<unk>  is a genus of Actinobacteria, given its own family, the Mycobacteriaceae.  The genus includes pathogens known to cause serious diseases in mammals, including tuberculosis and leprosy. The Latin prefix "myco—" means both fungus and wax; its use here relates to the "waxy" compounds in the cell wall.
Mycobacterium
Mycoplasma
Corynebacterium
Cryptococcus neoformans
Peptococcus
Nontuberculous mycobacteria
Candida 
Bacillus anthracis