19. Vibrio 



The genus Vibrio is composed of bacteria which typically have 

 a slight somatic cm-vature and a single polar flagellum (Fig. 21). 

 The somatic curvature is an unreliable characteristic which has, 

 perhaps, little taxonomic significance. Carbohydrates are fermented 

 with acid production but no gas. Most strains are very proteolytic, 

 actively liquefying gelatin and coagulated serum. Bergey's Manual, 

 6th ed., recognizes twenty-two species. Several of these species 

 are definitely out of place in the genus, such as Vibrio percolans 

 (Lophomonas) and Vibrio cimeatus (Pseiidomonas). Several other 

 species obtained from culture collections had peritrichous flagella 

 and therefore are not Vibrio species. These latter, of course, may 

 have been contaminants which had replaced the original vibrios. 

 In this category may, perhaps, be Vibrio jejuni, ATCC 11734, which 

 had peritrichous flagella. 



Fig. 21. a. Vibrio cholerae, Freter 144. Typical specimen showing polar 

 monotrichous flagellation. 



b. V. proteus. This picture is of an old stock strain labeled V. finklur-prior. 



c. Vibrio { Pseud omonas) rubicundus, Haynes B-782. This organism is 

 more properly classified as Pseiidomonas sp. since it did not attack carbo- 

 hydrates. 



d. V. tyrogeniis, Haynes B-1033. The soma of this organism often re- 

 sembled a spirilkim with several curves. A very few individuals had multiple 

 flagella at one pole. 



e. f. Vibrio sp., MacLeod MB-26. This is a halophilic vibrio from the 

 Pacific Ocean. The organisms with the straight soma were more numerous 

 than those with a curved soma. 



g, h. V. fetus, Hansen. Most of the individuals in the culture studied 

 showed polar monotrichous flagellation illustrated in g. A fair number showed 

 polar multitrichous flagellation illustrated in h. The resemblance to spirilla is 

 striking. 



i, j. V. fetus, Rylf 28099. In i is shown an organism with several curves like 

 a spirillum. In j is shown the rounded types or "microcysts" so typical of 

 spirilla. 



k, 1. V. coli, Di Liello 505. The organism illustrated in 1 is in the process 

 of microcyst formation. 



m. V. coli, Di Liello 498. The bipolar flagellation was common in the 

 V. coli cultures as it was in the V. fetus cultures. 



n. Vibrio (?) jejuni, ATCC 11734. This is obviously not a Vibrio sp. In 

 the culture studied the soma was generally curved as illustrated. The peri- 

 trichous flagellation is unmistakable. Cultures other than this could not be 

 obtained. 



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