The genus Corynebacterium belongs to a suprageneric group of actinomycetes that also includes the genera Mycobacterium, Nocardia and Rhodococcus. These gram-positive bacteria termed the CMN group, constitute a very heterogeneous group. Most of the species share particular characteristics, such as: (i) a specific cell wall organization, mainly characterized by the presence of a huge polymer complex composed of peptidoglycan, arabinogalactan and mycolic acids and (ii) high G+C content.
Compared with non-pathogenic environmental relatives such as C. efficiens and C. glutamicum, C. diphtheriae has 13 regions that are described as recently horizontally acquired DNA, including predicted iron-uptake systems, adhesins and fimbrial proteins. This suggests that the adoption of a pathogenic niche is a recent event for C. diphtheriae.
The most notable human pathogen of the genus Corynebacterium is exotoxin-producing C. diphtheria, the causative agent of the acute, communicable disease diphtheria.
C. jeikeium: the causative agent of a variety of severe nosocomial infections, most frequently associated with immunocompromised patients with malignancies, in-place medical devices, breaks in the skin barrier, and therapy with broad-spectrum antibiotics.
Genomes (comparative pathogenomics):
C. diphtheriae NCTC 13129, 2488635 bp, NC_002935
C. efficiens YS-314, 3147090 bp, NC_004369
C. glutamicum ATCC 13032, 3309401 bp, NC_003450
C. glutamicum ATCC 13032 (DSM 20300), 3282708 bp, NC_006958
C. glutamicum R, 3314179 bp, NC_009342
C. jeikeium K411, 2462499 bp, NC_007164
C. pseudotuberculosis FRC41, 2337913 bp, NC_014329
Ikeda M, Nakagawa S, 2003. The Corynebacterium glutamicum genome: features and impacts on biotechnological processes. Appl Microbiol Biotechnol 62(2-3):99-109.
Nishio Y, et al., 2003. Comparative complete genome sequence analysis of the amino acid replacements responsible for the thermostability of Corynebacterium efficiens. Genome Res 13(7):1572-1579.
Kalinowski J, et al., 2003. The complete Corynebacterium glutamicum ATCC 13032 genome sequence and its impact on the production of L-aspartate-derived amino acids and vitamins. J Biotechnol 104(1-3):5-25.
Cerdeno-Tarraga AM, et al., 2003. The complete genome sequence and analysis of Corynebacterium diphtheriae NCTC13129. Nucleic Acids Res 31(22):6516-6523.
Tauch A, et al., 2005. Complete genome sequence and analysis of the multiresistant nosocomial pathogen Corynebacterium jeikeium K411, a lipid-requiring bacterium of the human skin flora. J Bacteriol 187(13):4671-4682.
Yukawa H, et al., 2007. Comparative analysis of the Corynebacterium glutamicum group and complete genome sequence of strain R. Microbiology 153(4):1042-1058.
Major virulence factors in Corynebacterium:
SpaA-, SpaD- and SpaH-type pili
Location of virulence-associated genes in C. diphtheriae: