Process for the fermentative production of 3-hydroxypropionic acid and acrylic acid
By enhancing ald expression, weakening gapA expression, and overexpressing pduCDEGH, gdp, and gpp genes in Corynebacterium glutamicum, the problem of efficiently producing 3-hydroxypropionic acid and acrylic acid from inexpensive carbon sources has been solved, achieving a green, safe, and efficient production process.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- BEIJING KANSENBIO TECH CO LTD
- Filing Date
- 2022-09-26
- Publication Date
- 2026-06-26
AI Technical Summary
Existing technologies are insufficient for the efficient and economical production of 3-hydroxypropionic acid and acrylic acid from inexpensive carbon sources, and the chemical production process of acrylic acid is highly polluting and cannot meet industrial demands.
By enhancing the expression of the aldehyde dehydrogenase gene ald in Corynebacterium glutamicum, weakening the expression of the glyceraldehyde-3-phosphate dehydrogenase gene gapA, and overexpressing the diol dehydratase gene pduCDEGH, the 3-phosphate dehydrogenase gene gdp, and the glycerol 3-phosphatase gene gpp, 3-hydroxypropionic acid was produced by fermentation using inexpensive carbon sources such as glucose, and then converted into acrylic acid.
It has achieved efficient production of 3-hydroxypropionic acid and acrylic acid from inexpensive carbon sources. The process is green and safe, with low production costs, and meets industrial needs.
Abstract
Description
Technical Field
[0001] This invention belongs to the fields of genetic engineering and bio-fermentation technology, specifically, it relates to a method for fermenting to produce 3-hydroxypropionic acid and acrylic acid. Background Technology
[0002] 3-Hydroxypropionic acid (3-HP) is an important platform compound and one of the 12 high-value-added bio-based platform chemicals listed by the U.S. Department of Energy. Using 3-HP as a monomer, high-performance biodegradable material poly(3-hydroxypropionic acid) (PHP) can be synthesized. Furthermore, 3-HP can be used to synthesize acrylic acid, 1,3-propanediol, malonic acid, propylenediamine, etc. 3-Hydroxypropionic acid can also be used as an additive and preservative in food and animal feed.
[0003] Acrylic acid is a widely used chemical and a key raw material for the synthesis of polyacrylic acid (salt). Polyacrylic acid has extremely strong water absorption capacity and is widely used in baby diapers, sanitary napkins, and incontinence products. Currently, acrylic acid production mainly relies on chemical methods, typically obtained through the staged oxidation of propylene. This process easily generates a large number of impurities, which can affect the safety of hygiene products and wound care materials. Furthermore, this process depends on fossil resources and requires high temperatures and pressures, producing significant amounts of pollutants and carbon dioxide emissions. Therefore, developing green and safe acrylic acid production technologies that enable the direct production of acrylic acid from inexpensive biomass feedstocks has significant industrial application potential.
[0004] Currently, there are numerous reports on the production of 3-hydroxypropionic acid using biological methods. However, these methods typically involve fermenting glycerol with microorganisms such as Klebsiella pneumoniae to produce 3-hydroxypropionic acid. The soaring price of glycerol in recent years has made this route less economically competitive. Some literature also mentions synthesizing 3-hydroxypropionic acid via malonyl-CoA or β-alanine routes, but these routes yield low concentrations of the final 3-hydroxypropionic acid, which are insufficient to meet the demands of industrial production. Summary of the Invention
[0005] The purpose of this invention is to provide a method for producing 3-hydroxypropionic acid and acrylic acid by fermentation.
[0006] The present invention is conceived as follows: By introducing a synthetic pathway for glycerol and 3-hydroxypropionic acid into *Corynebacterium glutamicum*, the efficient conversion of 3-hydroxypropionic acid from various inexpensive carbon sources such as glucose, sucrose, and molasses can be achieved. Furthermore, the inventors discovered that the aldehyde dehydrogenase encoded by the endogenous *Corynebacterium glutamicum* *ald* gene can efficiently catalyze the oxidation of 3-hydroxypropionaldehyde to produce 3-hydroxypropionic acid. By upregulating the expression of *ald* and downregulating the expression of glyceraldehyde-3-phosphate dehydrogenase *gapA*, high-yield production of 3-hydroxypropionic acid can be achieved. The present invention also provides a method for directly converting fermentation broth containing 3-hydroxypropionic acid to produce acrylic acid.
[0007] To achieve the objectives of this invention, in a first aspect, this invention provides a recombinant Corynebacterium glutamicum, wherein the aldehyde dehydrogenase gene ald is enhanced and the glyceraldehyde-3-phosphate dehydrogenase gene gapA is weakened.
[0008] In this invention, the gene enhancement method can be selected from the following 1) to 4), or any combination thereof:
[0009] 1) By importing a plasmid containing the gene;
[0010] 2) By increasing the copy number of the genes described in the microbial genome;
[0011] 3) By altering the promoter sequence of the genes described in the microbial genome;
[0012] 4) By operatively linking a strong promoter to the gene.
[0013] In this invention, the gene attenuation method can be selected from the following a) to c), or any combination thereof:
[0014] a) By operatively linking a weak promoter to the gene;
[0015] b) Use rare codons;
[0016] c) Use antisense RNA.
[0017] Furthermore, the recombinant Corynebacterium glutamicum also overexpressed the diol dehydratase gene pduCDEGH.
[0018] Furthermore, the recombinant Corynebacterium glutamicum also overexpressed the 3-phosphate dehydrogenase gene gdp and the glycerol 3-phosphatase gene gpp.
[0019] In this invention,
[0020] The gene ald is:
[0021] A1) The nucleotide sequence shown in SEQ ID NO:1;
[0022] A2) A nucleotide sequence of the nucleotide sequence shown in SEQ ID NO:1 that has been substituted, deleted and / or added with one or more nucleotides and expresses a protein with the same function;
[0023] A3) A nucleotide sequence that hybridizes with the sequence shown in SEQ ID NO:1 under stringent conditions and expresses a protein with the same function, wherein the stringent conditions are hybridization at 65°C in 0.1×SSPE containing 0.1% SDS or 0.1×SSC containing 0.1% SDS, followed by washing the membrane with the same solution; or
[0024] A4) is a nucleotide sequence that has more than 90% homology with the nucleotide sequences of A1), A2) or A3) and expresses the same functional protein.
[0025] The gene gapA is:
[0026] B1) The nucleotide sequence shown in SEQ ID NO:2;
[0027] B2) A nucleotide sequence of the nucleotide sequence shown in SEQ ID NO:2 that has been substituted, deleted and / or added with one or more nucleotides and expresses a protein with the same function;
[0028] B3) A nucleotide sequence that hybridizes with the sequence shown in SEQ ID NO:2 under stringent conditions and expresses a protein with the same function, wherein the stringent conditions are hybridization at 65°C in 0.1×SSPE containing 0.1% SDS or 0.1×SSC containing 0.1% SDS, followed by washing the membrane with the same solution; or
[0029] B4) is a nucleotide sequence that has more than 90% homology with the nucleotide sequences of B1), B2) or B3) and expresses the same functional protein.
[0030] The gene pduCDEGH is:
[0031] C1) The nucleotide sequence shown in SEQ ID NO:3;
[0032] C2) A nucleotide sequence of the nucleotide sequence shown in SEQ ID NO:3 that has been substituted, deleted and / or added with one or more nucleotides and expresses a protein with the same function;
[0033] C3) A nucleotide sequence that hybridizes with the sequence shown in SEQ ID NO:3 under stringent conditions and expresses a protein with the same function, wherein the stringent conditions are hybridization at 65°C in 0.1×SSPE containing 0.1% SDS or 0.1×SSC containing 0.1% SDS, followed by washing the membrane with the same solution; or
[0034] Nucleotide sequences of C4 that have more than 90% homology with the nucleotide sequences of C1), C2) or C3) and express the same functional protein.
[0035] The gene gdp is:
[0036] D1) The nucleotide sequence shown in SEQ ID NO:4;
[0037] D2) A nucleotide sequence of the nucleotide sequence shown in SEQ ID NO:4 that has been substituted, deleted and / or added with one or more nucleotides and expresses a protein with the same function;
[0038] D3) A nucleotide sequence that hybridizes with the sequence shown in SEQ ID NO:4 under stringent conditions and expresses the same functional protein, wherein the stringent conditions are hybridization at 65°C in 0.1×SSPE containing 0.1% SDS or 0.1×SSC containing 0.1% SDS, followed by washing the membrane with the same solution; or
[0039] A nucleotide sequence that has more than 90% homology with the nucleotide sequences of D1), D2) or D3) and expresses the same functional protein.
[0040] The gene gpp is:
[0041] E1) The nucleotide sequence shown in SEQ ID NO:5;
[0042] E2) A nucleotide sequence of the nucleotide sequence shown in SEQ ID NO:5 that has been substituted, deleted and / or added with one or more nucleotides and expresses a protein with the same function;
[0043] E3) A nucleotide sequence that hybridizes with the sequence shown in SEQ ID NO:5 under stringent conditions and expresses a protein with the same function, wherein the stringent conditions are hybridization at 65°C in 0.1×SSPE containing 0.1% SDS or 0.1×SSC containing 0.1% SDS, followed by washing the membrane with the same solution; or
[0044] Nucleotide sequences of E4 that share more than 90% homology with the nucleotide sequences of E1), E2) or E3) and express the same functional protein.
[0045] In one specific embodiment of the present invention, the recombinant Corynebacterium glutamicum is constructed by overexpressing genes ald, pduCDEGH, gdp and gpp in Corynebacterium glutamicum and replacing the start codon of gene gapA with GTG.
[0046] Secondly, the present invention provides a method for constructing the recombinant Corynebacterium glutamicum, wherein the above-mentioned genes can be modified or altered using conventional genetic engineering methods.
[0047] Thirdly, the present invention provides the application of the recombinant Corynebacterium glutamicum in the fermentation production of 3-hydroxypropionic acid.
[0048] Furthermore, 3-hydroxypropionic acid is produced by fermentation using the recombinant Corynebacterium glutamicum as a raw material and an inexpensive carbon source.
[0049] The inexpensive carbon source can be selected from at least one of molasses, sucrose, glucose, cellobiose, etc.
[0050] Fourthly, the present invention provides a method for producing acrylic acid, wherein the recombinant Corynebacterium glutamicum is fermented and cultured, and the 3-hydroxypropionic acid produced by fermentation is acidified and dehydrated by heating to obtain acrylic acid.
[0051] Further, the method includes: adding concentrated phosphoric acid solution to the fermentation broth containing 3-hydroxypropionic acid, adjusting the pH value to 1-2, and heating the fermentation broth to 100-140℃ for 1-5 hours (preferably 140℃ for 2 hours).
[0052] By employing the above technical solution, the present invention has at least the following advantages and beneficial effects:
[0053] This invention provides a recombinant Corynebacterium glutamicum, in which the expression of its own aldehyde dehydrogenase gene *ald* is upregulated, the expression of glyceraldehyde-3-phosphate dehydrogenase *gapA* is downregulated, and the heterologous diol dehydratase gene *pduCDEGH*, heterologous 3-phosphate dehydrogenase *gdp*, and glycerol-3-phosphate phosphatase *gpp* are expressed. This recombinant microorganism is fermented in shake flasks or fermenters using glucose or other organic carbon sources as substrates to obtain 3-hydroxypropionic acid. The 3-hydroxypropionic acid in the fermentation broth is acidified and dehydrated by heating to further obtain acrylic acid. This recombinant microorganism can efficiently produce 3-hydroxypropionic acid and acrylic acid using inexpensive glucose, sucrose, molasses, etc., as raw materials. The production process is green, safe, and simple, and has good market application prospects. Detailed Implementation
[0054] The following examples are used to illustrate the present invention, but are not intended to limit the scope of the invention. Unless otherwise specified, the examples are conducted under conventional experimental conditions, such as those described in Sambrook et al., Molecular Cloning: a Laboratory Manual (Sambrook J & Russell DW, 2001), or as recommended by the manufacturer's instructions.
[0055] Example 1: Construction of a 3-hydroxypropionaldehyde synthesis module
[0056] The 3-phosphate dehydrogenase gene gdp (gene sequence shown in SEQ ID NO:4) and the glycerol 3-phosphatase gene gpp (gene sequence shown in SEQ ID NO:5) were artificially synthesized. Using the gpd gene fragment as a template, PCR was performed using gpd-F (5′-attaagcttgcatgcctgcactttaagaaggagatataccaatggctgctgctgctgatag-3′) and gpd-R (5′-ggtatatctccttcttaaagtaatcttcatgtagatctaa-3′) as primers to obtain a gpd-1 fragment of approximately 1.26 kb, which was then purified by PCR. Using the gpp gene fragment as a template, PCR was performed using gpp-F (5′-attaagcttgcatgcctgcactttaagaaggagatataccaatgggattgactactaaacc-3′) and gpp-R (5′-ggtatatctccttcttaaagttaccatttcaacagatcgt-3′) as primers to obtain a gpp-1 fragment of approximately 0.8 kb, which was then purified by PCR. The pXMJ19 plasmid (purchased from Addgene) was double-digested with PstI and XbaI. The purified gpd-1 and gpp-1 fragments were ligated into pXMJ19 in one step using the Gibson Assembly kit (NEB), and the resulting recombinant plasmid was named pXMJ-gpd-gpp.
[0057] Using the genome of Klebsiella pneumoniae as a template, PCR was performed using pdu-F (5′-ggatccccgggtaccgagctctttaagaaggagatataccatgagatcgaaaagatttga-3′) and pdu-R (5′-caaaacagccaagctgaattttaagcatggcgatcccgaa-3′) as primers to obtain a pduCDEGH operon fragment of approximately 5.1 kb containing diol dehydratase and its activator (sequence shown in SEQ ID NO:2). The PCR product was then purified. The pXMJ-gpd-gpp plasmid was double-digested with KpnI and EcoRI. The purified pduCDEGH fragment was ligated into pXMJ-gpd-gpp in one step using a Gibson Assembly kit (NEB). The resulting recombinant plasmid was named pXMJ-gpd-gpp-pduCDEGH.
[0058] The plasmid pXMJ-gpd-gpp-pduCDEGH was transformed into Corynebacterium glutamicum ATCC 13032 by electroporation. The recombinant bacteria were obtained by screening on LB agar plates containing 10 mg / L chloramphenicol and named Cg / pXMJ-gpd-gpp-pduCDEGH.
[0059] Example 2: Construction of a recombinant strain with enhanced expression of the aldehyde dehydrogenase gene ald
[0060] The aldehyde dehydrogenase gene ald exists in Corynebacterium glutamicum, and enhancing the expression of ald can significantly increase the production of 3-hydroxypropionic acid.
[0061] Using the genome of Corynebacterium glutamicum ATCC13032 as a template, PCR was performed using ald-F (5′-acagctatgacatgattacgtataagaaggagatatacaatgactgtctacgcaaatcc-3′) and ald-R (5′-tagaggatccccgggtaccgagtcttgtcaggccaaccca-3′) primers to obtain an approximately 1.2 kb ald gene fragment, and the PCR product was purified. The plasmid pEC-K18mob2 (purchased from Addgene) was double-digested with EcoRI and SacI. The purified ald fragment was ligated into pEC-K18mob2 using a Gibson Assembly kit (NEB), and the resulting recombinant plasmid was named pEC-ald. pEC-ald was transferred into Corynebacterium glutamicum Cg / pXMJ-gpd-gpp-pduCDEGH by electroporation. Recombinant bacteria were obtained by screening on LB agar plates containing 50 mg / L kanamycin and named Cg / pXMJ-gpd-gpp-pduCDEGH / pEC-ald.
[0062] The bacterial strain Cg / pXMJ-gpd-gpp-pduCDEGH / pEC-ald and the control strain Cg / pXMJ-gpd-gpp-pduCDEGH were inoculated into fermentation medium and cultured at 30℃ and 200 rpm. When the cell OD... 600 When the concentration reaches 2-3, add 0.1 mM IPTG for induction and continue fermentation for 48 h.
[0063] Fermentation medium formula (g / L): glucose 100, (NH4)2SO4 10, K2HPO4 0.5, MgSO4 0.5, FeSO4 0.01, MnSO4 0.01, thiamine 0.005, β-alanine 0.01, nicotinic acid 0.005, corn steep liquor 10, biotin 0.001, thiamine hydrochloride 0.001, chloramphenicol 0.005, and kanamycin 0.05.
[0064] After 48 hours of fermentation, the product of the strain was detected by high-performance liquid chromatography (HPLC). The strain Cg / pXMJ-gpd-gpp-pduCDEGH / pEC-ald produced 35.2 g / L of 3-hydroxypropionic acid, while the control strain Cg / pXMJ-gpd-gpp-pduCDEGH produced only 10.1 g / L of 3-hydroxypropionic acid. This indicates that upregulating the expression of ald can significantly increase the yield of 3-hydroxypropionic acid.
[0065] Similarly, upregulating the expression of the ald gene in the Corynebacterium glutamicum genome can significantly increase the yield of 3-hydroxypropionic acid. The recombinant strain Cg-ald was constructed by replacing the promoter of the ald gene in Corynebacterium glutamicum ATCC13032 with the strong promoter tac (5′-ttgacaattaatcatcggctcgtataatg-3′). The recombinant strain obtained by electroporating the plasmid pXMJ-gpd-gpp-pduCDEGH into strain Cg-ald was named Cg-ald / pXMJ-gpd-gpp-pduCDEGH. Under the same fermentation conditions, the 3-hydroxypropionic acid yield of strain Cg-ald / pXMJ-gpd-gpp-pduCDEGH reached 30.4 g / L, significantly higher than that of the control strain (10.1 g / L).
[0066] The construction process of strain Cg-ald is as follows: using the genome of Corynebacterium glutamicum ATCC13032 as a template, PCR was performed using ald-up-F1 (5′-tcatcagcgatggactcatgaacaa-3′) and ald-up-R1 (5′-ttgacaattaatcatcggctcgtataatgcttttgaaaggctttcggcg-3′) as primers to obtain the ald-up1 gene fragment approximately 1.0 kb upstream of ald, and the PCR product was purified. Using the genome of *Corynebacterium glutamicum* ATCC13032 as a template, PCR was performed using ald-down-F1 (5′-cattatacgagccgatgattaattgtcaattattacccctgttcgggtg-3′) and ald-down-R1 (5′-atcaccgtgcgtatcccaac-3′) primers to obtain the *ald-down1* gene fragment, approximately 1.0 kb downstream of gapA, and the PCR product was purified. The plasmid pK18mobsacB (purchased from Addgene) was double-digested with EcoRI and XbaI. The purified *ald-down1* and *ald-up1* fragments were ligated into pEC-K18mob2 using a Gibson Assembly kit (NEB), resulting in a recombinant plasmid named pK18-ald. pK18-ald was electroporated into *Corynebacterium glutamicum* ATCC 13032, and the correct recombinant strain was obtained through secondary screening and sequencing, named Cg-ald.
[0067] Example 3: Downregulating gapA gene expression to increase 3-hydroxypropionic acid production
[0068] Based on the above strains, it was further discovered that downregulating the expression of the gapA gene of glyceraldehyde-3-phosphate dehydrogenase can significantly increase the yield of 3-hydroxypropionic acid.
[0069] The expression of gapA was weakened by replacing ATG with the rare start codon GTG. Using the genome of Corynebacterium glutamicum ATCC13032 as a template, PCR was performed using gapA-up-F1 (5′-acagctatgacatgattacgcgatgtcggtggaaaccagt-3′) and gapA-up-R1 (5′-gagacacaacgtgaccattcgtgttggtattaacgg-3′) as primers to obtain the approximately 1.0 kb upstream gene gapA-up1 fragment, and the PCR product was purified. Using the genome of Corynebacterium glutamicum ATCC13032 as a template, PCR was performed using gapA-down-F1 (5′-gaatggtcacgttgtgtctcctctaaagattgtaggaaatg-3′) and gapA-down-R1 (5′-tgcatgcctgcaggtcgacttcgcggcgaaaacgaaagat-3′) as primers to obtain the gapA-down1 gene fragment, approximately 1.0 kb downstream of gapA, and the PCR product was purified. The plasmid pK18mobsacB (purchased from Addgene) was double-digested with EcoRI and XbaI. The purified gapA-down1 and gapA-up1 fragments were ligated into pEC-K18mob2 using a Gibson Assembly kit (NEB), and the resulting recombinant plasmid was named pK18-gapA1. pK18-gapA1 was electroporated into Corynebacterium glutamicum ATCC 13032. After secondary selection and sequencing, a recombinant strain with the gapA start codon ATG correctly replaced by GTG was obtained and named Cg-GTG. Plasmids pEC-ald and pXMJ-gpd-gpp-pduCDEGH were then electroporated into Corynebacterium glutamicum Cg-GTG, resulting in a recombinant strain named Cg-GTG / pXMJ-gpd-gpp-pduCDEGH / pEC-ald.
[0070] The strain Cg-GTG / pXMJ-gpd-gpp-pduCDEGH / pEC-ald and the control strain Cg / pXMJ-gpd-gpp-pduCDEGH / pEC-ald were inoculated into the fermentation medium and cultured under the same conditions as in Example 2.
[0071] After 48 hours of fermentation, the product of the strain was detected by high-performance liquid chromatography (HPLC). The strain Cg-GTG / pXMJ-gpd-gpp-pduCDEGH / pEC-ald produced 47.2 g / L of 3-hydroxypropionic acid, while the control strain Cg / pXMJ-gpd-gpp-pduCDEGH / pEC-ald produced only 35.2 g / L of 3-hydroxypropionic acid. This indicates that downregulating gapA expression can significantly increase the yield of 3-hydroxypropionic acid.
[0072] Similarly, strains Cg-GTG / pXMJ-gpd-gpp-pduCDEGH / pEC-ald, Cg / pXMJ-gpd-gpp-pduCDEGH / pEC-ald, and the control strain Cg / pXMJ-gpd-gpp-pduCDEGH were inoculated into sucrose fermentation medium and cultured. Except for replacing 100 g / L glucose with 100 g / L sucrose, all other conditions in the medium remained unchanged, and the culture conditions were exactly the same as in Example 2. The strain Cg-GTG / pXMJ-gpd-gpp-pduCDEGH / pEC-ald can produce 45.4 g / L of 3-hydroxypropionic acid, the strain Cg / pXMJ-gpd-gpp-pduCDEGH / pEC-ald produces 33.1 g / L of 3-hydroxypropionic acid, while the control strain Cg / pXMJ-gpd-gpp-pduCDEGH only produces 7.3 g / L of 3-hydroxypropionic acid.
[0073] Example 4: 3-hydroxypropionic acid in fermentation broth was converted into acrylic acid.
[0074] Concentrated phosphoric acid solution was added to the fermentation broth containing 3-hydroxypropionic acid in Example 3 to adjust the pH of the solution to 1-2. The solution was heated to 140°C and reacted for 2 hours. The concentration of the product in the fermentation broth was then measured. The results showed that more than 90% of the 3-hydroxypropionic acid was converted into acrylic acid.
[0075] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.
Claims
1. Recombinant Corynebacterium glutamicum, characterized in that, The aldehyde dehydrogenase gene ald in the recombinant Corynebacterium glutamicum was enhanced, and the glyceraldehyde-3-phosphate dehydrogenase gene gapA was weakened; the recombinant Corynebacterium glutamicum also overexpressed the diol dehydratase gene pduCDEGH, the 3-phosphate dehydrogenase gene gdp, and the glycerol 3-phosphate phosphatase gene gpp. The nucleotide sequence of gene ald is shown in SEQ ID NO:1, the nucleotide sequence of gene gapA is shown in SEQ ID NO:2, the nucleotide sequence of gene pduCDEGH is shown in SEQ ID NO:3, the nucleotide sequence of gene gdp is shown in SEQ ID NO:4, and the nucleotide sequence of gene gpp is shown in SEQ ID NO:
5.
2. The recombinant Corynebacterium glutamicum according to claim 1, characterized in that, Gene enhancement methods are selected from the following 1) to 4), or any combination thereof: 1) By importing a plasmid containing the gene; 2) By increasing the copy number of the genes mentioned in the microbial genome; 3) By altering the promoter sequence of the genes described in the microbial genome; 4) By operatively linking a strong promoter to the gene.
3. The recombinant Corynebacterium glutamicum according to claim 1 or 2, characterized in that, The recombinant Corynebacterium glutamicum was constructed by overexpressing the genes ald, pduCDEGH, gdp, and gpp in Corynebacterium glutamicum and replacing the start codon of the gene gapA with GTG.
4. The use of the recombinant Corynebacterium glutamicum according to any one of claims 1-3 in the fermentation production of 3-hydroxypropionic acid.
5. The application according to claim 4, characterized in that, 3-hydroxypropionic acid is produced by fermentation using inexpensive carbon sources as raw materials; The inexpensive carbon source is selected from at least one of molasses, sucrose, glucose, and cellobiose.
6. A method for producing acrylic acid, characterized in that, The recombinant Corynebacterium glutamicum according to any one of claims 1-3 is fermented and cultured, and the 3-hydroxypropionic acid produced by fermentation is acidified and dehydrated by heating to obtain acrylic acid.
7. The method according to claim 6, characterized in that, The method includes: adding concentrated phosphoric acid solution to a fermentation broth containing 3-hydroxypropionic acid, adjusting the pH value to 1-2, and heating the fermentation broth to 100-140℃ for 1-5 hours.