[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.

[The antibiotic varigomycin--a new representative of the carbonyl-conjugated pentaenes]. / Antibiotik varigomitsin--novyi predstavitel' karbonil-kon''iugiro-vannykh pentaenov.

In screening new antibiotics, varigomycin produced by a new fungal species Streptomyces variegatus Sveshnikova et Timuk was isolated. By physicochemical properties varigomycin belongs to carbonyl conjugated pentaens. It is a new representative of this antibiotic group. Varigomycin differs from the known representatives of this group by the presence of glucose, sugar in its molecule.

[New species of Actinomadura recticatena sp. nov. and its antibiotic properties]. / Novyi vid Actinomadura recticatena sp. nov. i ego antibioticheskie svoistva.

Actinomadura cultures were isolated from soil samples collected in Turkmenistan, the Moscow, Kursk and Volgograd regions. The cultures were described as representatives of a new species (Actinomadura recticatena, Preobrazhenskaya et Galatenko, sp. nov). The hydrolysates of intact cells of the cultures contain mesodiaminopumelic acid, galactose and madurose. The species is characterized by straight spore chains, wrinkled spore surface, cream-colored aerial mycelium and brown substrate mycelium with pinkish or slightly violet shade. The cultures produce no soluble pigments, including the melanoid ones. The red-violet fraction of the pigments responsible for the pinkish and violet shades of the substrate mycelium belongs to the antibiotics of the griseorodin-rubromycin group.

[Formation of an antibiotic of the siomycin group by a Streptomyces corchorusii 1401 culture]. / Obrazovanie antibiotika iz gruppy siomitsina kul'turoi Streptomyces corchorusii 1401.

Streptomycete 1401 inhibiting the growth of gram-positive organisms was isolated from a soil sample in the screening of new antibiotics. By its cultural and morphological properties the culture was classified as Str. corchorusii. An antibiotic complex was isolated from the mycelium of the culture. The main component of the complex was shown to belong to the antibiotics of the siomycin group.

[Search for new antibiotics of the cyclosporin group]. / Izyskanie novykh antibiotikov iz gruppy tsiklosporinov.

A total of 160 fungal cultures belonging to Trichoderma were isolated from soil samples collected in various regions of the USSR. The cultures were tested for production of antibiotics of the cyclosporin group, having a narrow antifungal spectrum. It was found that 7 cultures produced substances having a selective inhibitory effect on Asp. niger and no activity against gram-positive and gram-negative organisms. An antibiotic substance close by its physicochemical properties to cyclosporins was isolated from T. viride 122.

[Antibiotic formation from a pyrimidine base group and an aminoglycoside group by a Streptomyces coeruleoaurantiacus sp. nov. culture]. / Obrazovanie antibiotikov iz gruppy pirimidinovykh osnovanii i gruppy aminoglikozidov kul'turoi Streptomyces coeruleoaurantiacus sp. nov.

An actinomycete strain 4009 was isolated from a soil sample collected in Volgograd. The strain showed a broad antibacterial spectrum. It produced antibiotics belonging to 2 different groups of chemical compounds, i.e. amycetin from the group of pyrimidine bases and nebramycin from the group of aminoglycosides. The antibiotic-producing organism is described as a type strain of Streptomyces coeruleoaurantiacus sp. nov. The new species is characterized by spiral spore chains, wart-like spore surface, blue aerial mycelium and dark yellow, orange-yellow or brown-orange-yellow substrate mycelium, the absence of soluble pigments on synthetic media and secretion of melanin pigments on the Tresner medium. Various conditions for submerged production of the antibiotic were studied.

[Transfer of species of the genus Actinomadura Lechevalier et Lechevalier 1970 to the genus Nocardiopsis Meyer 1976]. / O perevode nekotorykh vidov roda Actinomadura Lechevalier et Lechevalier 1970 v rod Nocardiopsis Meyer 1976.

The type cultures of four Actinomadura species (A. africana, A. coeruleofusca, A. flava, A. longispora) were studied and compared with the type culture belonging to the genus Nocardiopsis. In their morphological properties and in the composition of the cell wall, these cultures were shown to be closer to the genus Nocardiopsis Meyer 1976 rather than to the genus Actinomadura Lechevalier et Lechevalier 1970. Basing on these data, the species have been transferred to the genus Nocardiopsis.

[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.

[New producer of amphomycin-group antibiotics]. / Novyi produtsent antibiotikov gruppy amfomitsina.

An actinomycetous culture 33 inhibiting the growth of grampositive bacteria was isolated from a soil sample. The culture was classified as belonging to Streptomyces albogriseolus. It was found that culture 33 produced antibiotics of the amphomycin group. The antibiotic complex consists of 2 components, one of which is identical to amphomycin and the other differs from it. Conditions for the complex production were also investigated. Production of amphomycin by Str. albogriseolus was observed for the first time.

[Intensification of the cytostatic action of adriamycin and carminomycin by amphotericin B]. / Ob usilenii tsistostaticheskogo deistviia adriamitsina i karminomitsina amfoteritsinom B.

Amphotericin B has a significant cytostatic effect on lymphadenosis cells of mice NK/LY. In a concentration of 6 units/ml it inhibits an increase in total nucleic acids by 50 per cent. Such cytostatic effect of amphotericin B combines with the effect of carminomycin and adriamycin. In concentrations having no cytostatic effect amphotericin B does not enhance the action of adriamycin and carminomycin on tumor cells.

Production of rhodomycins in Streptomyces griseoruber 4620.

The strain Streptomyces griseoruber 4620 produces, besides the anthracycline antibiotics beromycins, some other anthracyclines of the rhodomycin type. Twelve isolates exhibiting a higher antibiotic activity (up to 2.5X), as compared to the parent strain, were obtained after a spontaneous selection. The following species were isolated from the hydrolysate of mycelial extract: beta-rhodomycinone, beta-isorhodomycinone, alpha 2-rhodomycinone, epsilon-rhodomycinone and 10-deoxy-beta-rhodomycinone, which has not yet been described.

Spontaneous variability of Streptomyces glomeratus, a producer of the amthracycline antibiotics beromycins.

Spontaneous variants of the beromycin-producing strain Streptomyces glomeratus 3980 were divided into five groups (A-E) according to increasing antibiotic activity. The most active variants (group E) differed from the other types and the wild strain by a suppressed ability to produce aerial mycelium and melanoid piogment and by an increased production of propionic acid. Strains with a 12-fold higher antibiotic production capacity (with respect to strain 3980) were obtained by selection of superior segregants from submerged cultures of the E type.

Effect of cultivation conditions on the activity of the beromycin producer Streptomyces glomeratus 3980 and its spontaneous variants.

Optimal conditions for the submerged cultivation of Streptomyces glomeratus 3980, producer of the anthracycline antibiotics beromycins, and its variants were sought in media with glucose, soybean meal and salts differing in the content of ammonium sulphate. As compared with the original activity of the strain the antibiotic titre of some variants increased about 12 times on increasing the glucose concenration from 3 to 5%, or on omitting CaCO3 from the medium (i.e. under conditions leading to an increased production of propionic acid and suppression of production of the melanin-like pigment). In melanin-less variants accumulating propionate even under standard conditions the activity increased about 18-40 times in the medium with 3% glucose and 0.2% CaCO3 under conditions of more intensive aeration (i.e. under conditions when no propionic acid accumulated). Individual strains also differed in the requirement for (NH4)2SO4 in the medium, their response to changes of volume of the vegetative inoculum and semsitivity to MgSO4 x 7H2O. The biosynthetic activity of all strains was inhibited by the addition of ZnSO4 x 7H2O or CaCl2 and substitution of glucose with starch, lactose or sucrose.

[Formation of antibiotic 2562 by a culture of the actinomycete, Streptomyces griseovariabilis]. / Obrazovanie antibiotika 2562 kul'turoi aktinomitseta Streptomyces griseovariabilis.

An actinomycetous culture 2562 inhibiting the growth of gramnegative bacteria was isolated from a soil sample. The culture was classified as Streptomyces griseovariabilis. It was found that culture 2562 produced an antibiotic belonging to the group of novobiocin. It consists of 2 components. One of them is identical to chlorobiocin and the other is a minor component of this group. Some parameters of the antibiotic complex production by strain 2562 under submerged conditions were studied. Nutrient media providing the predominant biosynthesis of the first (main) or the second component of the antibiotic were developed.

[Formation of the antibiotic complex 4041 by a culture of Actinoplanes ianthinogenes subsp. octamycini subsp. nov]. / Obazovanie antibioticheskogo kompleksa 4041 kul'turoi Actinoplanes ianthinogenes subsp. octamycini subsp. nov.

A new variety of Actinoplanes, named Actinoplanes ianthinogenes subsp. octamycini Gause et Svechnikova is described. It produces an antibiotic complex consisting of purpuromycin and a new antibiotic belonging to the group of polyens, i. e. octamycin. Maximum accumulation of the above antibiotics in the mycelium was observed in the soybean-glycerol medium.

[Role of antibiotics in the ecology of actinomycetes]. / Rol' antibiotikov v ékologii aktinomitsetov.

The organisms producing ristomycin, rifamycin, lincomycin, tobramycin, rubomycin carminomycin, olivomycin, bleomycin and actinomycin D were practically not sensitive to their own antibiotics in the concentrations close to those produced during the biosynthetic process. At the same time other actinomycetous species close to the above organisms were suppressed to a significant extent by their antibiotics in the same concentrations. The experimental data indicated that the antibiotics had a protective effect on the organisms producing them and played a significant role in ecology of the actinomycetes.