164 results about "Carboxysome" patented technology

The invention discloses construction and application of an L-malic acid producing issatchenkia orientalis strain, and belongs to the technical field of microorganisms and the technical field of microbial fermentation and metabolic engineering. Through a metabolic engineering means, a cytoplasm metabolic pathway of an issatchenkia orientalis strain is transformed, and a pyruvate decarboxylase coding gene, glycerol dehydrogenase and lactic dehydrogenase are knocked out; a pyruvate carboxylase gene derived from aspergillus flavus, a malate dehydrogenase gene derived from corynebacterium glutamicum and phosphoenolpyruvate carboxylase derived from escherichia coli are screened and integrated, so that a cytoplasm rTCA cycle synthesis pathway is enhanced; inserting a dicarboxylic acid external transporter gene from schizosaccharomyces cerevisiae at a neutral site GD21, and knocking out endogenous dicarboxylic acid internal transporter; the L-malic acid yield of the modified yeast strain in the fermentation process is remarkably increased and reaches 140.16 g / L. The engineering strain provided by the invention has good industrial application potential in efficient L-malic acid production.

The invention discloses bacillus subtilis with high yield of surfactin, a related enzyme mutant and a preparation method of the bacillus subtilis, the bacillus subtilis is obtained by a gene modification method and can produce the surfactin with high yield, and the highest yield can reach 9.4 g / L; the invention also provides key enzyme mutants participating in surfactin synthesis in the bacillus subtilis, and the key enzyme mutants comprise a biotin carboxylase IdeHA mutant, a biotin carboxylase accBC mutant, an enoyl reductase FabI mutant, a malonyl transferase FabD mutant and a dihydrolipoyl dehydrogenase IPdU mutant. The key enzyme mutants comprise a biotin carboxylase IdeHA mutant, a biotin carboxylase accBC mutant, an enoyl reductase FabI mutant, a malonyl transferase FabD mutant and a dihydrolipoyl dehydrogenase IPdU mutant. The bacillus subtilis for high-yield surfactin and the preparation method thereof disclosed by the invention are beneficial to realizing industrial production and commercial application of the surfactin.

The invention relates to a method for increasing the yield of L-malic acid produced by fermentation by adding ethylene glycol, which comprises the following steps: constructing genetic engineering escherichia coli, and introducing ethylene glycol metabolism genes (overexpression) including glycerol dehydrogenase, lactaldehyde reductase, lactaldehyde dehydrogenase and the like; and overexpression of other genes involving malic acid production, such as malic acid synthase, phosphoenolpyruvate carboxylase and malic acid export protein. The gene engineering strain is an E.coli BW25113 strain of which ldhA, pta, poxB, adhE, pflB, mgsA, frdA, maeA, maeB, yqhD, ycdW and iclR genes are substantially inactivated, and the deleted genes are beneficial to reducing the generation of metabolic byproducts and increasing the accumulation of malic acid. The genetic engineering strain is subjected to fermentation culture by taking glucose and ethylene glycol as carbon sources, and L-malic acid is separated from a culture after culture is finished.

The invention belongs to the field of metabolic engineering, and discloses a genetically engineered bacterium of high-yield beta-alanine as well as a construction method and application of the genetically engineered bacterium. The genetically engineered bacterium takes escherichia coli W3110 as an original strain, and is obtained by performing the following gene editing on a genome of the escherichia coli W3110, the genetically engineered bacterium does not express proteins such as lactose operon repressor protein, pyruvate dehydrogenase, acetokinase and the like; protein such as aspartic acid-alpha-decarboxylase, phosphoenolpyruvate carboxylase, pyruvate carboxylase and the like is overexpressed; the phosphoenolpyruvate carboxykinase is replaced by phosphoenolpyruvate carboxykinase from Mannheim succinic acid producing bacteria. The genetically engineered bacterium BA-17 for high yield of beta-alanine, which is constructed by the invention, is fermented in a 5L fermentation tank for 60 hours, the yield of beta-alanine reaches 126.7 g / L, the conversion rate reaches 60.3%, and the production intensity reaches 2.11 g / L / h.

The invention provides a beta-alanine producing strain as well as a construction method and application thereof. According to the bacterial strain, an acetaldehyde dehydrogenase gene adhE, a lactic dehydrogenase gene ldhA, an acetokinase gene ackA, a pyruvate dehydrogenase gene poxB, a DNA binding transcription inhibition factor coding gene lacI, an aspartate kinase thrA, a pantothenic acid synthase gene panC, an alanine synthesis transaminase gene cycA and an alanine synthesis transaminase gene yfbQ are knocked out from an E.coli W3110 genome, and the bacterial strain is obtained. A phosphoenolpyruvate carboxylase gene ppc, a pyridine nucleotide transhydrogenase coding gene pntAB, an aspartic acid transaminase gene aspC, an aspartic acid decarboxylase gene panD derived from pseudomonas aeruginosa and a beta-alanine transporter gene NCgl0580 derived from corynebacterium glutamicum are integrated at the same time, and the bacillus subtilis is used for producing beta-alanine and has the advantage of high fermentation yield.

The invention discloses a rice ACCase mutant protein and a preparation method thereof. The amino acid sequence of the ACCase mutant gene encoding protein has the following mutations: the 2052nd site corresponding to the amino acid sequence of wild rice ACCase is mutated, isoleucine (I) is changed into asparagine (N), or isoleucine (I) is changed into glutamine (Q), or isoleucine (I) is changed into cysteine (C), or isoleucine (I) is changed into cysteine (C), or isoleucine (I) is changed into cysteine (C), or isoleucine (I) is changed into cysteine (C), or isoleucine (I) is changed into cysteine (C). And the plant can have extremely strong resistance (tolerance) to acetyl-coenzyme A carboxylase inhibitor herbicides. After the rice containing the rice ACCase mutant protein disclosed by the invention is applied with an acetyl-coenzyme A carboxylase inhibitor herbicide with 8 times of recommended use concentration, plants still grow normally, and the tolerance of the herbicide is greatly enhanced, so that the rice ACCase mutant protein can be widely applied to breeding of herbicide-resistant plants.

The present invention relates to the field of bioengineering technology and provides a ppc mutant and its application in the fermentative production of L-valine. By performing point mutations on the ppc gene, the expression activity of phosphoenolpyruvate carboxylase is reduced, the competition of the bypass pathway is weakened, the supply of pyruvate precursors is enhanced, and the production capacity and biomass of the valine engineering strain are further improved. It can be seen from the fermentation results that this method can significantly increase the yield of valine, from the original 1.3 g / L to 1.49 g / L, with a 14.6% increase in yield. Therefore, the present invention has application value.

The present application relates to a mutant gene encoding phosphoenolpyruvate carboxylase containing a mutant 5' untranslated region (5'UTR), a polyhydroxyalkanoate (PHA)-producing microorganism containing the gene, and a PHA production method using the same.

The invention discloses bacillus subtilis with high yield of specific surfactin and a preparation method and application thereof, the bacillus subtilis is obtained by a gene modification method and can produce high yield of C15 component surfactin, and the highest yield can reach 72.5%; the invention also provides an enzyme mutant participating in the production of the surfactin from the bacillus subtilis, wherein the enzyme mutant comprises carboxyl transferase accAD, biotin carboxylase IdeHA, biotin carboxylase accBC and fatty acid peroxygenase cypC; in addition, the invention also provides a preparation method and application of the bacillus subtilis. The bacillus subtilis for high-yield production of specific surfactin and the preparation method thereof provided by the invention are beneficial to increase of the yield of surfactin, especially industrial production and commercial application of C15 component surfactin.

The invention belongs to the technical field of biological engineering, and discloses a schizochytrium limacinum engineering strain co-expressing a PDC-ACC gene, a construction method and application, and the genetic engineering strain is obtained by taking schizochytrium limacinum as an original strain and expressing a pyruvate decarboxylase compound gene PDC and an acetyl-coenzyme A carboxylase gene ACC in yarrowia lipolytica. The PDC and ACC genes in the schizochytrium limacinum genetic engineering strain disclosed by the invention are cloned to yarrowia lipolytica, namely Po1f. The yield of traditional fermented grease is 43.90 g / L. The engineering strain performs overexpression on PDC and ACC genes, so that the grease content of the schizochytrium limacinum engineering strain is increased by 53.13% and reaches 67.22 g / L, and the DHA content is increased by 36.97% and is increased from 40.71% to 55.76%.

The invention discloses recombinant escherichia coli capable of increasing the yield of L-homoserine and a preparation method of the recombinant escherichia coli, and belongs to the technical field of biology. By constructing a multi-way glucose transport system, L-homoserine synthesis precursor supply is enhanced, high-energy-consumption genes are knocked out, ATP regeneration is enhanced, ATP availability is improved, an acetic acid conversion way is established, and an L-homoserine degradation way is blocked, so that a metabolic flow of a synthesis way is further enhanced; a pyruvate carboxylase mutant and a designed promoter are introduced to weaken expression of citrate synthase and reconstruct key metabolic nodes, and fed-batch fermentation conditions of the strain in a 5L bioreactor are optimized according to metabolic characteristics of the strain; the genetically engineered bacterium which is clear in genetic background, does not carry plasmids, does not need induction and can stably and efficiently produce the L-homoserine is obtained, the yield of the L-homoserine reaches 141.5 g / L after the L-homoserine is fermented for 56h in a 5L fermentation tank, the saccharic acid conversion rate reaches 40%, and the genetically engineered bacterium has a certain application prospect.

The invention discloses a genetically engineered bacterium for high yield of L-alanine as well as a construction method and application of the genetically engineered bacterium, a dominant strain is obtained by knocking out an alanine racemase gene dadX and integrating coding sequences of alanine dehydrogenase from different sources, and the shake flask yield is 10.8 g / L; the activity of a corresponding mutant M18L / E75A / A78S / I266V is 4.3 times that of a wild type; 6 by-product related genes are knocked out, meanwhile, a multi-copy strain integrated with alanine dehydrogenase is constructed, and the yield of E.coli A-LB6 in a 5L fermentation tank is increased to 133.3 g / L. Through a dynamic regulation and control strategy, an oxygen-sensitive promoter Pomp * is adopted to replace a phosphoenolpyruvate carboxylase promoter, so that succinic acid byproducts are reduced by 85.8%, and the yield reaches 143.5 g / L after 48 hours of aerobic and anaerobic two-stage fermentation. And finally, by regulating and controlling the ATP synthetase gene cluster atp promoter, the yield of L-alanine in a 50 L fermentation tank reaches 151.3 g / L, and the saccharic acid conversion rate reaches 95.2%. The combination of polygene knockout and dynamic metabolism regulation effectively enhances the biosynthesis ability of alanine, and provides an efficient engineering strain for industrial production.

The invention relates to a biomass energy utilization and resource utilization technology, and aims to provide a method for improving the carbon sequestration capability of nannochloropsis oculata by domesticating and regulating a key enzyme with high ammonium salt. The method comprises the following steps: carrying out nitrogen salt gradient domestication on nannochloropsis oculata cells, and regulating and controlling the expression quantity of five key enzymes, namely H < + > transport ATP enzyme, glutamine synthetase, asparagine synthetase, carbonic anhydrase and ribulose-1, 5-diphosphate carboxylase / oxygenase, in the nannochloropsis oculata cells; the domesticated and cultured nannochloropsis oculata can independently use coked ammonium sulfate as a nitrogen source required by growth; the domesticated algal strains are subjected to transfer culture, and verification and screening are carried out aiming at the capability of fixing CO2 in flue gas and the prevention of over-acidification of the culture medium. According to the method, the utilization of coked ammonium sulfate by the nannochloropsis oculata can be enhanced without causing over-acidification of the culture medium, the microalgae culture cost can be effectively saved, and the flue gas CO2 immobilization capability of the nannochloropsis oculata is improved; a new thought is provided for large-scale breeding and cultivation by using coked ammonium sulfate and improvement of economic efficiency.

A method of altering fatty acid and / or triacylglycerol production in plants and / or algae is provided. The method includes altering activity levels of alpha-carboxyltransferase (α-CT), a catalytic subunit of acetyl-CoA carboxylase (ACCase) by modulating an expression of at least one carboxyltransferase interaction (CTI) gene encoding at least one CTI protein.

The present disclosure relates to a genetically modified microorganism satisfying some of predetermined conditions. The predetermined conditions include: (I) succinate dehydrogenase activity or fumarate reductase activity being reduced or inactivated relative to a wild-type microorganism; (II) lactate dehydrogenase activity being reduced or inactivated relative to the wild-type microorganism; (III) the genetically modified microorganism having modified phosphoenolpyruvate carboxylase activity showing resistance to feedback inhibition by aspartic acid in wild-type phosphoenolpyruvate carboxylase activity, or exogenous phosphoenolpyruvate carboxylase activity having higher resistance to feedback inhibition by aspartic acid than that of the wild-type phosphoenolpyruvate carboxylase activity shown by the wild-type microorganism; and (IV) pyruvate:quinone oxidoreductase being reduced or inactivated relative to the wild-type microorganism.

The application provides a recombinant Yarrowia lipolytica capable of producing palmitoleic acid at a high yield, a construction method and application thereof, and belongs to the technical field of bioengineering. Yarrowia lipolytica The recombinant Yarrowia lipolytica is obtained by knocking out peroxisome biogenesis factor 10 and triacylglycerol lipase 4 in the genome of Yarrowia lipolytica and inserting an acetyl-CoA carboxylase, a Δ9 desaturase, an acetyl-CoA diacylglycerol acyltransferase, a glycerol-3-phosphate acyltransferase, a lysophosphatidylcholine acyltransferase and a phosphatidylcholine:diacylglycerol acyltransferase gene expression cassette. Experiment proves that the recombinant Yarrowia lipolytica can efficiently ferment and produce palmitoleic acid, and realizes efficient synthesis of the natural product palmitoleic acid from plants in Yarrowia lipolytica.

The present invention provides a mutant acetyl-CoA carboxylase (ACC) protein, a nucleic acid and an application thereof, and in particular, relates to a mutant acetyl-CoA carboxylase (ACC) protein, a nucleic acid and an application thereof in plant breeding. In particular, the present invention provides a mutant acetyl-CoA carboxylase (ACC) protein, and the mutant acetyl-CoA carboxylase (ACC) protein is compared with the parent acetyl-CoA carboxylase (ACC) protein in the region corresponding to SEQ ID Mutations occur at any one or several of the following amino acid positions in the amino acid sequence shown in No. 1: 2125, 2097, 2139, 2194, 2186, 2273, 2168, 1975, 1954, 1864, 2211, 2187, 2123, and 2126; plants with the acetyl-CoA carboxylase (ACC) mutation have high herbicide resistance and have very broad application prospects in breeding herbicide-resistant plants.

The application belongs to the field of biological analysis, and provides a method for precise metabolic flow analysis of TCA cycle based on isotope tracing technology combined with high-resolution mass spectrometry. By optimizing mass spectrometry parameters and liquid chromatography method, one injection within 6 min is realized, and high-throughput, high-sensitivity and high-resolution detection is realized on 11 biomarkers related to TCA cycle metabolic pathways. At the same time, the application innovatively uses LC-MS / MS to decipher 13 C the stepwise position-specific transfer from glucose to subsequent metabolites by glycolysis and TCA cycle, thereby calculating 13 C the integrated steady-state analysis of key metabolic rates of position-specific transfer from sequential precursors to their products (pyruvate dehydrogenase, beta-oxidation, pyruvate carboxylase, isocitrate dehydrogenase and pyruvate cycle). This technology has wide applicability and can potentially characterize mitochondrial metabolism of any tissue or cell.

The invention belongs to the technical field of biological engineering, and particularly relates to a construction method and application of yeast engineering bacteria for producing 1-aminocyclopropane-1-carboxylic acid (ACC). Pyruvate carboxylase gene RoPYC, yeast SAM enzyme gene Sam2 and ACS synthase gene GmACS are overexpressed in saccharomyces cerevisiae, so that the 1-aminocyclopropane-1-carboxylic acid (ACC) is obtained; a path for biosynthesizing 1-aminocyclopropane-1-carboxylic acid (ACC) by taking glucose as a substrate is designed, a saccharomyces cerevisiae engineering bacterium for producing ACC is constructed, the ACC can be produced by large-scale fermentation, and the highest yield can reach 50.56 g / L. The method has the advantages of low environmental influence, easiness in large-scale production expansion, high production efficiency and the like, has a good economic prospect, and lays a foundation for artificial efficient biosynthesis of ACC.

The present application relates to the field of plant genetic breeding, and particularly relates to a kind of evaluation method of asparagus yield. Including the following steps: S1, obtaining young plant period asparagus;S2, measures i variety of young plant period asparagus following parameters: photosynthetic rate A, ribulose-1,5-bisphosphate carboxylase / oxygenase activity B, leaf dry weight per unit area C, acid invertase activity D and root crown ratio E;The measurement sample of the acid invertase activity D is the tender stem of young plant period asparagus at 10-30cm from top;S3, according to the formula, the evaluation value is calculated, and the evaluation value is used to evaluate the yield of asparagus. The evaluation value obtained by using the above measurement index and calculation formula, and the significance level obtained by SPSS software is used to evaluate the yield of asparagus. The yield potential of asparagus can be comprehensively evaluated from the genetic point of view in a short time. Using the evaluation method of the present application, high-yield asparagus varieties can be selected in a short time without tracking for many years.

The invention relates to the technical field of substance detection, and particularly discloses an enzyme activity determination method of acetyl-CoA carboxylase, a kit and application. The invention provides an enzyme activity determination method of acetyl coenzyme A carboxylase. The detection reaction process is as follows: # imgabs0 #. The detection method provided by the invention can realize rapid and accurate detection of ACC enzyme activity, can perform efficient ACC determination in research and application, and has a wide application prospect.

This invention aims to create a spatially isolated local reaction microenvironment for Rubisco by introducing a complete β-carboxysome microcompartment system. This design goal avoids oxygen inhibition, laying the foundation for ultimately achieving efficient and specific CO2 fixation. It provides a novel approach to overcome the fundamental problem of low efficiency of carbon-fixing enzymes in cytosols due to intense oxygen competition. By introducing the complete carboxysome system as a module, engineered yeast strains with high carboxylase activity and significantly improved ethanol production were obtained, providing a solid foundation for building next-generation yeast cell factories that produce high-yield ethanol using CO2 as a raw material.

Herein is reported a method for producing C-terminally biotinylated FcRn comprising the steps of cultivating a mammalian cell comprising a deoxyribonucleic acid encoding FcRn and E. coli biotin-[acetyl-CoA-carboxylase] ligase (BirA) in a biotin containing medium, and recovering C-terminally biotinylated FcRn from the cell or the cultivation medium, wherein the deoxyribonucleic acid encoding FcRn and E. coli BirA is stably integrated into the genome of the mammalian cell and comprises in 5′- to 3′-direction a first expression cassette encoding class I major histocompatibility complex-like protein (α-FcRn) comprising a HisAvi-tag at the C-terminus, a second expression cassette encoding β2-microglobulin (β2m), a third expression cassette encoding class I major histocompatibility complex-like protein (α-FcRn) comprising a HisAvi-tag at the C-terminus, a fourth expression cassette encoding β2-microglobulin (β2m), and a fifth expression cassette encoding E. coli biotin-[acetyl-CoA-carboxylase] ligase.

The invention discloses a recombinant bacterium for producing mevalonic acid by taking glucose and acetone as co-substrates as well as a construction method and application of the recombinant bacterium, and belongs to the technical field of genetic engineering. The problems that an existing mevalonic acid biosynthesis mode is low in carbon atom economy, limited in theoretical yield and the like are solved. According to the invention, acetone carboxylase, acetoacetyl coenzyme A synthetase, 3-hydroxy-3-methylglutaryl coenzyme A reductase and hydroxymethyl glutaryl-CoA synthetase are subjected to heterologous expression in escherichia coli with an acetyl coenzyme A acetyltransferase gene atoB and a histidine protein kinase gene atoS knocked out, and self carbonic anhydrase is over-expressed; and a new way for synthesizing MVA by using glucose and acetone as a co-substrate is constructed. According to the method, one molecule of CO2 can be fixed in the biosynthesis of mevalonic acid, the yield of carbon atoms in the synthesis process of mevalonic acid is increased, the problem of low yield of carbon atoms in the synthesis process of mevalonic acid by taking glucose as a single substrate is solved, and a new thought is provided for constructing a carbon neutralization type biological manufacturing technology.

The invention provides recombinant Escherichia coli for synthesizing heme and derivatives thereof, and the recombinant Escherichia coli is used for knocking out genes such as pyruvate oxidase poxB, pyruvate formate lyase pflB and porphyrinoperoxidase yfeX and enhancing genes such as phosphoenolpyruvate carboxylase ppc, glycerol transporter glpF and 3-phosphoglycerol dehydrogenase glpD, so that the heme and the derivatives thereof can be synthesized. After genes such as exogenous 5-aminolevulinic acid synthase hemA and ferrous chelating enzyme hemH are introduced, the heme and the derivatives thereof can be synthesized by taking glycerol as a raw material, and the heme has an application prospect in the field of biological manufacturing.

The invention discloses a compound enzyme preparation-containing nutritional feed for regulating and controlling intramuscular fat of black pigs and a preparation method of the compound enzyme preparation-containing nutritional feed, and relates to the technical field of livestock and poultry breeding feeds. The invention discloses a black pig skeletal muscle cell fat directional transport feed which is prepared from the following components in parts by weight: 850-920 parts of basal feed, 5-12 parts of fat directional deposition compound enzyme group, 25-40 parts of amino acid-enzymatic synthesis substrate combination and 2-6 parts of lipolytic enzyme specific inhibitor. According to the black pig skeletal muscle cell fat directional transport feed, fat precursor directional transport is realized through the compounded fat directional deposition compound enzyme group, a fat synthesis pathway targeting black pig skeletal muscle cells and lipoprotein lipase; acetyl-coenzyme A carboxylase and fatty acid synthetase catalyze fat synthesis step by step, only intramuscular fat generation pathways are activated, subcutaneous and abdominal fat deposition paths are blocked, the technical defects that fat deposition of an existing single enzyme preparation is non-directional, and the body fat rate is caused to be abnormally increased are overcome, meanwhile, an exclusive amino acid-enzymatic synthesis substrate combination is matched, and the body fat synthesis efficiency is improved. Sufficient adaptive substrates are supplied to enzyme group catalytic reaction, and the problem that a single enzyme preparation is insufficient in catalytic efficiency is solved.

This invention provides an engineered bacterium for producing ectoine, its preparation method, and its application. The engineered bacterium is prepared using a method comprising the following steps: using *Corynebacterium glutamicum* as the starting strain, feedback inhibition by aspartate kinase LysC is relieved, the activity of the gene lysE encoding lysine efflux permease is reduced, and the ectoine synthesis gene cluster ectABC is expressed. Based on this, the activity of any one or at least two of the following—diaminobutyrate acetyltransferase EctA, pyruvate carboxylase Pyc, or aspartate kinase LysC—is enhanced, and / or the activity of any one or at least two of the following—maloquinone oxidoreductase Mqo or homoserine dehydrogenase Hom—is reduced to further increase ectoine yield.

The present invention provides a class of new mutant proteins for increasing malic acid yield. Specifically, the present invention provides a class of new pyruvate carboxylase mutant protein and malic acid transporter mutant proteins or combinations thereof, a preparation method therefor and use thereof in improving malic acid yield.

Disclosed are genetically engineered Schizosaccharomyces pombe strains capable of fermenting glucose to produce malic acid. The S. pombe strains produce an exogenous malate dehydrogenase (MDH) enzyme and optionally produce an exogenous pyruvate carboxylase (PYC) enzyme or an exogenous phosphoenolpyruvate carboxylase (PPC) enzyme. Additionally, the S. pombe strains may be further engineered to produce a fumarase selectively located in mitochondria and / or have an inactivated mitochondrial citrate transporter, so that the resulting S. pombe strains are capable of producing malic acid as the predominant C4 dicarboxylic acid. Also disclosed are methods of producing malic acid with the S. pombe strains.

The invention provides an application of a CsPPC3 gene in regulation and control of carbon and nitrogen metabolism of cucumber fruits, a major gene CsPPC3 for coding phosphoenolpyruvate carboxylase (PEPC) in carbon fixation of the cucumber fruits is taken as a research target, an overexpression and gene knockout transgenic plant is constructed, the effect of the CsPPC3 gene in carbon fixation and carbon and nitrogen metabolism of photosynthesis of the fruits is researched, and the CsPPC3 gene is applied to regulation and control of carbon and nitrogen metabolism of the cucumber fruits. It is found that the amount of CO2 released by respiration of a transgenic plant overexpressed by the CsPPC3 gene is reduced, the CO2 refixation capacity is enhanced, the single fruit weight of the fruit is increased, the content of malic acid, soluble sugar and starch is increased, and the content of amino acid is reduced, while the amount of CO2 released by respiration of a transgenic plant knocked out by the CsPPC3 gene is increased, and the single fruit weight of the fruit is reduced. Meanwhile, the contents of malic acid, soluble sugar and amino acid are reduced, the starch content is increased, and the CO2 refixing capacity is reduced. The method disclosed by the invention has practical guiding significance for cultivating transgenic plants with high CO2 fixing efficiency.