[Increase in eremomycin production by regeneration and UV-irradiation of Amycolatopsis orientalis subsp. eremomycini protoplasts]. / Uvelichenie produktsii éremomitsina v rezul'tate regeneratsii i UF-oblucheniia protoplastov Amycolatopsis orientalis subsp. eremomycini.

Protoplast regeneration of Amycolatopsis orientalis subsp. eremomycini producing eremomycin leads to the change of cultural and morphological properties as well as synthesis of secondary metabolites. Formation of plus-variants with enchanced antibiotic production was promoted by UV-irradiation of protoplasts. These plus-variants can be successfully used for repeating protoplasting--UV-irradiation of protoplasts with further increasing of the strain productivity. Finally activity of the initial A. orientalis culture was increased 7-8 times. Proposed method is recommended for the improvement of actinomycetes strains producing antibiotics especially in the case of cultures with poor sporulation.

[Actinoplanes brasiliensis INA 3802--a producer of peptide antibiotics]. / Actinoplanes brasiliensis INA 3802--produtsent peptidnykh antibiotikov.

In the screening programme for new antibiotics an actinomycete culture designated as 3802 was isolated from a soil sample. The culture produced a complex of peptide antibiotics belonging to the group of lantibiotics. The antibiotic complex included gardimycin (actagardin) and new antibiotics of the same group. By the taxonomic properties strain 3802 was classified as Actinoplanes brasiliensis not previously known to produce gardimycin. Conditions of the antibiotic complex biosynthesis by strain 3802, the isolation methods and biological properties were studied.

[Isolation and identification of antibiotics produced by Actinoplanes brasiliensis INA 3802]. / Vydelenie i identifikatsiia antibiotikov, produtsiruemykh shtammom Actinoplanes brasiliensis INA 3802.

In the screening programme for new antibiotics produced by Actinoplanes brasiliensis an antibiotic complex A-3802 was isolated and studied in detail. It had a marked therapeutic effect in the treatment of staphylococcal sepsis in albino mice and was low toxic. Two components of the complex i.e. A-3802-IV-3 and A-3802-IV-4 were identified with the lantibiotics actagardin and its diamide disulfoxide. Antibiotics A-3802-V-4 and A-3802-VI-7 were shown to be new antibiotics of the same group.

[A novel antibiotic of the aureolic acid group. Isolation, physicochemical and biological properties, identification]. / Novyi antibiotik iz gruppy aureolovoi kisloty. Vydelenie, fiziko-khimicheskie i biologicheskie svoistva, identifikatsiia.

An antibiotic complex was extracted from the culture fluid of Streptomyces phaeofaciens, strain 51. By the physicochemical properties it was referred to the group of aureolic acid. The complex was separated to chromatographically pure components by column chromatography. The main component was designated as antibiotic 51-I. Its physicochemical and biological properties were studied. Comparison of the data on the study of antibiotic 51-I with the respective characteristics of the described antibiotics of the group of aureolic acid suggested that antibiotic 51-I is a new representative of this group.

[Streptomyces phaeofaciens, strain 51--producer of a novel antibiotic of the aureolic acid group]. / Streptomyces phaeofaciens, shtamm 51--produtsent novogo antibiotika gruppy aureolovoi kisloty.

An actinomycete strain 51 isolated from a soil sample collected in the Gobi Desert (Mongolia) was shown to produce a novel antibiotic of the group of aureolic acid. By the morphological, chemotaxonomic, cultural and physiological properties strain 51 was identified as belonging to Streptomyces phaeofaciens. The strain inhibited the growth of gram-positive bacteria and was inactive against gram-negative microbes and fungi. During natural variation strain 51 segregated into variants of 3 types. The variants differing from those of the main type possessed lower antibiotic activity. It was not observed earlier that S. phaeofaciens strains produced antibiotics of the group of aureolic acid.

[Albofungin formation by a strain isolated as a result of fusion of protoplasts of organisms producing aminoglycoside antibiotics]. / Obrazovanie al'bofungina shtammon, poluchennym v rezul'tate sliianiia protoplastov produtsentov aminoglikozidnykh antibiotikov.

Strain 344 synthesizing an antibiotic complex was isolated after fusion of the protoplasts of Streptomyces monomycini producing monomycin and Streptomyces kanamyceticus producing kanamycin. The major component of the complex was identified with albofungin and the minor one was suggested to be chloralbofungin. In the cultures of strain 344 variants forming monomycin were detected. After regeneration of the protoplasts of the parent strains there were isolated no stable clones synthesizing antibiotics differing from monomycin and kanamycin.

[Eremomycin--a new antibiotic of the polycyclic glycopeptide group]. / Eremomitsin--novyi antibiotik gruppy politsiklicheskikh glikopeptidov.

Eremomycin is a novel antibacterial antibiotic. It was isolated at the Institute of New Antibiotics, the USSR Academy of Medical Sciences from the culture fluid of actinomycete INA-238. By its physico-chemical and biological properties the antibiotic was classified as belonging to the group of polycyclic glycopeptides. Chemical structure of eremomycin was asserted and it was shown to be a new representative of the group close by its structure to vancomycin and differing from it by the carbohydrate composition and structure of tri-phenoxytriaminotricarboxylic acid. By its anti-bacterial spectrum eremomycin was found to be close to ristomycin and vancomycin. Still, its activity was 2-10 times higher. The antibiotic was several times less toxic than vancomycin. Unlike vancomycin and ristomycin, the novel antibiotic induced no tissue necrosis after its intramuscular administration. The chemotherapeutic indices of eremomycin in treatment of staphylococcal and streptococcal sepsis in albino mice exceeded 10 times those of vancomycin. At present eremomycin is under clinical trials.

[Eremomycin--a new antibiotic from the cyclic glycopeptide group]. / Eremomitsin--novyi antibiotik iz gruppy tsiklicheskikh glikopeptidov.

Eremomycin, a novel antibiotic belonging to the group of cyclic glycopeptides is produced by an actinomycete designated INA-238. Biosynthesis, isolation, physico-chemical and biological properties of the antibiotic are described. Eremomycin is shown to be close to vancomycin. However, by its chromatographic and electrophoretic mobility, presence of chlorine in the antibiotic molecule and optic characteristics eremomycin differs from vancomycin. Eremomycin is less toxic than vancomycin whereas its chemotherapeutic activity in treatment of infections caused by gram-positive organisms is higher.

[New antitumor antibiotics 5590 and 2928]. / Novye protivoopukholevye antibiotiki 5590 i 2928.

Antibiotics with an in vivo antiblastomic activity were isolated from the actinomycetous culture 5590 and 2928. The antibiotics were prepared in the crystalline form. The conditions for the biosynthesis of the antibiotics, their physicochemical constants and UV and IR spectra were determined. The acid hydrolysates of the antibiotics were studied. The antibiotics contained the same chromophore and different sets of amino acids. Antibiotics 5590 and 2928 were classified as peptides containing the chromophore group.

Yeast mutants with distorted cell membranes as a detection system for antitumor antibiotics.

Yeast mutants with distorted cell membranes, which are selectively inhibited by anticancer antibiotics and are not affected by antibacterial antibiotics, could be of considerable interest as test organisms. They could be used for the isolation of active antitumor substances from complex mixtures of natural compounds.

[New species of Actinomadura coeruleoviolacea sp. nov. and its antagonistic properties]. / Novyi vid Actinomadura coeruleoviolacea sp. nov. i ego antagonisticheskie svoistva

Eight strains of actinomycetes isolated from soil samples were described as representatives of Actinomadura coeruleoviolacea sp.nov. The species was characterized by straight and sometimes branching short chains of spores, smooth spores, blue aerial mycellium and violet soluble pigment. All the strains showed antibacterial activity when cultivated in liquid media. The pigment differed from all known pigments. It is probably a new natural compound.

[Utilization of yeast mutants with a defect in the cellular membrane in the search for anticancer antibiotics]. / Ispol'zovanie mutantov drozhzhei s defektom kletochnoi membrany pri izyskanii protivorakovykh antibiotikov

The mutants of Saccharomyces cerevisiae, strain FL 599-I B with defect cell membranes are selectively inhibited by anticancer antibiotics with different molecular mechanisms of action on DNA. At the same time they are insensitive to antibacterial antibiotics. Such mutants may be used as test-cultures in isolation of active agents with antitumor effect from complex mixtures of natural substances. The above test-object makes it easier to perform separation of antimour antibiotics from accompanying bacterial inhibitors.

[Possibility of the early identification of polyene antibiotic producers]. / O vozmozhnosti rannei identifikatsii produtsentov polienovykh antibiotikov

A method for identification of polyenic antibiotics at early stages of their screening was developed using the known fact of high affinity of polygens and steroids. It was found that addition of cholesterol or ergosterol to the nutrient medium in a concentration of 100 gamma/ml eliminated the inhibitory effect of the polyenic antibiotics. Screening of the antibiotic-producing actinomycetes simultaneously on 2 media, i.e. with and without cholesterol using the yeast test-organisms provided identification of actinomycetes producing polyenic antibiotics. The selective capacity of 3 yeast cultures, i.e. Sacch. cerevisiae, Cand. albicans and Tor. globosa 11-3 as test-organisms for screening polyenic antibiotics was compared. It was shown that mitochondrial mutant 11-3 of Tor. globosa was a highly sensitive model for identification of actinomycetes producing polyenic antibiotic, since 23% of the actinomycetes possessing an activity against that organism produced substances of the polyenic nature. All the strains of the actinomycetes screened with the help of Cand. albicans and Sacch. cerevisia were the same as those detected with the help of mutant 11-3 of Tor. globosa.