FAMILY XI. PROPIONIBACTERIACEAE 



575 



growth, dry and wrinkled, resembling that 

 of Mycobacterium spp. 



Liquid media: No turbiditj^; sediment a 

 coherent layer, cream-colored. 



Litmus milk: Acid coagulation. 



Indole not produced. 



Ferments lactic and pyruvic acids, glyc- 

 erol, dihydroxyacetone, glucose, fructose, 

 mannose, galactose, sucrose, maltose and 

 lactose with the production of propionic 

 and acetic acids and carbon dio.xide. 



Acid from esculin and salicin. No acid 

 from d- and 1-arabinose, cellobiose, dextrin, 

 dulcitol, glycogen, inulin, perseitol, pectin, 

 raffinose, rhamnose, sorbitol, starch or xj^- 

 lose. 



Pantothenic acid, biotin and para-amino- 

 benzoic acid are required for growth; thi- 

 amine, while not required, is stimulating 

 for growth (Delwiche, Jour. Bact., 58, 1949, 

 396). 



Nitrites not produced from nitrates. 



Catalase-positive; aerobically developed 

 growth very slightly so. 



Less anaerobic than Propionibacterium 

 freudenreichii and Propionibacterium sher- 

 manii. 



Distinctive character: Growth in liquid 

 media in clumps, giving the cultures the 

 appearance of agglutinated bacteria. So far 

 as known, the only species among the pro- 

 pionic acid bacteria possessing this char- 

 acteristic. 



Source: Isolated from cheese and soil. 



Habitat: Dairy products. 



9. Propionibacterium jensenii van 



Niel, 1928. {Bacterium acidi propionici b, 

 von Freudenreich and Orla-Jensen, Cent. f. 

 Bakt., II Abt., 17, 1906, 532; van Niel, The 

 Propionic Acid Bacteria, Haarlem, 1928, 

 163.) 



jen.se'ni.i. M.L. gen. noun jensenii of 

 Jensen; named for Prof. S. Orla-Jensen, the 

 Danish bacteriologist who isolated this 

 organism. 



Description taken from van Niel (loc. 

 cit.) and from Werkman and Brown (Jour. 

 Bact., 26, 1933, 404). 



In neutral media spherical to short rod- 

 shaped cells, 0.8 by 0.8 to 1.5 microns, occur, 

 often in pairs or short chains; possess typi- 

 cal diphtheroid appearance. Morphology 



little influenced by developing acidity. 

 Aerobic growth occurs as irregular long 

 rods, swollen and branched. Non-motile. 

 Show metachromatic granules. Gram-posi- 

 tive. 



Yeast-gelatin-lactate stab: No liquefac- 

 tion. 



Yeast-agar-lactate stab: Cream-colored 

 growth in stab; orange-yellow, dome-shaped 

 surface growth. 



Liquid media: Turbid in early stages; 

 cream-colored, smooth sediment. 



Litmus milk: Coagulated, acid. 



Indole not produced. 



Ferments lactic and pyruvic acids, glyc- 

 erol, dihydroxyacetone, glucose, fructose, 

 mannose, galactose, sucrose, maltose, lac- 

 tose and sometimes raffinose and mannitol 

 with the production of propionic and acetic 

 acids and carbon dioxide. 



Acid from adonitol, arabitol, erythritol. 

 esculin, inositol and trehalose. No acid from 

 arabinose, cellobiose, dextrin, dulcitol, gly- 

 cogen, inulin, perseitol, pectin, rhamnose, 

 salicin, sorbitol, starch or xylose. 



Pantothenic acid and biotin are growth 

 requirements; some strains require para- 

 aminobenzoic acid, others do not, and still 

 others find this vitamin stimulating but 

 not required for growth; thiamine, although 

 not required, is growth-stimulating (Del- 

 wiche, Jour. Bact., 58, 1949, 396). 



Nitrites not produced from nitrates. 



Strongly catalase-positive. 



Less anaerobic than Propionibacterium 

 freudenreichii. 



Distinctive characters: Morphologically 

 similar to Propionibacterium rubrum and 

 Propionibacterium thoenii from which it is 

 distinguished chiefly by the failure to pro- 

 duce a red pigment under anaerobic condi- 

 tions. The yellow surface growth distin- 

 guishes Propionibacterium jensenii from 

 Propionibacterium zeae, as does also the 

 inability of the former to ferment 1-arabi- 

 nose and rhamnose. 



Source: Isolated from cheese and butter. 



Habitat: Dairy products. 



10. Propionibacterium arabinosum 



Hitchner, 1932. (Jour. Bact., SS, 1932, 40; 

 also see ibid., 28, 1934, 473.) 



a.ra.bi.no'sum. Gr. noun Arabia Arabia; 



