Phylum Actinobacteria, Class Actinobacteria, Subclass Actibacteridae, Order Actynomycetales, Suborder Corynebacterinae, Family
Corynebacteriaceae, Genus Corynebacterium, Corynebacterium flavescens Barksdale, Laneele, Pollice, Asselineau, Welby and
Historical synonyms: Microbacterium flavum Orla-Jensen 1919, Mycobacterium flavum (Orla-Jensen 1919) Jensen 1934.
Gram-positive to Gram-variable pleomorphic rods which exhibit moderately tapered ends; when grown on phosphate-rich medium,
cells contain metachromatic granules which can be revealed by staining with alkaline methylene blue or toluidine blue. Non-motile.
Colonies on BHI agar are smooth, butyrous, and cream colored; on Loeffler medium
inspissated serum slants, growth appears yellow. On tellurite agar the colonies are
grayish black; 10-day-old colonies are characterized by leached (grayish-white)
centers. Growth on galactose agar has a yeasty odor. Not grow on minimal media
(Sauton medium). Abundant growth is produced in a basal medium plus glutamic
acid, isoleucine, methionine, proline, para-aminobenzoic acid, biotin, nicotinic acid,
pantothenic acid, and thiamine.
Aerobic, facultative anaerobic. Grows in 2.5% and 5% NaCl media. Weak growth in
10% NaCl. No growth in 15.5% NaCl.
Found mainly in dairy products and on dairy utensils.
- Barksdale L., Laneelle M.A., Pollice M.C., Asselineau J., Welby M. and Norgard M.V., 1979. Biological and Chemical Basis for the
Reclassification of Microbacterium flavum Orla- Jensen as Corynebacterium flavescens nom. nov. Int .J. Syst. Bacteriol. Vol. 29,
No. 3, p. 222-233.
- Holt J.G., Krieg N.R., Sneath P.H.A., Staley J.T. and Williams S.T., 1994. Bergey's Manual of Determinative Bacteriology, Ninth
Edition, Williams & Wilkins, A Waverly Company, Baltimore, pp 571-596.
- Rogosa M. and Keddie R.M., 1975. Genus B Microbacterium Orla-Jensen 1919 . In: Buchanan R.E. and Gibbons N.E. (Editors),
Bergey’s Manual of Determinative Bacteriology, Eight Edition, The Williams & Wilkins Company, Baltimore, 628-629.
Positive results for catalase, methyl red reduction, Voges-Proskauer test, acid production from: fructose, galactose, glucose, mannitol
Negative results for alkaline phosphatase, casein hydrolysis, gelatin hydrolysis, H2S production, hippurate hydrolysis, lysine
decarboxylase, nitrate reduction, ornithine decarboxylase, phenylalanine deaminase, pyrazinamidase, starch hydrolysis, Tween 80
hydrolysis, urease, acid production from: adonitol, arabinose, dextrin, dulcitol, glycerol, inositol, inulin, lactose, maltose, melibiose,
raffinose, rhamnose, salicin, sorbitol, starch, sucrose, trehalose & xylose.
(c) Costin Stoica