It is a mixture of related cyclic peptides produced by Bacillus licheniformis bacteria, that was first isolated from the variety "Tracy I" (ATCC 10716) in 1945.

[7] As bacitracin zinc salt, in combination with other topical antibiotics (usually polymyxin B and neomycin) as an ointment ("triple antibiotic ointment," with the brand name Neosporin), it is used for topical treatment of a variety of localized skin and eye infections, as well as for the prevention of wound infections.

[11] Its name derives from the fact that a compound produced by a microbe in young Margaret Tracy's (1936–1994)[12] leg injury showed antibacterial activity.

When cell-free filtrates of broth cultures of this bacillus proved to possess strong antibiotic activity and to be non-toxic, further study seemed warranted.

[14] Bacitracin is synthesised via nonribosomal peptide synthetases (NRPSs), which means that ribosomes are not directly involved in its synthesis.