Ascomycete fungi isolated in Central Siberia from canker lesions of Abies sibirica Ledeb. were assigned to the genus Corinectria Gonzalez Chaverri. Our earlier research has shown four Corinectria Siberian strains to be significantly different genetically from the known Corinectria spp. This work investigated the secondary metabolites of 23 morphologically similar Corinectria Siberian strains and their phytotoxicity. The strains were divided into two types by their morphological and cultural traits, MCT1 and MCT2. The MCT1 strains synthesized the meroterpenoids ilicicolins A and B, ilicicolin A epoxide and chlorocylindrocarpol; the MCT2 strains produced ilicicolins C, D (ascochlorin), F and ascofuranol. The phytotoxicity of the Corinectria strains showed a significant heterogeneity to Picea obovata seeds and was exhibited by 31

Fungal strains isolated in the Krasnoyarsk Territory from dead caterpillars of the Siberian silkworm Dendrolimus sibiricus Tschetverikov, found in the litter and crown of Abies sibirica Ledeb., were assigned to the species Cordyceps militaris (L.) Fr., based on morphological and genetic methods. The strains were highly active producers of such bioactive compounds as polysaccharides (PS), adenosine, and cordysinin B. Cordysinin B has not been previously reported in the species C. militaris. It was found that PS production was more influenced by the method of fungal cultivation than by the carbon substrate. The highest production of PS (6.0–6.7 g/L) and nucleosides (390 mg/L) by C. militaris 11-5 was observed during submerged cultivation on sucrose using abiopeptide. When studying the biosynthesis of PS during growth of the fungus, it was found that the synthesized PSs were consumed by the culture when the concentration of the carbon substrate in the medium decreased and apparently served as reserve sources of carbon.

Most Fusarium species are known as endophytes and/or phytopathogens of higher plants and have a worldwide distribution. Recently, information discovered with molecular tools has been also published about the presence of these fungi in the microbiome of truffle fruiting bodies. In the present work, we isolated and identified three Fusarium strains from truffle fruiting bodies. All isolates were assigned to the same species, F. commune, and the strains were deposited in the All-Russian Collection of Microorganisms under accession numbers VKM F-5020, VKM F-5021, and VKM F-5022. To check the possible effects of the isolated strains on the plants, the isolates were used to infect sterile seedlings of Sarepta mustard (Brassica juncea L.). This model infection led to a moderate suppression of the photosynthetic apparatus activity and plant growth. Here, we present characteristics of the F. commune isolates: description of the conidial morphology, pigmentation, and composition of the mycelium fatty acids. Overall, this is the first description of the Fusarium cultures isolated from truffle fruiting bodies. Possible symbiosis of the F. commune strains with truffles and their involvement in the cooperative fatty acid production are proposed.

Scarce research into the secondary metabolites of the fungi Pseudogymnoascus spp. has shown a hidden biosynthetic potential for biologically active compounds. This work investigated the biosynthesis of secondary metabolites by two Pseudogymnoascus fungal strains, VKM F-4518 and VKM F-4519, isolated from the surface soil layer of the Kolyma Lowland, Russia, in the Arctic. In these strains, 16-membered trilactone macrolides, (+)-macrosphelides A and B, were identified using 1D and 2D NMR, UHRMS, and optical rotation data. In the fungi of this genus, these metabolites were found for the first time. The studied strains are highly active producers of macrosphelide A, which is being considered as a promising agent for the cure of cancer. Using the antiSMASH secondary metabolite analysis tool, we found that the genome of strain VKM F-4518 contained 32 of the biosynthetic clusters of the secondary metabolite genes (BGC) and that of VKM F-4519 had 17 BGCs. Based on the comparison of the cluster of macrotriolide genes from the fungus Paraphaeosphaeria sporulosa, we found the complete supposed cluster BGCs of macrosphelides in the genomes of two Pseudogymnoascus strains using the BLAST+ program.

— Microscopic fungi form and excrete numerous and diverse secondary metabolites, including pigments of various colors, which may be used as an alternative to chemical and plant colorants used in industry. Azaphilone compounds, first discovered in fungi of the genus Monascus , are among the promising classes of fungal pigments . The review analyzes the publications on formation of azaphilone-type pigments in Monascus fungi, as well as in Talaromyces and Aspergillus cavernicola . Brief information is provided concerning the antimicrobial, antitumor, anti-inflammatory, and hypolipidemic activities of azaphilone pigments. Possible strategies for increasing the efficiency of the production process and directed synthesis of yellow, orange, and red pigments and their derivatives are discussed. In general, the review provides for assessment of the role of azaphilone pigments, as well as of the prospects and ways to expand their production for use as natural dyes in various fields.

Fusaric acid (FA) is a secondary fungal metabolite, which is widespread on corn and corn-based feed and food; FA has non-specific toxicity. Biosensor method is an express and easy-to-use method for quantitative and qualitative assessment of FA effect. Search for cultures has been performed for the formation of laboratory models of FA biosensor with the Clark-type oxygen electrode as transducer: respiration intensity of chosen cultures changed in the presence of FA. Resting cells of Fusarium oxysporum f. sp. vasinfectum and Bacillus subtilis were used as receptors of the amperometric biosensor for FA determination in aqueous solution. To enhance the sensitivity of detection, induction by substrate was performed for Bacillus subtilis. Response-concentration linear dependencies were obtained in a range of 0.5-500 FA mg/L. Biosensor models were applied to characterize influence of FA on microbial cells and investigate some features of FA transport. The dependences of the cells' response to FA on FA concentration were obtained; the kinetic parameters S0.5 and Vmax were determined for each culture. Inhibition-threshold FA (Sit) concentrations were similar for both studied cultures. At concentrations lower than Sit, the process of simple diffusion governed FA transport into cells and caused the cells' response to FA for non-induced culture.

Due to the ever-increasing demand for healthy and safe food, much attention has been gained by natural food colorants. This study showed the culture fluid extract of the fungus Aspergillus cavernicola VKM F-906 to contain red pigment and monasnicotinic acid (MNA) in predominant amounts. The structure of the pigment corresponded to cis-cavernamine (red pigment, RP). Two tautomers, NH and OH forms, in rapid equilibrium were present in a solution of RP. The critical factors for RP to form were the presence of NH4+ salt and pH 6.3-6.5. In vitro experiments showed that MNA was synthesized from RP as a result of chemical transformations without the participation of enzymes. In this case, the main influence on the reaction rate is exerted by the pH of the medium, which is associated with the keto-enol tautomerism of RP in solution. The culture broth extract and MNA exhibited antifungal activity against Fusarium fungi.

The methods for increasing the isolation of carotenoids from yeast producer cultures have been compared. It was shown that the optimal procedure is microwave pretreatment (2450 GHz, 600 W, 40 s) with subsequent extraction of the target products with methanol. Additives of sodium persulfate or ammonium persulfate to aerated culture medium provided additional oxygen sources for the yeast and increased the medium redox potential. The introduction of persulfate led to a 1.3-fold increase in the content of colored carotenoids in the R. dubiovatum VKPM Y-305 biomass as compared to the control without persulfate. In the R. sphaerocarpum VKPM Y-1559 biomass, persulfate at concentrations of 0.15 g/L and 0.50 g/L increased the content of colored carotenoids by 1.3 and 1.4 times, respectively. The optimal persulfate concentent depends on the yeast growth phase and time of exposure to the compound. Higher persulfate concentrations resulted in increased redox potential and discoloration of carotenoids, though without yeast cell death. yeasts, carotenoids, medium redox potential, persulfate

Production of carotenoids with red yeasts is a promising area of industrial biotechnology. All spectrophotometrical ("classic") analyses of carotenoids are based on preliminary extraction of the water-insoluble carotenoids; thus, these analyses are precise but complicated and time consuming. This paper presents a simple method to evaluate the red-colored carotenoids in yeast biomass by its color, without extraction. The method is based on digital characteristics of the biomass whole coloring, and it has already been successfully applied in other areas of biology: to compare plant and animal objects. In contrast to spectrophotometry measuring the amount of light that can pass through a solution, the biomass photo is a reflected color of the insoluble compounds. Application of this method to microorganisms permitted to compare the yeast strains and the effects of substrates or culturing regimes for any change in the red-colored pigments. The proposed rapid method was compared with the classic analyses of the carotenoids and showed that evaluation of red-colored carotenoids by the whole coloring of biomass can be used to discover changes in the yeast carotenoid production. In whole, the paper contributes method which is new for pigmented microorganisms and has a potential application in biotechnology.

It has been found that monasnicotinic acid (MNA) isolated from the fungus Aspergillus cavernicola VKM F-906 reduces the proliferation and migration of human prostate cancer cells LnCaP and inhibits the AKT–mTORC1 and FAK–Src signaling pathways. However, MNA also increases the level of HSP60 and the phosphorylation of c-Jun, factors that stimulate the vital activity of cancer cells. MNA-induced cellular responses appear only after 48 h, which indicates the involvement of either the products of MNA metabolism or tautomers arising during the MNA protonation due to the growth of cell cultures and utilization of the compound by human cells. These results suggest that MNA is a promising compound for the production of various derivatives that would inhibit oncogenic signaling pathways without stimulating the factors providing the survival of tumor cells.

From undisturbed Antarctic habitats (permafrost sediments 30–150 thousand years of age, water of Radok Lake) and superficial deposits contaminated with petroleum products, we isolated 14 and 9 strains of Penicillium fungi, respectively. Comparison of the fungal complexes showed them to differ by species composition; only two species— P. palitans and P. solitum —were in the species lists of both groups. The identified secondary metabolites in the investigated strains belonged to diketopiperazine (group of roquefortines, rugulosuvin B), benzodiazepine (anacin, cyclopenins), quinoline alkaloids (viridicatins), clavine ergot alkaloids (α-cyclopiazonic acid, festuclavine, fumigaclavines), polycyclic indole alkaloids (communesin B, chaetoglobosin A), amino acid derivatives (N-acetyltryptamine, chrysogins, penicillin G), polyketides (citreoviridin A, mycophenolic acid), and terpenes (andrastins, phomenone). Strains isolated from anthropogenically altered habitats produced a more complete and characteristic profile of exometabolites, as compared with strains isolated from undisturbed habitats. It is only from contaminated soils there were isolated fungi that produced more structurally diverse secondary metabolites pertaining to polycyclic indole alkaloids and terpenoids. The fungi isolated from contaminated samples can be used in biodegradation of oil spills and bioremediation of the environment, and also as producers of promising biologically active compounds.

В статье изложена история изучения численности и разнообразия мицелиальных грибов в образцах глубинных горизонтов и активного слоя Арктики и Антарктиды, установленных с помощью традиционных микробиологических методов. На обширном экспериментальном материале показано, что общая численность грибов в глубинных горизонтах антарктических отложений в целом ниже, чем в Арктике. Подтверждается микроочаговое распределение грибов в многолетнемерзлых отложениях, а также обсуждается их таксономический состав. Анализируется видовое разнообразие и выявляются таксоны с высокой частотой встречаемости, среди которых находятся грибы родов Penicillium и Geomyces (tm Pseudogymnoascus), адаптированные к существованию в экстремальных экотопах. Обсуждаются особенности их метаболизма при действии разных стессоров и реакции грибов рода Geomyces на изменение абиотических факторов на генетическом уровне. The article sets out the history of the study the number of mycelial fungi established using traditional microbiological methods in deep horizons and in the samples of the active layers of the Arctic and Antarctica. An extensive experimental data shows that the total number of fungi in the deep horizons of the Antarctic sediments as a whole is lower than in the Arctic. The microfocal distribution of fungi in permafrost deposits is confirmed, and their taxonomic composition is also discussed. Biodiversity is analyzed and the taxa with a high frequency of occurrence are detected. Among them there are fungi from genera Penicillium and Geomyces (tm Pseudogymnoascus) adapted to life in extreme ecotopes. The features of their metabolism under the influence of different stressors and the reaction of Geomyces on the changing of abiotic factors at the genetic level are discussed.

The composition of secondary metabolites from strains Heterobasidion genus isolated in central and western Siberia and in South Korea were studied. Morphological–cultural and molecular-genetic methods were used to assign the cultures to the species of H. annosum (Fr.) Bref. (five strains), H. abietinum Niemelä & Korhonen (four strains), and H. ecrustosum Tokuda, T. Hatt. & Y.C. Give (one strain). Fomannoxin predominated in the metabolome profiles of three H. annosum strains and all H. abietinum strains. Two strains of H. annosum synthesized fomannoxin-related compounds: 2-(2-hydroxypropan-2-yl)-2,3-dihydrobenzofuran-5-carbaldehyde and 2-(2-hydroxypropan-2-yl)benzofuran-5-carbaldehyde. Fomannosin and its precursors were identified in H. annosum 45-2. It was shown that the composition of the fermentation medium affected the number and range of the synthesized metabolites. Under in vitro conditions, all H. annosum and H. abietinum strains exhibited phytopathogenic effects on Pinus sylvestris L. seedlings, causing necrotic damage to stems of various degrees and plant death. Higher phytopathogenicity is characteristic of H. annosum strains: maximal aggressiveness was observed in H. annosum 45-2 with the greatest diversity of compounds in the metabolome profile and active fomannoxin production.

МЕТАБОЛОМИКА ГРИБОВ РОДА PENICILLIUM Т.В.Антипова к.б.н., ст.науч.сотрудник, Институт биохимии и физиологии микроорганизмов им.Г.К.Скрябина РАН (ИБФМ) обособленного подразделения ФИЦ ПНЦБИ РАН

Two new austalide meroterpenoids, named austalides V and W (1 and 2), were isolated from the fungus Aspergillus ustus VKM F-4692. Their structures were elucidated by extensive spectroscopic analysis and by comparison with related known compounds. The main structural feature of both compounds is a tetrahydrofuranyl ring (G), a structural fragment, first found in austalides. Austalides V (1) and W (2) were able to inhibit the propagation of prostate and bladder cancer cells; this biologic activity is possibly related to the inhibition of a number of key pathways regulating cell growth and migration.