TAXONOMY: Bacteria -> Terrabacteria group -> Actinobacteria -> Actinobacteria -> Corynebacteriales -> Corynebacteriaceae -> Corynebacterium
'Corynebacterium' is a genus of Gram- positive, aerobic, rod-shaped bacteria. They are widely distributed in nature and are mostly innocuous. Some are useful in industrial settings such as C. glutamicum. Others can cause human disease, including most notably diphtheria, which is caused by Corynebacterium diphtheriae C. diphtheriae. Straight to slightly curved rods with tapered ends. Rods are usually short or of medium length. Club-shaped forms may be observed; sometimes ellipsoidal, ovoid or rarely, “whip handles” (see below, Corynebacterium matruchotii) or thinner rods with bulges (see below, Corynebacterium sundsvallense) observed. Snapping division produces angular and palisade arrangements of cells. Gram-stain-positive; some cells stain unevenly. Metachromatic (synonym being polyphosphate) granules may be observed for some species. Not-acid-fast (Ziehl–Neelsen stain), and no species has aerial mycelium. Nonsporeforming. All species are nonmotile. All species are catalase positive. All species are oxidase negative except for Corynebacterium bovis, Corynebacterium aurimucosum, Corynebacterium doosanense, and Corynebacterium maris (below). Many species are facultatively anaerobic and some are aerobic. Chemoorganotrophs. Some species are lipophilic. Many species produce acid from glucose and some other sugars in peptone media. Several species alkalinize citrate as sole carbon sources, but most do not.
DNA G+C content (mol%): 46–74.
A study of 197 middle-aged patients with Parkinson disease and 115 age-matched controls found that the risk of Parkinson disease was increased in carriers of the G allele of rs356219 SNP on chromosome 4 when combined with the presence of Corynebacterium in the gut.
Type species: Corynebacterium diphtheriae
This genus contains microbial species that can reside in the human gastrointestinal tract. [PMC 4262072]