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A new antifungal antibiotic named acmycin was isolated from a soil streptomycete. Detailed comparative taxonomic studies showed that the organism differed from three related species of streptomycetes. The organism was referred to asStreptomyces sp. AC2. The isolated antibiotic appears to be of polyene nature.  相似文献   

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Fredericamycin A (FM A), produced by a strain of Streptomyces griseus, represents a new structural class of antitumor antibiotics containing a spiro ring system. Studies on the producer organism showed that glucose in the fermentation medium is not utilized until late in the growth stage, just prior to synthesis of FM A. [14C]Glucose tracer experiments demonstrated that glucose is incorporated into FM A by catabolism to acetate. Biosynthetic enrichment of FM A with single- and double-labeled [13C]acetate showed that the entire carbon skeleton of the spiro ring system is derived from acetate. L-Methionine was shown to provide the only nonskeletal carbon in FM A, the methoxy carbon at position C-6. The direction of the polyketide chain and the position of the carbon lost during biosynthesis were established by using stable isotope experiments. A general model for FM A biosynthesis is proposed, and a possible scheme for the formation of the spiro carbon center is presented.  相似文献   

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Summary A new antibiotic, gluconimycin, was isolated from Streptomyces AS 9. The systematic position of the organism is discussed. Gluconimycin has a polypeptide nature. It contains iron and gluconic acid in its molecule. Thus it has been classified as a member of sideromycins. Gluconimycin is considered from the fast moving type when chromatographed by butanolacetic acid-water. The antibiotic is active against Gram+ve, Gram-ve bacteria and some fungi. The antibiotic exerts high toxicity when injected in mice.  相似文献   

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Nocamycin is produced by Nocardiopsis syringae. It is recovered from the culture fluid by extraction with chloroform. The molecular weight of the crystalline antibiotic is 503, its melting point is 147--149 degrees, [alpha]20 degrees D = --50 degrees (c. 0.21, chloroform), lambdamax235 and 348 nm(E1%sm= = 150 and 420), the summation formula is C26 H33NO9, the biological activity is 100000 Units/mg with respect to Bacillus mycoides. Nocamycin forms salts with alkalies soluble in water. On hydrolysis with an alkali it forms carbonic acid having no ester bond (IP spectrum) and methoxylic group present in the antibiotic molecule. Nocamycin is a new natural substance.  相似文献   

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Violamycin, a new red-pigment antibiotic   总被引:1,自引:0,他引:1  
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Cyanein,a new antibiotic fromPenicillium cyaneum   总被引:1,自引:1,他引:0  
Описываются выделение и некоторые особенности нового аптибиотика цианспина, полученного из Penicilliu, cyaneum. Цианеин—это белое кристаллическое вещество, пеитральпото характера, с точкой плавления 199,8–201,8°C (a)D 2 3 = + 82,7°. Он очснь слабо рас. творяется в воде, бензинеив петрольэ?ире, лучшс в этиловом спирте, ацетоне, поропилентликолс, п-бутаполс, этилацетате ив диэтилэ?ире. Циансин э??сктивен против Candida albicans и других грибков, не деиствует на исследовавшихся простейших и бактерии. Он заметно угнетаст размножение клеток HeLa, и его ID50 для этих клеток составляет 0,01 μг/мл  相似文献   

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The review is concerned with the outlooks for the use of levorin, a membrane active and channel forming polyene antibiotic, and its alkyl derivatives in muscle activity. In complex with cholesterol and ergosterol, the aromatic heptaene antibiotic levorin forms structural ionic channels of the molecular size in the lipid and cell membranes. Levorin increases the membrane permeability for monosucrose and other neutral molecules as follows: H2O > urea > acetamide > glycerine > ribose > arabinose > glucose > saccharose. As a channel forming compound, levorin is able to induce in the cell membranes of the muscle fibres formation of additional channels permeable for the cations and to increase the flow of the energy dependent substrates to the cells and the outburst of the metabolites from them during intensive muscle activity. Levorin several times decreases the surface tension of aqueous solutions. In some models of experimental animals levorin promoted an increase of the blood fluidity and accelerated the blood stream in the blood vessels both in rest and in muscle activity. Physical load in a high power zone increases the intensity of lipid peroxidation that results in fatigue and lower physical efficiency. Possible prevention of an increase of the rate of free radical reactions by levorin and its alkyl derivatives providing higher antioxidant protection is discussed.  相似文献   

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Mutants possessing 3 times higher activity as compared to the initial culture were obtained as a result of selection of active variants of Act. rubiginosonelvolus, a new organism producing rubomycin against the background of variation induced by N-methyl-N1-nitro-N-nitrozoguinidine, diethylsulphate and their combinations. Further selection among the mutants stable to 6-mercaptopurine and riboflavine resulted in obtaining an active culture No. 3912 at least 7 times more active with respect to rubomycin production than the initial soil culture.  相似文献   

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An antibiotic designated Ass was isolated from a soil streptomycete -which showed wide antibacterial activity. The antibiotic was extracted and purified into a yellow powder. Its physico-chemical and antimicrobial properties indicated that it is a novel peptide antibiotic.  相似文献   

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Acmycin, a new polyene antibiotic, was fungistatic at low and fungicidal at high concentrations. It produced malformations in conidia of Helminthosporium oryzae and Curvularia lunata and caused leakage of yeast cells. Acmycin was fairly nontoxic to germinating seeds. The intravenous LD50 was 300-400 and intraperitoneal maximum tolerated dose 100-500 mg/kg body mass of mice.  相似文献   

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Coprinol, a new antibacterial cuparane, was isolated from fermentations of a Coprinus sp. Its biological activities were investigated and its structure was elucidated by spectroscopic methods. The new antibiotic exhibited activitiy against multidrug-resistant Gram-positive bacteria in vitro. Two derivatives were synthesized and their activities compared to the parent compound.  相似文献   

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Spirillospora strain 719 produces several antibiotics. On solid and liquid media, a deep red pigment is formed and diffuses throughout the culture. It was extracted with methanol from the mycelium cake and from the fermentation broth after precipitation at pH 2 and purified using TLC and HPLC. Its u.v. absorption spectrum and its physicochemical characteristics place this antibiotic in the 3.3.2.2.8 of the Berdy et al. classification. In most respects, it resembles proteinaceous pigment from Spirillospora 1655 and 1309-b that was studied and named spirillomycin. However, HP17 differs from spirillomycin principally in molecular weight and chemical nature.  相似文献   

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