Mycobacterium leprae
Scientific Classification
"Mycobacterium" means "waxy bacteria" and "leprae" means "scaly skin."
Kingdom: Bacteria
Phylum: Actinobacteria
Order: Actinomycetales
Suborder: Corynebacterineae
Family: Mycobacteriaceae
Genus: Mycobacterium
Species: M. leprae
It's easy to look at a listing of the scientific classification, but why does it belong to each of those groups? Here is a brief explanation...
Kingdom: Bacteria
This organism belong to the kingdom bacteria because it fits the typical characteristics of prokaryotic bacteria, which I have already listed in the page "what are bacteria."
Phylum: Actinobacteria
Actinobacteria is bacteria which is highly gram positive. This fits well because this organism is gram positive.
Order: Actinomycetales
This fits the organism well because it consists of gram positive organisms which can be difficult to culture, and often are pathogenic to humans, plants, or animals.
Suborder: Corynebacterineae
This fits because the basic characteristics of this order include gram-positive, rod-shaped bacteria that can be the cause of human diseases, particularly ones with infections of the lymph and skin.
Family: Mycobacteriaceae
This family has the characteristics of being known to cause serious diseases in mammals, aerobic and nonmotile, are acid-alcohol fast, gram positive, and lack an outer membrane.
Genus: Mycobacterium
The genus mycobacterium is known for having waxy components in it's cell wall, lacking an outer membrane, being non-motile, and acid-alcohol fast.
Species: M. leprae
The last, most specific group puts all of the above into one species, the M. leprae. The characteristics of this species include gram-positive, aerobic rod-shaped cells surrounded by waxy coating which cause serious disease in mammals.
As you can see based on this phylogenetic tree of life, there are 3 domains-bacteria, archea, and eukarya. Bacteria is the least closely related to the eukaryotic organisms, and is located to the left. This tree is based on molecular RNA data. Other phylogenetic trees based on other molecular data tend be very similar, with small differences placed in the earliest of the branching groups. As science and technology continue to grow, people are continuing to debate where everything fits in alignment with one another, as well as where the true root lies. Because of this and other aspects of genetics, some also can debate that maybe a phylogenetic tree does not serve the best representation of how the domains are connected.
The above is a tree of the bacteria alone, with the yellow organisms belonging to the archeabacteria. As you can see, Mycobacterium leprae is very closely associated with the the Mycobacterium tuberculosis.
There are 1500 genes which are common to both M. leprae and M. tuberculosis. Comparing the two suggests that both were derived from a common ancestor.