902 MISCELLANEOUS BACTERIA 



Indole is not formed ; nitrates are reduced to nitrites ; and gelatin is not liquefied. It 

 is destroyed by heat at 57° C. in 10 minutes (Olitsky 1930). The organism is non-patho- 

 genic for laboratory animals, but when inoculated subconjunctivally into rhesus monkeys 

 it gives rise to a granular conjunctivitis simulating trachoma (see Chapter 85). (For 

 a fuller description of this organism see Noguchi 1928, Tilden and Tyler 1930.) 



A Gram-negative bacillus simulating Bad. granulosis in many resjiects has been described 

 under the name of Bad. simice by OUtsky, Syverton, and Tyler (1933), who isolated it 

 from monkeys suffering from spontaneous conjunctival foUiculosis. Like Bad. granulosis, 

 which it resembles in size, it is motile by a single polar flagellum, produces a nebulous 

 opacity in leptospiral medium, fails to grow anaerobically, has an optimum growth tem- 

 perature of 30° C, and is non- pathogenic for laboratory animals. It differs, however, 

 from this organism in having a capsule, in growing on plain nutrient agar, in fermenting 

 different carbohydrates, in failing to reduce nitrates, and in showing no agglutination with 

 granulosis antisera. What relation Bad. granulosis and Bad. simice bear to Ducrey's 

 bacillus, and to the less exacting members of the Hcemophilus group, has still to be 

 determined. 



Bact. alkaligenes and Vibrio alkaligenes. 



Petruschky (1896) isolated from human faeces an organism that produced an 

 alkaline reaction in certain media, and was named by him Bact. fcecalis alkaligenes. 

 It was described as a Gram-negative bacillus, and has long been included by most 

 authorities in the genus Bacterium under the name of Bact. alkaligenes. Though it 

 appears to be an almost constant inhabitant of the intestinal tract of man, this 

 organism may give rise to infections of the enteric type (Petruschky 1896, Hirst 

 1917, Khaled 1923). 



The characters usually ascribed to Bad. alkaligenes are as follows : The cells are very 

 variable in size, but are usually longer and thinner than those of Bad. coli (5-7 [i x 0-4 fx), 

 and the ends are less definitely rounded. The bacilli are motile, with peritrichate flagella. 

 The colonies on agar are flatter than those of Bad. coli, and more contoured, with a raised 

 central portion and a spreading undulate edge. Neither acid nor gas is produced in any 

 of the usual test substrates. Litmus milk is rendered strongly alkaline. A characteristic 

 brown -colour is produced on potato. 



Many of these characters are very unlike those of the genus Baderium, and doubts 

 have been frequently expressed as to its real systematic affinities. A recent study by 

 Nyberg ( 1935) raises even stronger doubts as to whether the strains that have been described 

 under this name can be regarded as forming a bacterial species. Nyberg examined with 

 great care 134 strains labelled Bad. alkaligenes, and was able to distinguish among them 

 two quite distinct forms, and a number of less well-differentiated types. The form for 

 which he would reserve the name Bad. alkaligenes is a short, thick bacillus, usually non- 

 motile or very feebly motile, but possessing in most cases poorly formed peritrichate 

 flagella. It fails to ferment dextrose, Isevulose, lactose, maltose, saccharose, rhamnose, 

 xylose, arabinose, mannitol, sorbitol, dulcitol, inositol or salicin. It does not form indole, 

 and it produces no change in milk. Of the 134 strains examined, 71 were of this type. 

 Nyberg notes that this description does not agree with that given of Bad. alkaligenes in 

 many books and papers, and that it is impossible to be certain that his strains correspond 

 to the organism originally isolated by Petruschky. He considers, however, that they 

 probably belong to the same species, and that the name must certainly be given to them 

 and not to the type to which his other strains belong. 



This second type is a long, thin, slightly curved rod, actively motile by lophotrichate 

 flagella. It is therefore not a bacillus, but a vibrio. UnUke the former type, it renders 

 a dextrose medium slightly but definitely alkaline. Nyberg regards this organism as 

 identical with the Vibrio alkaligenes of Lehmann and Neumann (1896) ; and there would 

 seem no doubt that this is its proper name. It also seems very probable, as Nyberg 



