The rumen contents of red deer (Cervus elaphus) were used to isolate bacteria capable of fermenting glycerol. The biochemistry, physiology, morphology and phylogeny of one isolate were studied in detail. The isolate (DR3) was tentatively identified as a strain of the species Klebsiella planticola as based on phenotypic characterization. The data obtained from 16S rRNA sequence analysis showed that the deer rumen isolate DR3 was 99·7% similar to the type strain of Kl. planticola (DSM 3069T), thus confirming the results of the phenotypic characterization. During active cell growth, it was established that glycerol dissimilation by Kl. planticola DR3 led to the production of formate and ethanol at equimolar levels of 32 mmol l−1 and 30 mmol l−1, respectively. As a result of the data obtained, a closed carbon balance was constructed for Kl. planticola DR3. This finding represented the first report of the complete end-product profile for glycerol dissimilation by a strain of Kl. planticola isolated from cervine rumen contents.