Taxonomy
Morphology
Cultural characteristics
Biochemical characters
Ecology
Pathogenicity
References
Phylum Actinomycetota, Class Actinomycetes, Order Mycobacteriales, Family Corynebacteriaceae, Genus Corynebacterium,
Corynebacterium durum Riegel, Heller, Prevost, Jehl and Monteil 1997.
Gram-positive long, pleomorphic rods (3 to 4 µm long) or occasionally filaments (15
to 30 µm long) with swollen ends. Nonmotile. Nonspore-forming.
After 48-72 h of incubation on blood agar plates in an aerobic atmosphere at 37 ºC,
cultures appeared as small (up to 1 mm), convoluted, convex, rough, raised beige
colonies with irregular edges and no hemolytic activity. Strong adherence to the
medium occurred; in an aerobic atmosphere supplemented with 10% CO2, exhibited
larger colonies with a dense center, nearly regular margins and slightly adherent to
agar. Weak anaerobic growth.
In liquid media, the organisms produce a sediment, leading to a granular
appearance of the culture after the broth was shaken.
Isolated from respiratory tract specimens of human patients with a history of pneumonia.
Susceptible to ampicillin, amoxicillin-clavulanic acid, piperacillin, cefotaxime, gentamicin, ciprofloxacin, minocycline, erythromycin,
rifampin, teicoplanin and vancomycin.
Undetermined.
- Riegel P., Heller R., Prevost G., Jehl F. and Monteil H. 1997. Corynebacterium durum sp. nov., from human clinical specimens.
IJSB Vol. 47, No.4, 1107-1111.
- Funke G., 2006. Corynebacteria and rare coryneforms. In: Topley & Wilson’s Microbiology & Microbial Infections, 10th Edition,
Edited by Borriello S.P., Murray P.R. and Funke G., Edward Arnold (Publishers) Ltd., Bacteriology, volume 2.
Fermentative metabolism. Non-partially-acid-fast.
Description of most biochemical test is based on API CORYNE.
Positive results for nitrate reduction, pyrazinamidase, acid production from: fructose, galactose, glucose, maltose, mannitol and
sucrose.
Negative results for alkaline phosphatase, alpha-glucosidase, beta-galactosidase, beta-glucuronidase, gelatin hydrolysis,
lipophilism, tyrosine hydrolysis, acid production from: lactose, ribose, trehalose and xylose.
Weak and variable results for esculin hydrolysis and urease.
(c) Costin Stoica