Chloramphenicol bacitracin

Some other antibiotics commonly used in animal production such as the bacitracins, bambermycins and virginiamycins as well as the streptomycins are poorly absorbed from the intestinal tract and residues usually do not occur from feeding. Chloramphenicol is used illegally in the United States in many species it is used legally in Europe, Canada and other parts of the world. 

Rx with chloramphenicol (Chloromycetin/HC suspension—ophthalmic) with neomycin and polymyxin B (Cortisporin Otic, Drotic, Otocort—otic) with neomycin, polymyxin B, and bacitracin (Cortisporin Ointment, Neotricin HC—ophthalmic) with oxytetracycline (Terra-Cortril—ophthalmic) with urea (Carmol HC)... 

Various antibiotics bacitracin chloramphenicol colistimethate sodium fosfomycin tromethamine fusidic acid metronidazole polymyxin B sulfate rifabutin sodium fusidate... 

Polyoxyethylene stearates are unstable in hot alkaline solutions owing to hydrolysis, and will also saponify with strong acids or bases. Discoloration or precipitation can occur with salicylates, phenolic substances, iodine salts, and salts of bismuth, silver, and tannins.Complex formation with preservatives may also occur. The antimicrobial activity of some materials such as bacitracin, chloramphenicol, phenoxymethylpenicillin, sodium penicillin, and tetracycline may be reduced in the presence of polyoxyethylene stearate concentrations greater than 5% w/w. ... 

After the Second World War, the effort continued to find other novel antibiotic structures. This led to the discovery of the peptide antibiotics (e.g. bacitracin (1945)), chloramphenicol (Fig. 10.72) (1947), the tetracycline antibiotics (e.g. chlortetracycline (Fig. 10.71) (1948)), the macrolide antibiotics (e.g. erythromycin (Fig. 10.73) (1952)), the cyclic peptide antibiotics (e.g. cycloserine (1955)), and in 1955 the first example of a second major group of (3-lactam antibiotics, cephalosporin C (Fig. 10.41). 

Chloramphenicol eye drops should be used to prevent infection. A number of different antibiotics were used in different centres by physicians managing Iranian chemical warfare casualties. These included chloramphenicol, tetracycline, oxytetracycline, bacitracin and polymyxin B. No conclusions regarding the most effective drug could be drawn. There seems little reason to abandon the use of chloramphenical eye drops. 

Bacitracin was found to be synergistic in combination with penicillin, streptomycin, or neomycin, and could, in certain limited circumstances, be antagonized by tetracycline or chloramphenicol ". ... 

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. 

Aminosalicyclic acid, bacitracin, blood plasma, blood serum, methicillin salts, culture media, dextran, enzymes, gamma-globulin, hormones, streptomycin, iron dextran, lysine, casein hydrolysate, penicillin, serum hydrolysate, penicillin, serum hydrolysate, tetracycline vitamins, oleandomycin, chloramphenicol succinate salts... 

Hydrocortisone, prednisone, fludrotisone, triamcinolone, dexamethasone, betamethasone Penicillins, cephalosporins, vancomycin, bacitracin, polymycins, tetracyclines, chloramphenicol, erythromycin, streptomycin Quinacrine, chloroquine, quinine Nystatin, gentamicin, miconazole, tolnaftate, undecyclic acid and its salts Vidarabine, acyclovir, ribarivin, amantadine hydrochloride, iododeoxyuridine, dideoxyur-idine, interferons... 

The interaction between a number of antibiotics (oxytetracycline, tetracycline, tobramycin, clindamycin, cefamandole, bacitracin and chloramphenicol) and surgical metallic materials (316L stainless steel, Co-Cr and commercially pure Ti) has shown that only oxytetracycline exerts an effect on the electrochemical response. For all the materials this antibiotic shifted the corrosion potential of abraded surfaces in the noble direction, as seen in Figure 9.8. 

Suppression by excess nutrients has been found in the biosynthesis of polyketides (D 3.3), of gibberellins (D 6.3), of certain antibiotics, e.g., streptomycin (D 1.3), neomycin C (D 1.3), actinomycins (D 8.4.1), chloramphenicol (D 8.2), bacitracin A (D 23), enniatin B (D 23), cephalosporins (D 23.3), and penicillins (D 23.3), of alkaloids, e.g., benzodiazepines (D 8.4.2), and ergolines (D 21.2) etc. Usually the suppression of secondary product formation is accompanied by the suppression of other characteristics of cell specialization (such as conidiospore formation in Peni-cillium cyclopium), indicating a general influence of nutrient supply on cell specialization. 

Curing of plasmids pRGOl, pRG02 and pRG05 from the respective strains had no effect on their capacity to synthesize bacteriocin, or to ferment 21 carbohydrates, as well as on their resistance to 21 antibiotics, including ampicillin, bacitracin, cephalotin, chloramphenicol, cloxacillin, erythromycin, fusidic acid, gentamycin, kanamycin, lyncomycin, metycillin, nalidixic acid, neomycin, novobiocin, oxacycline, penicillin, rifampicin, streptomycin, tetracycline, trimethoprim, and vancomycin. 

Figure 7.38 (a) and (b) The effect of non-ionic detergents on the activity of antibiotics as shown by the effect of (a) polyoxyethylene lauryl ether (CMC 0.011%) on penicillin, tetracycline, chloramphenicol, and bacitracin in concentrations ranging from 0.005 to 5.0 %, and (b) the effect of five different non-ionics on the activity of chloramphenicol (50 mg%). The critical micellar concentrations of the detergents are shown [172]. 

In the introduction the idea was put forward that antibiotics could be used as tools to assist in the elucidation of anabolic reactions. As each stage in amino acid assimilation has been uncovered in the course of these studies, the action of a number of antibiotics has been tested on that stage. The antibiotics used have been tyrocidin, penicillin, aureomycin, chloramphenicol (chloromycetin), terramycin, neomycin, streptomycin, bacitracin, and polymjrxin. With the exceptions of streptomycin and polymyxin, significant inhibitions of some stage or other in amino acid assimilation have been observed for all these antibiotics. These points of interference are summarized in Table XVI. 

Other antibiotics were quick to appear. Streptomycin was next, an antibiotic that was particularly effective against the causative organism of tuberculosis. The search was now on. Antibiotic prospectors combed the earth for organisms that produced different and more useful antibiotics. The list of these antibiotics is long today and includes such important antibiotics as chloramphenicol, the tetracyclines, bacitracin, erythromycin, novobiocin, nystatin, kanamycin, and many others. 

Cells of strain 10716 cultured in environments containing less than 6 X 10 M Mn+2 are unable to synthesize detectable quantities of bacitracin (Weinberg and Tonnis, 1966). When 2 X 10" M Mn+ is supplied to such cultures during the maximum stationary phase, the peptide appears in detectable concentrations in culture supernatants within four hr. However, if a quantity of chloramphenicol sufficient to suppress protein synthesis but not to kill vegetative cells is added either simultaneously or within two hr following the addition of Mn+, bacitracin is not formed. Apparently, in cells deprived of the metalhc ion, synthesis of either amino acid racemases or peptide assembly enzymes is suppressed (Weinberg and Tonnis, 1966). 

Inhibitors of protein synthesis as chloramphenicol (Bernlohr and Novelli, 1963 Cornell and Snoke, 1964), puromycin, and tetracycline (Cornell and Snore, 1964) do not suppress the formation of bacitracin by either whole cells or protoplasts that had been cultured in or derived from Mn+ -sufficient environments. The quantity of antibiotic produced by subcellular extracts is reduced by the presence of ribonuclease (RNase) but not as profoundly as can be generally observed in a system of protein biosynthesis deoxyribonuclease (DNase) has no effect on bacitracin yield (Shimura et al., 1964). In contrast, the ability of cell free extracts to produce the antibiotic is completely destroyed by detergents as, for example, sodium deoxycholate and sodium la urylsulf ate apparently, intact lipoprotein membranes are essential for the biosynthetic process (Shimura etaL, 1964). 

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