Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “BACITRACIN”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 109 records · Page 6Linked to original sources

[Cloning of the genes controlling the biosynthesis of bacitracin in Bacillus licheniformis].

The DNA fragment from bacitracin-producing Bacillus licheniformis strain is cloned on pMX39 vector plasmid in Bacillus subtilis cells. Bacillus subtilis cells carrying the cloned fragment inhibit the growth of bacitracin-sensitive tester strain. The observed inhibition of growth is due to the production by Bacillus subtilis of bacteriocin substance that is identified as bacitracin by TLC-chromatography. In contrast to the data published earlier it is shown that Bacillus subtilis can in fact produce the small amounts of bacitracin. Introduction of the cloned Bacillus licheniformis DNA into Bacillus subtilis cells stimulates this bacitracin production. The restriction site map of the Bacillus licheniformis chromosomal region bearing the cloned fragment is constructed.

Bacillus↗

Cylinder plate assay for determining bacitracin in premix feeds and finished feeds: collaborative study.

A cylinder plate assay procedure was studied by 10 laboratories. For premix feeds, 3 samples of bacitracin methylene disalicylic acid and 3 samples of bacitracin zinc premixes covering the range of 10 to 50 g/lb were used. The repeatability standard deviation was 2.11, and the reproducibility standard deviation was 2.13. The average recovery of bacitracin was 101.5%. The method has been adopted official first action. For finished feeds, 6 samples of bacitracin methylene disalicylic acid and 6 samples of bacitracin zinc covering the range of 10 to 800 g/ton were used in the study. The procedure included a sample cleanup step using disposable reverse phase columns. This step appears to be the cause of the poor results reported by most collaborators. Continued study is needed to develop an acceptable method for finished feeds.

Animal Feed↗

High pressure liquid chromatographic determination of bacitracin in premix feeds and finished feeds: collaborative study.

A liquid chromatographic technique for the determination of bacitracin in finished feeds and premix feeds consists of an isocratic reverse phase, ion-suppressed technique. The chromatography can be completed in less than 25 min. In a collaborative study involving 9 laboratories and 3 samples of bacitracin methylene disalicylic acid and 3 samples of bacitracin zinc premixes covering the range of 10-50 g/lb, the repeatability standard deviation was 0.55, and the reproducibility standard deviation was 1.35. The average recovery of the bacitracin was 102.0%. The method has been adopted official first action for bacitracin in premix feeds.

Animal Feed↗

[Effect of auxotrophic mutations on the bacitracin production level in Bacillus licheniformis].

The bacitracin production levels in some auxotrophic mutants of a highly active strain 1001 and strain ATCC 10716 were studied. It was shown that auxotrophic mutations in the genomes of the above strains resulted in decreasing of bacitracin production. In double auxotrophic mutants the synthesis of bacitracin was sometimes at the level of the initial strain. It was found that various amino acids and bases added to the cultivation medium in concentrations of 1 to 10 mg/ml either increased or decreased the production of bacitracin. It is suggested that some amino acids may play the decisive role in the control of the bacitracin synthesis.

Amino Acids↗

[Method of determining bacitracin residues in animal husbandry food products].

Distribution of bacitracin in rabbits when given orally was studied. It was found that bacitracin was absorbed from the gastrointestinal tract, penetrated into the organs and tissues, was partially bound there and rapidly excreted with the urine and bile. The highest percentage of the antibiotic binding was registered in the bone marrow and organs of the lymphoid system. Since the binding of the antibiotic was selective (only in the organs of the lymphoid system) and its presence in the muscle tissue and subproducts (liver, kidneys, etc.) was in the trace amounts, they do not prevent the use of such products in food. Thermal treatment of such products eliminates the antibiotic activity which is also in favour of their use. Therefore, bacitracin may be widely used as a growth stimulator in cattle breeding. For detection of the bacitracin bound fraction in the organs, tissues and animal products it is recommended to use enzymatic hydrolysis of the biological substrates containing bacitracin with a 2 per cent pepsin solution prepared in phosphate buffer, pH 6.0-6.2.

Animals↗

Bacitracin Inhibits the Synthesis of Lipid-linked Saccharides and Glycoproteins in Plants.

The particulate enzyme fraction from mung bean (Phaseolus aureus) seedlings catalyzes the incorporation of mannose from GDP-[(14)C]mannose into mannosyl-phosphoryl-dolichol and of N-acetylglucosamine from UDP-[(3)H]N-acetylglucosamine into N-acetylglucosamine-pyrophosphoryl-polyisoprenol. Bacitracin inhibits the transfer of both of these sugars into the lipid-linked saccharides with 50% inhibition being observed at 5 mm bacitracin. This antibiotic did not inhibit the transfer of glucose from UDP-[(14)C]glucose into steryl glucosides or the incorporation of glucose into a cell wall glucan. Bacitracin also inhibited the in vivo incorporation of [(14)C]mannose into mannosyl-phosphoryl-dolichol and into glycoprotein by carrot (Daucus carota) slices. While bacitracin also inhibited the incorporation of lysine into proteins by these slices, protein synthesis was less sensitive than glycosylation. Thus at 2 mm bacitracin glycosylation was inhibited 92%, while protein synthesis was inhibited only 50%.

Journal Article↗

Effect of bacitracin on erythroid differentiation of MEL cells.

Bacitracin, an antibiotic widely utilized in clinical and veterinary use, was tested on murine erythroleukemia (MEL) cells. Tests were performed to evaluate the capacity of the drug to interfere with erythroid differentiation. Cells were exposed to a single treatment in S phase at sublethal doses of bacitracin. Two responses were found depending on the drug concentration. At higher concentrations (25 micrograms/ml and 250 ng/ml) a reduction in number of differentiating cells was observed but the kinetics of the process remained unchanged. At lower concentrations (from 2.5 ng/ml to 2.5 fg/ml) a dramatic alteration of the dynamic of differentiation was found. These two responses are related to different activities of the DNA repair mechanisms. Higher doses of bacitracin stimulate repair while lower concentrations are not able to active repair, as demonstrated by tests with hydroxyurea. The bacitracin-induced damage can be considered a stable genetic and/or epigenetic alteration, as demonstrated by the high frequency of mutant clones isolated from low-dose treated cells. The suitability of MEL cells system in evaluating genotoxicity of drugs for veterinary use is underlined.

Animals↗

Bacitracin: substantiation and elimination of contaminating proteolytic activity and use as an affinity chromatography ligand to purify a siderophore-degrading enzyme.

Bacitracin is a commercial general peptidase inhibitor that may be used to purify proteases. Significant protease contamination of a commercial bacitracin preparation was noted and four procedures were developed to overcome the contamination. Dialysis, gel-filtration chromatography, molecular weight cutoff filters, and heat inactivation were effective, resulting in the diminution or elimination of proteolysis while maintaining the inhibitory effect of bacitracin. Attachment of bacitracin to an affinity chromatography resin did not immobilize a siderophore-degrading enzyme, as has been noted with peptidases. It did, however, result in its partial purification from some of the contaminating proteins originally present.

Bacitracin↗

Systemic absorption of bacitracin after peritoneal lavage.

Nine patients underwent intraoperative peritoneal lavage with a solution containing 50,000 units of bacitracin in 200 ml of 0.9 per cent sodium chloride. The solution was removed by suction at 2 or 5 minutes, and venous blood samples were obtained at 15 minute intervals for 2 hours after lavage. Concentrations of bacitracin in serum were determined by agar diffusion assay. In the majority of patients, peak concentrations of bacitracin in serum occurred by 15 minutes post lavage. The mean peak serum concentration was 3.8 units/ml, which exceeds peak concentrations after intramuscular injection of 50,000 units. Due to potential nephrotoxicity, bacitracin should be used cautiously in peritoneal lavage solutions and should be abandoned in patients who have renal impairment in whom prolonged elevated serum concentrations could develop.

Absorption↗

Chemotherapy of Entamoeba histolytica: studies in vitro with bacitracin and its zinc salt.

Twenty-one Entamoeba histolytica isolates from a range of geographical locations and representing 3 different zymodemes were tested under xenic anaerobic conditions for their sensitivities to bacitracin and bactracin zinc. Isolates were over 13 times more sensitive to bacitracin zinc than to bacitracin. Our results indicate that bacitracin zinc may form the basis of an alternative non-toxic treatment of luminal amoebiasis.

Animals↗

Recovery of murine myelopoiesis after cytostatic reduction by Ara-C. Effect of bacitracin-induced changes in the intestinal microflora and influence of timing.

The influence of intestinal flora modulation by oral bacitracin on the recovery of myelopoiesis after Ara-C was studied in C3H/Law mice. Bacitracin resulted in a 3-5 log increase of Gram-negative bacteria and a 10-fold increase of the intestinal endotoxin concentration. Initiation of bacitracin before Ara-C stimulated the initial rebound increase of colony-forming units for granulocytes and macrophages (CFU-GM) from 23.2 +/- 1.3 to 28.4 +/- 1.4 x 10(3) per femur. Starting the bacitracin after Ara-C advanced the second phase of the rebound CFU-GM increase with 6 days. An important role in the recovery of myelopoiesis after cytostatic drugs in C3H/Law mice is suggested for the intestinal Gram-negative microflora, probably mediated by bacterial endotoxin.

Animals↗

Studies on the complex formed between bacitracin A and divalent cations.

Bacitracin A is a peptide antibiotic which forms stoichiometric complexes with divalent cations, including Ni2+ and Zn2+. In this paper it is shown that the metal-bacitracin complex contains a group which has a pKa near pH 5.5. Deprotonation of the group is concomitant with the aggregation and precipitation of the metal-bacitracin complex. Bacitracin A, in the absence of metals, does not contain any group which has a pKa in this range. It is postulated that this group is the N-terminal amino of isoleucine, which was previously postulated not to be directly involved in metal coordination based on proton release measurements. An attempt was made to demonstrate directly that the N-terminal amino group is not coordinated to the metal by examining the reactivity of this group with 2,4,6-trinitrobenzene sulfonate. It was clearly shown that bound metals protect the N-terminal amino group from reacting with this reagent. It is speculated that this metal-protection results from a combination of factors, including steric hindrance.

Bacitracin↗

Separation and isolation of the isomers of bacitracin by high-performance liquid chromatography and their relationship to microbial activity.

Bacitracin, a polypeptide antibiotic produced from strains of Bacillus licheniformis, is one of the most commonly used antibiotics in the world. Actually, the various products generally referred to as 'bacitracin' are mixtures of similar polypeptides which may differ by only one amino acid. The approved method of analysis for bacitracin is microbial. To correlate the microbiological method with an HPLC method, bacitracin was chromatographed using a YMC basic column with UV detection. Adequate separation of the isomers were obtained to scale up this procedure to preparative HPLC using a 250 x 21 mm YMC basic column. The various fractions were separated, isolated and examined for microbial activity. The chromatograms can accurately predict in minutes the microbiologically-determined potency which usually takes 16-24 h to develop. The chromatographic procedure also provides information on the amounts of isomers and degradation products present in the sample, whereas the microbiological assay only provides activities or potencies of the antibiotic. The reported HPLC method also possesses some advantages over some other published HPLC methods in terms of accuracy and time of analysis.

Bacitracin↗

Differential influence of bacitracin on plant proteolytic enzyme activities.

The effect of bacitracin on the activity of proteases extracted from pollen and sprouts of various plant species and compared to five commercially available proteases was studied. Bacitracin stimulates some pollen proteolytic enzyme activities, contrary to its inhibitory influence on proteases from the other sources. Proteases from maize pollen, inhibited by pepstatin and phenylmethylsulfonyl fluoride, immediately accelerate their activities after addition of bacitracin to the reaction mixture. The stimulating influence of peptide antibiotic on pollen proteases of some plants is unexpected and molecular mechanism of this phenomenon requires a further elucidation. The augmentation of allergenic response caused by pollen enzymes and drugs containing bacitracin is discussed.

Animals↗

Metal binding and structure-activity relationship of the metalloantibiotic peptide bacitracin.

Bacitracin is a widely used metallopeptide antibiotic produced by Bacillus subtilis and Bacillus licheniformis with a potent bactericidal activity directed primarily against Gram-positive organisms. This antibiotic requires a divalent metal ion such as Zn(2+) for its biological activity, and has been reported to bind several other transition metal ions, including Mn(2+), Co(2+), Ni(2+), and Cu(2+). Despite the widespread use of bacitracin since its discovery in the early 1940s, the structure-activity relationship of this drug has not been established and the coordination chemistry of its metal complexes was not fully determined until recently. This antibiotic has been suggested to influence cell functioning through more than one route. Since bacterial resistance against bacitracin is still rare despite several decades of widespread use, this antibiotic can serve as an ideal lead for the design of potent peptidyl antibiotics lacking bacterial resistance. In this review, the results of physical (including NMR, EPR, and EXAFS) and molecular biological studies regarding the synthesis and structure of bacitracin, the coordination chemistry of its metal derivatives, the mechanism of its antibiotic actions, its influence on membrane function, and its structure and function relationship are discussed.

Anti-Bacterial Agents↗

BcrC from Bacillus subtilis acts as an undecaprenyl pyrophosphate phosphatase in bacitracin resistance.

Overexpression of the BcrC(Bs) protein, formerly called YwoA, in Escherichia coli or in Bacillus subtilis allows these bacteria to stand higher concentrations of bacitracin. It was suggested that BcrC(Bs) was a membrane-spanning domain of an ATP binding cassette (ABC) transporter involved in bacitracin resistance. However, we hypothesized that this protein has an undecaprenyl pyrophosphate (UPP) phosphatase activity able to compete with bacitracin for UPP. We found that overexpression of a recombinant His6-BcrC(Bs) protein in E. coli (i) increased the resistance of the cells to bacitracin and (ii) increased UPP phosphatase activity in membrane preparations by 600-fold. We solubilized and prepared an electrophoretically pure protein exhibiting a strong UPP phosphatase activity. BcrC(Bs), which belongs to the type 2 phosphatidic acid phosphatase (PAP2) phosphatase superfamily (PF01569), differs totally from the already known BacA UPP phosphatase from E. coli, a member of the PF02673 family of the Protein family (Pfam) database. Thus, BcrC(Bs) and its orthologs form a new class of proteins within the PAP2 phosphatase superfamily, and likely all of them share a UPP phosphatase activity.

ATP-Binding Cassette Transporters↗

Effect of Lactobacillus acidophilus and zinc bacitracin as dietary additives for broiler chickens.

The influence of Lactobacillus acidophilus and zinc bacitracin alone, or in combination, on the growth of broiler chickens was monitored over a period of 8 weeks. 2. The maximum improvement in body weight over the controls was 10.8% with both additives in the diet but the use of bacitracin alone induced a 9.1% improvement. 3. Food conversion was reduced by zinc bacitracin alone but was improved by the use of L. acidophilus and bacitracin in combination. 4. The combination treatment increased abdominal fat deposition in the female chickens by 31%.

Adipose Tissue↗

Evaluation of zinc bacitracin capsules versus placebo for enteric eradication of vancomycin-resistant Enterococcus faecium.

Patients who are colonized with enteric vancomycin-resistant Enterococcus faecium (VREF) are a major reservoir for transmission of and infection with this organism. In a randomized, controlled study to assess the effectiveness of high-dose bacitracin in the eradication of enteric VREF, 12 patients who were colonized with VREF were randomized to receive placebo (n=6) or orally administered zinc bacitracin (n=6) for 10 days. Posttreatment perirectal or stool cultures indicated that after 3 weeks, VREF had been eradicated from the stool of only 2 (33%) of 6 patients in each group. Of the 8 remaining patients who were still VREF-positive at 3 weeks after treatment, 5 (62%) had later evidence of spontaneous enteric eradication at 8 weeks. Further testing of VREF isolates revealed that a significant number (n=22, 76%) were resistant to bacitracin and that patients may have been colonized with multiple different VREF strains. Although bacitracin was not effective in the enteric eradication of VREF, the high rates of spontaneous eradication suggest that other host and environmental factors are more important in achieving long-term suppression or elimination of VREF colonization.

Anti-Bacterial Agents↗