Bacitracins other microorganisms

Products and Uses A chemical substance produced by microorganisms that has the ability to inhibit the grovvth of other microorganisms or destroy them. Synonyms are tyrothricin, bacitracin, polymxin, actinomycin, streptomycin, chloramphenicol, tetracycline. Certain antibiotics are used as food additives to inhibit the growth of bacteria and fungi. These are nisin, pimaricin, nystatin, tylosin. 

Bacitracin is a mixture of similar peptides produced by fermentation of the bacterium Bacillus subtilis. The A-type component predominates. Its mode of action is to inhibit both peptidoglycan biosynthesis at a late stage (probably at the dephosphorylation of the phospholipid carrier step) and disruptions of plasma membrane function. It is predominantly active against Gram-positive microorganisms, and parenteral use is limited to IM injection for infants with pneumonia and empyema caused by staphylococci resistant to other agents. It is rather neuro- and nephrotoxic and, therefore, is used in this manner with caution. Bacitracin also is widely employed topically to prevent infection in minor cuts, scrapes, and burns. 

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