Actinobacillus pleuropneumoniae (pinpoint
colonies) dependent of V factor (NAD) - producing
Staphylococcus aureus (yellow line)
Actinobacillus pleuropneumoniae
Cultural characteristics
Biochemical characters
Phylum Proteobacteria, Class Gammaproteobacteria, Order Pasteurellales, Family Pasteurellaceae, Genus Actinobacillus,  
Actinobacillus pleuropneumoniae
Pohl, Bertschinger, Frederiksen and Mannheim 1983.
Biovar 1 (V-factor-dependent strains previously classified as
H. pleuropneumoniae; 14 serovars) & Biovar 2 (V-factor-independent
Haemophilus pleuropneumoniae Shope 1964.
Gram-negative cells, nonmotile, nonspore-forming, small, coccoid to rod-shaped,
occurring singly, in pairs, or in short chains.
Colonies are grayish white  and smooth on chocolate agar; 3 mm in diameter after 48
hours  in candle jar at 37 ºC.
Beta hemolysis, but may be very slight or absent. CAMP test is positive.
V-factor dependency is variable ( Biovar 1 (V-factor-dependent strains previously
classified as
H. pleuropneumoniae) & Biovar 2 (V-factor-independent strains)).
Aerobic, microaerophilic in primary isolation , facultatively anaerobic; no additional
2 is required for growth in subculture.
Mesophilic. Chemoorganotrophic , with pronounced growth response to fermentable
carbohydrates in peptone media.
Growth on MacConkey agar is negative.
Biovar 1 causes the porcine pleuropneumonia, a highly contagious respiratory infection.
Most efficient antibiotics against  
A. pleuropneumoniae strains isolated from diseased piglets in Romania were ampicillin, amoxicillin
and gentamicin (100% of the tested strains were susceptible to this antibiotics).
Biovar 1 causes the porcine pleuropneumonia, a highly contagious respiratory infection. This severe and often fatal (fibrinous)
hemorrhagic bronchopneumonia leds to significant economic losses.
A. pleuropneumoniae produces three RTX toxins (Apx I,II,III), transferrin-binding proteins and urease. Other virulence factors: capsular
polysaccharide, cellular lipopolysaccharide and outer membrane proteins.
  1. Olsen I., MØller K., 2004. Genus II. Actinobacillus. In: Bergey’s Manual of Systematic Bacteriology, Second edition, Vol two, part B,
    George M. Garrity (Editor-in-Chief), pp. 866-883.
  2. W.M. Janda, R. Mutters, 2006. Pasteurella, Mannheimia, Actinobacillus, Eikenella, Kingella, Capnocytophaga, and other
    miscellaneous Gram-negative rods. In: Topley & Wilson’s Microbiology and Microbial Infections, 10 edition, Vol. 2, Bacteriology,
    Edward Arnold Ltd.
  3. J. G. Holt et al., 1994. Facultatively Anaerobic Gram-Negative Rods. Subgroup 3. Family Pasteurellaceae. In: Begey’s Manual of
    Determinative Bacteriology, 9th-edition, Williams & Wilkins, pp 194-196.
  4. Sorescu I., 2002, Pleuropneumonia infectioasa a porcului: date recente privind etiopatogeneza si imunoprofilaxia. Buletin
    informativ in patologie porcina, V, 1, 48-50.
  5. Sorescu I., Stoica C., Drăghici D.,Stănuică D., 2001. Sensibilitatea la antibiotice si chimioterapice a tulpinilor de E. coli,
    Salmonella choleraesuis grup C, Pasteurella multocida si Actinobacillus pleuropneumoniae izolate de la porcine in intervalul  
    aprilie 2001 - septembrie 2001. Buletin informativ in patologie porcina, IV, 1, 23-27.
  6. Sorescu I., Stănuică D., Luminiţa Romaşcu, Vyan Zangana, 2002. Sensibilitatea la antibiotice şi chimioterapice a tulpinilor de
    Escherichia coli, Salmonella choleraesuis grup C, Pasteurella multocida, Mannheimia spp. (Pasteurella haemolytica),
    Actinobacillus pleuropneumoniae, Haemophilus parasuis şi Streptococcus spp. izolate de la porcine în intervalul Ian-Oct 2002,
    Buletin informativ in patologie porcina,  V, 4, 3-8.
Positive results for nitrates reduction, alkaline phosphatase, H2S production, ONPG,
acid production from: D(+) xylose, mannitol, D(-) fructose, urease, D(+) galactose, D
(+) mannose, maltose, sucrose & D(+) glucose (without gas).

Negative results for Voges-Proskauer reaction, arginine dehydrolase, lysine
decarboxylase, ornithine decarboxylase, indole production, acid production from:
glycerol, L(+) arabinose, dulcitol, meso-inositol, D(-) sorbitol, L(+) rhamnose, L(-)
sorbose, cellobiose, melibiose, trehalose, inulin, esculin & salicin.

Variable results for oxidase, catalase, lactose & raffinose.
(c) Costin Stoica
Culture media
Biochemical tests
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