The Experts below are selected from a list of 249 Experts worldwide ranked by ideXlab platform
Hirofumi Hirai - One of the best experts on this subject based on the ideXlab platform.
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Self-fusion and fusion cell isolation of transformants derived from white rot fungus Phanerochaete sordida YK-624 by simple visual method.
Journal of bioscience and bioengineering, 2019Co-Authors: Toshio Mori, Hirokazu Kawagishi, Tomoki Sumiya, Ojiro Kondo, Hirofumi HiraiAbstract:In order to develop a simple method for crossing two transformants, we first attempted to elucidate the fusion type (self-compatibility or -incompatible) of Phanerochaete sordida YK-624. Two transformants expressing green or red fluorescent protein derived from an Auxotrophic Mutant were constructed. Each recombinant protein fluoresced by expression as a fused protein with glyceraldehyde-3-phosphate dehydrogenase. On co-culture of both transformants, a number of sequential hyphal cells emitting dual fluorescence were formed at the contact areas of both hyphae. Some of the single cells isolated as protoplasts and chlamydospore from the co-cultures also expressed these fluorescent proteins. These results suggest that P. sordida YK-624 possesses a self-compatible fusion system. In addition, transformant strains with different fluorescence derived from this fungus can readily undergo self-fusion and nuclear interchange events by confrontational and mixed cultivation, and we developed a simple method that allows fused cells to be isolated as chlamydospores.
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Effects of Homologous Expression of 1,4-Benzoquinone Reductase and Homogentisate 1,2-Dioxygenase Genes on Wood Decay in Hyper-Lignin-Degrading Fungus Phanerochaete sordida YK-624
Current Microbiology, 2016Co-Authors: Toshio Mori, Hirokazu Kawagishi, Genki Koyama, Hirofumi HiraiAbstract:We investigated the function of 1,4-benzoquinone reductase (BQR)- and homogentisate 1,2-dioxygenase (HGD)-like genes in wood degradation by Phanerochaete sordida YK-624, which exhibits high ligninolytic activity and selectivity. We determined homologous expression in the genomic and cDNA sequences of BQR- and HGD-like genes in P. sordida YK-624 ( PsBQR and PsHGD ). Both genes shared high homology (≥90 % amino acid sequence similarity) with the corresponding genes in Phanerochaete chrysosporium . These genes were co-transformed with a reporter gene into an uracil Auxotrophic Mutant of P. sordida YK-624. The PsBQR and PsHGD co-transformants exhibited lower holocellulolytic activity and higher ligninolytic selectivity than the control transformants. In liquid culture with vanillin, both co-transformants significantly accelerated vanillin degradation. Thus, we suggest that the rapid metabolism of low-molecular weight lignin fragments, due to the homologous expression of BQR- and HGD-like genes, affects quinone redox cycling to produce hydroxyl radicals, thereby decreasing holocellulose degradation and increasing ligninolytic selectivity.
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Improvement of manganese peroxidase production by the hyper lignin-degrading fungus Phanerochaete sordida YK-624 by recombinant expression of the 5-aminolevulinic acid synthase gene.
Current microbiology, 2013Co-Authors: Hirofumi Hirai, Kenta Misumi, Tomohiro Suzuki, Hirokazu KawagishiAbstract:The manganese peroxidase (MnP) gene (mnp4) promoter of Phanerochaete sordida YK-624 was used to drive expression of 5-aminolevulinic acid synthase (als), which is a key heme biosynthesis enzyme. The expression plasmid pMnP4pro-als was transformed into P. sordida YK-624 uracil Auxotrophic Mutant UV-64, and 14 recombinant als expressing-transformants were generated. Average cumulative MnP activities in the transformants were 1.18-fold higher than that of control transformants. In particular, transformants A-14 and A-61 showed significantly higher MnP activity (approximately 2.8-fold) than wild type. RT-PCR analysis indicated that the increased MnP activity was caused by elevated recombinant als expression. These results suggest that the production of MnP is improved by high expression of als.
Toshio Mori - One of the best experts on this subject based on the ideXlab platform.
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Self-fusion and fusion cell isolation of transformants derived from white rot fungus Phanerochaete sordida YK-624 by simple visual method.
Journal of bioscience and bioengineering, 2019Co-Authors: Toshio Mori, Hirokazu Kawagishi, Tomoki Sumiya, Ojiro Kondo, Hirofumi HiraiAbstract:In order to develop a simple method for crossing two transformants, we first attempted to elucidate the fusion type (self-compatibility or -incompatible) of Phanerochaete sordida YK-624. Two transformants expressing green or red fluorescent protein derived from an Auxotrophic Mutant were constructed. Each recombinant protein fluoresced by expression as a fused protein with glyceraldehyde-3-phosphate dehydrogenase. On co-culture of both transformants, a number of sequential hyphal cells emitting dual fluorescence were formed at the contact areas of both hyphae. Some of the single cells isolated as protoplasts and chlamydospore from the co-cultures also expressed these fluorescent proteins. These results suggest that P. sordida YK-624 possesses a self-compatible fusion system. In addition, transformant strains with different fluorescence derived from this fungus can readily undergo self-fusion and nuclear interchange events by confrontational and mixed cultivation, and we developed a simple method that allows fused cells to be isolated as chlamydospores.
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Effects of Homologous Expression of 1,4-Benzoquinone Reductase and Homogentisate 1,2-Dioxygenase Genes on Wood Decay in Hyper-Lignin-Degrading Fungus Phanerochaete sordida YK-624
Current Microbiology, 2016Co-Authors: Toshio Mori, Hirokazu Kawagishi, Genki Koyama, Hirofumi HiraiAbstract:We investigated the function of 1,4-benzoquinone reductase (BQR)- and homogentisate 1,2-dioxygenase (HGD)-like genes in wood degradation by Phanerochaete sordida YK-624, which exhibits high ligninolytic activity and selectivity. We determined homologous expression in the genomic and cDNA sequences of BQR- and HGD-like genes in P. sordida YK-624 ( PsBQR and PsHGD ). Both genes shared high homology (≥90 % amino acid sequence similarity) with the corresponding genes in Phanerochaete chrysosporium . These genes were co-transformed with a reporter gene into an uracil Auxotrophic Mutant of P. sordida YK-624. The PsBQR and PsHGD co-transformants exhibited lower holocellulolytic activity and higher ligninolytic selectivity than the control transformants. In liquid culture with vanillin, both co-transformants significantly accelerated vanillin degradation. Thus, we suggest that the rapid metabolism of low-molecular weight lignin fragments, due to the homologous expression of BQR- and HGD-like genes, affects quinone redox cycling to produce hydroxyl radicals, thereby decreasing holocellulose degradation and increasing ligninolytic selectivity.
Zhu-hui Kang - One of the best experts on this subject based on the ideXlab platform.
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Feasibility of biohydrogen production from tofu wastewater with glutamine Auxotrophic Mutant of Rhodobacter sphaeroides
Renewable Energy, 2010Co-Authors: G. H. Zheng, L. Wang, Zhu-hui KangAbstract:Abstract NH4+, which is normally the integrant in organic wastewater, such as Tofu wastewater, is an inhibitor to hydrogen production by anoxygenic phototrophic bacterium. In order to release inhibition of NH4+ to biohydrogen generation by Rhodobacter sphaeroides, a glutamine Auxotrophic Mutant R. sphaeroides TJ-0803 was obtained by mutagenizing with ethyl methane sulfonate. The Mutant could generate biohydrogen efficiently in the medium with high NH4+ concentration, because the inhibition of NH4+ to nitrogenase was released. Under suitable conditions, TJ-0803 could effectively produce biohydrogen from tofu wastewater, which commonly containing 50–60 mg L−1 NH4+, and the generation rate was increased by more than 100% compared with that from wild-type R. sphaeroides.
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Biohydrogen Production from Tofu Wastewater with Glutamine Auxotrophic Mutant of Rhodobacter sphaeroides
AIP Conference Proceedings, 2008Co-Authors: G. H. Zheng, L. Wang, Zhu-hui Kang, Y. F. Qian, Q. Zhou, H. G. ZhuAbstract:Hydrogen production from organic wastewater by photo‐bacteria has been attracted more attention, not only because hydrogen is a clean energy, but also because it can be a process for organic wastewater pre‐treatment. However NH4+, which normally is the integrant in organic wastewater, is the inhibitor to hydrogen production with photo‐bacteria. In this study, the NH4+ effect on biohydrogen generation and nitrogenase activity of anoxygenic phototrophic bacteria‐Rhodobacter sphaeroides was studied. Biohydrogen generation with wild‐type R. sphaeroides was found to be more sensitive to NH4+ due to the obvious inhibition of NH4+ to its nitrogenase. For avoiding inhibition of NH4+ to biohydrogen generation of R. sphaeroides, a glutamine Auxotrophic Mutant R. sphaeroides AR‐3 was obtained by EMS treatment. The Mutant could generate biohydrogen efficiently in the medium with higher NH4+ concentration. Under suitable conditions, AR‐3 produced biohydrogen from tofu wastewater with an average generation rate of 14.2...
Hirokazu Kawagishi - One of the best experts on this subject based on the ideXlab platform.
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Self-fusion and fusion cell isolation of transformants derived from white rot fungus Phanerochaete sordida YK-624 by simple visual method.
Journal of bioscience and bioengineering, 2019Co-Authors: Toshio Mori, Hirokazu Kawagishi, Tomoki Sumiya, Ojiro Kondo, Hirofumi HiraiAbstract:In order to develop a simple method for crossing two transformants, we first attempted to elucidate the fusion type (self-compatibility or -incompatible) of Phanerochaete sordida YK-624. Two transformants expressing green or red fluorescent protein derived from an Auxotrophic Mutant were constructed. Each recombinant protein fluoresced by expression as a fused protein with glyceraldehyde-3-phosphate dehydrogenase. On co-culture of both transformants, a number of sequential hyphal cells emitting dual fluorescence were formed at the contact areas of both hyphae. Some of the single cells isolated as protoplasts and chlamydospore from the co-cultures also expressed these fluorescent proteins. These results suggest that P. sordida YK-624 possesses a self-compatible fusion system. In addition, transformant strains with different fluorescence derived from this fungus can readily undergo self-fusion and nuclear interchange events by confrontational and mixed cultivation, and we developed a simple method that allows fused cells to be isolated as chlamydospores.
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Effects of Homologous Expression of 1,4-Benzoquinone Reductase and Homogentisate 1,2-Dioxygenase Genes on Wood Decay in Hyper-Lignin-Degrading Fungus Phanerochaete sordida YK-624
Current Microbiology, 2016Co-Authors: Toshio Mori, Hirokazu Kawagishi, Genki Koyama, Hirofumi HiraiAbstract:We investigated the function of 1,4-benzoquinone reductase (BQR)- and homogentisate 1,2-dioxygenase (HGD)-like genes in wood degradation by Phanerochaete sordida YK-624, which exhibits high ligninolytic activity and selectivity. We determined homologous expression in the genomic and cDNA sequences of BQR- and HGD-like genes in P. sordida YK-624 ( PsBQR and PsHGD ). Both genes shared high homology (≥90 % amino acid sequence similarity) with the corresponding genes in Phanerochaete chrysosporium . These genes were co-transformed with a reporter gene into an uracil Auxotrophic Mutant of P. sordida YK-624. The PsBQR and PsHGD co-transformants exhibited lower holocellulolytic activity and higher ligninolytic selectivity than the control transformants. In liquid culture with vanillin, both co-transformants significantly accelerated vanillin degradation. Thus, we suggest that the rapid metabolism of low-molecular weight lignin fragments, due to the homologous expression of BQR- and HGD-like genes, affects quinone redox cycling to produce hydroxyl radicals, thereby decreasing holocellulose degradation and increasing ligninolytic selectivity.
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Improvement of manganese peroxidase production by the hyper lignin-degrading fungus Phanerochaete sordida YK-624 by recombinant expression of the 5-aminolevulinic acid synthase gene.
Current microbiology, 2013Co-Authors: Hirofumi Hirai, Kenta Misumi, Tomohiro Suzuki, Hirokazu KawagishiAbstract:The manganese peroxidase (MnP) gene (mnp4) promoter of Phanerochaete sordida YK-624 was used to drive expression of 5-aminolevulinic acid synthase (als), which is a key heme biosynthesis enzyme. The expression plasmid pMnP4pro-als was transformed into P. sordida YK-624 uracil Auxotrophic Mutant UV-64, and 14 recombinant als expressing-transformants were generated. Average cumulative MnP activities in the transformants were 1.18-fold higher than that of control transformants. In particular, transformants A-14 and A-61 showed significantly higher MnP activity (approximately 2.8-fold) than wild type. RT-PCR analysis indicated that the increased MnP activity was caused by elevated recombinant als expression. These results suggest that the production of MnP is improved by high expression of als.
Yuzuru Iimura - One of the best experts on this subject based on the ideXlab platform.
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Development of an integrative DNA transformation system for the yeast Hansenula anomala
Journal of Fermentation and Bioengineering, 2002Co-Authors: Tomoo Ogata, Yuzuru Iimura, Yasushi Okumura, Takaji ObataAbstract:Abstract A host-vector system for the yeast Hansenula anomala was developed. The system was based on an Auxotrophic Mutant host of H. anomala which was defective in orotidine-5′-phosphate decarboxylase (ODCase) activity. The H. anomala ODCase-negative Mutant strains ( ura3 strains) were isolated based on 5-fluoroorotic acid (5-FOA) resistance. A plasmid vector containing the H. anomala URA3 gene was used for transformation. Using this plasmid, all of the H. anomala ura3 strains tested could be transformed to Ura + phenotypes. In all of Ura + transformants, the introduced plasmid was integrated into the chromosomal URA3 locus by homologous recombination. The Ura + phenotype of the transformants was stably maintained after nonselective growth.
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Transformation system for a wastewater treatment yeast, Hansenula fabianii J640: isolation of the orotidine-5'-phosphate decarboxylase gene (URA3) and uracil Auxotrophic Mutants
Applied Microbiology and Biotechnology, 1997Co-Authors: Miyoshi Kato, Haruyuki Iefuji, K. Miyake, Yuzuru IimuraAbstract:A transformation system for Hansenula fabianii J640, a commonly used wastewater treatment yeast, was constructed. As a host cell, a uracil Auxotrophic Mutant designated as H. fabianii J640 u-1, which was confirmed to have a mutation at the locus of the gene for orotidine-5′-phosphate (OMP) decarboxylase (URA3), was obtained by positive selection using 5-fluoroorotic acid. A plasmid named pHFura3, which includes a 795-bp open-reading frame of the OMP decarboxylase H. fabianii, was obtained by complementation of the Escherichia colipyrF Mutant. pHFura3 could transform H. fabianii J640 u-1 by a non-homologous and frequently multicopy integration into the host genomic DNA.