- An antibacterial mixture obtained from peptone cultures of Bacillus brevis; bactericidal and bacteriostatic, and active against Gram-positive bacteria. It yields the crystalline antibacterial agents gramicidin and tyrocidin; the gramicidin component is a polypeptide containing l-tryptophan, d-leucine, d-valine, l-valine, l-alanine, glycine, and an aminoethanol; the tyrocidin component is a cyclopolypeptide containing tyrosine, ornithine, and several other amino acid s.
* * *ty·ro·thri·cin .tī-rə-'thrīs-ən n an antibiotic mixture that consists chiefly of tyrocidine and gramicidin, is obtained from a soil bacterium of the genus Bacillus (B. brevis), and is used in the topical treatment of infections esp. of the skin and mouth caused by gram-positive bacteria
* * *n.an antibiotic derived from the bacterium Bacillus brevis. It is used in combination with benzocaine, in the form of lozenges (Tyrozets), in the treatment of infections of the mouth and throat.
* * *ty·ro·thri·cin (ti″ro-thriґsin) an antibiotic substance isolated from the soil bacillus Bacillus brevis, consisting principally of two polypeptides, the major one being tyrocidine and the other gramicidin. It is effective against many gram-positive bacteria, and is applied topically in pyodermic, ocular, and other localized infections due to susceptible organisms.
Medical dictionary. 2011.