Publications by authors named "Jaana Kuuskeri"

Laccases are multi-copper oxidases that use molecular oxygen as the electron acceptor to oxidize phenolic and indirectly also non-phenolic substrates by mechanisms involving radicals. Due to their eco-friendliness and broad substrate specificity, laccases span a wide range of biotechnological applications. We have heterologously expressed a laccase from the coprophilic basidiomycete (Lcc9) in the methylotrophic yeast .

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Fungal laccases are attracting enzymes for sustainable valorization of biorefinery lignins. To improve the lignin oxidation capacity of two previously characterized laccase isoenzymes from the white-rot fungus Obba rivulosa, we mutated their substrate-binding site at T1. As a result, the pH optimum of the recombinantly produced laccase variant rOrLcc2-D206N shifted by three units towards neutral pH.

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The kraft lignin's low molecular weight and too high hydroxyl content hinder its application in bio-based carbon fibers. In this study, we were able to polymerize kraft lignin and reduce the amount of hydroxyl groups by incubating it with the white-rot fungus . Enzymatic radical oxidation reactions were hypothesized to induce condensation of lignin, which increased the amount of aromatic rings connected by carbon-carbon bonds.

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Background: The white rot fungus Phlebia radiata, a type species of the genus Phlebia, is an efficient decomposer of plant cell wall polysaccharides, modifier of softwood and hardwood lignin, and is able to produce ethanol from various waste lignocellulose substrates. Thus, P. radiata is a promising organism for biotechnological applications aiming at sustainable utilization of plant biomass.

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Feruloyl esterases (FAEs) are accessory enzymes for plant biomass degradation, which catalyse hydrolysis of carboxylic ester linkages between hydroxycinnamic acids and plant cell-wall carbohydrates. They are a diverse group of enzymes evolved from, e.g.

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Fomitopsis pinicola is a species of Polyporales frequently encountered in Nordic temperate and boreal forests. In nature, the fungus causes destructive brown rot in wood, colonizing tree trunks often occupied by other Basidiomycota species. We mimicked these species-species interactions by introducing F.

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Ethanol production from non-pretreated lignocellulose was carried out in a consolidated bioprocess with wood-decay fungi of phlebioid Polyporales. Ethanol production was attempted on glucose, spruce wood sawdust and waste core board. Substantial quantities of ethanol were achieved, and isolate Phlebia radiata 0043 produced 5.

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Background: The white-rot Agaricomycetes species Phlebia radiata is an efficient wood-decaying fungus degrading all wood components, including cellulose, hemicellulose, and lignin. We cultivated P. radiata in solid state cultures on spruce wood, and extended the experiment to 6 weeks to gain more knowledge on the time-scale dynamics of protein expression upon growth and wood decay.

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Background: The fungal genus Phlebia consists of a number of species that are significant in wood decay. Biotechnological potential of a few species for enzyme production and degradation of lignin and pollutants has been previously studied, when most of the species of this genus are unknown. Therefore, we carried out a wider study on biochemistry and systematics of Phlebia species.

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Mitochondria are eukaryotic organelles supporting individual life-style via generation of proton motive force and cellular energy, and indispensable metabolic pathways. As part of genome sequencing of the white rot Basidiomycota species Phlebia radiata, we first assembled its mitochondrial genome (mtDNA). So far, the 156 348 bp mtDNA is the second largest described for fungi, and of considerable size among eukaryotes.

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The lignin-degrading, biopulping white-rot fungus Physisporinus rivulosus secretes several laccases of distinct features such as thermostability, extremely low pH optima and thermal activation for oxidation of phenolic substrates. Here we describe the cloning, heterologous expression and structural and enzymatic characterisation of two previously undescribed P. rivulosus laccases.

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