[citation needed] In the 1980s, prior to the use of Bacillus subtilis for this purpose, P. megaterium was the main model organism among Gram-positive bacteria for intensive studies on biochemistry, sporulation, and bacteriophages.

Recently, its popularity has started increasing in the field of biotechnology for its recombinant protein-production capacity.

[3] P. megaterium has a complex plasmid content [9] as well as some phenotypic and phylogenetic similarities with pathogens B. anthracis[10] and B. cereus, although itself being relatively harmless.

In addition to being a common soil bacterium and an endophyte, it can be found in various foods (including honey and bee pollen,[11] in which most microorganisms do not grow) and on a variety of surfaces, including clinical specimens, leather, paper, stone etc.

[3] The species was described by de Bary in 1884, who called it Bacillus megaterium, but did not give an etymology.

The name P. megaterium is a nominative noun in apposition (see Rule 12 of IBCN[16]) and is formed from the Greek adjective mega, (μέγας , μεγάλη, μέγα) meaning "great",[17] and a second word of unclear etymology.