1
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Senoo S, Shintani T, Nieda S, Shintani T, Kariyama M, Gomi K. Construction of self-cloning Aspergillus oryzae strains with high production of multiple biomass-degrading enzymes on solid-state culture. J Biosci Bioeng 2024; 137:204-210. [PMID: 38242757 DOI: 10.1016/j.jbiosc.2023.12.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 12/06/2023] [Accepted: 12/07/2023] [Indexed: 01/21/2024]
Abstract
Filamentous fungi produce numerous industrially important enzymes. Among them, Aspergillus oryzae-derived enzymes are widely used in various fermentation applications. In this study, we constructed self-cloning strains that overproduce multiple biomass-degrading enzymes under the control of a strong promoter of α-amylase-coding gene (amyB) using the industrial strain A. oryzae AOK11. Two strains (strains 2-4 and 3-26) were introduced with different combinations of genes encoding xylanase (xynG1), phytase (phyA), pectin lyase (pelA), and polygalacturonase (pgaB). These strains had at least one copy of each enzyme gene derived from the expression cassette in the genome. The transcription levels of enzyme-coding genes introduced were more than 100-fold higher than those in the parent strain. Reflecting the high transcription levels, the activities of the enzymes derived from the expression cassettes of these two strains were significantly higher than those of the parent strain in both liquid and solid-state cultures. Even in ventilated solid-state cultures that were scaled up using mechanical equipment for practical applications, the two strains showed significantly higher enzyme activity than the parent strain. These results indicate that these strains constructed using a safe self-cloning technique represent industrially valuable practical strains that can be used in the food and livestock industries.
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Affiliation(s)
- Satoko Senoo
- Graduate School of Agricultural Science, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai 980-8572, Japan; Process Development Division, Fujiwara Techno-Art Co., Ltd., 2827-3 Tomiyoshi, Kita-ku, Okayama 701-1133, Japan.
| | - Tomoko Shintani
- Graduate School of Agricultural Science, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai 980-8572, Japan
| | - Shoko Nieda
- Process Development Division, Fujiwara Techno-Art Co., Ltd., 2827-3 Tomiyoshi, Kita-ku, Okayama 701-1133, Japan
| | - Takahiro Shintani
- Graduate School of Agricultural Science, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai 980-8572, Japan
| | - Masahiro Kariyama
- Process Development Division, Fujiwara Techno-Art Co., Ltd., 2827-3 Tomiyoshi, Kita-ku, Okayama 701-1133, Japan
| | - Katsuya Gomi
- Graduate School of Agricultural Science, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai 980-8572, Japan
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2
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Ichikawa T, Tanaka M, Watanabe T, Zhan S, Watanabe A, Shintani T, Gomi K. Crucial role of the intracellular α-glucosidase MalT in the activation of the transcription factor AmyR essential for amylolytic gene expression in Aspergillus oryzae. Biosci Biotechnol Biochem 2021; 85:2076-2083. [PMID: 34245563 DOI: 10.1093/bbb/zbab125] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Accepted: 06/29/2021] [Indexed: 11/12/2022]
Abstract
We examined the role of the intracellular α-glucosidase gene malT, which is part of the maltose-utilizing cluster (MAL cluster) together with malR and malP, in amylolytic gene expression in Aspergillus oryzae. malT disruption severely affected fungal growth on medium containing maltose or starch. Furthermore, the transcription level of the α-amylase gene was significantly reduced by malT disruption. Given that the transcription factor AmyR responsible for amylolytic gene expression is activated by isomaltose converted from maltose incorporated into the cells, MalT may have transglycosylation activity that converts maltose to isomaltose. Indeed, transglycosylated products such as isomaltose/maltotriose and panose were generated from the substrate maltose by MalT purified from a malT-overexpressing strain. The results of this study, taken together, suggests that MalT plays a pivotal role in AmyR activation via its transglycosylation activity that converts maltose to the physiological inducer isomaltose.
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Affiliation(s)
- Takanori Ichikawa
- Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai 980-8572, Japan
| | - Mizuki Tanaka
- Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai 980-8572, Japan
| | - Takayasu Watanabe
- Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai 980-8572, Japan
| | - Sitong Zhan
- Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai 980-8572, Japan
| | - Akira Watanabe
- Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai 980-8572, Japan
| | - Takahiro Shintani
- Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai 980-8572, Japan
| | - Katsuya Gomi
- Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai 980-8572, Japan.,Laboratory of Fermentation Microbiology, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai 980-8572, Japan
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3
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Expression profiles of amylolytic genes in AmyR and CreA transcription factor deletion mutants of the black koji mold Aspergillus luchuensis. J Biosci Bioeng 2021; 132:321-326. [PMID: 34176737 DOI: 10.1016/j.jbiosc.2021.06.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 06/03/2021] [Accepted: 06/09/2021] [Indexed: 11/22/2022]
Abstract
The black koji mold, Aspergillus luchuensis, which belongs to Aspergillus section Nigri, is used for the production of traditional Japanese spirits (shochu) mainly in the southern districts of Japan. This mold is known to produce amylolytic enzymes essential for shochu production; however, mechanisms regulating amylolytic gene expression in A. luchuensis have not been studied in as much detail as those in the yellow koji mold, Aspergillus oryzae. Here, we examined the gene expression profiles of deletion mutants of transcription factors orthologous to A. oryzae AmyR and CreA in A. luchuensis. A. luchuensis produces acid-unstable (AmyA) and acid-stable (AsaA) α-amylases. AmyA production and amyA gene expression were not influenced by amyR or creA deletion, indicating that amyA was constitutively expressed. In contrast, asaA gene expression was significantly down- and upregulated upon deletion of amyR and creA, respectively. Furthermore, the glaA and agdA genes (encoding glucoamylase and α-glucosidase, respectively) showed expression profiles similar to those of asaA. Thus, genes that play pivotal roles in starch saccharification, asaA, glaA, and agdA, were found to be regulated by AmyR and CreA. Moreover, despite previous reports on AsaA being only produced in solid-state culture, deletion of the ortholog of A. oryzae flbC, which is involved in the expression of the solid-state culture-specific genes, did not affect AsaA α-amylase activity, suggesting that FlbC was not associated with asaA expression.
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4
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Tanaka M, Gomi K. Induction and Repression of Hydrolase Genes in Aspergillus oryzae. Front Microbiol 2021; 12:677603. [PMID: 34108952 PMCID: PMC8180590 DOI: 10.3389/fmicb.2021.677603] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 04/26/2021] [Indexed: 11/13/2022] Open
Abstract
The filamentous fungus Aspergillus oryzae, also known as yellow koji mold, produces high levels of hydrolases such as amylolytic and proteolytic enzymes. This property of producing large amounts of hydrolases is one of the reasons why A. oryzae has been used in the production of traditional Japanese fermented foods and beverages. A wide variety of hydrolases produced by A. oryzae have been used in the food industry. The expression of hydrolase genes is induced by the presence of certain substrates, and various transcription factors that regulate such expression have been identified. In contrast, in the presence of glucose, the expression of the glycosyl hydrolase gene is generally repressed by carbon catabolite repression (CCR), which is mediated by the transcription factor CreA and ubiquitination/deubiquitination factors. In this review, we present the current knowledge on the regulation of hydrolase gene expression, including CCR, in A. oryzae.
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Affiliation(s)
- Mizuki Tanaka
- Biomolecular Engineering Laboratory, School of Food and Nutritional Science, University of Shizuoka, Shizuoka, Japan
| | - Katsuya Gomi
- Laboratory of Fermentation Microbiology, Graduate School of Agricultural Science, Tohoku University, Sendai, Japan
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5
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Morita Y, Kikumatsu F, Higuchi Y, Katakura Y, Takegawa K. Characterization and functional analysis of ERAD-related AAA+ ATPase Cdc48 in Aspergillus oryzae. Fungal Biol 2020; 124:801-813. [PMID: 32883430 DOI: 10.1016/j.funbio.2020.06.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 06/25/2020] [Accepted: 06/27/2020] [Indexed: 12/21/2022]
Abstract
Aspergillus oryzae can secrete large amounts of enzymes. However, the production of abundant secretory proteins triggers the unfolded protein response (UPR) in the endoplasmic reticulum (ER), and it is not clear how ER-associated protein degradation (ERAD) contributes to bulk protein production in A. oryzae. Here we identified AoCdc48, the sole A. oryzae ortholog of Saccharomyces cerevisiae AAA+ ATPase Cdc48, a component of the ERAD machinery. We found that AoCdc48 localizes in both nuclei and cytoplasm. Generation of an Aocdc48 conditional mutant showed that Aocdc48 repression leads to reduced cell growth and aberrant hyphal morphology. When Aocdc48-repressed cells were cultured on starch-containing plates, the α-amylase-encoding gene amyB was about 1.3-fold higher expressed. Indeed, a halo produced by secreted amylase was seen on potato starch-containing plates even when there was almost no growth under Aocdc48 repression. Fluorescence microscopy revealed that although AmyB seemed to be secreted, various organelle distributions were aberrant in Aocdc48-repressed cells. We found that D1 AAA domain is crucial for cell viability. Finally, we show that Aocdc48-overexpression also causes defects of cell growth, colonial morphology and conidial formation. Collectively, our results suggest that AoCdc48 is essential for growth and organelle distribution but dispensable for amylase secretion.
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Affiliation(s)
- Yuki Morita
- Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, 744 Motooka, Fukuoka, 819-0395, Japan
| | - Futa Kikumatsu
- Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, 744 Motooka, Fukuoka, 819-0395, Japan
| | - Yujiro Higuchi
- Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, 744 Motooka, Fukuoka, 819-0395, Japan.
| | - Yoshinori Katakura
- Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, 744 Motooka, Fukuoka, 819-0395, Japan
| | - Kaoru Takegawa
- Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, 744 Motooka, Fukuoka, 819-0395, Japan
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6
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Miyazawa K, Yoshimi A, Abe K. The mechanisms of hyphal pellet formation mediated by polysaccharides, α-1,3-glucan and galactosaminogalactan, in Aspergillus species. Fungal Biol Biotechnol 2020; 7:10. [PMID: 32626592 PMCID: PMC7329490 DOI: 10.1186/s40694-020-00101-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 06/12/2020] [Indexed: 01/01/2023] Open
Abstract
Filamentous fungi are widely used for production of enzymes and chemicals, and are industrially cultivated both in liquid and solid cultures. Submerged culture is often used as liquid culture for filamentous fungi. In submerged culture, filamentous fungi show diverse macromorphology such as hyphal pellets and dispersed hyphae depending on culture conditions and genetic backgrounds of fungal strains. Although the macromorphology greatly affects the productivity of submerged cultures, the specific cellular components needed for hyphal aggregation after conidial germination have not been characterized. Recently we reported that the primary cell wall polysaccharide α-1,3-glucan and the extracellular polysaccharide galactosaminogalactan (GAG) contribute to hyphal aggregation in Aspergillus oryzae, and that a strain deficient in both α-1,3-glucan and GAG shows dispersed hyphae in liquid culture. In this review, we summarize our current understanding of the contribution of chemical properties of α-1,3-glucan and GAG to hyphal aggregation. Various ascomycetes and basidiomycetes have α-1,3-glucan synthase gene(s). In addition, some Pezizomycotina fungi, including species used in the fermentation industry, also have GAG biosynthetic genes. We also review here the known mechanisms of biosynthesis of α-1,3-glucan and GAG. Regulation of the biosynthesis of the two polysaccharides could be a potential way of controlling formation of hyphal pellets.
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Affiliation(s)
- Ken Miyazawa
- Laboratory of Applied Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki-Aoba, Aoba-ku, Sendai, 980-8572 Japan
| | - Akira Yoshimi
- Laboratory of Environmental Interface Technology of Filamentous Fungi, Graduate School of Agriculture, Kyoto University, Oiwake-cho, Kitashirakawa, Sakyo-ku, Kyoto, 606-8502 Japan.,ABE-project, New Industry Creation Hatchery Center, Tohoku University, 6-6-10 Aramaki-Aoba, Aoba-ku, Sendai, 980-8579 Japan
| | - Keietsu Abe
- Laboratory of Applied Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki-Aoba, Aoba-ku, Sendai, 980-8572 Japan.,ABE-project, New Industry Creation Hatchery Center, Tohoku University, 6-6-10 Aramaki-Aoba, Aoba-ku, Sendai, 980-8579 Japan.,Laboratory of Microbial Resources, Department of Microbial Biotechnology, Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki-Aoba, Aoba-ku, Sendai, 980-8572 Japan
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7
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Ichikawa K, Shiono Y, Shintani T, Watanabe A, Kanzaki H, Gomi K, Koseki T. Efficient production of recombinant tannase in Aspergillus oryzae using an improved glucoamylase gene promoter. J Biosci Bioeng 2019; 129:150-154. [PMID: 31492608 DOI: 10.1016/j.jbiosc.2019.08.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 08/05/2019] [Accepted: 08/05/2019] [Indexed: 12/20/2022]
Abstract
A tannase-encoding gene, AotanB, from Aspergillus oryzae RIB40 was overexpressed in A. oryzae AOK11 niaD-deficient mutant derived from an industrial strain under the control of an improved glucoamylase gene promoter PglaA142. The recombinant tannase, designated as rAoTanBO, was produced efficiently as an active extracellular enzyme. Purified rAoTanBO showed a smeared band with a molecular mass of approximately 80-100 kDa on sodium dodecyl sulfate polyacrylamide gel electrophoresis. The rAoTanBO had a molecular mass of 65 kDa, after treatment with endo-β-N-acetylglucosaminidase H. Purified rAoTanBO exhibited maximum activity at 30-35°C and pH 6.0. The tannase activity of purified rAoTanBO towards natural and artificial substrates was 2-8 folds higher than that of the recombinant enzyme produced by Pichia pastoris, designated as rAoTanBP. N-terminus of the mature rAoTanBP had six more amino acids than the N-terminus of the mature rAoTanBO. Kinetic analyses showed that rAoTanBO had higher catalytic efficiency (kcat/Km) than rAoTanBP. rAoTanBO was stable up to 60°C and higher thermostability than rAoTanBP. N-linked oligosaccharides had no effect on the activity and stability of rAoTanBO and rAoTanBP.
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Affiliation(s)
- Kyotaro Ichikawa
- Department of Food, Life and Environmental Sciences, Faculty of Agriculture, Yamagata University, 1-23 Wakaba-machi, Tsuruoka 997-8555, Japan
| | - Yoshihito Shiono
- Department of Food, Life and Environmental Sciences, Faculty of Agriculture, Yamagata University, 1-23 Wakaba-machi, Tsuruoka 997-8555, Japan
| | - Tomoko Shintani
- Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai 980-8572, Japan
| | - Akira Watanabe
- Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai 980-8572, Japan
| | - Hiroshi Kanzaki
- Department of Biofunctional Chemistry, Graduate School of Environmental and Life Science, Okayama University, 3-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
| | - Katsuya Gomi
- Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai 980-8572, Japan
| | - Takuya Koseki
- Department of Food, Life and Environmental Sciences, Faculty of Agriculture, Yamagata University, 1-23 Wakaba-machi, Tsuruoka 997-8555, Japan.
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8
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Siriwong T, Laimeheriwa B, Aini UN, Cahyanto MN, Reungsang A, Salakkam A. Cold hydrolysis of cassava pulp and its use in simultaneous saccharification and fermentation (SSF) process for ethanol fermentation. J Biotechnol 2019; 292:57-63. [PMID: 30690096 DOI: 10.1016/j.jbiotec.2019.01.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 12/23/2018] [Accepted: 01/07/2019] [Indexed: 11/19/2022]
Abstract
The present study investigated cold hydrolysis of cassava pulp (CP) and the use of cold hydrolysis with simultaneous saccharification and fermentation (SSF) for ethanol production. Cold hydrolysis of 100 g-CP/L at 50 °C for 2 h, followed by at 30 °C for 72 h resulted in the production of 71.5 ± 1.8 g/L of reducing sugar, with a yield of 0.72 g/g-CP. A mathematical model describing the cold hydrolysis process was subsequently developed. The model proved to be applicable for other cold hydrolysis systems with satisfactory results. The sequential process of cold hydrolysis at 50 °C for 2 h, followed by SSF at 30 °C for 72 h gave 27.4 g-ethanol/L, with a productivity of 0.37 g/(L h) and a fermentation efficiency of 57.58%. Based on the results, a bioconversion process for CP to ethanol was proposed. In this process, 1 kg of ethanol could be produced from 3.65 kg of CP without any nutrient supplementation.
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Affiliation(s)
- Tanyaporn Siriwong
- Department of Biotechnology, Khon Kaen University, Khon Kaen, 40002 Thailand.
| | - Bustomi Laimeheriwa
- Department of Biotechnology, Khon Kaen University, Khon Kaen, 40002 Thailand; Department of Food and Agricultural Product Technology, Gadjah Mada University, Yogyakarta, Indonesia.
| | - Uyun Nurul Aini
- Department of Biotechnology, Khon Kaen University, Khon Kaen, 40002 Thailand; Department of Food and Agricultural Product Technology, Gadjah Mada University, Yogyakarta, Indonesia.
| | - Muhammad Nur Cahyanto
- Department of Food and Agricultural Product Technology, Gadjah Mada University, Yogyakarta, Indonesia.
| | - Alissara Reungsang
- Department of Biotechnology, Khon Kaen University, Khon Kaen, 40002 Thailand; Research Group for Development of Microbial Hydrogen Production Process from Biomass, Khon Kaen University, Khon Kaen, 40002, Thailand.
| | - Apilak Salakkam
- Department of Biotechnology, Khon Kaen University, Khon Kaen, 40002 Thailand.
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9
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Fasoyin OE, Wang B, Qiu M, Han X, Chung KR, Wang S. Carbon catabolite repression gene creA regulates morphology, aflatoxin biosynthesis and virulence in Aspergillus flavus. Fungal Genet Biol 2018; 115:41-51. [DOI: 10.1016/j.fgb.2018.04.008] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 04/08/2018] [Accepted: 04/11/2018] [Indexed: 11/24/2022]
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10
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Ichinose S, Tanaka M, Shintani T, Gomi K. Increased production of biomass-degrading enzymes by double deletion of creA and creB genes involved in carbon catabolite repression in Aspergillus oryzae. J Biosci Bioeng 2018; 125:141-147. [DOI: 10.1016/j.jbiosc.2017.08.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2017] [Revised: 08/11/2017] [Accepted: 08/29/2017] [Indexed: 10/18/2022]
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11
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Yoshimi A, Miyazawa K, Abe K. Function and Biosynthesis of Cell Wall α-1,3-Glucan in Fungi. J Fungi (Basel) 2017; 3:E63. [PMID: 29371579 PMCID: PMC5753165 DOI: 10.3390/jof3040063] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 11/10/2017] [Accepted: 11/16/2017] [Indexed: 12/30/2022] Open
Abstract
Although α-1,3-glucan is a major cell wall polysaccharide in filamentous fungi, its biological functions remain unclear, except that it acts as a virulence factor in animal and plant pathogenic fungi: it conceals cell wall β-glucan on the fungal cell surface to circumvent recognition by hosts. However, cell wall α-1,3-glucan is also present in many of non-pathogenic fungi. Recently, the universal function of α-1,3-glucan as an aggregation factor has been demonstrated. Applications of fungi with modified cell wall α-1,3-glucan in the fermentation industry and of in vitro enzymatically-synthesized α-1,3-glucan in bio-plastics have been developed. This review focuses on the recent progress in our understanding of the biological functions and biosynthetic mechanism of cell wall α-1,3-glucan in fungi. We briefly consider the history of studies on α-1,3-glucan, overview its biological functions and biosynthesis, and finally consider the industrial applications of fungi deficient in α-1,3-glucan.
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Affiliation(s)
- Akira Yoshimi
- ABE-Project, New Industry Creation Hatchery Center, Tohoku University, 6-6-10 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8579, Japan.
| | - Ken Miyazawa
- Laboratory of Applied Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-0845, Japan.
| | - Keietsu Abe
- ABE-Project, New Industry Creation Hatchery Center, Tohoku University, 6-6-10 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8579, Japan.
- Laboratory of Applied Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-0845, Japan.
- Department of Microbial Resources, Graduate School of Agricultural Science, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-0845, Japan.
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12
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Kojo T, Kadooka C, Komohara M, Onitsuka S, Tanimura M, Muroi Y, Kurazono S, Shiraishi Y, Oda K, Iwashita K, Onoue M, Okutsu K, Yoshizaki Y, Takamine K, Futagami T, Mori K, Tamaki H. Characterization of amylolytic enzyme overproducing mutant of Aspergillus luchuensis obtained by ion beam mutagenesis. J GEN APPL MICROBIOL 2017; 63:339-346. [PMID: 29046501 DOI: 10.2323/jgam.2017.02.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Aspergillus luchuensis is a kuro (black) koji fungus that has been used as a starch degrader for the awamori- and shochu-making industries in Japan. In this study, we investigated the effect of ion beam irradiation on A. luchuensis RIB2601 and obtained a high starch-degrading mutant strain U1. Strain U1 showed reduced growth rate, whereas it showed higher α-amylase, glucoamylase, and α-glucosidase activities on a mycelial mass basis than the wild type (wt) strain both on agar plates and in rice koji. In addition, strain U1 showed higher N-acetylglucosamine content in the cell wall and higher sensitivity to calcofluor white, suggesting a deficiency in cell wall composition. Interestingly, produced protein showed higher expression of acid-labile α-amylase (AmyA) and glucoamylase (GlaA) in strain U1, although real-time RT-PCR indicated no significant change in the transcription of the amyA or glaA gene. These results suggested that the high amylolytic activity of strain U1 is attributable to a high AmyA and GlaA production level, but the elevated production is not due to transcriptional regulation of the corresponding genes. Furthermore, RNA-seq analysis indicated that strain U1 shows transcriptional changes in at least 604 genes related to oxidation-reduction, transport, and glucosamine-containing compound metabolic processes, which may be involved in the deficient cell wall composition of strain U1.
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Affiliation(s)
- Toshihiro Kojo
- Education and Research Centre for Fermentation Studies, Faculty of Agriculture, Kagoshima University
| | - Chihiro Kadooka
- Education and Research Centre for Fermentation Studies, Faculty of Agriculture, Kagoshima University
| | - Marisa Komohara
- Education and Research Centre for Fermentation Studies, Faculty of Agriculture, Kagoshima University
| | - Shiori Onitsuka
- Education and Research Centre for Fermentation Studies, Faculty of Agriculture, Kagoshima University
| | - Miya Tanimura
- Education and Research Centre for Fermentation Studies, Faculty of Agriculture, Kagoshima University
| | - Yukiko Muroi
- Education and Research Centre for Fermentation Studies, Faculty of Agriculture, Kagoshima University
| | - Shugo Kurazono
- Education and Research Centre for Fermentation Studies, Faculty of Agriculture, Kagoshima University
| | - Yohei Shiraishi
- Education and Research Centre for Fermentation Studies, Faculty of Agriculture, Kagoshima University.,Bio'c, Co., Ltd
| | - Ken Oda
- National Research Institute of Brewing
| | | | - Masahira Onoue
- Natural Science Centre for Research and Education, Kagoshima University
| | - Kayu Okutsu
- Education and Research Centre for Fermentation Studies, Faculty of Agriculture, Kagoshima University
| | - Yumiko Yoshizaki
- Education and Research Centre for Fermentation Studies, Faculty of Agriculture, Kagoshima University
| | - Kazunori Takamine
- Education and Research Centre for Fermentation Studies, Faculty of Agriculture, Kagoshima University
| | - Taiki Futagami
- Education and Research Centre for Fermentation Studies, Faculty of Agriculture, Kagoshima University
| | - Kazuki Mori
- Computational Bio-Big Data Open Innovation Laboratory, National Institute of Advanced Industrial Science and Technology
| | - Hisanori Tamaki
- Education and Research Centre for Fermentation Studies, Faculty of Agriculture, Kagoshima University
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13
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Tanaka M, Hiramoto T, Tada H, Shintani T, Gomi K. Improved α-Amylase Production by Dephosphorylation Mutation of CreD, an Arrestin-Like Protein Required for Glucose-Induced Endocytosis of Maltose Permease and Carbon Catabolite Derepression in Aspergillus oryzae. Appl Environ Microbiol 2017; 83:e00592-17. [PMID: 28455339 PMCID: PMC5478985 DOI: 10.1128/aem.00592-17] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 04/24/2017] [Indexed: 12/17/2022] Open
Abstract
Aspergillusoryzae produces copious amount of amylolytic enzymes, and MalP, a major maltose permease, is required for the expression of amylase-encoding genes. The expression of these genes is strongly repressed by carbon catabolite repression (CCR) in the presence of glucose. MalP is transported from the plasma membrane to the vacuole by endocytosis, which requires the homolog of E6-AP carboxyl terminus ubiquitin ligase HulA, an ortholog of yeast Rsp5. In yeast, arrestin-like proteins mediate endocytosis as adaptors of Rsp5 and transporters. In the present study, we examined the involvement of CreD, an arrestin-like protein, in glucose-induced MalP endocytosis and CCR of amylase-encoding genes. Deletion of creD inhibited the glucose-induced endocytosis of MalP, and CreD showed physical interaction with HulA. Phosphorylation of CreD was detected by Western blotting, and two serine residues were determined as the putative phosphorylation sites. However, the phosphorylation state of the serine residues did not regulate MalP endocytosis and its interaction with HulA. Although α-amylase production was significantly repressed by creD deletion, both phosphorylation and dephosphorylation mimics of CreD had a negligible effect on α-amylase activity. Interestingly, dephosphorylation of CreD was required for CCR relief of amylase genes that was triggered by disruption of the deubiquitinating enzyme-encoding gene creB The α-amylase activity of the creB mutant was 1.6-fold higher than that of the wild type, and the dephosphorylation mimic of CreD further improved the α-amylase activity by 2.6-fold. These results indicate that a combination of the dephosphorylation mutation of CreD and creB disruption increased the production of amylolytic enzymes in A. oryzaeIMPORTANCE In eukaryotes, glucose induces carbon catabolite repression (CCR) and proteolytic degradation of plasma membrane transporters via endocytosis. Glucose-induced endocytosis of transporters is mediated by their ubiquitination, and arrestin-like proteins act as adaptors of transporters and ubiquitin ligases. In this study, we showed that CreD, an arrestin-like protein, is involved in glucose-induced endocytosis of maltose permease and carbon catabolite derepression of amylase gene expression in Aspergillusoryzae Dephosphorylation of CreD was required for CCR relief triggered by the disruption of creB, which encodes a deubiquitinating enzyme; a combination of the phosphorylation-defective mutation of CreD and creB disruption dramatically improved α-amylase production. This study shows the dual function of an arrestin-like protein and provides a novel approach for improving the production of amylolytic enzymes in A. oryzae.
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Affiliation(s)
- Mizuki Tanaka
- Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, Aramaki, Aoba-ku, Sendai, Japan
| | - Tetsuya Hiramoto
- Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, Aramaki, Aoba-ku, Sendai, Japan
| | - Hinako Tada
- Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, Aramaki, Aoba-ku, Sendai, Japan
| | - Takahiro Shintani
- Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, Aramaki, Aoba-ku, Sendai, Japan
| | - Katsuya Gomi
- Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, Aramaki, Aoba-ku, Sendai, Japan
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14
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Zhang S, Sato H, Ichinose S, Tanaka M, Miyazawa K, Yoshimi A, Abe K, Shintani T, Gomi K. Cell wall α-1,3-glucan prevents α-amylase adsorption onto fungal cell in submerged culture of Aspergillus oryzae. J Biosci Bioeng 2017; 124:47-53. [PMID: 28356219 DOI: 10.1016/j.jbiosc.2017.02.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 02/17/2017] [Indexed: 10/19/2022]
Abstract
We have previously reported that α-amylase (Taka-amylase A, TAA) activity disappears in the later stage of submerged Aspergillus oryzae culture as a result of TAA adsorption onto the cell wall. Chitin, one of the major components of the cell wall, was identified as a potential factor that facilitates TAA adsorption. However, TAA adsorption only occurred in the later stage of cultivation, although chitin was assumed to be sufficiently abundant in the cell wall regardless of the submerged culture period. This suggested the presence a factor that inhibits TAA adsorption to the cell wall in the early stage of cultivation. In the current study, we identified α-1,3-glucan as a potential inhibiting factor for TAA adsorption. We constructed single, double, and triple disruption mutants of three α-1,3-glucan synthase genes (agsA, agsB, and agsC) in A. oryzae. Growth characteristics and cell wall component analysis of these disruption strains showed that AgsB plays a major role in α-1,3-glucan synthesis. In the ΔagsB mutant, TAA was adsorbed onto the mycelium in all stages of cultivation (early and later), and the ΔagsB mutant cell walls had a significantly high capacity for TAA adsorption. Moreover, the α-1,3-glucan content of the cell wall prepared from the wild-type strain in the later stage of cultivation was markedly reduced compared with that in the early stage. These results suggest that α-1,3-glucan is a potential inhibiting factor for TAA adsorption onto the cell wall component, chitin, in the early stage of submerged culture in A. oryzae.
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Affiliation(s)
- Silai Zhang
- Laboratory of Bioindustrial Genomics, Graduate School of Agricultural Science, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai 980-0845, Japan
| | - Hiroki Sato
- Laboratory of Bioindustrial Genomics, Graduate School of Agricultural Science, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai 980-0845, Japan
| | - Sakurako Ichinose
- Laboratory of Bioindustrial Genomics, Graduate School of Agricultural Science, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai 980-0845, Japan
| | - Mizuki Tanaka
- Laboratory of Bioindustrial Genomics, Graduate School of Agricultural Science, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai 980-0845, Japan
| | - Ken Miyazawa
- Laboratory of Applied Microbiology, Graduate School of Agricultural Science, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai 980-0845, Japan
| | - Akira Yoshimi
- New Industry Creation Hatchery Center (NICHe), Tohoku University, 6-6-10 Aoba, Aramaki, Aoba-ku, Sendai 980-8579, Japan
| | - Keietsu Abe
- Laboratory of Applied Microbiology, Graduate School of Agricultural Science, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai 980-0845, Japan; New Industry Creation Hatchery Center (NICHe), Tohoku University, 6-6-10 Aoba, Aramaki, Aoba-ku, Sendai 980-8579, Japan
| | - Takahiro Shintani
- Laboratory of Bioindustrial Genomics, Graduate School of Agricultural Science, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai 980-0845, Japan
| | - Katsuya Gomi
- Laboratory of Bioindustrial Genomics, Graduate School of Agricultural Science, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai 980-0845, Japan.
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15
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Tanaka M, Yoshimura M, Ogawa M, Koyama Y, Shintani T, Gomi K. The C2H2-type transcription factor, FlbC, is involved in the transcriptional regulation of Aspergillus oryzae glucoamylase and protease genes specifically expressed in solid-state culture. Appl Microbiol Biotechnol 2016; 100:5859-68. [PMID: 26960315 DOI: 10.1007/s00253-016-7419-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 02/20/2016] [Accepted: 02/24/2016] [Indexed: 12/23/2022]
Abstract
Aspergillus oryzae produces a large amount of secreted proteins in solid-state culture, and some proteins such as glucoamylase (GlaB) and acid protease (PepA) are specifically produced in solid-state culture, but rarely in submerged culture. From the disruption mutant library of A. oryzae transcriptional regulators, we successfully identified a disruption mutant showing an extremely low production level of GlaB but a normal level of α-amylase production. This strain was a disruption mutant of the C2H2-type transcription factor, FlbC, which is reported to be involved in the regulation of conidiospore development. Disruption mutants of other upstream regulators comprising a conidiation regulatory network had no apparent effect on GlaB production in solid-state culture. In addition to GlaB, the production of acid protease in solid-state culture was also markedly decreased by flbC disruption. Northern blot analyses revealed that transcripts of glaB and pepA were significantly decreased in the flbC disruption strain. These results suggested that FlbC is involved in the transcriptional regulation of genes specifically expressed under solid-state cultivation conditions, possibly independent of the conidiation regulatory network.
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Affiliation(s)
- Mizuki Tanaka
- Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai, 981-8555, Japan
| | - Midori Yoshimura
- Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai, 981-8555, Japan
| | - Masahiro Ogawa
- Noda Institute for Scientific Research, 399 Noda, Noda, Chiba, 278-0037, Japan
| | - Yasuji Koyama
- Noda Institute for Scientific Research, 399 Noda, Noda, Chiba, 278-0037, Japan
| | - Takahiro Shintani
- Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai, 981-8555, Japan
| | - Katsuya Gomi
- Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai, 981-8555, Japan.
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16
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Purification and enzymatic characterization of secretory glycoside hydrolase family 3 (GH3) aryl β-glucosidases screened from Aspergillus oryzae genome. J Biosci Bioeng 2015; 120:614-23. [DOI: 10.1016/j.jbiosc.2015.03.019] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2015] [Revised: 03/19/2015] [Accepted: 03/28/2015] [Indexed: 01/28/2023]
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17
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Hiramoto T, Tanaka M, Ichikawa T, Matsuura Y, Hasegawa-Shiro S, Shintani T, Gomi K. Endocytosis of a maltose permease is induced when amylolytic enzyme production is repressed in Aspergillus oryzae. Fungal Genet Biol 2015; 82:136-44. [PMID: 26117687 DOI: 10.1016/j.fgb.2015.05.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2015] [Revised: 05/19/2015] [Accepted: 05/23/2015] [Indexed: 01/14/2023]
Abstract
In the filamentous fungus Aspergillus oryzae, amylolytic enzyme production is induced by the presence of maltose. Previously, we identified a putative maltose permease (MalP) gene in the maltose-utilizing cluster of A. oryzae. malP disruption causes a significant decrease in α-amylase activity and maltose consumption, indicating that MalP is a maltose transporter required for amylolytic enzyme production in A. oryzae. Although the expression of amylase genes and malP is repressed by the presence of glucose, the effect of glucose on the abundance of functional MalP is unknown. In this study, we examined the effect of glucose and other carbon sources on the subcellular localization of green fluorescence protein (GFP)-tagged MalP. After glucose addition, GFP-MalP at the plasma membrane was internalized and delivered to the vacuole. This glucose-induced internalization of GFP-MalP was inhibited by treatment with latrunculin B, an inhibitor of actin polymerization. Furthermore, GFP-MalP internalization was inhibited by repressing the HECT ubiquitin ligase HulA (ortholog of yeast Rsp5). These results suggest that MalP is transported to the vacuole by endocytosis in the presence of glucose. Besides glucose, mannose and 2-deoxyglucose also induced the endocytosis of GFP-MalP and amylolytic enzyme production was inhibited by the addition of these sugars. However, neither the subcellular localization of GFP-MalP nor amylolytic enzyme production was influenced by the addition of xylose or 3-O-methylglucose. These results imply that MalP endocytosis is induced when amylolytic enzyme production is repressed.
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Affiliation(s)
- Tetsuya Hiramoto
- Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan
| | - Mizuki Tanaka
- Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan
| | - Takanori Ichikawa
- Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan
| | - Yuka Matsuura
- Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan
| | - Sachiko Hasegawa-Shiro
- Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan
| | - Takahiro Shintani
- Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan
| | - Katsuya Gomi
- Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan.
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Hama S, Onodera K, Yoshida A, Noda H, Kondo A. Improved production of phospholipase A1 by recombinant Aspergillus oryzae through immobilization to control the fungal morphology under nutrient-limited conditions. Biochem Eng J 2015. [DOI: 10.1016/j.bej.2014.12.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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19
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Distinct mechanism of activation of two transcription factors, AmyR and MalR, involved in amylolytic enzyme production in Aspergillus oryzae. Appl Microbiol Biotechnol 2014; 99:1805-15. [PMID: 25487891 DOI: 10.1007/s00253-014-6264-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Revised: 11/16/2014] [Accepted: 11/18/2014] [Indexed: 12/21/2022]
Abstract
The production of amylolytic enzymes in Aspergillus oryzae is induced in the presence of starch or maltose, and two Zn2Cys6-type transcription factors, AmyR and MalR, are involved in this regulation. AmyR directly regulates the expression of amylase genes, and MalR controls the expression of maltose-utilizing (MAL) cluster genes. Deletion of malR gene resulted in poor growth on starch medium and reduction in α-amylase production level. To elucidate the activation mechanisms of these two transcription factors in amylase production, the expression profiles of amylases and MAL cluster genes under carbon catabolite derepression condition and subcellular localization of these transcription factors fused with a green fluorescent protein (GFP) were examined. Glucose, maltose, and isomaltose induced the expression of amylase genes, and GFP-AmyR was translocated from the cytoplasm to nucleus after the addition of these sugars. Rapid induction of amylase gene expression and nuclear localization of GFP-AmyR by isomaltose suggested that this sugar was the strongest inducer for AmyR activation. In contrast, GFP-MalR was constitutively localized in the nucleus and the expression of MAL cluster genes was induced by maltose, but not by glucose or isomaltose. In the presence of maltose, the expression of amylase genes was preceded by MAL cluster gene expression. Furthermore, deletion of the malR gene resulted in a significant decrease in the α-amylase activity induced by maltose, but had apparently no effect on the expression of α-amylase genes in the presence of isomaltose. These results suggested that activation of AmyR and MalR is regulated in a different manner, and the preceding activation of MalR is essential for the utilization of maltose as an inducer for AmyR activation.
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20
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Improved α-amylase production by Aspergillus oryzae after a double deletion of genes involved in carbon catabolite repression. Appl Microbiol Biotechnol 2013; 98:335-43. [DOI: 10.1007/s00253-013-5353-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2013] [Revised: 10/20/2013] [Accepted: 10/21/2013] [Indexed: 10/26/2022]
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21
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Hisada H, Tsutsumi H, Ishida H, Hata Y. High production of llama variable heavy-chain antibody fragment (VHH) fused to various reader proteins by Aspergillus oryzae. Appl Microbiol Biotechnol 2012; 97:761-6. [DOI: 10.1007/s00253-012-4211-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2012] [Revised: 05/21/2012] [Accepted: 06/03/2012] [Indexed: 10/28/2022]
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