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Polychlorinated biphenyls (PCBs) belong to the organic pollutants that are toxic to humans and harmful to environments. Numerous studies dealing with the impact of PCBs on soil microorganisms have focused on bacterial communities. The effects of PCBs on fungal communities in three different PCB-polluted soils from former industrial sites were investigated using high-throughput sequencing of the internal transcribed spacer 1 region. Significant differences in fungal alpha diversity were observed mainly due to soil physico-chemical properties. PCBs only influenced the richness of the fungal communities by increasing it. Fungal composition was rather strongly influenced by both PCBs and soil properties, resulting in different communities associated with each soil. Sixteen Ascomycota species were present in all three soils, including Stachybotrys chartarum, Fusarium oxysporum, Penicillium canescens, Penicillium chrysogenum,Penicillium citrosulfuratum and Penicillium brevicompactum, which are usually found in PCB-polluted soils, and Fusarium solani, Penicillium canescens, Penicillium citrosulfuratum and Penicillium chrysogenum, which are known PCB degraders. This study demonstrated that PCBs influence the richness and the composition of fungal communities. Their influence, associated with that of soil physico-chemical properties, led to distinct fungal communities, but with sixteen species common to the three soils which could be considered as ubiquitous species in PCB-polluted soils.

Utilization of laccases in biotechnology and bioremediation has created a strong demand for the characterization of new enzymes and an increase in production of known laccases. Thus, additional research into these enzymes is critically needed. In this study, we report a comparative study of the biochemical and transcriptional properties of two different laccase isozymes from Trametes hirsuta 072 – the constitutive and inducible forms. A recombinant LacC enzyme was expressed in Penicillium canescens to characterize its properties. LacC is single-purpose enzyme, unlike LacA, which can operate efficiently under a wide range of temperatures and pHs (55–70 °C and pH 3–5, respectively). LacC has a lower RedOx potential than LacA and does not oxidize substrates containing amine groups. Expression of the lacC gene was selective compared to that of the lacA gene and increased significantly in the presence of complex synthetic compounds such as dyes and xenobiotics. This study shows that laccases from the multigene families of basidiomycetes differ significantly in their properties, thus providing a complementary effect during lignin degradation.

Plant biomass is the main type of organic material on Earth. The efficiency of biocatalytic conversion of plant raw materials determines the cost of their biotechnological processing to produce commercially valuable products such as organic alcohols and acids, carbohydrates, and hydrocarbons. New recombinant Penicillium canescens strains that produce not only their own enzyme complex but also heterologous cellulases (i.e., mutant and wild-type cellobiohydrolase I (CBH I) and endoglucanase II (EG II) of P. verruculosum) are constructed. Enzymatic agents (EAs) prepared on the basis of recombinant strains of P. canescens are found to be more active in the hydrolysis of crushed aspen wood. Yields of glucose and reducing sugars are observed 24–72 h after hydrolysis with EAs prepared in recombinant strains to be from 48 to 52 and 60 to 64%, respectively, higher than those for hydrolysis with EAs prepared in the initial recipient strain. The presence of N45A and N194A site-specific mutations introduced to reduce surface glycosilation thus results in a substantial increase in the yields of desired CBH I and EG II.

Recombinant strains Penicillium verruculosum were created which produce homologous endoglucanase 2 (Er2) and heterologous xylanase E (XylE) P. canescens. The recombinant strains were used for preparing new biocatalysts which are enzyme preparations (EP) enriched considerably with Er2 and XylE; the biocatalysts are highly active to plant non-starch polysaccharides (NPS) such as cellulose, β-glucan, xylan. Proteic chromatography was used for determining the qualitative and quantitative composition of the new EP to show that they contain (expressed as proportions of the total protein content) ca. 16–17 % Er2, 48–63 % XylE, 17–30 % cellobiohydrolase, while EP prepared with the recipient strain contained 1.4 % Er2, ca. 60 % cellobiohydrolase and no XylE. pH equal to 4.0 and 5.5 were optimal for the activity to cellulose (with respect to carboxymethylcellulose, CMC) and to xylanase, respectively, EP being active over a wide range of pH from 3 to 7. EP were active to CMC and xylanase at the temperature range from 20 to 80 °C with maxima at 60 and 70 °C. The activity of new EP to xylanase was practically not inhibited by protein inhibitors of rye.

Based on the experimental research on determining the role of functional groups of the cell wall in the microfungus Penicillium canescens in the process of Pd(II) biogenic precipitation, it is revealed that hydroxyl and, to a lesser degree, amine groups participate in the sorption process in a weakly acidic medium (рН ~ 6), which is the most typical for natural conditions. The role of carboxyl groups under these conditions is not clear. The results obtained are of certain interest for understanding the mechanisms of platinoid mineral formation in organogenic sequences.

Background Recombinant carbohydrases genes are used to produce transgenic woody plants with improved phenotypic traits. However, cultivation of such plants in open field is challenging due to a number of problems. Therefore, additional research is needed to alleviate them. Results Results of successful cultivation of the transgenic aspens (Populus tremula) carrying the recombinant xyloglucanase gene (sp-Xeg) from Penicillium canescens in semi-natural conditions are reported in this paper for the first time. Change of carbohydrate composition of wood was observed in transgenic aspens carrying the sp-Xeg gene. The transformed transgenic line Xeg-2-1b demonstrated accelerated growth and increased content of cellulose in wood of trees growing in both greenhouse and outside in comparison with the control untransformed line Pt. The accelerated growth was observed also in the transgenic line Xeg-1-1c. Thicker cell-wall and longer xylem fiber were also observed in both these transgenic lines. Undescribed earlier considerable reduction in the wood decomposition rate of the transgenic aspen stems was also revealed for the transformed transgenic lines. The decomposition rate was approximately twice as lower for the transgenic line Xeg-2-3b in comparison with the control untransformed line Pt. Conclusion A direct dependence of the phenotypic and biochemical traits on the expression of the recombinant gene sp-Xeg was demonstrated. The higher was the level of the sp-Xeg gene expression, the more pronounced were changes in the phenotypic and biochemical traits. All lines showed phenotypic changes in the leave traits. Our results showed that the plants carrying the recombinant sp-Xeg gene do not demonstrate a decrease in growth parameters in semi-natural conditions. In some transgenic lines, a change in the carbohydrate composition of the wood, an increase in the cell wall thickness, and a decrease in the rate of decomposition of wood were observed.

Endoglucanase IIa from Penicillium verruculosum (PvCel5A) has three potential N-glycosylation sites: Asn19, Asn42 and Asn194. In order to study the role of N-glycosylation, the wild type (wt) PvCel5A and its mutant forms, carrying Asn to Ala substitutions, were cloned into Penicillium canescens. All forms of the rPvCel5A were successfully expressed and purified for characterization. The MALDI-TOF mass spectrometry peptide fingerprinting showed that N-glycans linked to Asn42 and Asn194 represent variable oligosaccharides, according to the formula (Man)1-9(GlcNAc)2. No evidence for Asn19 glycosylation was found. Mutations had no notable effect on the enzyme thermostability; however, the N-linked glycans stabilized the enzyme against proteolytic attack. For N42A and N194A mutants, a slight shift of pH-optimum to pH 5.0 was observed (from pH-optimum of 4.5 for the native enzyme, rPvCel5A-wt and N19A mutant). The N19A mutation led to a notable decrease in the specific activity against carboxymethylcellulose and barley β-glucan (by 26% and 12% relative to the rPvCel5A-wt), while the N42A and N194A mutants displayed 12-13% and 32-35% increase in the activities. Similar effects of the mutations were observed in prolonged hydrolysis of β-glucan and milled aspen wood by rPvCel5A forms in the presence of purified β-glucosidase.

The aim of the research was to study the effect of a number of coordination compounds of stanum and germanium (compounds 1‒8) as modifiers of activity of peptidases and α-galactosidases. The coordination compounds with the same type structure of were investigated as enzymes effectors. Two types of complexes: 1) [M(H2O)6][Ge(НCitr)2]4H2O (M = Mg(1), Mn(2), Co(3), Ni(4), Zn(5)), containing biscitrate-stanate anion ([Ge(НCitr)2]2-), and 2) [M(H2O)6][Sn(НCitr)2]4H2O (M = Mg(6), Co(7), Ni(8)), containing biscitratostanate anion and various hexaaquacations ([M(H2O)6]2+, М= Mg, Mn, Co, Ni, Zn) were studied. It is shown that the compound 6 which is a biscitratostanate complex containing magnesium ions as metal, can be used for stimulation on 20‒25% of collagenase activity of B. thuringiensis var. israelensis IMV B-7465 peptidase 1 and peptidase 2. Compound 1 (biscitrate-stanate complex containing magnesium ions as metal) and 7 (biscitratostanate complex containing cobalt ions as metal) and compound 6 in a concentration of 0.001% are able to increase elastolytic activity of peptidase 1 on 55‒58%. However compound 7 has shown the greatest activating effect. It increased the elastolytic activity of peptidase 2 on 100‒140% (for both tested concentrations). This indicates that the compound 7 can further be used as of peptidase 2 elastolytic activity effector. In the study of effect of the considered coordination compounds on the activity of α-galactosidase of Penicillium canescens, Cladosporium cladosporioides and Aspergillus niger was found that when using a number of complexes (1‒2 and 4‒8), there is a slight increase on 12‒20% of enzyme activity of P. canescens, and the maximum effect (~20%, concentration 0.01%) was provided by complex 6.

Plant biomasses are the predominant organic material on Earth. The efficiency of biocatalytic conversion of the plant materials is determined by the cost of their biotechnological processing to valuable commercial products (organic alcohols and acids, carbohydrates and hycrocarbons). The obtained recombinant strains Penicillium canescens produce, apart from their own enzymatic complex, heterological cellulases (mutant and non-mutant cellobiohydrolase I (CBHI) and endoglucanase II (EGII) P. verruculosum ). Enzymatic agents (EA) prepared from recombinant strains P. canescens were more active to hydrolysis of crushed aspen wood. The yields of glucose and reducing sugars after 24–72 hour hydrolysis under the action of EA prepared from the recombinant strains were higher by на 48–52 % and 60–64 %, respectively, than under the action of EA prepared from the initial strainrecipient. Thus, introduction of site-specific mutations N45A and N194A for partial inhibition of the surface glycosilation led to a considerable increase in the yields of target CBHI and EGII.

This paper reports the first results on obtaining an enzyme preparation that might be promising for the simultaneous decontamination of plant feeds contaminated with a polyketide fusariotoxin, zearalenone (ZEN), and enhancing the availability of their nutritional components. A novel ZEN-specific lactonohydrolase (ZHD) was expressed in a Penicillium canescens strain PCA-10 that was developed previously as a producer of different hydrolytic enzymes for feed biorefinery. The recombinant ZHD secreted by transformed fungal clones into culture liquid was shown to remove the toxin from model solutions, and was able to decontaminate wheat grain artificially infected with a zearalenone-producing Fusarium culmorum. The dynamics of ZEN degradation depending on the temperature and pH of the incubation media was investigated, and the optimal values of these parameters (pH 8.5, 30 &deg, C) for the ZHD-containing enzyme preparation (PR-ZHD) were determined. Under these conditions, the 3 h co-incubation of ZEN and PR-ZHD resulted in a complete removal of the toxin from the model solutions, while the PR-ZHD addition (8 mg/g of dried grain) to flour samples prepared from the infected ZEN-polluted grain (about 16 &micro, g/g) completely decontaminated the samples after an overnight exposure.

Worldwide, 463 million people are affected by diabetes of which the majority is diagnosed with Type 2 Diabetes (T2D). T2D can ultimately lead to retinopathy, nephropathy, nerve damage, and amputation of the lower extremities. α-Glucosidase, responsible for converting starch to monosaccharides, is a key therapeutic target for the management of T2D. However, due to substantial side effects of currently marketed drugs, there is an urgent need for the discovery of new α-glucosidase inhibitors. In our ongoing efforts to identify novel α-glucosidase inhibitors from Nature, we are investigating the potential of endophytic filamentous fungi as sustainable sources of hits and/or leads for future antihyperglycemic drugs. Here we report one previously unreported xanthone (5) and two known xanthones (7 and 11) as α-glucosidase inhibitors, isolated from an endophytic Penicillium canescens, recovered from fruits of Juniperus polycarpos. The three xanthones 5, 7, and 11 showed inhibitory activities against α-glucosidase with IC50 values of 38.80 ± 1.01 μM, 32.32 ± 1.01 μM, and 75.20 ± 1.02 μM, respectively. Further pharmacological characterization revealed a mixed-mode inhibition for 5, a competitive inhibition for 7, while 11 acted as a non-competitive inhibitor.

Balıkesir Üniversitesi, Fen Bilimleri Enstitüsü, Biyoloji Ana Bilim Dalı, Günümüzde sentetik boyaların kullanılmasının çevre üzerinde zarar verici etkilerinin olduğu ve insanlarda görülen alerjik astım, toksijenik ve karsinojenik hastalıklara sebep olduğu bilinmektedir. Bu nedenle farklı kaynaklardan (bitkiler, böcekler, likenler, bakteriler ve mineraller gibi) insanlara ve çevreye zarar vermeyen doğal pigment arayışı tüm dünyada devam etmektedir. Funguslardan pigment elde etmeye yönelik çalışmalar oldukça yenidir. Bu çalışmada Manisa ili Akhisar İlçesi, Musaca köyünden toplanan toprak örneklerinin mikrobiyotası araştırılmıştır. Çalışmada topraklardan mikrofungus izole edilmesinde “Toprağı Sulandırma Metodu” kullanılmıştır. Bu metotla 17 toprak örneğinden elde edilen izolatlar arasından moleküler yöntemlerle teşhis edilen P. purpurogenum ve P. canescens türleri pigment üretici olarak belirlenmiştir. Pigment üretiminde farklı besiyerlerinde (SDA, MEA, PDA, ve YEA) farklı sıcaklıkta (25, 28, 30 °C)’ de ve farklı pH’ larda (1, 3, 5, 7, 9, 11, 13) 15 gün boyunca inkübe edilerek pigment elde edildi. En yüksek pigment üretimi 5.5 pH’ ta ve 28 °C sıcaklıkta görüldü. Pigment ekstresi için ethanol (w/v: 1/1) çözücüsü kullanıldı ve 72 saat 26 °C’ de 160 rpm çalkalandı ve sonra sırasıyla 45 µm ve 20 µm filtreden geçirildi. Ekstre liyofilize edilerek kırmızı ve sarı pigmentler elde edildi. Pigment çözeltisinin (500 mg/mL) farklı pH, sıcaklık değerleri ve farklı çözücüler ile renk karakterizasyonu yapıldı. Çalışma sonucunda pigment üretimini etkileyen koşullar belirlendi., It is now known that the use of synthetic dyes has harmful effects on the environment and causes allergic asthma, toxigenic and carcinogenic diseases seen in humans. For this reason, the search for natural pigments from different sources (such as plants, insects, lichens, bacteria and minerals) that do not harm people and the environment continues all over the world. Studies to obtain pigments from fungi are quite new. This study was carried out in order to determine the microfungal flora of soils in Manisa ,Akhisar Musaca. In this study , the isolation of microfungi from soil samples into culture media was performed via "soil dilution plate method". , the production of pigments were investigated with strains isolated on soil samples and identified by molecular methods. Pigment production in different mediums (SDA, MEA, PDA, and YEA), different temperatures (25, 28, 30 °C) and different pH's (5, 7, 9) the pigment was incubated for 15 days. The best pigment production was observed at pH 5.5, temperature 28 °C. Pigment extraction was rinsed with ethanol (w/v: 1/1) solvent for 72 hours at 160 rpm at 26 °C and filtered through 20 μm. The soluble was evaporated and which was then lyophilized to a red and yellow pigment. Pigment solution (500 mg / mL) was color characterized by different pH, temperature values and different solvents. By means of our study, pigmnet production were determined in the extracts of the isolates and the results were discussed., Bu tez çalışması Balıkesir Üniversitesi Bilimsel Araştırma Projeleri birimi tarafından 2015-227 nolu proje ile desteklenmiştir.

Two xylanases (XylA and XylE) of glycoside hydrolase family 10 are isolated from an enzyme preparation produced by Penicillium canescens fungi. The kinetics of the hydrolysis of glucuronoxylan and arabinoxylan by the purified enzymes and the effect of proteinaceous (XIP-like) inhibitors from rye on the viscometric activity of the xylanases are studied. XylA provides a more complete conversion of glucuronoxylan than XylE, while XylE is more effective in the arabinoxylan hydrolysis. Unlike XylA, XylE is resistant to the proteinaceous inhibitors from rye—this property is rarely found in the enzymes of family 10. Thus, XylE is a promising enzyme for use as a cereal feed additive, while XylA may potentially be used for the biobleaching of cellulose from hardwoods, which contain glucuronoxylan as one of the major components.

Cellulases are the main components of enzyme complexes used in biotransformation processes of plant raw materials into valuable commercial products. Endoglucanase II (EG II) from the Penicillium verruculosum fungus was cloned into Penicillium canescens. The homogeneous recombinant EGII form is isolated and its properties are studied in comparison with the native enzyme. The N-glycosylation sites and the structure of the N-linked glycans are been determined using mass spectrometry. The biochemical and catalytic properties, as well as the N-glycosylation type of the obtained recombinant EGII form, appear to be close to the native enzyme. At the two potential N-glycosylation sites (N42 and N194) of both forms of the enzyme, N-linked high mannose glycans (or their enzymatic “trimming” products) according to the general formula (Man)1–9(GlcNAc)2 are detected. No glycosylation is found at the third potential site (N19).

Recombinant strains of Penicillium canescens producing homologous pectin lyase A and heterologous endo- 1,5-α-arabinase A and endo- 1,4-α-polygalacturonase, as well as enzymes of the host strain (α-L-arabinofuranosidases, xylanases, and others), were obtained by genetic engineering. The enzyme preparations (EPs) obtained from the cultural medium of recombinant P. canescens strains efficiently hydrolyzed raw plant material with a high content of pectin compounds. It was shown that the yield of reducing sugars and arabinose increased 16 and 22% in comparison with the control EP based on the host strain when one of the obtained EPs was used for beet pulp hydrolysis. It was established that the most active EP consisted of pectin lyase (10%), endo-1,5-arabinase (26%), α-L-arabinofuranosidase and arabinoxylan-arabinofuranohydrolase (12%), and xylanase (10%). The activities of pectin lyase, polygalacturonase, and arabinase of the EP in reactions with various substrates were determined. The specificity, pH and T-optima, and thermal stability of the homogenous recombinant endo- 1,5-α-arabinase were investigated. The kinetic parameters (K(m), K(cat)) of the linear arabinan hydrolysis were determined.

Two glucoamylases, a recombinant enzyme from Penicillium verruculosum (PvGla) heterologously expressed in Penicillium canescens RN3-11-7 (niaD-) strain and a native glucoamylase from Myceliophthora thermophila (MtGla), were purified and their properties were studied. MtGla displayed 2-5-fold higher specific activities against soluble starch, amylose and amylopectin than PvGla. MtGla also provided higher glucose yields in extended hydrolysis of the polymeric substrates. Analysis of 3D model structures of the intact PvGla and MtGla, which were built using the 2vn7.pdb crystal structure of the intact Trichoderma reesei glucoamylase (TrGla) as a template, showed that the reason for lower hydrolytic performance of PvGla in comparison to MtGla may be less strong interactions between the enzyme domains as well as a longer (by 17 residues) linker in the first enzyme.

Meroterpenoids are a class of secondary metabolites that are produced from polyketide and terpenoid precursors. 15-Deoxyoxalicine B (1) belongs to one structural group consisting of a unique pyridinyl-α-pyrone polyketide subunit and a diterpenoid subunit connected through a characteristic asymmetric spiro carbon atom. An understanding of the genes involved in the biosynthesis of this class of compounds should provide a means to facilitate engineering of second-generation molecules and increasing production of first-generation compounds. We found that the filamentous fungus Penicillium canescens produces 15-deoxyoxalicine B (1). Using targeted gene deletions, we have identified a cluster of 12 responsible contiguous genes. This gene cluster includes one polyketide synthase gene which we have designated olcA. Chemical analysis of wild-type and gene deletion mutant extracts enabled us to isolate and characterize 7 additional metabolites that are either intermediates or shunt products of the biosynthetic pathway. Two of the compounds identified have not been reported previously. Our data have allowed us to propose a biosynthetic pathway for 15-deoxyoxalicine B (1).

In order to investigate factors affecting the thermostability of GH10 xylanase A from Penicillium canescens (PcXylA) and to obtain its more stable variant, the wild-type (wt) enzyme and its mutant forms, carrying single amino acid substitutions, were cloned and expressed in Penicillium verruculosum B1-537 (niaD-) auxotrophic strain under the control of the cbh1 gene promoter. The recombinant PcXylA-wt and I6V, I6L, L18F, N77D, Y125R, H191R, S246P, A293P mutants were successfully expressed and purified for characterization. The mutations did not affect the enzyme specific activity against xylan from wheat as well as its pH-optimum of activity. One mutant (L18F) displayed a higher thermostability relative to the wild-type enzyme; its half-life time at 50–60 °C was 2–2.5–fold longer than that for the PcXylA-wt, and the melting temperature was 60.0 and 56.1 °C, respectively. Most of other mutations led to decrease in the enzyme thermostability. This study, together with data of other researchers, suggests that multiple mutations should be introduced into GH10 xylanases in order to dramatically improve their stability.

In this study, the antimicrobial potential of three fungal endophytes from leaves of Olea europaea L. was evaluated and the host plant extract effect in the antimicrobial activity was examined. The volatile compounds produced by endophytes were identified by GC/MS and further correlated with the antimicrobial activity. In potato dextrose agar, both Penicillium commune and Penicillium canescens were the most effective inhibiting Gram-positive and -negative bacteria (up to 2.7-fold compared to 30 µg/mL chloramphenicol), whereas Alternaria alternata was most effective inhibiting yeasts (up to 8.0-fold compared to 25 μg/mL fluconazole). The presence of aqueous leaf extract in culture medium showed to induce or repress the antimicrobial activity, depending on the endophytic species. In the next step, various organic extracts from both A. alternata mycelium and cultured broth we re prepared; being ethyl acetate extracts displayed the widest spectrum of anti-microorganisms at a minimum inhibitory concentration ≤0.095 mg/mL. The volatile composition of the fungi that displayed the highest (A. alternata) and the lowest (P. canescens) antimicrobial activity against yeasts revealed the presence of six volatiles, being the most abundant components (3-methyl-1-butanol and phenylethyl alcohol) ascribed with antimicrobial potentialities. Overall the results highlighted for the first time the antimicrobial potential of endophytic fungi from O. europaea and the possibility to be exploited for their antimicrobial agents. Graphical Abstract: [Figure not available: see fulltext.] This work is funded by FEDER funds through COMPETE (Programa Operacional Factores de Competitividade) and by national funds by FCT (Fundação para a Ciência e a Tecnologia) in the framework of the project “EndoBio—Isolation and screening of endophytic fungi for biological control of olive against Colletotrichum acutatum and Verticillium dahliae” (PTDC/ AGR-PRO/4354/2012). info:eu-repo/semantics/publishedVersion

The effect of the glycosylation inhibitors (tunicamycin and 2-deoxy-D-glucose) on the activity, stabili­ty and production of fungal glycosidases has been studied. It was shown that inhibition of N-glycosylation sites did not affect the secretion of Aspergillus niger α-galactosidase, however reduced yield of Cladosporium cladosporioides and Penicillium canescens α-galactosidases. Changes in the level of O-glycosylation resulted in a significant reduction in the activity and stability of α-galactosidases of all three producers tested. Activity of the modified enzymes was significantly lower than that of the native ones, and was 2.6 and 0.33 U/mg for A. niger α-galactosidase, 3.3 and 32.5 U/mg for C. cladosporioides α-galactosidase, 11.66 and 31.1 U/mg for P. canescens α-galactosidase, respectively. A. niger α-galactosidase completely lost activity during purification and storage. The decrease of thermal stability at 55 °C by 20% was shown for C. cladosporioides and P. canescens α-galactosidases. It was also noted that O-deglycosylation led to a decrease in resistance of these enzymes to the action of proteases.

The properties of transgenic aspen (Populus tremula) clones carrying the recombinant gene of xyloglucanase sp-Xeg from Penicillium canescens have been analyzed. Complex modifications were revealed both in the composition of the wood and in the plant phenotype. Biometric analysis showed that shoot dimensions increased by 24.8%, 25% and 26% in the PtXIV-Xeg1a, PtXVXeg1a and PtXVXeg1b lines, respectively. The number of internodes in some transgenic clones also increased. Modifications in rhizogenesis have been shown for the first time in the plants with the recombinant gene of xyloglucanase: in vitro rooting efficiency exceeded the control value in 13 out of 25 lines. Maximum rooting efficiency was observed in the PtXVXeg1a line (3.2-fold higher than in the control). A reliable increase in the root system mass (by 20% to 52%) under greenhouse conditions was observed for 8 out of 25 clones. A lower pentosan content in the wood was shown for all lines. The data on xyloglucanase activity and pentosan content generally correlated with phenotypic modifications.

Structurally simple 1-thio-β-D-glucopyranosides were synthesized and tested as potential inhibitors toward several fungal glycosidases from Aspergillus oryzae and Penicillium canescens. Significant selective inhibition was observed for α- and β-glucosidases, while a weak to moderate activation for α- and β-galactosidases.

Under the deacetylation of fungal endophyte Penicillium canescens , which was isolated from pigeon pea, a novel and highly efficient biotransformation method of astragalosides to astragaloside IV in Radix Astragali was investigated. After single factor tests of the biotransformation procedure, the optimum biotransformation conditions were confirmed as the liquid solid ratio 20:1, the biotransformation temperature 30 °C, time 36 h and pH 7, respectively. Final content of astragaloside IV in Radix Astragali reached 7.66 ± 0.44 mg/g, which was 5.51-fold to that of untreated one and contents of astragaloside I and astragaloside II significantly decreased. The immobilized Ca-alginate gel beads with P. canescens could be reused at least for 13 runs. This is the first report that fungal endophyte was applied for the biotransformation of astragalosides to astragaloside IV in Radix Astragali and this novel high-efficiency biotransformation method will be an alternative to enhance the content of astragaloside IV in Radix Astragali in commercial process.

Using MALDI-TOF mass spectrometry (MS) peptide fingerprinting procedure followed by the analysis of MS data with the GlycoMod tool from the ExPASy proteomic site, N-glycosylation of two GH51 and GH54 family α-l-arabinofuranosidases (Abf51A and Abf54A) from Penicillium canescens was studied. Variable N-linked glycans were identified at five out of eight potential N-glycosylation sites in the Abf51A and one out of three potential N-glycosylation sites in the Abf54A. The discriminated glycans represented high-mannose oligosaccharides (Man)x(GlcNAc)2 with a number of Man residues up to 7 or the products of sequential enzymatic trimming of a high-mannose glycan with α-mannosidases and β-N-acetylhexosaminidases. The Abf54A peptide, containing the Asn254 glycosylation site, and one peptide from the Abf51A, containing the Asn163 glycosylation site, were found to exist not only in glycosylated, but also in a native non-modified form.

The exudates of three fungal species (Aspergillus niger, Fusarium sambucinum and Penicillium canescens) have been tested for their effect on the algal population and diversity of El-Ibrahemia Canal. It has been found that the exudates of F. sambucinum was stimulatory for the algal population, whereas that of A. niger was inhibitory. Penicillium canscens exudate, in comparison, displayed the weakest effect. The results imply a great variation in the effectiveness of different types of fungal exudates on the different algal taxa. Chlorella fusca has been studied intensively, because it was the only chlorophycean species that survived and tolerated all applied concentration of the exudates of the three studied fungi. The growth of C. fusca has been enhanced by F. sambucinum exudates, but not by that of A. niger. The effect of fungal exudates on some metabolic components of C. fusca is discussed.

Analysis of the properties of transgenic aspen clones with recombinant gene xyloglucanase sp-Xeg from fungi Penicillium canescens showed the presence of complex modifications both in the wood and the phenotype of plants. Biometric analysis revealed an increase in the height of transgenic plants as compared to control plants. Increasing in the height of the shoot of 24.8%, 25% and 26% was observed for lines PtXIVXeg1a, PtXVXeg1a, PtXVXeg1b, respectively. Also there was an increase in the number of internodes in some transgenic clones. For the first time we showed the change in plants rhizogenesis with the recombinant gene xyloglucanase. In 10 of the 25 lines the rooting efficiency in vitro exceeded the control value. The maximum value of the rhizogenesis was fixed for line PtXVXeg1a (2.5 times higher than the control value). The mass of the root system for 6 of the 25 clones in the greenhouse was higher by 20% than the control value. The pentosan content decrease was also detected in all wood samples of transgenic plants. The obtained data of xyloglucanase activity and pentosan content generally correlated with phenotypic modifications.

Plant xyloglucans play an important role in the processes of cell wall extension, determine their mechanical properties, thus affecting growth and morphology of individual cells and whole organs. Being one of the main components of hemicellulose, xyloglucans play a particular physiological role in woody plants. To study xyloglucan physiological role, transgenic aspen (Populus tremula L.) plants with a recombinant sp-Xeg gene from the fungus Penicillium canescens were produced. Constitutive expression of this gene in the heterologous surrounding was confirmed by RT-PCR method. The analysis of protein extracts from the leaves of greenhouse-grown plants and microshoots grown in vitro showed activation of xylogluconase in transgenic lines. The strongest activation (1.6-fold) was observed in the leaf extracts (clone PtXVXeg1b) and in vitro microshoots (clone PtXVXeg1c). In transgenic plants, the relative content of pentosans in the wood was declined. In control plants (Pt genotype), it was equal to 148 mg/g dry wt, whereas in tested clones (PtXVXeg1a, PtXVXeg1b, and PtXVXeg1c), it varied from 100 to 140 mg/g dry wt. The strongest decrease (by 31%) in the content of pentosans was observed for the line PtXVXeg1c; the content was equal to 102.1 ± 1.5 mg/g dry wt. A comparative analysis of leaf morphology revealed an increase in the length of petiole and a decrease in the length of the main vein in transgenic lines. In control plants, the ratio of the petiole length to the length of the main vein was equal to 0.49, whereas in transgenic plants, it varied from 0.51 to 0.66. A significant increase of this index was observed in 12 from 14 transgenic lines.

Extracellular beta-D-glucosidase was isolated in a homogeneous state from the Penicillium canescens marine fungus. According to SDS-electrophoresis, the molecular weight of the enzyme was 64 kDa and the maximal activity was observed at pH 5.2 and 70 degrees C. Glucosidase catalyzed the hydrolysis of beta-glycosidic bonds both in glycosides and in glucose disaccharides and had transglycosylation activity. The enzyme can be used for the deglycosylation of natural glycosides and in enzymatic synthesis of new carbon-containing compounds.