FAMILY XI. PROPIOXIBACTERIACEAE 



571 



uoard von Freudenreich, the Swiss bacteri- 

 ologist who isolated this species. 



Description taken from van Kiel (loc. 

 cit.) and from Werkman and Brown (Jour. 

 B&ci., 26, 1933, 397). 



Small, spherical cells, 0.5 to 0.6 micron 

 in diameter, occurring mostly in pairs and 

 short chains. Little difference in morphol- 

 ogy between growth from anaerobic solid 

 media and neutral or acid liquid media. 

 Aerobic growth irregular, club-shaped and 

 branched, long rods. Non-motile. Show met- 

 achromatic granules. Gram-positive. 



Yeast -gelatin-lactate stab: No liquefac- 

 tion. 



Yeast-agar-Iactate stab: Dirty, grayish- 

 creamy development in stab; very slight 

 surface growth of same color. 



Liquid media: Distinctly turbid with 

 grayish-creamy, ropy sediment. 



Litmus milk: Slight development; faint 

 reduction; not coagulated. 



Indole not produced. 



Ferments lactic and pyruvic acids, glyc- 

 erol, dihydroxyacetone, glucose, fructose, 

 mannose and galactose with the production 

 of chiefly propionic and acetic acids and 

 carbon dio.xide. 



Acid from erythritol, adonitol, inositol 

 and esculin. No acid from amygdalin, d- 

 and 1-arabinose, dextrin, dulcitol, glycogen, 

 inulin, lactose, maltose, mannitol, melezi- 

 tose, melibiose, perseitol, raffinose, rham- 

 nose, sucrose or xylose. 



Pantothenic acid, but not thiamine or 

 para-aminobenzoic acid, is required for 

 growth; a few strains require biotin (Del- 

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



Nitrites not produced from nitrates. 



Catalase-positive. 



Anaerobic to aerotolerant . 



Distinctive character: Inability to fer- 

 ment any of the disaccharides when inocu- 

 lated into yeast extract-sugar media. 



Source: Isolated from dairy products; 

 also from raw market milk and Swiss cheese. 



Habitat: Dairy products. 



2. Propionibacteriuni shernianii van 



Niel, 1928. {Bacterium acidi propionici d, 

 Sherman, Jour. Bact., 6, 1921, 387; van Niel, 



The Propionic Acid Bacteria, Haarlem, 

 1928, 163.) 



sher.man'i.i. M.L. gen. noun shermanii of 

 Sherman; named for J. M. Sherman, the 

 American bacteriologist who isolated this 

 species. 



Description taken from van Niel {loc. 

 cit.) and from Werkman and Brown (Jour. 

 Bact., ^6, 1933, 400). 



Small, spherical cells, 0.5 to 0.6 micron 

 in diameter, occurring mostly in pairs and 

 short chains. Little difference in morphol- 

 ogy between growth from anaerobic solid 

 media and neutral or acid liquid media. 

 Aerobic growth occurs as irregular, club- 

 shaped and branched rods. Non-motile. 

 Show metachromatic granules. Gram-posi- 

 tive. 



Yeast-gelatin-lactate stab: No liquefac- 

 tion. 



Yeast-agar-lactate stab: Dirty, grayish 

 creamy development in stab; very slight 

 surface growth of same color. 



Liquid media: Distinctly turbid with 

 grayish -creamy, ropy sediment. 



Litmus milk: Acid coagulation. 



Indole not produced. 



Ferments lactic and pyruvic acids, glyc- 

 erol, dihydroxyacetone, glucose, fructose, 

 mannose, galactose and lactose with the 

 production of chiefly propionic and acetic 

 acids and carbon dioxide. Occasionally 

 arabinose is fermented. 



Acid from erythritol, adonitol, arabitol, 

 inositol and esculin. No acid from amj^g- 

 dalin, dextrin, dulcitol, glycogen, inulin, 

 maltose, mannitol, melezitose, melibiose, 

 perseitol, raffinose, rhamnose, salicin, sorbi- 

 tol, sucrose, starch, trehalose or xylose. 



Pantothenic acid and biotin, but not 

 para-aminobenzoic acid, are required for 

 growth; some strains require thiamine, 

 others do not, and still others find this vita- 

 min stimulating but not required for growth 

 (Delwiche, Jour. Bact., 58, 1949, 396). 



Nitrites not produced from nitrates. 



Catalase-positive. 



Anaerobic to aerotolerant. 



Distinctive characters: Resembles Fro- 

 pionibactenum Jreudenreichii in every re- 

 spect, but differs in its ability to ferment 

 lactose. 



