Comparative characteristics of some actnomycetes, producers of antifungal antibiotics related to chondamycin]

Three actinomycetous strains designated as LIA-0773, LIA-0783 and LIA-0780 were isolated from various soil samples. The cultures actively inhibited the growth of Trichophyton gipseum and produced a non-polyenic antibiotic of the chondamycin type. The strains were identified with Act. griseochromogenes Fukunaga et. al., 1955. The cultures differed within the species by some morphological, cultural, physiological and antibiotic properties, as well as by the component composition of the antibiotic produced. Thus, strain LIA-0773 had larger spiral sporophores, satisfactorily hydrolized starch and inverted sucrose. The strain inhibited the growth of not only the fungi but also grampositive bacteria and mycobacteria and produced an antibiotic composed of 6 components. Strain LIA-0780 had small sporophores with close spirals and low amilolytic activity. It inhibited only the growth of the fungi and produced a monocomponent antibiotic. Strain LIA-0783 was intermediate. By its biological properties it was closer to strain LIA-0780. The antibiotic produced by it consisted of 6 components, while by its physico-chemical properties the antibiotic was close to that produced by strain LIA-0780. All the 3 actinomycetous cultures were considered as different variants of Act. griseochromogenes Fukunaga et al., 1955.     

New heptaene antibiotic, flavomycin, formed by Act. flavus var. geptinicus var. nov]

An actinomycetous culture LIA-0734 was isolated from a soil sample. By its morphologo-cultural properties it was close to Act. flavus and differed from the latter in the sporophores, colour of the substrate mycelium on synthetic media amd markedly pronounced antagonism with respect to yeasts and yeast-like fungi. The culture was classified as Act. flavus var. geptinicus var. nov. The actinomycete produced new aromatic heptaens: flavomycins A and B. Their physico-chemical and biological characteristics and singularity are presented.     

Actinomyces fulvoviolaceus ver. achromogenes var. nov., a producer of the new heptaene complex, fulvomycin]

An actinomycetous culture designated as LIA-0721 was isolated from a soil sample. It was close to Act. fulvoviolaceus by its morphologo-cultural features and differed from it in production of melanoid pigments and the spectrum of carbohydrate assimilation. This justified its classification as Act. fulvoviolaceus var. achromogenes var. nov. The culture produced new aromatic heptaens, i. e. fulvomycins A, B and C. Their physico- chemical and biological characteristics are presented.     

Streptomyces coerulatus, a producer of the nonaromatic heptaene, LIA-0735

An actinomycete designated as Streptomyces coerulatus LIA-0735 was isolated from a soil sample collected in the Alma-Ata region. The strain produces a nonaromatic heptaenic antibiotic with a very low inhibitory effect on the growth of gram positive bacteria, yeasts and actinomycetes. By a number of features antibiotic LIA-0735 differs from the known heptaens of the nonaromatic group.     

Physiochemical properties of LIA-0191 A and B antibiotics

An antifungal antibiotic LIA-0191 was isolated from the mycelium by methanol extraction. It was shown with thin-layer chromatography that it consisted of components A and B. Component A was isolated with collumn chromatography on silica gel, recrystalization from the solvent mixture as a monocomponent crystalline substance. On the basis of the physicochemical and biological properties it was identified with sentacidin. Component B was obtained from preparation LIA-0191 by the method of counter-current distribution and recrystalization from methanol. Comparison of its physico-chemical and biological properties with those of the known purines and pyrimidine pyrrol showed that antibiotic LIA-0191 B is new.     

Streptoverticillium griseoviridum n. sp., a producer of the candidin-amphotericin B group, antifungal heptaene nonaromatic antibiotic 0185]

An actinomyceteous strain LIA-0185 producing a heptaenic non-aromatic antibiotic of the candidin type was isolated from a soil sample taken in the Georgian SSR under the programme of screening antifungal antibiotics. The taxonomic study of the strain showed that it belonged to the series of viridoflavum and had the following main taxonomic features: the sporophores in the whorls, straight, remote: the aerial mycelium from yellow to dark-olive-grey; the substrate mycelium olive; the soluble pigment absent; the melanine pigment was produced on the peptone medium; the culture formed H2S; assimilated glucose, mannose, inozide and to a lesser extent fructose; did not assimilate arabinose, xylose, sucrose, lactose, ramnose and raffinose. The strain inhibited the growth of yeast and fungi, grampositive bacteria and actinomycetes and produced a complex of non-aromatic heptaenic antibiotics. The actinomycete differed from the other whorl cultures. It was classified as a new species Sv. griseoviridum sp. nov. The antibiotic complex was a mixture of 2 components, i. e. I and II present approximately in equal amounts. Component II was analogous to candidin. Component I was a new original substance.     

Polymorphism of a culture of the chromomycin producer, Actinomyces aburaviensis var. verrucosus]

Polymorphism of the chromomycin-producing orgnaism Act. aburaviensis var. verrucosus 144--3 was studied. The stable variants differed in the morphologo-cultural properties, assimilation of the carbon sources, the component composition of the luminescence substances and the quantitative property of the antibiotic production. A substance with violet luminescence was found in the culture of varient I in addition to chromomycin. Similarity of the phenotypes observed in variants 1 and 2 when grown on complex organic media is explained by intensive chromomycin production by variant 1 on such media. Active colonies may be selected according to the colour due to chromomycin. Forms with an activity almost 4 times higher than that of the initial culture were found among the colonies of variant 2.     

Actinoplanes brasiliensis INA 3802--a producer of peptide antibiotics]

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.     

抗生素AGPM发酵过程中蛋白质表达差异的研究

由土壤中筛选到一能产生新型抗肿瘤抗生素AGPM的藤黄灰链霉菌株,应用蛋白质双向电泳方法,比较了藤黄灰链霉菌在发酵24h与72h蛋白质表达的差异,发现在发酵72h有17个蛋白质差异点出现,此外还发现一些蛋白质的含量明显高于24h的同种蛋白含量,这表明这些蛋白可能与抗生素AGPM的合成以及和菌体的生长等有关。     

Study of the optimal conditions of preservation of cephalosporin C-producing fungus Acremonium chrysogenum

The influence of various preservation conditions of viability and antibiotic activity of Acremonium chrysogenum 281A and 305A strains producing cephalosporin C was studied. Cryogenization of the culture in the form of suspension of the vegetative mycelium in 20 per cent glycerol solution at a rate of 1 degree/min showed to be advantageous over lyophilization and L-drying. Cryogenization under such conditions provided rather high viability of the culture and preservation of its initial antibiotic activity for the period of its storage for at least 1.5 years in liquid nitrogen at a temperature of -196 degrees C.     

Characterization of the process for the biosynthesis of the actaplanin complex by Actinoplanes missouriensis

The production of the antibiotic actaplanin by Actinoplanes missouriensis was characterized in a high yielding process. The data generated, indicate that the antibiotic is synthesized during a period of declining cell mass as estimated by dry weight and viability. Further study demonstrated that the producing culture binds actaplanin and is inhibited by the antibiotic in the soluble form.     

Formation of antibiotic 2562 by a culture of the actinomycete, 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.     

Intergeneric hydridization of the actinomycetes Streptoverticillium mycoheptinicum and Streptomyces coelicolor

Intergeneric crossing of the actinomycetes Streptoverticillium mycoheptinicum and Streptomyces coelicolor yielded recombinants which were mostly nonviable and unstable despite a relatively high frequency (10(-2)-10(-4)) at which their colonies appeared. The rare viable and stable recombinants were prototrophs. The structure of antibiotics in the hybrid cell may be modified as follows from the differences in the antibiotic activity of the LIA-973 hybrid and the parent strains.     

Green fluorescent protein-marked Pseudomonas fluorescens: localization, viability, and activity in the natural barley rhizosphere.

The gfp-tagged Pseudomonas fluorescens biocontrol strain DR54-BN14 was introduced into the barley rhizosphere. Confocal laser scanning microscopy revealed that the rhizoplane populations of DR54-BN14 on 3- to 14-day-old roots were able to form microcolonies closely associated with the indigenous bacteria and that a majority of DR54-BN14 cells appeared small and almost coccoid. Information on the viability of the inoculant was provided by a microcolony assay, while measurements of cell volume, the intensity of green fluorescent protein fluorescence, and the ratio of dividing cells to total cells were used as indicators of cellular activity. At a soil moisture close to the water-holding capacity of the soil, the activity parameters suggested that the majority of DR54-BN14 cells were starving in the rhizosphere. Nevertheless, approximately 80% of the population was either culturable or viable but nonculturable during the 3-week incubation period. No impact of root decay on viability was observed, and differences in viability or activity among DR54-BN14 cells located in different regions of the root were not apparent. In dry soil, however, the nonviable state of DR54-BN14 was predominant, suggesting that desiccation is an important abiotic regulator of cell viability.     

New producer of carminomycin, Actinomycer cremeospinus sp. nov.]

An actinomycete strain No. 85 was isolated from a soil sample on media with bleomycin. It was described as a representative of a new species. Actinomyces cremeospinus sp. nov. An antibiotic substance identical with carminomycin, an antitumor antibiotic was isolated from the culture fluid of the strain.     

Preservation of Claviceps purpurea, the producer of peptide ergot alkaloids, by the method of freeze drying

A saprotrophic strain of Claviceps purpurea VNIIA 312A, an organism producing peptide +ergot alkaloids with prolactin inhibiting activity was shown to die under lyophilization conditions. To provide long-term storage of strain 312A, L-drying or drying under vacuum from liquid state was used with success. Three protective media were tested. Favourable results were obtained by using 25 per cent maltose solution as a protective medium. Preservation of the culture viability was accompanied by maintenance of the culture capacity for active formation of the biomass and production of +ergot alkaloids.     

Green Fluorescent Protein-Marked Pseudomonas fluorescens: Localization, Viability, and Activity in the Natural Barley Rhizosphere

The gfp-tagged Pseudomonas fluorescens biocontrol strain DR54-BN14 was introduced into the barley rhizosphere. Confocal laser scanning microscopy revealed that the rhizoplane populations of DR54-BN14 on 3- to 14-day-old roots were able to form microcolonies closely associated with the indigenous bacteria and that a majority of DR54-BN14 cells appeared small and almost coccoid. Information on the viability of the inoculant was provided by a microcolony assay, while measurements of cell volume, the intensity of green fluorescent protein fluorescence, and the ratio of dividing cells to total cells were used as indicators of cellular activity. At a soil moisture close to the water-holding capacity of the soil, the activity parameters suggested that the majority of DR54-BN14 cells were starving in the rhizosphere. Nevertheless, approximately 80% of the population was either culturable or viable but nonculturable during the 3-week incubation period. No impact of root decay on viability was observed, and differences in viability or activity among DR54-BN14 cells located in different regions of the root were not apparent. In dry soil, however, the nonviable state of DR54-BN14 was predominant, suggesting that desiccation is an important abiotic regulator of cell viability.     

The antimicrobial activity of Aspergillus fumigatus is enhanced by a pool of bacteria

In a screening program for new antibiotic producers, a strain of Aspergillus fumigatus was isolated from Brazilian soil samples. A pool of autoclaved bacteria was added to part of the fungus culture on the second day of fermentation to increase antibiotic production. The chloroform extract from the culture broth to which the pool of autoclaved bacteria was added showed an increase of 55%, 63% and more than 100% in activity against Staphylococcus aureus, Candida albicans and Micrococcus luteus, respectively. Also, the HPLC chromatographic profiles of the chloroform extracts from both culture conditions were different. Two active compounds were isolated from the broth of the culture grown in the presence of pooled bacteria and were identified as 3,4-dimethoxyphenol and 1,3,5-trimethoxybenzene.     

Determining the environmental fate of a filamentous fungus, Trichoderma reesei, in laboratory-contained intact soil-core microcosms using competitive PCR and viability plating

Trichoderma spp. are used extensively in industry and are routinely disposed of in landfill sites as spent biomass from fermentation plants. However, little is known regarding the environmental fate of this biomass. We tracked the survival of T. reesei strain QM6A#4 (a derivative of strain QM6A marked with a recombinant construct) over a 6-month period in laboratory-contained, intact soil-core microcosms incubated in a growth chamber. Survival was tested in 3 different soils and the effect of a plant rhizosphere (bush lima beans, Phaseolus limensis) was investigated. Levels and viability of the fungus were determined, respectively, by quantitative competitive polymerase chain reaction analysis of total soil DNA extracts and dilution-plating of soil on a semiselective growth medium. Whereas chemically killed QM6A#4 became undetectable within 3 d, QM6A#4 added as a live inoculum decreased approximately 4- to approximately 160-fold over the first 1-3 months and then reached a steady state. After 4 months, soil cores were subjected to a 1.5-month simulated winter period, which did not significantly affect QM6A#4 levels. Throughout the experiment, QM6A#4 remained viable. These results indicate that, following release into the environment, live T. reesei will persist in soil for at least 2 seasons.