Kurthia

Kurthia, in addition to other coryneform genera being Cellulomonas, Arthrobacter, Brevibacterium and Corynebacterium, differs in a number of ways. To start, Kurthia has a very different taxonomical status in that it resides in the Firmicute phylum of the bacterial domain rather than in the Actinobacteria phylum like the other genera (Brands S.J. 1989-Present). In addition, the genus is also subsequently found in the Bacillales order and grouped in the Planococcaceae family (Krasilnikov 1949, Brands S.J.). Such a vast difference in taxonomical groupings, due to Kurthia’s totally different genome structure, gives the bacterium a number of different ecological and biological characteristics:

Biological Similarities to rest of coryneforms:

1) Aerobic

2) Non spore forming

3) Gram-positive

4) Catalse Positive

5) V-shaped Cells

Biological Differences to rest of coryneforms:

1) Motile by peritrichious flagellum

2) Low GC content e.g. 36.6-37.8% (Shaw, 1984)

3) Different cell wall composition e.g. only contains lysine and aspartic acid.

Figure 1.1: Shows the colony morphology of K. massiliensis after staining. Cells reside as cocci form in late stages of life. (Source: Roux, 2012).

Habitat

This is evident in Kurthia species such as K. zopfii & K. gibsonii which occur in the microflora or meats and animal waste (Bergeys, 1984; Davies A.R., 1998). Such an ecological position is rarely seen in other coryneforms, apart from Corynebacterium species such as C. diptheriae which can occur in the skin microflora of humans

Pathogenicity

Kurthia are primarily non-pathogenic. However, K. spp have been isolated from stool samples in patients suffering from diarrohea as well as a few cases of endocarditis (Bergeys, 1984; Hardy Diagnostics, 2014).