13 results on '"Glazunova, Olga"'
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2. The subatomic resolution study of laccase inhibition by chloride and fluoride anions using single-crystal serial crystallography: insights into the enzymatic reaction mechanism.
- Author
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Polyakov KM, Gavryushov S, Fedorova TV, Glazunova OA, and Popov AN
- Subjects
- Basidiomycota enzymology, Catalytic Domain, Crystallography, X-Ray methods, Ligands, Models, Molecular, Oxidation-Reduction, Oxygen metabolism, Protein Conformation, Single Molecule Imaging methods, Chlorides metabolism, Copper metabolism, Fluorides metabolism, Laccase chemistry
- Abstract
Laccases are enzymes that catalyze the oxidation of a wide range of organic and inorganic substrates accompanied by the reduction of molecular oxygen to water. Here, a subatomic resolution X-ray crystallographic study of the mechanism of inhibition of the laccase from the basidiomycete fungus Steccherinum murashkinskyi by chloride and fluoride ions is presented. Three series of X-ray diffraction data sets were collected with increasing doses of absorbed X-ray radiation from a native S. murashkinskyi laccase crystal and from crystals of complexes of the laccase with chloride and fluoride ions. The data for the native laccase crystal confirmed the previously deduced enzymatic mechanism of molecular oxygen reduction. The structures of the complexes allowed the localization of chloride and fluoride ions in the channel near the T2 copper ion. These ions replace the oxygen ligand of the T2 copper ion in this channel and can play the role of this ligand in the enzymatic reaction. As follows from analysis of the structures from the increasing dose series, the inhibition of laccases by chloride and fluoride anions can be explained by the fact that the binding of these negatively charged ions at the position of the oxygen ligand of the T2 copper ion impedes the reduction of the T2 copper ion.
- Published
- 2019
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3. Laccases with Variable Properties from Different Strains of Steccherinum ochraceum : Does Glycosylation Matter?
- Author
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Glazunova OA, Moiseenko KV, Kamenihina IA, Isaykina TU, Yaropolov AI, and Fedorova TV
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- Amino Acid Sequence, Fungal Proteins chemistry, Glycosylation, Laccase chemistry, Models, Molecular, Polyporales chemistry, Polyporales metabolism, Protein Isoforms chemistry, Protein Isoforms metabolism, Substrate Specificity, Fungal Proteins metabolism, Laccase metabolism, Polyporales enzymology
- Abstract
Laccases are blue multi-copper oxidases with an extensive number of actual and potential industrial applications. It is known that laccases from different fungal strains may vary in properties; however, the reason of this remains unclear. In the current study we have isolated and characterized seven laccases from different strains of Steccherinum ochraceum obtained from regions of central Russia. Although all seven laccases had the same primary sequences, there was a little variation in their molecular weights and thermostabilities. Moreover, statistically significant differences in laccases' catalytic parameters of oxidation of phenolic substrates and ABTS were observed. After the deglycosylation of four selected laccases by Endo H and PNGase F, their affinities to pyrocatechol and ABTS became the same, suggesting a substantial role of N -linked glycosylation in moderation of enzymatic properties of laccases.
- Published
- 2019
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4. Structure-function study of two new middle-redox potential laccases from basidiomycetes Antrodiella faginea and Steccherinum murashkinskyi.
- Author
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Glazunova OA, Polyakov KM, Moiseenko KV, Kurzeev SA, and Fedorova TV
- Subjects
- Catalysis, Catalytic Domain, Copper chemistry, Crystallography, X-Ray, Ligands, Models, Molecular, Oxidation-Reduction, Oxygen chemistry, Structure-Activity Relationship, Water chemistry, Basidiomycota enzymology, Laccase chemistry, Protein Conformation
- Abstract
Laccases are multicopper oxidases that catalyze oxidation of a wide range of organic and inorganic substrates accompanied by the reduction of dioxygen to water. The physicochemical and catalytic properties of two new fungal laccases from basidiomycetes Antrodiella faginea (AfL) and Steccherinum murashkinskyi (SmL) with middle redox potential of the T1 copper site were studied. The X-ray structures of AfL and SmL were solved at 1.75 Å and 0.95 Å, respectively. The oxidized state of copper ions in the active site was observed in AfL structure, while the mixture of oxidized and reduced states was observed in SmL structure. These oxidized and reduced states relate to the position of copper ions, their coordination, and nature and position of oxygen ligands. Comparative analysis of the T1 site environment of laccases with known structure allowed us to highlight the six types of the secondary coordination sphere of the T1 copper. The solvent accessible surface area of the conservative region of the secondary coordination sphere of the T1 copper correlates with its the redox potential. It was shown that the laccase classification by the structure of the T1 copper secondary coordination sphere is in agreement to ecophysiological behavior of laccase producing fungi., (Copyright © 2018. Published by Elsevier B.V.)
- Published
- 2018
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5. White-rot basidiomycetes Junghuhnia nitida and Steccherinum bourdotii: Oxidative potential and laccase properties in comparison with Trametes hirsuta and Coriolopsis caperata.
- Author
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Glazunova OA, Shakhova NV, Psurtseva NV, Moiseenko KV, Kleimenov SY, and Fedorova TV
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- Coriolaceae enzymology, Enzyme Stability, Laccase genetics, Laccase metabolism, Oxidation-Reduction, Polyporales enzymology, Temperature, Trametes enzymology, Basidiomycota enzymology, Laccase chemistry, Oxidative Stress genetics
- Abstract
White-rot basidiomycetes from the poorly studied residual polyporoid clade of Polyporales order Junghuhnia nitida (Pers.) Ryvarden and Steccherinum bourdotii Saliba & A. David grow as secondary xylotrohps on well decomposed woody materials. The main objective of the current study was to compare oxidative potential, growth, production of oxidative enzymes and laccase properties of J. nitida and S. bourdotii with that of typical primary xylotrohps Trametes hirsuta (Wulfen) Lloyd and Coriolopsis caperata (Berk.) Murrill, belonging to the core polyporoid clade. For the first time we report species J. nitida and S. bourdotii as active laccase producers. New laccases from J. nitida and S. bourdotii were purified and characterized. They had an identical molecular weight of 63 kDa and isoelectric points of 3.4 and 3.1, respectively. However, the redox potential of the T1 copper site for both J. nitida (610 mV) and S. bourdotii (640 mV) laccases was lower than those for T. hirsuta and C. caperata laccases. The new laccases showed higher temperature optima and better thermal stability than T. hirsuta and C. caperata laccases. Their half-lives were more than 40 min at 70 °C. The laccases from J. nitida and S. bourdotii showed higher affinity to syringyl-type phenolic compounds than T. hirsuta and C. caperata laccases. The oxidative potential of studied fungi as well as the properties of their laccases are discussed in terms of the fungal life-style., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2018
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6. Orchestration of the expression of the laccase multigene family in white-rot basidiomycete Trametes hirsuta 072: Evidences of transcription level subfunctionalization.
- Author
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Moiseenko KV, Vasina DV, Farukshina KT, Savinova OS, Glazunova OA, Fedorova TV, and Tyazhelova TV
- Subjects
- Carbon metabolism, Culture Media chemistry, Enzyme Activators metabolism, Laccase genetics, Multigene Family, Nitrogen Compounds metabolism, Trametes growth & development, Trametes metabolism, Gene Expression Regulation, Fungal, Laccase biosynthesis, Trametes enzymology, Trametes genetics, Transcription, Genetic
- Abstract
Laccase (benzenediol:oxygen oxidoreductase, EC 1.10.3.2) is an enzyme that has been studied for over 100 y and is present in virtually all fungi. As increasing numbers of fungal genomes have been sequenced, it has become apparent that the laccase genes in white-rot fungi commonly form multigene families consisting of many nonallelic genes. Although a number of reports focussing on laccase gene expression in different fungal species were published over the decades, the fundamental questions of why fungi need such a redundant array of genes and how they manage this array to perform biological function(s) remain far from answered. In this article, we present a comprehensive study of the transcription of the whole Trametes hirsuta laccase multigene family under different conditions, including exposure to different nutritional factors such as nitrogen sources (organic and inorganic) and concentrations of nitrogen and carbon in the culture medium; in different growth phases (lag phase and stationary phase); and in the presence of different inducer agents (water-soluble lignin, bromocresol green dye, p-coumaric acid, ferulic acid, guaiacol, vanillin, veratryl alcohol, vanillic acid and syringic acid). Our findings are discussed in the context of the evolution of the laccase multigene family, and the presence of transcription-level subfunctionalization is highlighted., (Copyright © 2018 British Mycological Society. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2018
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7. The Trametes hirsuta 072 laccase multigene family: Genes identification and transcriptional analysis under copper ions induction.
- Author
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Vasina DV, Mustafaev ON, Moiseenko KV, Sadovskaya NS, Glazunova OA, Tyurin АА, Fedorova TV, Pavlov AR, Tyazhelova TV, Goldenkova-Pavlova IV, and Koroleva OV
- Subjects
- Fungal Proteins genetics, Gene Expression Regulation, Fungal drug effects, Gene Expression Regulation, Fungal genetics, Laccase classification, Laccase genetics, Multigene Family genetics, Phylogeny, Trametes drug effects, Trametes genetics, Copper pharmacology, Fungal Proteins metabolism, Laccase metabolism, Trametes enzymology
- Abstract
Laccases, blue copper-containing oxidases, ≿ an play an important role in a variety of natural processes. The majority of fungal laccases are encoded by multigene families that express closely related proteins with distinct functions. Currently, only the properties of major gene products of the fungal laccase families have been described. Our study is focused on identification and characterization of laccase genes, which are transcribed in basidiomycete Trametes hirsuta 072, an efficient lignin degrader, in a liquid medium, both without and with induction of laccase transcription by copper ions. We carried out production of cDNA libraries from total fungal RNA, followed by suppression subtractive hybridization and mirror orientation selection procedures, and then used Next Generation Sequencing to identify low abundance and differentially expressed laccase transcripts. This approach resulted in description of five laccase genes of the fungal family, which, according to the phylogenetic analysis, belong to distinct clusters within the Trametes genus. Further analysis established similarity of physical, chemical, and catalytic properties between laccases inside each cluster. Structural modeling suggested importance of the sequence differences in the clusters for laccase substrate specificity and catalytic efficiency. The implications of the laccase variations for the fungal physiology are discussed., (Copyright © 2015 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.)
- Published
- 2015
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8. Elucidation of the crystal structure of Coriolopsis caperata laccase: restoration of the structure and activity of the native enzyme from the T2-depleted form by copper ions.
- Author
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Glazunova OA, Polyakov KM, Fedorova TV, Dorovatovskii PV, and Koroleva OV
- Subjects
- Catalytic Domain, Copper metabolism, Coriolaceae chemistry, Crystallography, X-Ray, Laccase metabolism, Models, Molecular, Oxidation-Reduction, Protein Conformation, Copper chemistry, Coriolaceae enzymology, Laccase chemistry
- Abstract
Laccases are members of a large family of multicopper oxidases that catalyze the oxidation of a wide range of organic and inorganic substrates accompanied by the reduction of dioxygen to water. A new laccase was isolated from the basidiomycete Coriolopsis caperata strain 0677 and its amino-acid sequence was determined. According to its physicochemical properties and spectroscopic features, the laccase from C. caperata is a high redox-potential blue laccase. Attempts to crystallize the native enzyme were unsuccessful. The copper type 2-depleted (T2D) laccase was prepared and crystallized. The structure of T2D laccase from C. caperata was solved at 1.6 Å resolution, and attempts to reconstruct the T2 copper centre were performed using Cu(+) and Cu(2+) ions. The structure of T2D+Cu(+) laccase was solved at 1.89 Å resolution. It was shown that the T2D+Cu(+) laccase structure contained four copper ions in the active site. Reconstruction could not be achieved when the T2D laccase crystals were treated with CuSO4.
- Published
- 2015
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9. Comparative Analysis of Peniophora lycii and Trametes hirsuta Exoproteomes Demonstrates "Shades of Gray" in the Concept of White-Rotting Fungi.
- Author
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Shabaev, Alexander V., Moiseenko, Konstantin V., Glazunova, Olga A., Savinova, Olga S., and Fedorova, Tatyana V.
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LACCASE ,EXTRACELLULAR enzymes ,HYDROLASES ,HEMICELLULOSE ,FUNGI ,WOOD ,COMPARATIVE studies - Abstract
White-rot basidiomycete fungi are a unique group of organisms that evolved an unprecedented arsenal of extracellular enzymes for an efficient degradation of all components of wood such as cellulose, hemicelluloses and lignin. The exoproteomes of white-rot fungi represent a natural enzymatic toolbox for white biotechnology. Currently, only exoproteomes of a narrow taxonomic group of white-rot fungi—fungi belonging to the Polyporales order—are extensively studied. In this article, two white-rot fungi, Peniophora lycii LE-BIN 2142 from the Russulales order and Trametes hirsuta LE-BIN 072 from the Polyporales order, were compared and contrasted in terms of their enzymatic machinery used for degradation of different types of wood substrates—alder, birch and pine sawdust. Our findings suggested that the studied fungi use extremely different enzymatic systems for the degradation of carbohydrates and lignin. While T. hirsuta LE-BIN 072 behaved as a typical white-rot fungus, P. lycii LE-BIN 2142 demonstrated substantial peculiarities. Instead of using cellulolytic and hemicellulolytic hydrolytic enzymes, P. lycii LE-BIN 2142 primarily relies on oxidative polysaccharide-degrading enzymes such as LPMO and GMC oxidoreductase. Moreover, exoproteomes of P. lycii LE-BIN 2142 completely lacked ligninolytic peroxidases, a well-known marker of white-rot fungi, but instead contained several laccase isozymes and previously uncharacterized FAD-binding domain-containing proteins. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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10. Purification and Characterization of Two Novel Laccases from Peniophora lycii.
- Author
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Glazunova, Olga A., Moiseenko, Konstantin V., Savinova, Olga S., and Fedorova, Tatyana V.
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BASIDIOMYCETES , *LACCASE , *PENIOPHORA , *ISOENZYMES , *NUCLEOTIDE sequence - Abstract
Although, currently, more than 100 laccases have been purified from basidiomycete fungi, the majority of these laccases were obtained from fungi of the Polyporales order, and only scarce data are available about the laccases from other fungi. In this article, laccase production by the white-rot basidiomycete fungus Peniophora lycii, belonging to the Russulales order, was investigated. It was shown that, under copper induction, this fungus secreted three different laccase isozymes. Two laccase isozymes--Lac5 and LacA--were purified and their corresponding nucleotide sequences were determined. Both purified laccases were relatively thermostable with periods of half-life at 70 °C of 10 and 8 min for Lac5 and LacA, respectively. The laccases demonstrated the highest activity toward ABTS (97 U·mg-1 for Lac5 and 121 U·mg-1 for LacA at pH 4.5); Lac5 demonstrated the lowest activity toward 2,6-DMP (2.5 U·mg-1 at pH 4.5), while LacA demonstrated this towards gallic acid (1.4 U·mg-1 at pH 4.5). Both Lac5 and LacA were able to efficiently decolorize such dyes as RBBR and Bromcresol Green. Additionally, phylogenetic relationships among laccases of Peniophora spp. were reconstructed, and groups of orthologous genes were determined. Based on these groups, all currently available data about laccases of Peniophora spp. were systematized. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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11. Fungal Laccases: The Forefront of Enzymes for Sustainability.
- Author
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Loi, Martina, Glazunova, Olga, Fedorova, Tatyana, Logrieco, Antonio F., and Mulè, Giuseppina
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ENZYMES , *LACCASE , *INDUSTRIAL applications , *LIGNINS , *BIOACTIVE compounds - Abstract
Enzymatic catalysis is one of the main pillars of sustainability for industrial production. Enzyme application allows minimization of the use of toxic solvents and to valorize the agro-industrial residues through reuse. In addition, they are safe and energy efficient. Nonetheless, their use in biotechnological processes is still hindered by the cost, stability, and low rate of recycling and reuse. Among the many industrial enzymes, fungal laccases (LCs) are perfect candidates to serve as a biotechnological tool as they are outstanding, versatile catalytic oxidants, only requiring molecular oxygen to function. LCs are able to degrade phenolic components of lignin, allowing them to efficiently reuse the lignocellulosic biomass for the production of enzymes, bioactive compounds, or clean energy, while minimizing the use of chemicals. Therefore, this review aims to give an overview of fungal LC, a promising green and sustainable enzyme, its mechanism of action, advantages, disadvantages, and solutions for its use as a tool to reduce the environmental and economic impact of industrial processes with a particular insight on the reuse of agro-wastes. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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12. Fungal Adaptation to the Advanced Stages of Wood Decomposition: Insights from the Steccherinum ochraceum.
- Author
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Moiseenko, Konstantin V., Glazunova, Olga A., Shakhova, Natalia V., Savinova, Olga S., Vasina, Daria V., Tyazhelova, Tatiana V., Psurtseva, Nadezhda V., and Fedorova, Tatiana V.
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STAGE adaptations ,WOOD decay ,LACCASE ,CLIMATIC zones ,ECOLOGICAL niche ,GENE families - Abstract
Steccherinum ochraceum is a white rot basidiomycete with wide ecological amplitude. It occurs in different regions of Russia and throughout the world, occupying different climatic zones. S. ochraceum colonizes stumps, trunks, and branches of various deciduous (seldom coniferous) trees. As a secondary colonizing fungus, S. ochraceum is mainly observed at the late decay stages. Here, we present the de novo assembly and annotation of the genome of S. ochraceum, LE-BIN 3174. This is the 8th published genome of fungus from the residual polyporoid clade and the first from the Steccherinaceae family. The obtained genome provides a first glimpse into the genetic and enzymatic mechanisms governing adaptation of S. ochraceum to an ecological niche of pre-degraded wood. It is proposed that increased number of carbohydrate-active enzymes (CAZymes) belonging to the AA superfamily and decreased number of CAZymes belonging to the GH superfamily reflects substrate preferences of S. ochraceum. This proposition is further substantiated by the results of the biochemical plate tests and exoproteomic study, which demonstrates that S. ochraceum assumes the intermediate position between typical primary colonizing fungi and litter decomposers or humus saprotrophs. Phylogenetic analysis of S. ochraceum laccase and class II peroxidase genes revealed the distinct evolutional origin of these genes in the Steccherinaceae family. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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13. Catalytic Efficiency of Basidiomycete Laccases: Redox Potential versus Substrate-Binding Pocket Structure.
- Author
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Glazunova, Olga A., Trushkin, Nikita A., Moiseenko, Konstantin V., Filimonov, Ivan S., and Fedorova, Tatyana V.
- Subjects
- *
BASIDIOMYCETES , *LACCASE , *PHENOLS , *OXIDASES , *OXIDOREDUCTASES - Abstract
Laccases are copper-containing oxidases that catalyze a one-electron abstraction from various phenolic and non-phenolic compounds with concomitant reduction of molecular oxygen to water. It is well-known that laccases from various sources have different substrate specificities, but it is not completely clear what exactly provides these differences. The purpose of this work was to study the features of the substrate specificity of four laccases from basidiomycete fungi
Trametes hirsuta ,Coriolopsis caperata ,Antrodiella faginea , andSteccherinum murashkinskyi , which have different redox potentials of the T1 copper center and a different structure of substrate-binding pockets. Enzyme activity toward 20 monophenolic substances and 4 phenolic dyes was measured spectrophotometrically. The kinetic parameters of oxidation of four lignans and lignan-like substrates were determined by monitoring of the oxygen consumption. For the oxidation of the high redox potential (>700 mV) monophenolic substrates and almost all large substrates, such as phenolic dyes and lignans, the redox potential difference between the enzyme and the substrate (ΔE ) played the defining role. For the low redox potential monophenolic substrates, ΔE did not directly influence the laccase activity. Also, in the special cases, the structure of the large substrates, such as dyes and lignans, as well as some structural features of the laccases (flexibility of the substrate-binding pocket loops and some amino acid residues in the key positions) affected the resulting catalytic efficiency. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
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