182 



MANUAL OF DETERMINATIVE BACTERIOLOGY 



Habitat : Vinegar; souring fruits, vege- 

 tables and beverages. 



3. Acetobacter rancens Beijerinck. 

 {Bacterium rancens Beijerinck, Cent. f. 

 Bakt., II Abt., 4, 1898, 211; Beijerinck, 

 Krai's Sammlung v. Microorg., Prague, 

 1898, 4.) From L. rancens, being rancid. 



Beijerinck {loc. cit.) in a footnote 

 stated that "two of the many varieties of 

 B. rancens have been described by Hen- 

 neberg under the names of B. oxydans 

 and B. acetosum. Hansen erroneously 

 called this species B. aceti as did Brown. 

 Neither Hansen nor Brown knew B. 

 aceii Pasteur." No further morphologi- 

 cal description is given. 



The following description is taken in 

 part from a study of a culture of Aceto- 

 bacter rancens received from Kluyver 

 (Vaughn). 



Rods with the usual morphological ap- 

 pearance of cultures of acetic acid 

 bacteria. Gram-negative. Motility 

 variable. Motile cells possess a single 

 polar flagellum (Vaughn, Jour. Bact., 

 46, 1943, 394). Involution forms com- 

 monly appear as filaments and enlarged 

 cells. 



Wort agar slant: Growth abundant, 

 butyrous, pale-buff in color in one week. 



Yeast infusion, glucose, calcium 

 carbonate slant : Growth abundant, bu- 

 tyrous and cream-colored in one week. 



With petri dish cultures well isolated 

 colonies are large, smooth and butyrous 

 on either medium. 



Broth cultures containing peptone or 

 yeast infusion form a mucilaginous, slimj^ 

 pellicle. Beijerinck {loc. cit.) called 

 this polysaccharide pellicle, cellulose-like 

 and intimated that the mucilaginous 

 material in the pellicle was somewhat 

 different from that produced by Aceto- 

 bacter xylinum. The pellicle material 

 stained blue when treated with iodine 

 and hydroiodic acid. 



Acid from glucose, ethyl alcohol, propyl 

 alcohol, butyl alcohol, glycol, adonitol, 

 mannitol and sorbitol. No acid from 

 numerous other compounds tested. 



Distinctive character : Production of a 

 thin, mucilaginous, slimy, polysaccharide 

 membrane on the surface of liquids as 

 compared with the tMck, true cellulose 

 membrane of Acetobacter xylinum grown 

 under the same conditions. Beijerinck 

 {loc. cit.) reported the production of a 

 cellulose-like membrane with some cul- 

 tures of Acetobacter rancens. 



Source : Isolated from shavings in the 

 quick vinegar process. 



Habitat : Found in fermented grain 

 mash, malt beverages, mother of vinegar. 



Beijerinck (Cent. f. Bakt., II Abt., 4, 

 1898, 211) thought that the next two 

 species were hardly more than varieties 

 of Acetobacter rancens. 



3a. Acetobacter pasteurianum (Han- 

 sen) Beijerinck. {Mycoderma ■pasteuri- 

 anum Hansen, Compt. rend. d. Trav. d. 

 Lab. d. Carlsberg, 1, 1879, 96; Bacteriuvi 

 pasteurianum Zopf, Die Spaltpilze, 2 

 Aufl., 1884, 49; Beijerinck, Krai's Samm- 

 lung V. Microorg., Prague, 1898, 7.) 

 Named for Pasteur, the French chemist 

 and bacteriologist. 



Rods: 0.4 to 0.8 by 1.0 micron, 

 occurring singly and in chains, at times 

 showing thick, club-shaped forms. Mo- 

 tility variable. Motile cells possess a 

 single polar flagellum (Vaughn, Jour. 

 Bact., 46, 1943, 394). Stains blue with 

 iodine. 



Wort gelatin colonies: Small, circular, 

 entire, gray, slimy. 



Forms a dry, wrinkled folded pellicle 

 on double beer with one per cent alcohol. 



Meat infusion gelatin: Widespread, 

 later rosette form, toothed. 



Acid from glucose, ethyl alcohol, 

 propyl alcohol and glycol. No acid from 

 arabinose, fructose, galactose, sorbose, 

 sucrose, maltose, lactose, raffinose, 

 dextrin, starch, glycogen, inulin, methyl 

 alcohol, isopropyl alcohol, butyl alcohol, 

 isobutyl alcohol, amj'l alcohol, glycerol, 

 erythritol, mannitol, dulcitol and acetal- 

 dehyde (Henneberg, Die deutsch. Essig- 

 ind., 2, 1898, 147). 



Aerobic. 



