414 ORDER IV. EUBACTERIALES 



Genus V. Actinobacillus Brumpt, 1910* 



(Brumpt, Precis de Parasitologie, Paris, 1st ed., 1910, 849; Cladascus Enderlein (in part), 

 Sitzber. Ges. Naturf. Freunde, Berlin, 1917, 316; PJeifferella Buchanan, Jour. Bact., 3, 

 1918, 54; not PJeifferella Labl)e, Sporozoa, in Das Tierreich, Lief. 5, 1899, 60; MaUeomyces 

 Pribram, Klassifikation der Schizomyceten, Leipzig, 1933, 11 and 93; not MaUeomyces 

 Hallier, Ztschr. f. Parasitenkunde, 1870, 119; Loefflerella Gay et aL, Agents of Disease and 

 Host Resistance, Indianapolis, 1935, 782.) 



Ac.ti.no.ba.cil'lus. Gr. noun actis, actinis a ray, beam; L. dim. noun bacillus a small rod; 

 M.L. noun Actinobacillus ray bacillus or rod. 



Small to medium-sized, coccoid to rod-shaped cells which rarely grow into filaments; 

 under special conditions the filaments may show some branching. Non-motile. There is a 

 tendency to show bipolar staining. Gram-negative. Colonies may be mucous or stringy, 

 especially when freshlj^ isolated, and white, grayish white, yellowish or bluish in color. 

 Aerobic to facultatively anaerobic. Microaerophilic in primary cultures. Acid but no gas 

 from carbohydrates, when fermented. Pathogenic for animals; some species attack man. 



The type species is Actinobacillus lignieresii Brumpt. 



Key to the species of genus Actinobacillus. 



I. Little or no growth on potato. 



A. Growth in milk. 



1. Nitrites not produced from nitrates. Non-pigmented growth on glycerol agar. 



1. Actinobacillus lignieresii. 



2. Nitrites produced from nitrates. 



2. Actinobacillus equuli. 



B. No growth in milk. 



1. Growth on ordinary agar or broth. 



3. Actinobacillus actinomycetemcomitans. 



2. No growth on ordinary agar or broth. 



4. Actinobacillus actinoides. 

 II. Good growth on potato. Yellowish growth on glycerol agar. 



5. Actinobacillus mallei. 



1. Actinobacillus lignieresii Brumpt, forms occur. Non-motile. Frequentl}^ show 



1910. (Actinobacilo, Lignieres and Spitz, bipolar staining. Gram-negative. 

 Boletin d. Agr. 3^ Ganaderia, Buenos Aires, Gelatin: Growth sparse, if at all. No 



11, 1902, 169; Actinobacille, Lignieres and liquefaction. 



Spitz, Cent. f. Bakt., I Abt., Orig., 35, Infusion-peptone-agar: Good growth, 



1903, 454; Actinobacillus Lignieresi (sic) favored by the addition of serum or blood. 



Brumpt, Precis de Parasitol., Paris., 1st Primary cultures succeed w^hen granules 



ed., 1910, 849.) are broken. Surface colonies measure 1 mm 



lig.ni.e.re'si.i. M.L. gen. noun lignieresii and may reach 2 to 3 mm in diameter; 



of Lignieres; named for J. Lignieres, one translucent and bluish, later opaque, 



of the bacteriologists who first isolated this Colonies in primary isolations may be 



organism. rather firmly attached to the agar surface; 



Rod-shaped cells, 0.4 by 1.15 to 1.25 when touched by the tip of the needle a 



microns, on primary isolation; later, espe- ropy thread may be pulled off, the colony 



cially on agar, cocco-bacillary and diplococ- finally jerking to the tip of the needle leav- 



cal forms occur. Streptobacillary forms ing a rough spot on the agar surface. In 



appear in serum broth, and in old cultures, subcultures the ropiness gradually is lost, 



principally in serum broth, involution but the growth continues to be mucous. 



* Prepared by Prof. Dr. H. Haupt, University of Giessen, Giessen, Germany, April, 1955. 



