FAMILY IV. ENTEROBACTERIACEAE 



345 



Agar colonies: White, shiny, convex, 

 smooth, glistening, entire. 



Agar slants: Slimy, white, somewhat 

 translucent, raised growth. 



Broth: Turbid; thick ring or film. 



Litmus milk: Acid; no coagulation. 



Potato: Yellowish, slimy, raised growth. 

 Gas is produced. 



Indole not produced. 



Hydrogen sulfide not produced. 



Acid and gas from glucose. Acid and gas 

 may be produced from lactose. Acid from 

 sucrose, maltose, salicin, arabinose, rham- 

 nose, xylose, mannitol, adonitol, inositol 

 and sorbitol. Acid may or may not be pro- 

 duced from dulcitol. 



Acetylmethylcarbinol usually produced. 



Methyl red test negative. 



Ammonium citrate utilized as a sole 

 source of carbon. 



Nitrites produced from nitrates. 



Urea maj' or may not be slowh' decom- 

 posed. 



Aerobic, facultatively anaerobic. 



Optimum temperature, 37° C. 



Pathogenicity: Lethal for mice. 



Serology: Cultures belonging to this 

 species are classified serologically on the 

 basis of their O and K (capsule) antigens. 

 Kauffmann (Acta Path, et Microbiol. 

 Scand., 26, 1949, 38) and 0rskov (Acta Path, 

 et Microbiol. Scand., 34, 1954, 145) demon- 

 strated four somatic groups in the kleb- 

 siellas, in each of which was found a variety 

 of capsular antigens. Due to technical 

 difficulties caused by the prominent cap- 

 sules possessed by most cultures, the O 

 antigens of Klebsiella cultures usually are 

 not determined, and serological examina- 

 tion is confined to the determination of the 

 capsular antigens of the strains. Through 

 the work of a number of investigators, 72 

 capsule types have been recognized. Of 

 these, types 1 to 6 inclusive (A to F of the 

 earlier literature) occur in the respiratory 

 tract of man and occasionally are found in 

 other locations. The remaining capsule 

 types exhibit no such preference and are 

 widely distributed in nature. They occur 

 frequently in respiratory and urinary in- 

 fections, in the blood stream and in feces. 



Comment : From the foregoing, it may be 

 seen that no method has been found to 



differentiate the majority of Klebsiella 

 pneumoniae cultures from organisms com- 

 monly classified as Aerobacter aerogenes, 

 and this situation has caused confusion. 

 Identical cultures are classified bj^ some 

 workers as types of Klebsiella pneumoniae 

 and by others as Aerobacter aerogenes. The 

 source from which an organism was isolated 

 often has dictated the genus into which it is 

 placed. Until such time as the relationships 

 of the two genera are clarified, it is inevita- 

 ble that confusion will continue. 



Source: Isolated from the lungs in cases 

 of lobar pneumonia. 



Habitat: Associated with pneumonia and 

 other inflammations of the respiratory 

 tract. 



2. Klebsiella ozaenae (Abel, 1893) 

 Bergey et al., 1925. {Bacillus mucosus 

 ozaenae Abel, Cent. f. Bakt., 13, 1893, 167; 

 Bacillus ozaenae Abel, ibid., 172; Bacterium 

 ozaenae Lehmann and Neumann, Bakt. 

 Diag., 1 Aufl., 2, 1896, 204; Bergey et al., 

 Manual, 2nd ed., 1925, 266.) 



o.zae'nae. L. fem.n. ozaena ozena; L. 

 fem.gen.n. ozaenae of ozena. 



Plump rods, 1.25 microns in width and of 

 variable length, occurring singly. Encap- 

 sulated. Non-motile. Gram-negative. 



Gelatin colonies: Small, white, convex, 

 slimy, translucent. 



Gelatin stab: Translucent, slimy surface 

 growth. Filiform growth in stab. No lique- 

 faction. 



Agar slant: Slimy, cream-like, spreading 

 growth. 



Broth: Turbid; gray ring and sediment. 



Litmus milk: Unchanged or slightly acid 

 but not coagulated; no gas. 



Potato : Creamy, spreading growth ; never 

 shows gas production. 



Indole not produced. 



Acetylmethylcarbinol not produced. 



Acid ma}- or may not be produced from 

 glucose; lactose is fermented weakly, if at 

 all (Lehmann and Neumann, Bakt. Diag., 

 4 Aufl., 2, 1907, 299). Acid and gas from 

 glucose, lactose, sucrose, maltose and 

 mannitol (Julianelle, Jour. Bact., 30, 1935, 

 536). 



Nitrites produced from nitrates (Julia- 

 nelle, ibid., 535). 



