The important role of microorganisms as disease agents and in cycling nutrients in the environment ties the study of microbiology closely to both medicine and agriculture. Microbiology also impacts the areas of bioremediation, alternative fuels, and astrobiology, the study of possible life on other celestial bodies.

Modern biotechnology has its roots in applications of microbiology, supplying us with antibiotics, insulin, interferon, human growth hormone, and a host of other medical and research products previously available only in trace amounts.