An isolate of Corynebacterium , then referred to as Strain 1170 T, was first found in August of 2009 from a 47 year old female. The female had been bitten by her dog in the forearm, hence the name Corynebacterium canis. When the genetic make-up of the organism was analyzed using 16S ribosomal RNA, the genetic divergence of the strain was found to be well above the 1.3% threshold. This enabled the strain to be classified as a novel species of Corynebacterium. It’s nearest phylogenetic relatives include, C. argentoratense, C. diphtheriae, C. freiburgense, C. pseudotuberculosis, and C. ulcerans.
C. canis cells are gram positive cells, some having typical club shaped rods, while others are more branched and filamentous. These filamentous rods are very unique to this species, as none of its nearest phylogenetic relatives have this characteristic. The peptidoglycan cell wall of C. canis consists of both mycolic acids and meso-diaminopimelic acid. This causes the cells to have a negative reactions when tested for partial acid-fasteness. The main straight chain of the saturated fatty acids were palmitic and stearic acids. Oleic acid was the predominant unsaturated fatty acid.
C. Canis is a facultative anaerobe with the ability to ferment most sugars. It has also been found to be catalase positive. It is the only medically relevant species of Corynebacterium expressing trypsin activity. Trypsin is an enzyme responsible for the cleavage of proteins, aiding in digestion of food. This would be an advantageous trait to have within the natural habitat of a dog’s mouth.
Citation: Funke G, Englert R, Frodl R, Bernard K, Stenger S.Corynebacterium canis sp. nov., isolated from a wound infection caused by a dog bite. Int J Syst Evol Microbiol 60(11):2544-2547 doi:10.1099/ijs.0.019927-0