52 results about "Isomerase Gene" patented technology

The invention discloses a recombinant strain for producing squalene as well as a construction method and application of the recombinant strain. The construction method comprises the following steps: heterologously expressing cDNA (complementary deoxyribonucleic acid) of each gene in a squalene synthesis route from filamentous fungi in yeast; the squalene synthetic pathway genes comprise a mevalonic acid-5-phosphate kinase gene, a squalene synthase gene, an acetoacetyl coenzyme A thiolase gene, a mevalonic acid kinase gene, a hydroxymethyl glutaryl coenzyme a synthetase gene, a mevalonic acid pyrophosphate decarboxylase gene, a farnesyl pyrophosphate synthetase gene and isopentenyl pyrophosphate. A dimethallylpyrophosphate isomerase gene and a truncated hydroxymethyl glutaryl coenzyme a reductase gene; the culture medium is characterized in that the filamentous fungi are Saroocladium oryzae or Stibella sp. 1056, and the culture medium is a culture medium. The excavated squalene synthesis route can complete efficient de novo synthesis of squalene, and the squalene yield is increased.

The method for preparing D-mannose through catalysis can effectively reduce the amount of by-products glucose and fructose, and greatly improves the conversion rate of D-mannose. Specifically, engineering bacteria for expressing isoamylase genes and engineering bacteria for expressing alpha-glucan phosphorylase genes, glucophosphate mutase genes, difunctional enzyme glucophosphate isomerase / mannose 6-phosphate isomerase genes and mannose 6-phosphate phosphatase genes are utilized, starch or starch derivatives are used as substrates, and the starch or starch derivatives are used as substrates. A phosphate buffer solution and Mg < 2 + > are added, a preliminary catalysis system is constructed, after the reaction is completed, an incompletely-reacted substrate and maltodisaccharide exist in the reaction system, the incompletely-reacted substrate and maltodisaccharide can be hydrolyzed into glucose by glucoamylase, and the polyphosphoglucokinase can be used for catalyzing the reaction of the polyphosphoglucokinase under the assistance of sodium hexametaphosphate. All glucose is converted into phosphorylated glucose, then D-mannose is generated, and by-products in a system are removed while the yield is increased.

Engineering bacteria for expressing an alpha-glucose phosphate mutase gene, a glucose phosphate mutase gene, a difunctional enzyme glucose phosphate isomerase / mannose 6-phosphate isomerase gene and a mannose 6-phosphate phosphatase gene are used as a whole-cell catalyst, starch or a starch derivative is used as a substrate, phosphate and Mg < 2 + > are added, and the whole-cell engineering bacteria are obtained. A whole-cell catalysis system is constructed, and starch or starch derivatives can be efficiently catalyzed to synthesize D-mannose. According to the method, the D-mannose is prepared through whole-cell catalysis, and the method has the advantages of being low in cost, low in pollution, high in yield and the like and is suitable for industrial production of the D-mannose.

The invention provides a method for synthesizing D-psicose through fermentation of escherichia coli by using D-glucose and D-xylose. The method comprises the following steps: by taking escherichia coli as a host cell, over-expressing a galactose permease gene galP, a glucokinase gene glk, a 6-phosphate glucose isomerase gene pgi, a D-psicose-6-phosphate epimerase gene alsE with an SUMO tag and a D-psicose-6-phosphate phosphatase gene a6PP, and constructing a path for synthesizing D-psicose by taking D-glucose and D-xylose as substrates; the synthetic route of D-psicose is optimized by knocking out a D-glucose phosphorylation transport pathway gene ptsG, knocking out D-fructose-6-phosphokinase genes pfkA and pfkB, silencing a glucose-6-phosphate dehydrogenase gene zwf, overexpressing glutamate transhydrogenase genes gdh1 and gdh2, knocking out a UDP-glucose-4-epimerase gene galE and knocking out a transport protein key gene fryA in D-psicose; and finally, the optimal proportion of mixed sugar fermentation is explored, so that efficient synthesis of D-psicose from escherichia coli through mixed sugar fermentation of D-glucose and D-xylose is realized.

The invention belongs to the technical field of biotechnology and biocatalysis, and particularly relates to a method for preparing D-tagatose by catalyzing isomerization of D-fructose. The invention provides a method for preparing D-tagatose by catalyzing isomerization of D-fructose, which comprises the following steps: by taking a wet cell obtained by inducible expression of a recombinant genetically engineered bacterium containing a D-tagatose-4-epimerase gene as a catalyst and D-fructose as a substrate, when the concentration of the substrate is higher than 300g / L, continuously supplementing the substrate and enzyme to prepare the D-tagatose by adopting a strategy of continuously supplementing the substrate and enzyme. The substrate inhibition is reduced, the conversion rate of the D-tagatose is increased, and the final conversion rate of the D-tagatose is increased from 19.5% to 24.2%.

The invention belongs to the field of gene engineering, and particularly relates to application of a willow uridine diphosphate glucose-4-epimerase gene SpUGE1 in plant cell wall component remodeling, organelle cadmium content reduction and cadmium resistance improvement. According to the invention, the SpUGE1 gene in willow is extracted, and is transferred into arabidopsis thaliana by constructing a recombinant plasmid, so that the biological activity, Cd < 2 + > concentration and the like of wild arabidopsis thaliana and transgenic arabidopsis thaliana are compared. The result of the embodiment shows that the transgenic arabidopsis thaliana has certain tolerance to cadmium stress, the cell wall of the transgenic arabidopsis thaliana is obviously thickened, and the content of cadmium in organelles is obviously reduced.

The invention discloses recombinant escherichia coli with high yield of N-acetylneuraminic acid and application of the recombinant escherichia coli, and relates to the technical field of biological genetic engineering. The invention relates to a recombinant escherichia coli, which is characterized in that the escherichia coli is taken as a host, and free expression of an N-acetylmannosamine epimerase gene yihS from Streptomyces xiamenensis or an N-acetylmannosamine epimerase gene ce3 from Bacteroides polymorpha and an exogenous N-acetylneuraminic acid lyase gene nano A is carried out; and carrying out recombinant expression on N-acetyl hexosamine 1-kinase nahK, a UDP-N-acetyl glucosamine pyrophosphorylase gene glmU and a UDP-N-acetyl glucosamine-2-epimerase gene neuC in the other synthetic route of the ManNAc. According to the recombinant escherichia coli with high yield of N-acetylneuraminic acid, the yield of N-acetylneuraminic acid can reach 23.08 g / L under a shake flask fermentation condition; a two-stage batch feeding strategy is adopted, the yield of N-acetylneuraminic acid in a 5L fermentation tank reaches 71.25 g / L, the molar conversion rate of GlcNAc reaches up to 57.60%, and the method has the potential of industrial application.

The invention relates to the technical field of plant genetic engineering, and particularly discloses a construction method of a VIGS silencing system for agastache rugosus gene function research, which comprises the following steps: constructing a TRV2-PDS or TRV2-CHLH visual vector by taking indicator genes PDS and CHLH for chlorophyll synthesis as reporter genes; the method comprises the following steps: transforming a TRV2-PDS or TRV2-CHLH visual vector into agrobacterium, and performing injection infection on cotyledons of a target plant to construct a VIGS silencing system. According to the invention, cloning, amplification and vector construction are carried out on the isopuleone isomerase gene (ArIPI gene) in the agastache rugosus, and the function of the ArIPI gene is verified in a plant body, so that a scientific basis is provided for improving and cultivating the agastache rugosus and constructing genetic engineering.

The invention discloses a Zymomonas mobilis recombinant strain for producing D-pantothenic acid as well as a preparation method and application of the Zymomonas mobilis recombinant strain. A hydroxymethyl transferase gene panB, a ketopantoic acid reductase gene panE and a pantothenic acid synthase gene panC are integrated in a genome of the recombinant strain; an expression plasmid containing an acetolactate synthase gene Bsals, a keto acid reductoisomerase gene ilvC and a dihydroxy acid dehydratase gene ilvD is also transferred into the recombinant strain; wherein the nucleotide sequences of the gene Bsals, the gene ilvC, the gene ilvD, the gene panB, the gene panE and the gene panC are shown as SEQ ID NO. 1 to SEQ ID NO. 6 in sequence. The zymomonas mobilis ZM4 is systematically modified through a genetic engineering means, and an optimal enzyme combination adaptive to the zymomonas mobilis is defined by screening hydroxymethyltransferase, pantothenic acid synthase and ketopantoic acid reductase from different sources, so that a core foundation is laid for efficient operation of a D-pantothenic acid synthesis route, and the method has a wide application prospect. The technical bottlenecks of single metabolic pathway and low synthesis efficiency of the traditional strain are broken through.

The invention provides a group of recombinant Escherichia coli for forming D-psicose. The recombinant Escherichia coli comprises the following multiple modifications: (a) introducing and expressing a dTDP-glucose-3-epimerase gene, an NDP glycohydrolase gene, an allose-1 phosphate-isomerase gene and an acid phosphatase gene; and (b) enhancing the expression of the glucose phosphate mutase gene, the expression of the glucose 1-phosphate thymine transferase 1 gene and the expression of the glucose 1-phosphate thymine transferase 2 gene. The recombinant Escherichia coli capable of producing D-psicose at high yield is prepared, the yield of by-products is reduced while the yield of a target object is increased, the bottleneck problem in industrial production is solved, and the recombinant Escherichia coli can be used for mass production of D-psicose.

The invention discloses an N-acetyl glucosamine 2-epimerase mutant as well as preparation and application of the N-acetyl glucosamine 2-epimerase mutant. The mutant enzyme comprises an amino acid sequence as shown in SEQ ID No.3. The preparation method comprises the following steps: by taking a recombinant vector containing a Sumo enhancing element and a wild type N-acetyl glucosamine 2-epimerase gene as a template, carrying out PCR (Polymerase Chain Reaction) by adopting a mutation primer to obtain a mutant gene segment; transforming the mutant gene segment into an engineering bacterium to obtain a recombinant bacterium for expressing the N-acetyl glucosamine 2-epimerase mutant protein; culturing recombinant bacteria, collecting and crushing thalli, centrifuging thallus crushing liquid, and taking supernatant, so as to obtain crude enzyme liquid containing the enzyme mutant; the thermal stability of the wild-type enzyme is improved through point mutation of specific amino acid sites, and the substrate affinity and the catalytic efficiency of the mutant are superior to those of the wild-type enzyme. The mutant can be used for efficient catalytic preparation of lactulose, and has the advantages of few byproducts, high product yield and the like.

The method for catalytically preparing D-mannose provided in the application can effectively reduce the amount of by-products glucose and fructose, and greatly improve the conversion rate of D-mannose. Specifically, the engineering bacteria expressing isoamylase gene and the engineering bacteria expressing alpha-glucan phosphorylase gene, glucose phosphomutase gene, bifunctional enzyme glucose phosphate isomerase / mannose 6-phosphate isomerase gene and mannose 6-phosphate phosphatase gene are used, starch or starch derivatives are used as substrates, phosphate buffer solution and Mg 2+ A preliminary catalytic system is constructed, and after the reaction is completed, there are unreacted substrates and maltodextrin in the reaction system, the saccharifying enzyme can hydrolyze the unreacted substrates and maltodextrin into glucose, the polyphosphate glucose kinase can convert all the glucose into phosphorylated glucose with the assistance of sodium hexametaphosphate, and then D-mannose is generated, thereby improving the yield and removing the by-products in the system.

The invention discloses a recombinant microorganism for producing alpha-ketoisovaleric acid as well as a preparation method and application of the recombinant microorganism. The recombinant microorganism for producing alpha-ketoisovaleric acid, disclosed by the invention, has the following characteristics: the recombinant microorganism contains a substance capable of expressing an acetolactate synthase gene and / or a substance capable of promoting the expression of the acetolactate synthase gene and / or a substance capable of improving the activity or content of acetolactate synthase; the composition contains a substance capable of expressing an acetohydroxy acid reductoisomerase gene and / or a substance capable of promoting the expression of the acetohydroxy acid reductoisomerase gene and / or a substance capable of improving the activity or content of acetohydroxy acid reductoisomerase; the composition contains a substance capable of expressing a dihydroxy acid dehydratase gene and / or a substance capable of promoting the expression of the dihydroxy acid dehydratase gene and / or a substance capable of improving the activity or content of the dihydroxy acid dehydratase. Experiments prove that the recombinant microorganism disclosed by the invention can be used for producing alpha-ketoisovaleric acid by utilizing glucose and has a very good application prospect.

The present invention belongs to the field of microbial technology, and relates to a genetically engineered bacterium for preparing ethanol based on hydrolyzed sugar from wood fiber and its application. The bacterium is a high xylose utilization and inhibitor tolerance engineered bacterium. The engineered bacterium is based on Saccharomyces cerevisiae S288C as a chassis strain, and co-expresses heterologous xylose reductase-xylitol dehydrogenase pathway-related genes, xylose transport-related genes, xylose isomerase-related genes and xylose isomerase genes, and over-expresses endogenous xylulose kinase-related genes, non-oxidative pentose phosphate pathway-related genes, reduced glutathione system genes, superoxide dismutase expression system-related genes, NADPH / NADP + The genes and transcription factors related to the cofactor circulation system were knocked out, the genes related to the competitive metabolic pathway were knocked out, and the bacteria were domesticated with sugar sources and inhibitors as pressure; the engineered bacteria can efficiently metabolize xylose and produce high-concentration ethanol in non-detoxified lignocellulose hydrolysate with high inhibitor concentrations and without any nutrient salt addition.

The invention relates to the field of bioengineering and genetic engineering, and particularly provides a rapid digging method of isomerase genes. According to the method, on the basis of big data analysis and bioinformatics technologies, in combination with means of sequence alignment, gene expression analysis, function prediction and the like, rapid and accurate mining of isomerase genes is achieved, and powerful technical support is provided for development and application of the enzyme engineering field.

The invention belongs to the technical field of plant disease prevention and treatment, and relates to application of an alternaria alternate nucleoside diphosphate sugar isomerase gene in prevention and treatment of allium tuberosum leukoderma. The invention provides a dsRNA (double-stranded ribonucleic acid) preparation taking an alternaria alternate nucleoside diphosphate glycoisomerase gene as a target and application of the dsRNA preparation in prevention and control of allium tuberosum leukoplakia. Normal transcription expression of the alternaria alternate nucleoside diphosphate glycoisomerase gene is interfered by dsRNA, so that influence on mycelial growth, spore production rate and the like of alternaria alternate can be realized; and the alternaria alternata can be used for green prevention and control of the white spot disease of the Chinese chives, and is high in pertinence and good in prevention and control effect. Meanwhile, pollution of chemical agents to the environment can be reduced by using the dsRNA preparation, the safety is high, and the application range is wide.

The invention discloses a genetically engineered bacterium for biosynthesis of inositol and application of the genetically engineered bacterium for biosynthesis of inositol, and the genetically engineered bacterium for biosynthesis of inositol is obtained by co-expressing a sweet orange inositol-3-phosphate synthase gene Csino3 and an escherichia coli inositol-1-monophosphate gene suhB in recombinant escherichia coli and then knocking out a glucose phosphate isomerase gene pgi. According to the technical scheme, the yield of inositol produced by the strain reaches 2.04 g / L and is increased by about 6.6 times compared with that before optimization, the inositol yield is greatly increased, the metabolic flux of glycolysis to glucose-6-phosphoric acid is effectively blocked, carbon metabolic flux is forced to be redirected to a pentose phosphate pathway, glucose-6-phosphoric acid is enriched, and a raw material is provided for inositol production. By blocking downstream branches of a glycometabolism pathway, enrichment of glucose-6-phosphate in cells is realized, so that sufficient precursor substances are provided for synthesis of inositol, and finally the yield of inositol is increased. The technical scheme is expected to be applied to construction of microbial cell factories, so that large-scale and low-cost production of inositol is realized, and theoretical support is provided for development of related industries.

The invention provides a strain for producing beta-carotene as well as a construction method and application of the strain, and belongs to the technical field of synthetic biology and genetic engineering. The construction method of the MYy107 strain disclosed by the invention comprises the following steps: step 1, integrating a mevalonate kinase gene ERG12, a phosphomevalonate kinase gene ERG8, a mevalonate diphosphate decarboxylase gene ERG19 and an isopentene diphosphate isomerase gene IDI1 on an RT08 bacterium, so as to obtain an RT10 strain; 2, a xylose reductase gene XYL1, a xylitol dehydrogenase gene XYL2, a xylose isomerase mutant XylA3 * and a xylulokinase gene Yl.Xk are integrated on the RT10 strain, and the MYy107 strain is obtained. According to the MYy107 strain constructed by the invention, the beta-carotene can be produced by using xylose and acetic acid at the same time, and the yield of the beta-carotene is remarkably improved and reaches 710.01 mg / L.

The invention relates to an aerobic methanophilic engineering bacterium for producing taxadiene as well as a construction method and application of the aerobic methanophilic engineering bacterium. A strong promoter P16200 is used for expressing a taxadiene synthase gene TXS in host bacteria; 1-deoxy-xylulose-5-phosphate synthase genes dxs1 and dxs2, geranyl pyrophosphate synthase gene ispA and isopentenyl pyrophosphate isomerase gene Bsidi from bacillus subtilis in a taxadiene synthesis route are overexpressed, the metabolic flux of the route in which a target product is located is improved, meanwhile, 6-glucose phosphate dehydrogenase zwf1 is overexpressed, supply of NADPH (nicotinamide adenine dinucleotide phosphate) is enhanced, and the yield of the target product is increased. Therefore, the material flow and the reducing power are synergistically enhanced; bioconversion from methane to taxadiene is achieved for the first time, the yield of the taxadiene of the constructed engineering methanophilic bacteria is obviously increased, the engineering methanophilic bacteria have industrial application prospects, and a new way is provided for efficient synthesis of terpenoids.

The present application relates to the field of bioengineering, and particularly provides a epimerase Epi20 gene, the sequence of the gene is shown as SEQ NO:1, the enzyme can effectively utilize cucurbitacin 6a to synthesize cucurbitacin 6d, and provides a source for cucurbitacin production.

The invention relates to a recombinant pichia pastoris strain for producing coupled xylitol by NADPH (nicotinamide adenine dinucleotide phosphate) dependent growth and a construction method of the recombinant pichia pastoris strain, and belongs to the technical field of microbial fermentation. The recombinant pichia pastoris strain provided by the invention contains an NADPH dependent xylitol dehydrogenase gene, a sugar phosphatase gene, a D-arabinol-4-dehydrogenase gene, a fructose-1, 3, 4-triazole-1, 3, 4-triazole-1, 3-triazole-1, 3-triazole-1, 3-triazole-1, 3- The gene sequence is as follows: a 1, 6-diphosphatase gene, a phosphoketolase gene, a phosphate transacetylase gene, a glucose-6-phosphate dehydrogenase gene, a 6-phosphogluconolactonase gene, a 6-phosphogluconate dehydrogenase gene and a ribulose-5-phosphate epimerase gene; gene for expressing xylulokinase is knocked out or down-regulated: NADH dependent type xylitol dehydrogenase gene, ribose-5-phosphate isomerase gene, glutamate dehydrogenase gene, phosphofructokinase gene and phosphoglucose isomerase gene. The yield of xylitol produced by fermentation of the strain is far higher than that in the prior art.

The application discloses a platycodon grandiflorum phosphoglucoisomerase gene PgGPI and an application of a product coded by the platycodon grandiflorum phosphoglucoisomerase gene PgGPI, and belongs to the technical field of platycodon grandiflorum genes. The platycodon grandiflorum phosphoglucoisomerase gene PgGPI is cloned from the platycodon grandiflorum, and a nucleotide sequence of the platycodon grandiflorum phosphoglucoisomerase gene PgGPI is shown as SEQ ID NO. 1. The PgGPI gene is successfully expressed in Escherichia coli, and it is verified through an enzymatic experiment that the PgGPI has catalytic activity and can effectively isomerize glucose-6-phosphate into fructose-6-phosphate, thereby laying a solid foundation for further exploring a biosynthesis mechanism of the platycodon grandiflorum polysaccharide. In addition, by means of the PgGPI gene and gene engineering technology, it is expected to significantly improve the content of the polysaccharide substance in the platycodon grandiflorum.

The application belongs to the technical field of genetic engineering and enzyme engineering, and discloses a D-psicose-3-epimerase mutant, which is obtained by performing point mutation on one site in the 79th, 115th, 141st, 193rd or 202nd amino acid of a D-psicose-3-epimerase parent; specifically, a mutation primer for point mutation is designed, a vector carrying a wild-type D-psicose-3-epimerase gene is used as a template to perform point mutation and construct a plasmid vector containing the mutant, and then the plasmid vector is transformed into a host cell to obtain the D-psicose-3-epimerase mutant; and the D-psicose-3-epimerase mutant is applied to the production of psicose. The thermal stability and catalytic activity of the D-psicose-3-epimerase mutant are significantly improved, and the D-psicose-3-epimerase mutant has good industrial application value.

The invention discloses an engineering strain for efficiently producing D-pantothenic acid as well as a construction method and application of the engineering strain, and belongs to the technical field of gene engineering. In the engineering strain, an acetolactate synthase gene alsS *, a keto acid reductoisomerase gene ilvCV412A, a dihydroxy acid dehydratase gene ilvD and other genes are over-expressed; a pantothenic acid kinase gene coAR106A and a phosphoribose enzyme gene prk are expressed; according to the engineering strain, a repressor protein gene lacI, a threonine dehydratase gene ilvA, a pantothenate kinase gene coA and a formate acetyl transferase gene pflD are deleted on a genome. The engineering strain can be used for efficiently synthesizing D-pantothenic acid by taking glucose as a carbon source.

The invention discloses a maleate isomerase mutant and application of the maleate isomerase mutant in preparation of fumaric acid, and relates to the field of bioengineering. The nucleic acid molecule for preparing fumaric acid provided by the invention encodes a maleate isomerase mutant, and the base sequence of the maleate isomerase mutant is shown as SEQ ID NO.4 and SEQ ID NO.6; a recombinant engineering bacterium for converting the nucleic acid molecule can be used as a catalyst for catalyzing a maleic acid substrate to form fumaric acid; according to the method for preparing fumaric acid by using the maleate isomerase engineering bacteria, provided by the invention, the engineering bacteria containing the maleate isomerase gene is used as a catalyst to catalyze maleic acid conversion to obtain fumaric acid, and the fumaric acid has good stability and very high catalytic activity and is environment-friendly in the production process.

The invention provides an engineering bacterium for producing D-pantothenic acid as well as a construction method and application of the engineering bacterium. The engineering bacterium expresses an acetolactate synthase large subunit gene ilv2, an acetolactate synthase small subunit gene ilv6, a keto acid reductoisomerase gene ilvC, a dihydroxy acid dehydratase gene ilvD, a hydroxymethyltransferase gene ecm31, a keto pantoic acid reductase gene panE, an L-aspartic acid decarboxylase gene panD and a pantothenic acid synthase gene panC. According to the method, mitochondria is selected as a targeting compartment, and modular combination optimization approach positioning is adopted, so that the yield of D-pantothenic acid is greatly increased, compared with the yield of an original strain without spatial tissue optimization, the yield is increased by more than one time, the metabolic flux bottleneck in a traditional cytoplasm synthesis mode is broken through, and efficient synthesis of D-pantothenic acid is realized.

The present application relates to the field of bioengineering and genetic engineering, and particularly provides a rapid mining method of isomerase genes. The method is based on big data analysis and bioinformatics technology, combined with sequence alignment, gene expression analysis and function prediction, etc. means, realizes the rapid and accurate mining of isomerase genes, and provides strong technical support for the development and application of enzyme engineering field.

The present invention aims to provide a kelp mannuronic acid C5 isomerase gene and its application in the synthesis of alginate. The amino acid sequence of the kelp mannuronic acid C5 isomerase provided is SEQ ID NO: 1. The kelp MC5E protein of the present invention can be soluble expressed in a prokaryotic expression system, and can convert β-D-mannuronic acid (M) into α-L-guluronic acid (G) at the level of polymer polyM. The conversion efficiency is improved, and the content of G residues in the reaction product is increased, so as to synthesize alginate with higher hardness.

The application provides a saccharomyces cerevisiae engineering bacterium for producing squalene through endogenous and artificial synthetic pathways and an application thereof, the saccharomyces cerevisiae engineering bacterium takes ZS00 strain as a starting strain, overexpresses acetyl coenzyme A acetyltransferase gene, hydroxymethylglutaryl coenzyme A synthase gene and N-terminal truncated hydroxymethylglutaryl coenzyme A reductase gene, and effectively improves the yield of squalene. Heterologous expression of mevalonate kinase gene and mevalonate pyrophosphate decarboxylase gene, overexpression of the key gene squalene synthase gene for promoting the conversion of precursors into squalene effectively promotes the synthesis of squalene. The introduction of isopentenol utilization pathway genes and their mutants, through the regulation of IU pathway key substrate, overexpression of isopentenyl pyrophosphate isomerase gene and farnesyl pyrophosphate synthase gene, the final strain can effectively accumulate squalene to 687.93 mg / L. The application realizes the breakthrough of squalene yield and efficiency through complementation and synergistic effect.

The invention discloses a construction method and application of yarrowia lipolytica engineering bacteria for high yield of itaconic acid, and the construction method comprises the following steps: step S1, by utilizing a CRISPR / Cas9 technology and combining a multi-copy insertion strategy, carrying out precise integration on a citrate lyase gene, a cis-aconitic acid synthetase gene and an itaconic acid synthetase gene, optimizing metabolic carbon flow and improving the yield of a target product; s2, constructing a dynamic regulation and control system, and regulating key gene expression by stages through an inductive promoter and a feedback regulation and control element to realize dynamic optimization of a metabolic pathway; s3, accurately positioning itaconic acid synthetase in mitochondria or peroxides through signal peptide, reducing generation of byproducts, enhancing DGA1 gene expression by utilizing a CRISPR activation technology, and improving the tolerance of the strain in a low-pH environment; and step S4, adding a xylose isomerase gene, a xylulose reductase gene and a fatty acyl-coenzyme A dehydrogenase gene, optimizing metabolic pathways of xylose and fatty acid, and realizing efficient conversion of multiple carbon sources.