Bacillus subtilis Bacitracin

A subsequent patent, U.S. Patent 2,828,246 described a commercial process for bacitracin production. A 1,230 gallon portion of a medium containing 10% soybean oil meal, 2.50% starch and 0.50% calcium carbonate having a pH of 7.0 was inoculated with a culture of bacitracin-producing bacteria of the Bacillus subtilis group and the inoculated medium incubated for a period of 24 hours with aeration such that the superficial air velocity was 12.1. An assay of the nutrient medium following the fermentation revealed a yield of bacitracin amounting to 323 units/ml. This was more than twice the yields previously obtained. 

Bacitracin Bacillus subtilis Gram-positive bacteria Wall synthesis... 

Bacitracin is a mixture of polypeptide antibiotics produced by Bacillus subtilis. As with penicillin, it contains a thiazolidine nucleus attached through L-leucine to a peptide composed of both d- and L-amino acids. However, it does not contain a (3-lactam ring. Bacitracin prevents cell wall synthesis by binding to a lipid pyrophosphate carrier that transports cell wall precursors to the growing cell wall. 

Bacitracin is a linear-ring peptide antibiotic produced by Bacillus subtilis and Bacillus licheniformis. Commercial formulations of bacitracin comprise a mixture of many closely related compounds classified into bacitracin A, B, C, D, E, F, and G (5). The main components are bacitracin A, B, and B2, constituting 57%, 22%, and 13%, respectively, of the mixture, whereas bacitracin F constitutes less than 2%. Bacitracin F is actually a degradation product of bacitracin A that... 

Most biologically active natural peptides are linear, but bacitracin is a leading member of the so-called cyclic peptide type of antibiotics. The commercial material, extracted from Bacillus subtilis, is a mixture of several compounds in which bacitracin A predominates. It exerts its action by inhibiting peptidoglycan synthesis and membrane function. Bacitracin has been a useful antibiotic since the 1960s, but its systemic use results in a number of toxic side effects, including nephrotoxicity. One cannot be sure which components of the mixture are responsible for the toxicity, and separation of natural constituents is complex and difficult. For this reason, an efficient synthesis of bacitracin A would be useful. 

Bacitracin" is submitted as mixture of bacitracin A with other bacitracins. From culture of Bacillus subtilis and purification on ion-exchangers. 

Among the peptide antibiotics are gramicidin S (from Bacillus brevis) and bacitracin A (from Bacillus subtilis), which contain D-amino acids in addition to l-amino acids ... 

Bacitracin is a polypeptide produced by the growth of an organism of the licheniformis group of Bacillus subtilis. A white to pale buff hygroscopic powder. 

Finally, bacitracins are peptide antibiotics produced by Bacillus subtilis and B. licheniformis. Over 20 components are contained in the bacitracin complex medium, among which the major active components are bacitracin A and F (Fig. 3). They exhibit an inhibitory activity against Gram-positive bacteria and are among the most commonly used antibiotics as animal feed additives. 

Despite the apparent connections between formation of antibiotics and spores, it has become clear that antibiotic production is not obligatory for spore formation [192]. The most damaging evidence to the antibiotic-spore obligatory hypothesis is the existence of mutants which form no antibiotic but still sporulate. Such mutants have been found in the cases of bacitracin (Bacillus licheniformis), myco-bacillin (Bacillus subtilis), linear gramicidin (B. brevis), tyrocidine (B. brevis), gramicidin S (B. brevis), oxytetracycline (Streptomyces rimosus), streptomycin (S. griseus), methylenomycin A (Streptomyces coelicolor), and patulin (Penicillium urticae). 

Inhibitor 1781 Bacillus subtilis 1823 Bacillus thuringicnsis toxin 898 Bacitracin 1472... 

There are several antibiotics that affect Stage II reactions. Bacitracin, which is isolated from Bacillus subtilis, is active against many important Gm+ bacteria. However, its nephrotoxicity precludes its systemic administration. It has therefore been relegated almost exclusively to the treatment of superficial skin infections and occasionally the eye. The drug is generally used in ointment form, sometimes in combination with other antibiotics such as polymyxin and neomycin. 

The bacitracin zinc and polymyxin B sulfate ophthalmic ointment USP is a sterile antimicrobial ointment formulated for ophthalmic use. Bacitracin zinc is the zinc salt of bacitracin, a mixture of related cyclic polypeptides (mainly bacitracin A) produced by the growth of an organism of the lichenlformis group of Bacillus subtilis var Tracy. It has a potency of not less than 40 bacitracin units per milligram. Polymyxin B sulfate is the sulfate salt of... 

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. 

Bacitracin is also of historical interest, having been discovered in 1943 not long after the intensive and still ongoing research effort to find other antibiotics was mounted. Like penicillin, it remains a commercially available antibiotic. The heterocyclic fragment is relatively simple it is a thiazolidine derivative with attachment to a polypeptide. The fermentation with Bacillus subtilis actually produces a mixture of related compounds, the major one being bacitracin A with structure 3.35. 

Bacitracin. International generic name for a peptide antibiotic complex with broad activity against Grampositive pathogens, especially staphylococci, penicillin- and sulfonamide-resistant streptococci and some Gram-negative cocci and bacteria, B, is isolated from Bacillus subtilis and B. licheniformis. Commercial B. is a mixture with B. A as main component (70%). B. A has the following constitution ... 

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