Lütticken R, Korth H, Pulverer G
Zentralbl Bakteriol Orig A. 1979 Sep;244(4):470-3.
Altogether 268 strains of Klebsiella were investigated with respect to their ability to ferment dulcitol and to produce indole, gelatinase, and brown pigment on a medium containing gluconate and ferric citrate. In addition the capacity of the strains to use m-hydroxybenzoic acid as sole source of carbon and energy was tested. Of the 83 indole-positive Klebsiella strains 72 (87%) were able to grow on the m-hydroxybenzoic acid medium, whereas only 2 (1%) of the indole-negative strains did so. Late liquefaction of gelatin occurred in 66 (80%) of the indole-positive strains. The ability of the indole-positive Klebsiella strains to use m-hydroxybenzoic acid as sole carbon source supports the view that these strains should be grouped in a separate taxon, which may be named Klebsiella oxytoca; it also provides a simple additional test for the identification of these strains.