WO2012063344A1 - 組換え酵母を用いたエタノールの製造方法 - Google Patents
組換え酵母を用いたエタノールの製造方法 Download PDFInfo
- Publication number
- WO2012063344A1 WO2012063344A1 PCT/JP2010/070076 JP2010070076W WO2012063344A1 WO 2012063344 A1 WO2012063344 A1 WO 2012063344A1 JP 2010070076 W JP2010070076 W JP 2010070076W WO 2012063344 A1 WO2012063344 A1 WO 2012063344A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- yeast
- xylose
- gene
- acetic acid
- ethanol
- Prior art date
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12P—FERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIRED CHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERS FROM A RACEMIC MIXTURE
- C12P7/00—Preparation of oxygen-containing organic compounds
- C12P7/02—Preparation of oxygen-containing organic compounds containing a hydroxy group
- C12P7/04—Preparation of oxygen-containing organic compounds containing a hydroxy group acyclic
- C12P7/06—Ethanol, i.e. non-beverage
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
- C12N15/00—Mutation or genetic engineering; DNA or RNA concerning genetic engineering, vectors, e.g. plasmids, or their isolation, preparation or purification; Use of hosts therefor
- C12N15/09—Recombinant DNA-technology
- C12N15/63—Introduction of foreign genetic material using vectors; Vectors; Use of hosts therefor; Regulation of expression
- C12N15/79—Vectors or expression systems specially adapted for eukaryotic hosts
- C12N15/80—Vectors or expression systems specially adapted for eukaryotic hosts for fungi
- C12N15/81—Vectors or expression systems specially adapted for eukaryotic hosts for fungi for yeasts
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
- C12N1/00—Microorganisms, e.g. protozoa; Compositions thereof; Processes of propagating, maintaining or preserving microorganisms or compositions thereof; Processes of preparing or isolating a composition containing a microorganism; Culture media therefor
- C12N1/38—Chemical stimulation of growth or activity by addition of chemical compounds which are not essential growth factors; Stimulation of growth by removal of a chemical compound
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12P—FERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIRED CHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERS FROM A RACEMIC MIXTURE
- C12P7/00—Preparation of oxygen-containing organic compounds
- C12P7/02—Preparation of oxygen-containing organic compounds containing a hydroxy group
- C12P7/04—Preparation of oxygen-containing organic compounds containing a hydroxy group acyclic
- C12P7/06—Ethanol, i.e. non-beverage
- C12P7/08—Ethanol, i.e. non-beverage produced as by-product or from waste or cellulosic material substrate
- C12P7/10—Ethanol, i.e. non-beverage produced as by-product or from waste or cellulosic material substrate substrate containing cellulosic material
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E50/00—Technologies for the production of fuel of non-fossil origin
- Y02E50/10—Biofuels, e.g. bio-diesel
Definitions
- the present invention relates to a method for producing ethanol using recombinant yeast having xylose metabolism ability.
- Patent Document 1 discloses a yeast in which a xylose reductase gene and a xylitol dehydrogenase gene derived from Pichia stipitis and a xylulokinase gene derived from S. cerevisiae are integrated into a chromosome.
- Non-Patent Documents 1 and 2 describe that xylose fermentation rate is reduced when yeast imparted with xylose metabolic ability is cultured in a fermentation medium containing acetic acid. Furthermore, Non-Patent Document 3 describes yeasts imparted with xylose fermentation ability and mutants with improved xylose fermentation rate.
- the present invention aims to provide a technique for improving ethanol productivity by improving xylose metabolism in yeast having xylose metabolism.
- the present invention includes the following.
- a method for producing ethanol comprising immersing a yeast having xylose-metabolizing ability in an acetic acid-containing solution, and then culturing the yeast in a xylose-containing medium and performing ethanol fermentation.
- xylose metabolism in yeast having xylose metabolism can be improved, and as a result, ethanol productivity is significantly improved.
- ethanol production method according to the present invention ethanol can be produced at low cost, for example, using woody biomass.
- the method for producing ethanol according to the present invention is a method of synthesizing ethanol from xylose contained in a medium by a recombinant yeast having xylose metabolizing ability, and includes a treatment step of bringing the recombinant yeast into contact with an acetic acid-containing solution. Through this step, the xylose metabolic capacity in the recombinant yeast is greatly improved, and the productivity of ethanol is greatly improved.
- ⁇ Recombinant yeast> In the recombinant yeast used in the method for producing ethanol according to the present invention, at least a xylose metabolism-related gene is introduced into the genome.
- This recombinant yeast can assimilate xylose contained in the medium to produce ethanol.
- the xylose contained in the medium may be obtained by a process of saccharifying xylan, hemicellulose or the like containing xylose as a constituent sugar, or xylan or hemicellulose or the like contained in the medium is saccharified by a saccharifying enzyme. May be supplied to the medium. In the latter case, it means a so-called simultaneous saccharification and fermentation system.
- Genes related to xylose metabolism are xylose reductase gene encoding xylose reductase that converts xylose to xylitol, xylitol dehydrogenase gene encoding xylitol dehydrogenase that converts xylitol to xylulose, and xylulose is phosphorylated to produce xylulose 5-phosphate It is meant to include a xylulokinase gene encoding xylulokinase. Xylulose 5-phosphate produced by xylulokinase enters the pentose phosphate pathway and is metabolized.
- the xylose metabolism-related gene introduced into the yeast genome is not particularly limited, and examples thereof include a xylose reductase gene and a xylitol dehydrogenase gene derived from Pichia stipitis, and a xylulokinase gene derived from Saccharomyces cerevisiae (Eliasson A. et al. Appl. Environ. Microbiol, 66: 3381-3386 and Toivari MN et al., Metab. Eng. 3: 236-249).
- a xylose reductase gene derived from Candida ⁇ ⁇ ⁇ tropicalis or Candida prapsilosis can be used as the xylose reductase gene.
- a xylitol dehydrogenase gene a xylitol dehydrogenase gene derived from Candida tropicalis or Candida prapsilosis can be used.
- a xylulokinase gene a xylulokinase gene derived from Pichia stipitis can also be used.
- a xylose isomerase gene derived from Streptomyces murinus cluster or the like can also be used.
- the recombinant yeast used in the method for producing ethanol according to the present invention may be a product into which a gene involved in sugar metabolism such as glucose is introduced in addition to the above-mentioned xylose metabolism-related gene.
- the recombinant yeast is preferably a yeast having ⁇ -glucosidase activity by introducing a ⁇ -glucosidase gene.
- ⁇ -glucosidase activity means an activity catalyzing a reaction of hydrolyzing a ⁇ -glycoside bond of a sugar. That is, ⁇ -glucosidase can decompose cellooligosaccharides such as cellobiose into glucose.
- the ⁇ -glucosidase gene is preferably introduced as a cell surface display type gene.
- the cell surface display type gene is a gene modified so that a protein encoded by the gene is expressed so as to be displayed on the surface layer of the cell.
- the cell surface-presenting ⁇ -glucosidase gene is a gene obtained by fusing a ⁇ -glucosidase gene and a cell surface localized protein gene.
- the cell surface localized protein refers to a protein that is fixed on the cell surface of yeast and is present on the cell surface.
- ⁇ - or a-agglutinin which is an aggregating protein, FLO protein and the like can be mentioned.
- a cell surface localized protein has a secretory signal sequence on the N-terminal side and a GPI anchor attachment recognition signal on the C-terminal side. Although it has the same secretory protein in that it has a secretion signal, the cell surface localized protein is different from the secreted protein in that it is transported by being fixed to the cell membrane via the GPI anchor.
- the GPI anchor attachment recognition signal sequence is selectively cleaved, and is bound to the GPI anchor at the newly protruding C-terminal portion and fixed to the cell membrane. Thereafter, the base of the GPI anchor is cleaved by phosphatidylinositol-dependent phospholipase C (PI-PLC).
- PI-PLC phosphatidylinositol-dependent phospholipase C
- the ⁇ -glucosidase gene is not particularly limited, and examples thereof include ⁇ -glucosidase genes derived from Aspergillus aculeatus (Murai et al., Appl. Environ. Microbiol. 64: 4857-4861).
- a ⁇ -glucosidase gene a ⁇ -glucosidase gene derived from Aspergillus oryzae, a ⁇ -glucosidase gene derived from Clostridium cellulovorans, a ⁇ -glucosidase gene derived from Saccharomycopsis fibligera, and the like can be used.
- yeasts such as Candida Shehatae, Pichia stipitis, Pachysolen tannophilus, Saccharomyces cerevisiae and Schizosaccaromyces pombe, and Saccharomyces cerevisiae is particularly preferable.
- the yeast may be an experimental strain used for experimental convenience, or an industrial strain (practical strain) used for practical utility. Examples of industrial strains include yeast strains used for wine, sake and shochu making.
- yeast having homothallic properties it is preferable to use as the host yeast. According to the technique disclosed in Japanese Patent Application Laid-Open No. 2009-34036, it is possible to easily introduce a multicopy gene into a genome by using a yeast having homothallic properties.
- Yeast having homothallic properties is synonymous with homothallic yeast.
- the yeast having homothallic properties is not particularly limited, and any yeast can be used. Examples of yeast having homothallic properties include, but are not limited to, Saccharomyces cerevisiae OC-2 strain (NBRC2260).
- yeasts with homothallic properties include alcoholic yeasts (Taken 396, NBRC0216) (Source: “Characteristics of alcoholic yeasts”, Sakekenkaiho, No37, p18-22 (1998.8)), isolated in Brazil and Okinawa Ethanol producing yeast (Source: “Genetic properties of wild strains of Saccharomyces cerevisiae isolated in Brazil and Okinawa” Journal of Japanese Agricultural Chemistry, Vol. 65, No. 4, p759-762 (1991.4)) and 180 (Source: Alcohol The screening of yeast with strong fermenting ability ”, Journal of Japan Brewing Association, Vol.82, No.6, p439-443 (1987.6)).
- yeast having homothallic properties can be used as a yeast having homothallic properties by introducing the HO gene so that it can be expressed. That is, in the present invention, the yeast having homothallic properties is meant to include yeast into which the HO gene has been introduced so as to be expressed.
- the Saccharomyces cerevisiae OC-2 strain is preferable because it is a strain that has been confirmed to be safe and has been used in the winemaking scene. Further, the Saccharomyces cerevisiae OC-2 strain is preferable because it has excellent promoter activity under high sugar concentration conditions, as shown in the Examples described later. In particular, the Saccharomyces cerevisiae OC-2 strain is preferable because of its excellent promoter activity of the pyruvate decarboxylase gene (PDC1) under high sugar concentration conditions.
- PDC1 pyruvate decarboxylase gene
- the promoter of the gene to be introduced is not particularly limited.
- the promoter of glyceraldehyde 3-phosphate dehydrogenase gene (TDH3), the promoter of 3-phosphoglycerate kinase gene (PGK1), the hyperosmotic response 7 gene ( HOR7) promoters can be used.
- the pyruvate decarboxylase gene (PDC1) promoter is preferred because of its high ability to highly express a downstream target gene.
- the above-described gene may be introduced into the yeast genome together with a promoter controlling expression and other expression control regions.
- the above-described gene may be introduced so that the expression is controlled by a promoter of a gene originally present in the genome of yeast as a host or other expression control regions.
- any conventionally known method known as a yeast transformation method can be applied. Specifically, for example, electroporation method “Meth. Enzym., 194, p182 (1990)”, spheroplast method “Proc. Natl. Acad. Sci. USA, 75 p1929 (1978)”, acetic acid Lithium Method “J. Bacteriology, 153, p163 (1983)”, Proc. Natl. Acad. Sci. USA, 75 p1929 (1978), Methods in yeast genetics, 2000 Edition: A Cold Spring Harbor Laboratory Course Manual The method can be implemented, but is not limited thereto.
- acetic acid-containing solution may be either an acetic acid aqueous solution or a liquid medium containing acetic acid.
- the aqueous acetic acid solution can be obtained by dissolving acetic acid in water.
- the liquid medium containing acetic acid can be prepared by adding acetic acid to a medium for yeast such as SD medium, YPD medium, YPAD medium, and YM medium.
- the concentration of acetic acid contained in the acetic acid-containing solution is not particularly limited, but is, for example, 1 to 20 g / l, preferably 2 to 10 g / l, more preferably 3 to 5 g / l. If the concentration of acetic acid contained in the acetic acid-containing solution is below the above range, the xylose metabolic capacity in the recombinant yeast may not be significantly improved. Moreover, when the acetic acid concentration contained in an acetic acid containing solution exceeds the said range, there exists a possibility of inhibiting the growth of the said recombinant yeast.
- the treatment for bringing the recombinant yeast into contact with the acetic acid-containing solution is not particularly limited, but for example, 1 hour or longer, preferably 3 hours or longer, more preferably 10 hours or longer.
- the contact time between the recombinant yeast and the acetic acid-containing solution is less than the above range, the xylose metabolic capacity in the recombinant yeast may not be significantly improved.
- the treatment for bringing the recombinant yeast into contact with the acetic acid-containing solution may be stirred or shaken in a state where the recombinant yeast is added to the acetic acid-containing solution.
- the solution temperature is, for example, 20 to 40 ° C., preferably 25 to 37 ° C., more preferably 28 to 35 ° C.
- the treatment of bringing the recombinant yeast into contact with the acetic acid-containing solution is preferably performed under aerobic conditions using a liquid medium containing acetic acid as the acetic acid-containing solution.
- a liquid medium containing acetic acid as the acetic acid-containing solution.
- the recombinant yeast After bringing the recombinant yeast into contact with the acetic acid-containing solution, the recombinant yeast is recovered from the acetic acid-containing solution and subjected to ethanol fermentation in a xylose-containing medium.
- a technique such as centrifugation or filtration can be applied.
- it is desirable to remove the acetic acid-containing solution as much as possible.
- a predetermined amount of acetic acid-containing solution may be brought into the xylose-containing medium.
- the xylose-containing medium for ethanol fermentation may be a medium containing at least xylose as a carbon source, and may be a medium containing other carbon sources such as glucose.
- the saccharified liquid after saccharifying-processing cellulose-type biomass can be used for the culture medium utilized for ethanol fermentation.
- the saccharified solution contains xylose derived from hemicellulose contained in the cellulosic biomass.
- the medium used for ethanol fermentation may be a medium containing cellulosic biomass.
- ethanol fermentation by the recombinant yeast is a so-called simultaneous saccharification and fermentation process.
- the simultaneous saccharification and fermentation treatment means a treatment that is carried out simultaneously without distinguishing between the step of saccharifying cellulosic biomass and the ethanol fermentation step.
- a conventionally known pretreatment may be applied to the cellulosic biomass.
- pre-processing For example, the process which decomposes
- the recombinant yeast can assimilate xylose contained in the medium to produce ethanol.
- the saccharification method is not particularly limited, and examples thereof include an enzyme method using a cellulase preparation such as cellulase or hemicellulase.
- the cellulase preparation contains a plurality of enzymes involved in the degradation of cellulose chains and hemicellulose chains, and exhibits a plurality of activities such as endoglucanase activity, endoxylanase activity, cellobiohydrolase activity, glucosidase activity, and xylosidase activity.
- the cellulase preparation is not particularly limited, and examples thereof include cellulase produced by Trichoderma reesei, Acremonium cerulolyticus, and the like.
- As the cellulase preparation a commercially available product may be used.
- a cellulase preparation and the above-described recombinant microorganism are added to a medium containing cellulosic biomass (which may be after pretreatment), and the recombinant yeast is cultured in a predetermined temperature range.
- the culture temperature is not particularly limited, but can be 25 to 45 ° C., preferably 30 to 40 ° C. in consideration of the efficiency of ethanol fermentation.
- the pH of the culture solution is preferably 4-6. Moreover, you may stir and shake in the case of culture
- ethanol is recovered from the medium after ethanol fermentation.
- the method for recovering ethanol is not particularly limited, and any conventionally known method can be applied.
- a liquid layer containing ethanol and a solid layer containing recombinant yeast and solid components are separated by solid-liquid separation operation.
- ethanol contained in the liquid layer is separated and purified by a distillation method, whereby high purity ethanol can be recovered.
- the purity of ethanol can be adjusted as appropriate according to the intended use of ethanol.
- Example 1 GRE3 of the diploid yeast OC2-T strain (Saitoh, S. et al., J. Ferment. Bioeng. 1996, 81, 98-103) was used for the production of xylose-utilizing yeast. One copy was disrupted and XYL1, XYL2 and XKS1 genes were introduced.
- XYL1, XYL2, XKS1 gene overexpression / GRE3 gene disruption DNA fragment preparation DNA fragment containing the GRE3 gene and its 5 'upstream and 3' downstream untranslated region using genomic DNA of yeast BY4742 (Open Biosystems) as a template was amplified by PCR.
- TB2358 (5′-TGGGAATATTACCGCTCGAAG-3 ′: SEQ ID NO: 1) and TB2359 (5′-AAGGGGGAAGGTGTGGAATC-3 ′: SEQ ID NO: 2) were used as PCR primers, respectively.
- the PCR primer design for the DNA sequence amplification of yeast BY4742 strain was referred to the DNA sequence data of Saccharomyces Genome Database.
- a linear DNA fragment containing the full length of pUC19 that was cleaved at the multicloning site of pUC19 was amplified by PCR.
- TB2373 (5′-CACACCTTCCCCCTTGATCCTCTAGAGTCGACC-3 ′: SEQ ID NO: 3) and TB2374 (5′-GCGGTAATATTCCCAGATCCCCGGGTACCGAGCTC-3 ′: SEQ ID NO: 4) were used as PCR primers, respectively.
- the above two DNA fragments were cloned using In-Fusion TM Advantage PCR Cloning Kit (Takara Bio) and named pUC19-5U_GRE3-GRE3-3U_GRE3.
- the primers for PCR are TB3018 (5'-AACGAGGCGCGCTCTTCCAGCCAGTAAAATCCA-3 ': SEQ ID NO: 5) and TB3017 (5'-GCTATGGTGTGTGGGCTTTAAAAAATTTCCAATTTTCCTTTACG-3': SEQ ID NO: 6), TB2210 (5'-CCCACACACCATAGCTTCAAAATG-3 ': SEQ ID NO: 7) TB2269 (5'-TCTTTAGATTAGATTGCTATGCTTTCTTTCTAATGAGCAAG-3 ': SEQ ID NO: 8), TB2345 (5'-AATCTAATCTAAAGAATGTTGTGTTCAGTAATTCAGAGAC-3': SEQ ID NO: 9) and TB2346 (5'-CTGCGGCCGGCCGCATTAGATGAGAGTCT1TCCAGTTC-3 ': 1 TGCGGCCGGCCGCAGC-3 ′: SEQ ID NO: 11) and TB2683 (5′-GCGCCTCGTTCAGAAT
- a linear DNA fragment containing the entire length of the plasmid as cleaved between the HIS3 terminator region and the 3 ′ downstream untranslated region of the GRE3 gene, and the yeast BY4742 strain was amplified by PCR using a DNA fragment containing the TDH2 promoter region, a DNA fragment containing the ILV3 terminator region, and a genomic DNA of Pichia stipitis as a template.
- the primers for PCR are TB9020 (5'-TCCAGCCAGTAAAATCCATAC-3 ': SEQ ID NO: 13), TB2457 (5'-CCGTCAAGAGAGCGCGCCTCGTTCAG-3': SEQ ID NO: 14), TB2844 (5'-GCGCTCTCTTGACGGGTATTCTGAGCATCTTAC-3 ': SEQ ID NO: 15).
- TB2595 (5'-TTTGTTTTGTTTGTTTGTGTGATGAATTTAATTTG-3 ': SEQ ID NO: 16), TB2314 (5'-AACAAACAAAACAAAATGCCTTCTATTAAGTTGAAC-3': SEQ ID NO: 17) and TB2455 (5'-GGGGCCTATAATGCATTAGACGAAGATAGGAATCTTG-3 ': SEQ ID NO: 18, TB4 AACAAACAAAACAAAATGCCTTCTATTAAGTTGAAC-3 ′: SEQ ID NO: 19) and TB3019 (5′-ATTTTACTGGCTGGAATTTCGTAGATTATAATTAAGGCGAC-3 ′: SEQ ID NO: 20) were used.
- PCR primer design for XYL1 gene sequence amplification referred to the Pichia stipitis XYL1 gene (registration number XM_001385144) registered in GeneBank.
- the above four DNA fragments were cloned using In-Fusion TM Advantage PCR Cloning Kit and named pUC19-5U_GRE3-P_TEF1-XKS1-T_HIS3-P_TDH2-XYL1-T_ILV3-3U_GRE3.
- pUC19-5U_GRE3-P_TEF1-XKS1-T_HIS3-P_TDH2-XYL1-T_ILV3-3U_GRE3 as a template, linear DNA containing the entire length of the plasmid as cleaved between the ILV3 terminator region and the 3 'downstream untranslated region of the GRE3 gene
- the XYL2 gene was amplified by PCR using the fragment, genomic DNA of yeast BY4742 strain as a template, DNA fragment containing PDC1 promoter region and DNA fragment containing ILV6 terminator region, and genomic DNA of Pichia stipitis.
- the primers for PCR were TB2375 (5'-AGTTGCTTGACACGGTGGAAGAAGGTCCAGCCAGTAAAATCCATA-3 ': SEQ ID NO: 21) and TB3021 (5'-ATTTCGTAGATTATAATTAAGGCGAC-3': SEQ ID NO: 22), TB2010 (5'-TTTGATTGATTTGACTGTGTTATTTTGC-3 ': SEQ ID NO: 23), respectively.
- TB2261 (5'-CCGTGTCAAGCAACTATGGG-3 ': SEQ ID NO: 24), TB3022 (5'-TATAATCTACGAAATTAATAAGAAAGGTGACCGTG-3': SEQ ID NO: 25) and TB2347 (5'-GTTAGTCTCTCGGCCTTGCG-3 ': SEQ ID NO: 26), TB2351 (5'- GGCCGAGAGACTAACTTACTCAGGGCCGTCAAT-3 ′: SEQ ID NO: 27) and TB2352 (5′-GTCAAATCAATCAAAATGACTGCTAACCCTTCC-3 ′: SEQ ID NO: 28) were used.
- the PCR primer design for XYL2 gene sequence amplification was based on the Pichia stipitis XYL2 gene (registration number AF127801 or X55392) registered in GeneBank.
- the above four DNA fragments were cloned using In-Fusion TM Advantage PCR Cloning Kit and named pUC19-5U_GRE3-P_TEF1-XKS1-T_HIS3-P_TDH2-XYL1-T_ILV3-ILV6_T-XYL2-PDC1_P-3U_GRE3.
- XYL1, XYL2, XKS1 gene overexpression / GRE3 gene hetero- disruption strain preparation Using XYL1, XYL2, XKS1 gene over-expression / GRE3 gene disruption DNA fragment, the OC2-T strain was frozen using the Frozen-EZ Yeast Transformation II kit (ZYMO RESEARCH ) Was used and transformed according to the protocol attached to the kit. After transformation, it was spread on a plate using xylose as a sole carbon source and cultured at 30 ° C. for 7 days to obtain a transformant.
- ZYMO RESEARCH Frozen-EZ Yeast Transformation II kit
- Genomic DNA was prepared from the transformant, and TB2356 (5'-TGGGGCTAAACGAGATTTGG-3 ': SEQ ID NO: 29) and TB592 (5'-GAAATTTAGTATGCTGTGCTTGGG-3': primers outside the inserted DNA fragment and inside the vector were prepared by PCR. Using SEQ ID NO: 30), it was confirmed that one copy was normally integrated into the chromosome.
- YPD medium yeast extract 10 g / L, peptone 20 g / L glucose 20 g / L
- YPD acetate medium yeast extract 10 g / L, peptone 20 g / L glucose 20 g / L, Acetic acid 1-5 g / L; adjusted to pH 5 with ammonia
- the cells were collected by centrifugation (2000 g, 3 minutes).
- Xylose medium (xylose 60 g / L, yeast extract 10 g / L), glucose / xylose medium (glucose 90 g / L, xylose 60 g / L, yeast extract 10 g / L) or glucose medium (glucose 90 g / L, yeast extract 10 g / L) L)
- glucose medium (glucose 90 g / L, yeast extract 10 g / L) L)
- concentrations of ethanol and xylose were measured with (LC-10A; Shimadzu Corporation).
- the column uses AminexHPX-87H (Bio-Rad), the detector uses a differential refractive index detector RID-10A (Shimadzu Corporation), mobile phase 0.01N H 2 SO 4 , flow rate 0.6 ml / min, temperature Analyzed at 30 ° C.
- the analysis result of ethanol concentration is shown in FIG. As shown in FIG. 2, as a result of the fermentation test, it is clear that in the xylose medium, the ethanol production rate is improved in the treated group added with 3 g / L or more of acetic acid to the culture solution compared to the non-acetic acid-treated group. became. On the other hand, in the glucose medium, there was no difference in the ethanol production rate.
- the analysis result of the xylose concentration is shown in FIG. As shown in FIG. 3, when the glucose / xylose medium was used, the consumption rate of xylose was improved in the treatment group added with 3 g / L or more of acetic acid, but the glucose consumption was not different from the control.
- the recombinant yeast having the ability to metabolize xylose is brought into contact with an acetic acid-containing solution (in this example, a liquid medium containing acetic acid), so that the xylose-metabolizing ability in the recombinant yeast can be obtained. It became clear that improved significantly. In addition, even when a recombinant yeast having xylose metabolic ability was brought into contact with an acetic acid-containing solution, the glucose metabolic ability of the recombinant yeast was not greatly improved.
- an acetic acid-containing solution in this example, a liquid medium containing acetic acid
Abstract
Description
本発明に係るエタノールの製造方法に使用される組換え酵母は、少なくともキシロース代謝関連遺伝子がゲノムに導入されている。この組換え酵母は、培地中に含まれるキシロースを資化してエタノールを生産することができる。なお、培地中に含まれるキシロースとは、キシロースを構成糖とするキシランやヘミセルロース等を糖化するプロセスによって得られたものでも良いし、培地に含まれるキシランやヘミセルロース等が糖化酵素により糖化されることで培地に供給されるものであってもよい。後者の場合は、所謂、同時糖化発酵の系を意味する。
上述したキシロース代謝関連遺伝子を宿主となる酵母ゲノムに導入することにより、本発明に使用できる組換え酵母を作製することができる。宿主として用いることができる酵母としては、特に限定するものではないがCandida Shehatae、Pichia stipitis、Pachysolen tannophilus、Saccharomyces cerevisiae及びSchizosaccaromyces pombeなどの酵母が挙げられ、特にSaccharomyces cerevisiaeが好ましい。また、酵母としては、実験面での利便性のために使われる実験株でも良いし、実用面での有用性のために使われている工業株(実用株)でも良い。工業株としては、例えば、ワイン、清酒や焼酎作りに用いられる酵母株を挙げることができる。
以上で説明した組換え酵母を使用してエタノールを製造する際には、キシロース含有培地にてエタノール発酵培養を行う前に、当該組換え酵母を酢酸含有溶液に接触させる処理を行う。ここで、酢酸含有溶液は、酢酸水溶液、酢酸を含有する液体培地のいずれでも良い。酢酸水溶液は、酢酸を水に溶解することでして得られる。また、酢酸を含有する液体培地は、SD培地、YPD培地、YPAD培地、YM培地といった酵母用の培地に酢酸を添加することで調整できる。ここで、酢酸含有溶液に含まれる酢酸濃度は、特に限定されないが、例えば1~20g/l、好ましくは2~10g/l、より好ましくは3~5g/lである。酢酸含有溶液に含まれる酢酸濃度が上記範囲を下回る場合、上記組換え酵母におけるキシロース代謝能を顕著に向上できない虞がある。また、酢酸含有溶液に含まれる酢酸濃度が上記範囲を上回る場合、上記組換え酵母の生育を阻害する虞がある。
本実施例では、キシロース資化酵母の作製のため、2倍体酵母のOC2-T株(Saitoh, S.ら、J. Ferment. Bioeng. 1996年、81巻、98-103頁)のGRE3を1コピー破壊して、XYL1、XYL2及びXKS1遺伝子を導入した。
酵母BY4742株(Open Biosystems)のゲノムDNAを鋳型として、GRE3遺伝子とその5’上流・3’下流非翻訳領域とを含むDNA断片をPCRで増幅した。PCR用プライマーはそれぞれTB2358(5'-TGGGAATATTACCGCTCGAAG-3':配列番号1)とTB2359(5'-AAGGGGGAAGGTGTGGAATC-3':配列番号2)を使用した。なお、酵母BY4742株のDNA配列増幅ためのPCRプライマー設計は、Saccharomyces Genome DatabaseのDNA配列データを参考にした。プラスミドpUC19を鋳型として、pUC19のマルチクローニングサイトで切断されるようなpUC19全長を含む直鎖状DNA断片をPCRで増幅した。PCR用プライマーはそれぞれTB2373(5'-CACACCTTCCCCCTTGATCCTCTAGAGTCGACC-3':配列番号3)とTB2374(5'-GCGGTAATATTCCCAGATCCCCGGGTACCGAGCTC-3':配列番号4)を使用した。上記二つのDNA断片をIn-FusionTM Advantage PCR Cloning Kit(タカラバイオ)を用いてクローニングし、pUC19-5U_GRE3-GRE3-3U_GRE3と命名した。
XYL1、XYL2、XKS1遺伝子過剰発現・GRE3遺伝子破壊用DNA断片を用いて、OC2-T株をFrozen-EZ Yeast Transformation IIキット(ZYMO RESEARCH)を用いて、キット添付のプロトコールに従い、形質転換した。形質転換後、キシロースを単独炭素源としたプレートにまいて、30℃で7日間培養し、形質転換体を得た。形質転換体よりゲノムDNAを調製し、PCR法により挿入DNA断片の外側とベクター内側のプライマーであるTB2356(5'-TGGGGCTAAACGAGATTTGG-3':配列番号29)とTB592(5'-GAAATTTAGTATGCTGTGCTTGGG-3':配列番号30)を用いて、染色体に正常に1コピー組込まれていることを確認した。
得られた形質転換体についてYPD培地(イーストエキストラクト 10g/L、ペプトン 20g/Lグルコース20g/L)もしくは、YPD酢酸培地(イーストエキストラクト 10g/L、ペプトン 20g/Lグルコース20g/L、酢酸1~5g/L; アンモニアでpH5に調整)に植菌し、30℃で24時間震盪培養を行った。培養終了後、遠心分離(2000g、3分)により菌体を回収した。
Claims (5)
- キシロース代謝能を有する酵母を酢酸含有溶液に接触させる工程と、その後、キシロース含有培地にて当該酵母を培養してエタノール発酵を行う工程とを有するエタノールの製造方法。
- 上記酵母は、キシロース代謝関連遺伝子が導入された組換え酵母であることを特徴とする請求項1記載のエタノールの製造方法。
- 上記キシロース代謝関連遺伝子は、キシロースリダクターゼ遺伝子、キシリトールデヒドロゲナーゼ遺伝子及びキシルロキナーゼ遺伝子であることを特徴とする請求項2記載のエタノールの製造方法。
- 上記酵母を酢酸含有溶液に接触させる際、好気条件とすることを特徴とする請求項1記載のエタノールの製造方法。
- 上記酢酸含有溶液は、酵母用培地に酢酸を添加した組成であることを特徴とする請求項1記載のエタノールの製造方法。
Priority Applications (6)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CA2819315A CA2819315C (en) | 2010-11-11 | 2010-11-11 | Method for producing ethanol using recombinant yeast strain |
JP2012542764A JP5590140B2 (ja) | 2010-11-11 | 2010-11-11 | 組換え酵母を用いたエタノールの製造方法 |
US13/883,670 US8859248B2 (en) | 2010-11-11 | 2010-11-11 | Method for producing ethanol using recombinant yeast strain |
CN201080069741.5A CN103180451B (zh) | 2010-11-11 | 2010-11-11 | 使用重组酵母的乙醇的制造方法 |
BR112013011473-8A BR112013011473B1 (pt) | 2010-11-11 | 2010-11-11 | Processo para produção de etanol usando linhagem de levedura recombinante |
PCT/JP2010/070076 WO2012063344A1 (ja) | 2010-11-11 | 2010-11-11 | 組換え酵母を用いたエタノールの製造方法 |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/JP2010/070076 WO2012063344A1 (ja) | 2010-11-11 | 2010-11-11 | 組換え酵母を用いたエタノールの製造方法 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2012063344A1 true WO2012063344A1 (ja) | 2012-05-18 |
Family
ID=46050525
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2010/070076 WO2012063344A1 (ja) | 2010-11-11 | 2010-11-11 | 組換え酵母を用いたエタノールの製造方法 |
Country Status (6)
Country | Link |
---|---|
US (1) | US8859248B2 (ja) |
JP (1) | JP5590140B2 (ja) |
CN (1) | CN103180451B (ja) |
BR (1) | BR112013011473B1 (ja) |
CA (1) | CA2819315C (ja) |
WO (1) | WO2012063344A1 (ja) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2015042145A (ja) * | 2013-08-26 | 2015-03-05 | 王子ホールディングス株式会社 | エタノールの製造方法 |
JP2015521043A (ja) * | 2012-06-01 | 2015-07-27 | ルサッフル・エ・コンパニーLesaffre Et Compagnie | キシロースを代謝でき、阻害因子に耐性がある酵母菌株、その酵母菌株を得るための方法およびその使用 |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP6879111B2 (ja) * | 2017-08-02 | 2021-06-02 | トヨタ自動車株式会社 | 組換え酵母及びこれを用いたエタノールの製造方法 |
CN108823112B (zh) * | 2018-06-15 | 2023-11-17 | 首都师范大学 | 定向优化木糖代谢途径提高乙醇产量的方法及工程酿酒酵母 |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2009195220A (ja) * | 2008-01-24 | 2009-09-03 | National Institute Of Advanced Industrial & Technology | キシロース発酵能が優れた六炭糖・五炭糖同時発酵酵母およびそれを用いたエタノールの高効率生産方法 |
JP2010239925A (ja) * | 2009-04-08 | 2010-10-28 | Toyota Central R&D Labs Inc | キシロースを利用して有用物質を生産する方法 |
Family Cites Families (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5866382A (en) * | 1990-04-06 | 1999-02-02 | Xyrofin Oy | Xylose utilization by recombinant yeasts |
DE60325457D1 (de) * | 2002-01-23 | 2009-02-05 | Royal Nedalco B V | Fermentation von pentosezuckern |
US7253001B2 (en) * | 2002-03-19 | 2007-08-07 | Forskarpatent I Syd Ab | Metabolic engineering for improved xylose utilisation of Saccharomyces cerevisiae |
WO2004085627A1 (en) * | 2003-03-26 | 2004-10-07 | Forskarpatent I Syd Ab | New saccharomyces cerevisiae strains utilizing xylose |
PL1626979T3 (pl) * | 2003-05-02 | 2012-09-28 | Cargill Inc | Genetycznie modyfikowane gatunki drożdży i sposoby fermentacji z użyciem genetycznie modyfikowanych drożdży |
DE102007030689C5 (de) * | 2007-06-30 | 2015-03-19 | Porextherm-Dämmstoffe Gmbh | Vakuum-Isolations-Paneel und Verfahren zu dessen Herstellung |
WO2009109630A1 (en) * | 2008-03-07 | 2009-09-11 | Dsm Ip Assets B.V. | A pentose sugar fermenting cell |
US8440449B2 (en) * | 2008-09-30 | 2013-05-14 | The United States Of America, As Represented By The Secretary Of Agriculture | Transformed Saccharomyces cerevisiae engineered for xylose utilization |
US8728781B2 (en) * | 2009-03-13 | 2014-05-20 | University Of Washington Through Its Center Of Commercialization | Endophytic yeast strains, methods for ethanol and xylitol production, methods for biological nitrogen fixation, and a genetic source for improvement of industrial strains |
JP5804327B2 (ja) * | 2009-11-30 | 2015-11-04 | 国立大学法人神戸大学 | バイオマスからのエタノールの生産方法 |
WO2011071204A2 (ko) * | 2009-12-12 | 2011-06-16 | 서울대학교 산학협력단 | Nadh 및 nad+의 사용이 커플링된 재조합 사카로마이세스 세레비지애를 이용하여 자일로오스로부터 에탄올을 생산하는 방법 |
US20110262983A1 (en) * | 2010-03-31 | 2011-10-27 | The United States Of America As Represented By The Secretary Of Agriculture | Metabolically engineered yeasts for the production of ethanol and other products from xylose and cellobiose |
CA2798937A1 (en) * | 2010-05-28 | 2011-12-01 | Codexis, Inc. | Pentose fermentation by a recombinant microorganism |
-
2010
- 2010-11-11 US US13/883,670 patent/US8859248B2/en active Active
- 2010-11-11 CA CA2819315A patent/CA2819315C/en active Active
- 2010-11-11 BR BR112013011473-8A patent/BR112013011473B1/pt active IP Right Grant
- 2010-11-11 JP JP2012542764A patent/JP5590140B2/ja active Active
- 2010-11-11 CN CN201080069741.5A patent/CN103180451B/zh active Active
- 2010-11-11 WO PCT/JP2010/070076 patent/WO2012063344A1/ja active Application Filing
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2009195220A (ja) * | 2008-01-24 | 2009-09-03 | National Institute Of Advanced Industrial & Technology | キシロース発酵能が優れた六炭糖・五炭糖同時発酵酵母およびそれを用いたエタノールの高効率生産方法 |
JP2010239925A (ja) * | 2009-04-08 | 2010-10-28 | Toyota Central R&D Labs Inc | キシロースを利用して有用物質を生産する方法 |
Non-Patent Citations (5)
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2015521043A (ja) * | 2012-06-01 | 2015-07-27 | ルサッフル・エ・コンパニーLesaffre Et Compagnie | キシロースを代謝でき、阻害因子に耐性がある酵母菌株、その酵母菌株を得るための方法およびその使用 |
JP2015042145A (ja) * | 2013-08-26 | 2015-03-05 | 王子ホールディングス株式会社 | エタノールの製造方法 |
Also Published As
Publication number | Publication date |
---|---|
BR112013011473B1 (pt) | 2022-08-09 |
BR112013011473A2 (pt) | 2021-08-24 |
JPWO2012063344A1 (ja) | 2014-05-12 |
CN103180451B (zh) | 2014-12-31 |
CN103180451A (zh) | 2013-06-26 |
CA2819315A1 (en) | 2012-05-18 |
CA2819315C (en) | 2015-11-03 |
US20130224815A1 (en) | 2013-08-29 |
US8859248B2 (en) | 2014-10-14 |
JP5590140B2 (ja) | 2014-09-17 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP6087854B2 (ja) | 組換え酵母を用いたエタノールの製造方法 | |
JP5817836B2 (ja) | 組換え酵母を用いたエタノールの製造方法 | |
JP5590140B2 (ja) | 組換え酵母を用いたエタノールの製造方法 | |
US10745684B2 (en) | Recombinant yeast and a method for producing ethanol using the same | |
US10017788B2 (en) | Recombinant yeast and method for producing ethanol using the same | |
JP6447583B2 (ja) | 組換え酵母、及びそれを用いたエタノールの製造方法 | |
WO2014021163A1 (ja) | 組換え酵母を用いたエタノールの製造方法 | |
WO2020032233A1 (ja) | 組換え酵母、及びそれを用いたエタノールの製造方法 | |
CA3020447A1 (en) | Recombinant yeast and method for producing ethanol using the same | |
US11193113B2 (en) | Transgenic yeast and method for producing ethanol using the same | |
US20220073896A1 (en) | Recombinant yeast and method for producing ethanol using same |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 10859554 Country of ref document: EP Kind code of ref document: A1 |
|
DPE1 | Request for preliminary examination filed after expiration of 19th month from priority date (pct application filed from 20040101) | ||
WWE | Wipo information: entry into national phase |
Ref document number: 2012542764 Country of ref document: JP |
|
ENP | Entry into the national phase |
Ref document number: 2819315 Country of ref document: CA |
|
WWE | Wipo information: entry into national phase |
Ref document number: 13883670 Country of ref document: US |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 10859554 Country of ref document: EP Kind code of ref document: A1 |
|
REG | Reference to national code |
Ref country code: BR Ref legal event code: B01A Ref document number: 112013011473 Country of ref document: BR |
|
ENP | Entry into the national phase |
Ref document number: 112013011473 Country of ref document: BR Kind code of ref document: A2 Effective date: 20130509 |