Abstract: The present invention relates to compounds having antibiotic activity which are obtained from body fluids of mollusks, namely of certain West-African snails, to therapeutic drugs comprising these compounds, and to the use thereof for the preparation of a therapeutic drug for controlling infectious pathogens in humans and animals.

Abstract: The ability to convert carminomycin to daunorubicin can be conferred on a host by transforming the host with a recombinant vector comprising a DNA having the configuration of restriction sites shown in FIGS. 2, 3 & 4 and nucleotide sequence shown in FIG. 3 of the accompanying drawings or a restriction fragment derived therefrom containing a gene coding for carminomycin 4-O-methyltransferase.

Abstract: New antibiotics, unphenelfamycin and phenelfamycins A-D, are produced by microorganisms belonging to the genus Streptomyces. The antibiotics have antibacterial activity against gram-positive and gram-negative anaerobic organisms and are effective in improving the feed efficiency and growth rate of livestock, including poultry.

Abstract: The fermentation of a substrate selected among erythronolide B, erythronolide A and erythronolide A oxime with a novel mutant, Streptomyces antibioticus ATCC 31771, obtained from an industrial stock for the production of oleandomycin, said novel mutant being incapable of producing the same oleandomycin, permits novel macrolide antibiotics to be produced, having not only an activity range like that of erythromycin, but characterized by a greater stability in acidic environment, whereby for the administration of the antibiotic it is no longer necessary to have recourse to esters and/or salts highly toxic for the organism.

Abstract: From the fermentation carried, out with mutants blocked in the synthesis respectively of erythromycin and of oleandomycin, namely Streptomyces erythreus ATCC 31772 and Streptomyces antibioticus ATCC 31771, using as the substrate a derivative of erythronolide A, namely (8S)-B-fluoroerythronolide A, a derivative of erythronolide B, namely (8S)-B-fluoroerythronolide B, or a derivative of 3-O-mycarosyl-erythronolide B, namely 3-O-mycarosyl-(8S)-fluoroerythronolide B, the corresponding (8S)-8-fluoro derivatives of the erythromycins A,B, C and D, as well as 3-O-oleandrosyl-5-desosaminyl-(8S)-8-fluoroerythronolide A and 3-O-oleandrosyl-5-O-desosaminyl-(8S)-8-fluoroerythronolide B, all belonging to the class of the marcolide antibiotics are obtained.

Abstract: New anthracycline glycosides designated MA 144-G1, -G2, -L, -S1, -N1, -U1 and -Y which inhibit the growth of gram-positive bacteria and mammalian tumors are produced by fermentation of certain species of Streptomyces and by the chemical or enzymatic conversion of certain anthracycline glycosides. New microbiological and chemical processes are also provided for preparation of the anthracycline glycosides MA 144-S2 and -U2 which have been found to be identical with the previously reported anthracyclines, marcellomycin and musettamycin.

Abstract: New antitumor agents designated MA 144-M.sub.1 and MA 144-M.sub.2, which are anthracycline glycosides and inhibit the growth of gram-positive bacteria, e.g. Staphyococcus aureus, Bacillus subtilis and Sarcina lutea, and inhibit the growth of animal tumors such as leukemia L 1210, P 388 and sarcoma 180 are produced by fermentation of MA 144-producing strains of streptomyces and by the chemical or enzymatic conversion of aclacinomycin A or cinerubin A.

Abstract: New anthracycline glycosides designated MA 144-G1, -G2, -L,-S1, -N1, -U1 and -Y which inhibit the growth of gram-positive bacteria and mammalian tumors are produced by fermentation of certain species of Streptomyces and by the chemical or enzymatic conversion of certain anthracycline glycosides. New microbiological and chemical processes are also provided for preparation of the anthracycline glycosides MA 144-S2 and -U2 which have been found to be identical with the previously reported anthracyclines, marcellomycin and musettamycin.

Abstract: New antitumor agents designated MA 144-M.sub.1 and MA 144-M.sub.2, which are anthracycyline glycosides and inhibit the growth of gram-positive bacteria, e.g. Staphyococcus aureus, Bacillus subtilis and Sarcina lutea, and inhibit the growth of animal tumors such as leukemia L 1210, P 388 and sarcoma 180 are produced by fermentation of MA 144-producing strains of streptomyces and by the chemical or enzymatic conversion of aclacinomycin A or cinerubin A.

Abstract: New antitumor agents designated rhodirubin A and B, which are anthracycline glycosides and inhibit the growth of gram-positive bacteria and mammalian tumors, are produced by fermentation of rhodirubin-producing strains of Streptomyces, e.g. Streptomyces sp. ME 505-HEI (ATCC 31273).