sachs, Jour. Roy. Army Med. Corps, 

 80, 1943, 92; Christensen and Gowen, Jour. 

 Bact., 47, 1944, 171.) 



a.rab.i.no.tar'da. M.L. arabinosuni arab- 

 inose; L. adj. tardus late; M.L. adj. ara- 

 binotardus (probably intended to mean) 

 producing a late or slow fermentation of 

 arabinose. 



These organisms, frequently referred to 

 as the Large-Sachs Q-group, comprise six 

 recognized serotj^pes, which are known as 

 Q 771, Q 1167, Q 1030, Q 454, Q 902 and 

 599-52; there is little doubt that Dudgeon 

 and Urquhart's para-shiga is included 

 (Med. Res. Council Special Report Series 

 No. 40, 1919). 



The morphology and cultural characters 

 on agar, gelatin, broth, potato and milk are 

 identical with those of Shigella dysenteriae. 



Ladole not produced (except by serotype 

 Q902). 



Hydrogen sulfide not produced. 



Acid from glucose, galactose, fructose, 

 sorbitol and arabinose (slowlj^- No acid 

 from lactose, mannitol, dulcitol (except 

 serotype Q 1030) or rhamnose (except sero- 

 type Q902). 



Nitrites produced from nitrates. 



Trimethylamine not produced from tri- 

 methylamine oxide. 



Aerobic, facultatively anaerobic. 



Temperature relations: Optimum, 37° C. 

 No growth at 45° C. 



Antigenic structure: Each type possesses 

 a type-specific particular O antigen and 

 lacks a group antigen; therefore there is no 

 cross reaction with other species. There is a 

 thermolabile capsular L antigen which can 

 mask the O agglutination; thus diagnostic 

 tests are best with broth cultures with 

 destruction of L antigen. 



Source: Found only in the stools from 

 cases of dysentery. 



Habitat: Relatively" imcommon in out- 

 breaks of dysentery due to Shigella flexneri. 



4. Shigella boydii Ewing, 1949. (Jour. 

 Bact., 57, 1949, 634 and 635.) 



boyd'i.i. M.L. gen. noun boydii of Boyd; 

 named for Col. J. S. K. Boyd, the English 

 bacteriologist who has made a special study 

 of dysentery organisms. 



Rods. Non-motile. Some strains of sero- 

 type 2 may be encapsulated (Ewing). Gram- 

 negative. 



Gelatin: No liquefaction. 



Indole produced by serotypes 5, 7 and 11. 



Hydrogen sulfide not produced. 



Acid but no gas from mannitol (except for 

 certain strains of serotypes 3, 6 and 10), 

 glucose, arabinose and occasionally from 

 sucrose and maltose. 



Nitrites produced from nitrates. 



Antigenic structure: Shigella boydii is dis- 

 tinguished from Shigella flexneri by possess- 

 ing a type-specific major O antigen and by 

 lacking a group antigen. Some have minor 

 antigens, which fact explains their serologi- 

 cal relationships. 



Certain strains of Shigella boydii 2, 3, 5 

 and 7 may have K antigens, particularly 

 antigen L, which masks the O agglutination. 

 In this case the agglutination should be 

 made in tubes with boiled cultures (Mad- 

 sen). 



To determine the serological type, un- 

 absorbed anti-boydii 1, 2, 3 and 5 sera are 

 used, but anti-boydii 4 serum should be 

 absorbed with Shigella alkalescens and serum 

 6 with Shigella sonnei in phase II. With 

 encapsulated Shigella boydii 2, a serum 

 may be prepared which causes swelling of 

 the capsule of an organism of type 2 when a 

 capsule is present. 



There are eleven serotypes, which are 

 represented by the following recognized 

 strains: 170, P288, 5DI, P274, P143, D19, 

 Lavington, 112, 1296/7, 430 and 34. 



Relationships to other species: Shigella 

 boydii 1 has antigenic relationships with 

 serotype 4, and Shigella boydii 3 with sero- 

 type 6. However by far the most important 

 serological relationships are those of Shigella 



