Escherichia coli engineering bacterium for producing 1, 3-dihydroxyacetone by using glucose

Abstract

The invention discloses an escherichia coli engineering bacterium for producing 1, 3-dihydroxyacetone by using glucose. The escherichia coli engineering bacterium for producing the 1, 3-dihydroxyacetone by using the glucose as the carbon source, provided by the invention, is particularly escherichia coli TZ-249, and the preservation number of the escherichia coli engineering bacterium in the China General Microbiological Culture Collection Center is CGMCC (China General Microbiological Culture Collection Center) No.26177. The method disclosed by the invention has important significance for producing a bulk chemical 1, 3-dihydroxyacetone by using glucose as a raw material.

Description

Technical Field

[0001] The invention relates to the field of biotechnology, and in particular to an engineered Escherichia coli strain that utilizes glucose to produce 1,3-dihydroxyacetone. Background Art

[0002] 1,3-Dihydroxyacetone (DHA) is the simplest three-carbon ketose with three active groups. It can participate in a variety of reactions and is widely used in the chemical, pharmaceutical, feed, cosmetic and food industries. The main methods for synthesizing DHA are chemical synthesis and microbial synthesis. Due to the disadvantages of chemical synthesis such as low conversion efficiency, selective oxidation efficiency, and high catalyst cost, researchers prefer to use environmental optimization and microbial methods with higher conversion efficiency to synthesize DHA. At present, the industrial production of DHA mainly uses Gluconobacter oxydans to convert glycerol substrates, but there are also problems such as high concentrations of glycerol substrates and DHA products inhibiting bacterial growth, by-products, and complex fermentation processes. In recent years, with the technological advances in the field of synthetic biology, the construction of efficient microbial cell factories to synthesize DHA using glucose as a substrate has gradually become a research trend. Summary of the invention

[0003] The purpose of the present invention is to provide an engineered Escherichia coli strain that utilizes glucose to produce 1,3-dihydroxyacetone.

[0004] In a first aspect, the present invention provides Escherichia coli TZ-249, whose deposit number is CGMCC No.26177.

[0005] In a second aspect, the present invention provides a bacterial agent, the active ingredient of which is the Escherichia coli TZ-249 or its bacterial liquid or culture liquid or fermentation liquid described in the first aspect.

[0006] The bacterial agent may contain, in addition to the active ingredients, auxiliary materials or carriers commonly used in the art.

[0007] In a third aspect, the present invention provides a use of the TZ-249 or its bacterial solution or its culture solution or its fermentation solution described in the first aspect or the bacterial agent described in the second aspect in at least one of the following:

[0008] 1) Production of 1,3-dihydroxyacetone;

[0009] 2) Increase the yield of 1,3-dihydroxyacetone;

[0010] 3) Increase the production rate of 1,3-dihydroxyacetone;

[0011] 4) Promote the conversion of glucose into 1,3-dihydroxyacetone.

[0012] In the above application, the production of 1,3-dihydroxyacetone is to use glucose as a carbon source to produce 1,3-dihydroxyacetone.

[0013] In a fourth aspect, the present invention provides a method for producing 1,3-dihydroxyacetone, comprising the following steps: fermenting and culturing the Escherichia coli TZ-249 described in the first aspect to obtain 1,3-dihydroxyacetone.

[0014] In the above method, the fermentation culture uses glucose as a carbon source to produce 1,3-dihydroxyacetone.

[0015] Furthermore, the fermentation medium used in the fermentation culture may be a semi-synthetic medium CM9 containing 50 g / L glucose.

[0016] In a specific embodiment of the present invention, the formula of the fermentation medium is as follows: 1L contains 50g glucose, 5g corn syrup powder, NH 4 Cl 1g, (NH 4 ) 2 SO 4 0.87 g, MgSO 4 7H 2 O 0.5 g, KCl 0.47 g, KH 2 PO 4 0.14g, and trace elements ZnCl 2 1.47μΜ, H 3 BO 3 0.81 μΜ, CoCl 2 6H 2 O 0.84 μΜ, CuCl 2 ·2H 2 O 0.59 μΜ, FeCl 3 6H 2 O 5.92 μΜ, Na 2 MoO 4 ·2H 2 O 0.83μΜ, the balance is water. When the fermentation culture is carried out, 700g / L glucose is used as feed, and ammonia water is used as a neutralizer. The fermentation conditions are temperature 37°C, pH 7.0, dissolved oxygen 30%, ventilation flow upper limit 10L / min, lower limit 3L / min, stirring speed upper limit 1000r / min, lower limit 300r / min, and after inoculation, the dissolved oxygen content is controlled by controlling the dissolved oxygen, stirring speed, and ventilation cascade.

[0017] The starting strain in the present invention is an Escherichia coli engineered bacterium TZ-237 that uses glucose as a carbon source to produce 1,3-dihydroxyacetone. However, since 1,3-dihydroxyacetone and phosphate undergo a non-enzymatic chemical reaction inside and outside the cell to generate methylglyoxal, the physiological metabolism of the cell is inhibited and interfered, resulting in the growth, glucose metabolism and DHA production of the 1,3-dihydroxyacetone-producing engineered strain being affected. In order to improve strain growth and increase the yield of 1,3-dihydroxyacetone, it is necessary to carry out in-depth tolerance modification and strain screening of the 1,3-dihydroxyacetone-producing engineered bacteria to obtain the strain recombinant Escherichia coli TZ-249 of the present invention.

[0018] The experiment of the present invention proves that the recombinant Escherichia coli TZ-237 is fermented for 5L and 30h, and the 1,3-dihydroxyacetone output reaches 30.1g / L, the production rate reaches 1g / L / h, and the conversion rate of glucose to 1,3-dihydroxyacetone is 0.95mol / mol. The recombinant Escherichia coli TZ-249 is fermented for 5L and 30h, and the 1,3-dihydroxyacetone output reaches 83.7g / L, the production rate reaches 2.79g / L / h, and the conversion rate of glucose to 1,3-dihydroxyacetone is 0.96mol / mol. It can be seen that the recombinant Escherichia coli TZ-249 obtained by evolutionary metabolism from recombinant Escherichia coli TZ-237 has a greatly improved ability to produce 1,3-dihydroxyacetone, and the production rate is also greatly improved. The present invention is of great significance for producing 1,3-dihydroxyacetone using glucose as a substrate.

[0019] Collection Instructions

[0020] Strain name: Escherichia coli

[0021] Latin name: Escherichia coli

[0022] Reference biomaterial strain: TZ-249

[0023] Depository: China National Microbiological Culture Collection Administration General Microbiology Center

[0024] Abbreviation of depository institution: CGMCC

[0025] Address: No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing

[0026] Date of deposit: December 8, 2022

[0027] CGMCC Registration Number: CGMCC No.26177 BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1To obtain recombinant Escherichia coli TZ-249 through evolutionary metabolism, metabolic evolution was carried out in a culture medium containing 20-50 g / L 1,3-dihydroxyacetone to improve the strain's tolerance to 1,3-dihydroxyacetone.

[0029] Figure 2 The recombinant E. coli TZ-237 was fermented in a 5L fermenter. ▲ represents the glucose concentration in the fermentation broth; ● represents the OD600nm value of the bacterial broth; ■ represents the 1,3-dihydroxyacetone concentration in the fermentation broth. The unit g / L represents the content of the target substance per liter of fermentation broth.

[0030] Figure 3 The recombinant E. coli TZ-249 was fermented in a 5L fermenter. ▲ represents the glucose concentration in the fermentation broth; ● represents the OD600nm value of the bacterial broth; ■ represents the 1,3-dihydroxyacetone concentration in the fermentation broth. The unit g / L represents the content of the target substance per liter of fermentation broth. DETAILED DESCRIPTION

[0031] Unless otherwise specified, the experimental methods used in the following examples are conventional methods.

[0032] Unless otherwise specified, the materials and reagents used in the following examples can be obtained from commercial sources.

[0033] The Gene IDs of the genes involved in the following embodiments are all Gene IDs in the NCBI database (all gene ID information is from the NCBI database, web link: https: / / www.ncbi.nlm.nih.gov / nuccore / CP000946.1 / ), specifically as follows: The nucleotide sequence of the gene encoding the endogenous glucose-specific PTS enzyme IIBC component PtsG (i.e., the ptsG gene) is Gene ID: EcolC_2500 (submission date is 2008.2.14). The nucleotide sequence of the gene encoding the endogenous pyruvate formate lyase PflB (i.e., the pflB gene) is Gene ID: EcolC_2693 (submission date is 2008.2.14). The nucleotide sequence of the gene encoding the pyruvate oxidase PoxB (i.e., the poxB gene) is Gene ID: EcolC_2725 (submission date is 2008.2.14). The nucleotide sequence of the gene encoding endogenous alcohol dehydrogenase AdhE (ie, adhE gene) is Gene ID: EcolC_2387 (submission date: 2008.2.14).

[0034] The nucleotide sequence of the gene encoding the endogenous histidine phosphate carrier protein PtsH (i.e., the ptsH gene) is GeneID: EcolC_1263 (submitted on February 14, 2008). The nucleotide sequence of the gene encoding the endogenous phosphoenolpyruvate-protein phosphotransferase IPtsI (i.e., the ptsI gene) is Gene ID: EcolC_1262 (submitted on February 14, 2008). The nucleotide sequence of the gene encoding the endogenous glucose-specific enzyme II complex EIIA Crr (i.e., the crr gene) is GeneID: EcolC_1261 (submitted on February 14, 2008). The nucleotide sequence of the gene encoding the endogenous dihydroxyacetone kinase DhaRKLM (i.e., the dhaRKLM gene) is Gene ID: EcolC_2425 (submission date: 2008.2.14), EcolC_2426 (submission date: 2008.2.14), EcolC_2427 (submission date: 2008.2.14), and EcolC_2428 (submission date: 2008.2.14). The nucleotide sequence of the gene encoding the endogenous glycerol kinase GlpK (i.e., the glpK gene) is Gene ID: EcolC_4092 (submission date: 2008.2.14). The nucleotide sequence of the gene encoding the methylglyoxal synthase MgsA (i.e., the mgsA gene) is Gene ID: EcolC_2633 (submission date: 2008.2.14). The nucleotide sequence of the gene encoding glycerol dehydrogenase GldA (i.e., gldA gene) is Gene ID: EcolC_4070 (submission date: 2008.2.14). The nucleotide sequence of the gene encoding L-arabinose isomerase AraA (i.e., araA gene) is Gene ID: EcolC_3595 (submission date: 2008.2.14). The nucleotide sequence of the gene encoding ribulose kinase AraB (i.e., araB gene) is Gene ID: EcolC_3594 (submission date: 2008.2.14). The nucleotide sequence of the gene encoding endogenous triosephosphate isomerase TpiA (i.e., tpiA gene) is Gene ID: EcolC_4099 (submission date: 2008.2.14).

[0035] The nucleotide sequence of the gene encoding endogenous 6-phosphofructoyl aldolase 1FsaA (i.e., fsaA gene) is Gene ID: EcolC_2819 (submission date: 2008.2.14). The nucleotide sequence of the gene encoding endogenous 6-phosphofructoyl aldolase 2FsaB (i.e., fsaB gene) is Gene ID: EcolC_4069 (submission date: 2008.2.14). The nucleotide sequence of the gene encoding endogenous glycerol transporter GlpF (i.e., glpF gene) is Gene ID: EcolC_4091 (submission date: 2008.2.14). The nucleotide sequence of the gene encoding endogenous 6-phosphofructoyl aldolase Zwf (i.e., zwf gene) is Gene ID: EcolC_1780 (submission date: 2008.2.14). The nucleotide sequence of the gene encoding the endogenous phosphogluconate dehydratase Edd (i.e., the edd gene) is Gene ID: EcolC_1781 (submission date: 2008.2.14). The nucleotide sequence of the gene encoding the endogenous 2-keto-3-deoxy-6-phosphogluconate aldehyde Eda (i.e., the eda gene) is Gene ID: EcolC_1782 (submission date: 2008.2.14). The above Gene IDs are all Gene IDs in the NCBI database.

[0036] The Escherichia coli strain TZ-237 involved in the following embodiments is a strain of ATCC 8739 Escherichia coli in which the full-length ptsHI-crr gene (ptsHI-crr gene positions 1-2622, ptsHI-crr gene consists of three genes ptsH, ptsI and crr, and the sequence numbers of the three genes are Gene ID: EcoLC_1261, EcoLC_1262, EcoLC_1263), the full-length dhaRKLM gene (dhaRKLM gene positions 1-5290, dhaRKLM gene consists of four genes dhaR, dhaK, dhaL and dhaM, and the sequence numbers of the four genes are Gene ID: EcoLC_2425, EcoLC_2426, EcoLC_2427, EcoLC_2428), the glpK gene (Gene ID: EcoLC_4092) positions 1-1509, the mgsA gene (Gene ID: EcoLC_4093) positions 1-1510, the The 1st to 459th positions of the gldA gene (Gene ID: EcolC_2633), the 46th to 1104th positions of the gldA gene (Gene ID: EcolC_2633), the 274th to 3159th positions of the araBA gene (araBA gene is composed of araB gene and araA gene, and the knockout part is from the 274th position of the araB gene to the end of the araA gene; the two genes are Gene ID: EcolC_3594, EcolC_3595) and the 1st to 758th positions of the tpiA gene (Gene ID: EcolC_4099) were knocked out to inactivate the functions of these genes, and P 93 -T7RNAP fragment (SEQ ID No. 1, position 78-2682) replaced the fragment shown in position 151-1434 of ptsG gene in ATCC 8739 genome, and poxB::P T7 -hdpA fragment (SEQ ID No. 2, position 56-1158) replaced the fragment shown in position 396-1083 of the poxB gene in the ATCC 8739 genome, and pflB::P T7 -hdpA fragment (SEQ ID No. 4, 56-1158) replaced the fragment shown in the 1-2283 position of the pflB gene in the ATCC 8739 genome, and the 1-663 position of the fsaA gene and the 1-663 position of the fsaB gene were knocked out, and the 1-813 position of the glpF gene were knocked out, so that P 46 -nox (SEQ ID No. 3, positions 86-1621) replaces the 102-2676 fragment of the adhE gene of Escherichia coli; knocks out positions 1-1476 of the zwf gene, positions 1-1812 of the edd gene, and positions 1-642 of the eda gene to obtain recombinant bacteria.

[0037] The genotype of Escherichia coli strain TZ-237 is shown in Table 1.

[0038] Table 1 shows the strains used in the present invention.

[0039]

[0040] Example 1: Obtaining recombinant Escherichia coli TZ-249 by evolutionary metabolism

[0041] Starting from the recombinant Escherichia coli TZ-237, the tolerance to 1,3-dihydroxyacetone was improved through evolutionary metabolism, thereby improving the strain's ability to produce 1,3-dihydroxyacetone.

[0042] Seed culture medium (1 L): 5 g yeast extract, 10 g tryptone, 10 g NaCl, and the balance is water.

[0043] CM9 fermentation medium (1L): glucose 50g, corn syrup powder 5g, NH 4 Cl 1g, (NH 4 ) 2 SO 4 0.87 g, MgSO 4 7H 2 O 0.5 g, KCl 0.47 g, KH 2 PO 4 0.14g, and trace elements ZnCl 2 1.47μΜ, H 3 BO 3 0.81 μΜ, CoCl 2 6H 2 O 0.84 μΜ, CuCl 2 ·2H 2 O 0.59 μΜ, FeCl 3 6H 2 O 5.92 μΜ, Na 2 MoO 4 ·2H 2 O 0.83μΜ, the balance is water.

[0044] Acclimation medium: 20-50 g / L (concentration in acclimation medium) of 1,3-dihydroxyacetone (DHA) was added to the CM9 fermentation medium to obtain an acclimation medium with a DHA concentration ranging from 20 g / L to 50 g / L.

[0045] Acclimation culture: The recombinant E. coli TZ-237 monoclone on the LB plate was transferred to 2 ml seed culture medium, and cultured at 37°C and 250 rpm for 18 hours to obtain seed culture solution. The seed culture solution was then transferred to 50 ml acclimation medium containing 20 g / L and gradually increased to 50 g / L 1,3-dihydroxyacetone at an inoculation rate of 1% (volume ratio). During the acclimation process, 1,3-dihydroxyacetone was increased successively from 20 g / L, 25 g / L, 30 g / L, 33 g / L, 36 g / L, 38 g / L, 40 g / L, 42 g / L, 44 g / L, 45 g / L, 46 g / L, 47 g / L, 48 g / L, 49 g / L to 50 g / L.

[0046] After 81 generations of transfer culture ( Figure 1 ), and finally obtained strain TZ-249 that grew well in the acclimation medium containing 50 g / L 1,3-dihydroxyacetone.

[0047] Strain TZ-249 was deposited in the China General Microbiological Culture Collection Center (CGMCC, address: No. 3, Yard No. 1, Beichen West Road, Chaoyang District, Beijing) on ​​December 8, 2022. Its deposit number is CGMCC No. 26177, and the recommended classification name is Escherichia coli.

[0048] Example 2: Shake flask fermentation of recombinant Escherichia coli TZ-237 and TZ-249

[0049] The recombinant Escherichia coli TZ-237 and TZ-249 were evaluated for fermentation production of 1,3-dihydroxyacetone.

[0050] Seed culture medium: same as in Example 1.

[0051] CM9 fermentation medium: same as in Example 1.

[0052] Shake flask fermentation culture: The recombinant E. coli TZ-237 and TZ-249 monoclones on the LB plate were transferred to 2 ml seed culture medium, and cultured at 37°C and 250 rpm for 18 hours to obtain seed culture solution. The seed culture solution was then transferred to 50 ml CM9 fermentation medium at a 1% (volume ratio) inoculation amount, and cultured at 37°C and 250 r / min for 24 hours, and the fermentation product was collected; centrifuged at 10000g for 2 minutes, and the supernatant was collected.

[0053] The supernatant was analyzed by HPLC for 1,3-dihydroxyacetone production. 1,3-dihydroxyacetone standard was purchased from Shanghai Myrel Biochemical Technology Co., Ltd., with the product catalog number B66080-500G. The peak time of 1,3-dihydroxyacetone was 9.5 min. The standard curve equation for HPLC quantitative detection of 1,3-dihydroxyacetone was: y=346656x+12665, R 2 =0 9999. The supernatant was diluted a certain times and then quantitatively tested by HPLC. The peak area obtained by the test was the y value, which was substituted into the standard curve equation of 1,3-dihydroxyacetone to obtain the x value, which was multiplied by the dilution multiple to obtain the yield.

[0054] The calculation method of mass conversion rate is: The calculation method of molar conversion rate is: Conversion rate (mol / mol) = (dihydroxyacetone production / 90) / ((total amount of glucose-residual sugar) / 180)*100%

[0055] HPLC detection conditions: using Yuexu The fermentation products were analyzed by HPLC using Sugar-Ca chromatographic column. The column temperature was controlled at 70°C, the mobile phase was 0.5g / L EDTA-Ca aqueous solution, the flow rate was 0.4ml / min, the injection volume of each sample was 20μl, and the detection time was 30 minutes.

[0056] The shake flask fermentation test results are shown in Table 2 below. The 1,3-dihydroxyacetone production of TZ-237 and TZ-249 were 12.99 g / L and 13.48 g / L, respectively. The production of TZ-249 increased by 3.77%, and the conversion rate of glucose to 1,3-dihydroxyacetone increased slightly to 0.96 mol / mol (Table 2).

[0057] Table 2 shows the shake flask fermentation of 1,3-dihydroxyacetone produced by recombinant E. coli TZ-237 and TZ-249

[0058] strain 1,3-Dihydroxyacetone(g / L) Conversion rate (mol / mol) TZ-237 12.99±0.06 0.95±0.009 TZ-249 13.48±0.14 0.96±0.009

[0059] Example 3: Fermentation of recombinant Escherichia coli TZ-237 in a 5 L fermenter

[0060] Seed culture medium: same as in Example 1.

[0061] CM9 fermentation medium: same as in Example 1.

[0062] Fermentation culture: The recombinant Escherichia coli TZ-237 monoclone on the LB plate was transferred to 2ml seed culture medium and cultured at 37℃ and 250rpm for 18h to obtain seed culture solution. On the second day, 2mL of seed culture solution was transferred to a 1L conical flask containing 100mL of fresh LB culture medium, placed in a constant temperature shaker at 37℃ and 250rpm for culture, and when the seed solution grew to OD600 of 2-3, it was added to a 5L fermenter containing 2L CM9 fermentation medium for fermentation culture. During the fermentation process, 700g / L glucose was used as feed and ammonia water was used as a neutralizer. The fermentation conditions were that the OD600nm of the starting bacteria in the fermentation system was 0.1, the temperature was 37℃, the pH was 7.0, the dissolved oxygen was 30%, the upper limit of the ventilation flow was 10L / min, the lower limit was 3L / min, the upper limit of the stirring speed was 1000r / min, and the lower limit was 300r / min. After inoculation, the dissolved oxygen content was controlled by controlling the dissolved oxygen, stirring speed, and ventilation cascade.

[0063] The culture products obtained at different fermentation times were collected; the culture products were centrifuged at 10000 g for 2 min, and the supernatant was collected.

[0064] The supernatant was analyzed by HPLC for 1,3-dihydroxyacetone production (ie, DHA concentration in the supernatant of the fermentation broth, the detection method was the same as that in Example 2).

[0065] The calculation method of production rate is: production rate = 1,3-dihydroxyacetone concentration / fermentation time (g / L / h)

[0066] The recombinant E. coli TZ-237 was fermented in a 5L tank. The fermentation results were as follows Figure 2 It was shown that after 36 h of fermentation, the yield of 1,3-dihydroxyacetone reached 40.6 g / L, the production rate reached 1.13 g / L / h, and the conversion rate of glucose to 1,3-dihydroxyacetone was 0.95 mol / mol (see Table 3).

[0067] Example 4: Fermentation of recombinant Escherichia coli TZ-249 in a 5 L fermenter

[0068] Seed culture medium: same as in Example 1.

[0069] CM9 fermentation medium: same as in Example 1.

[0070] Fermentation culture: The recombinant Escherichia coli TZ-249 monoclone on the LB plate was transferred to 2ml seed culture medium and cultured at 37℃ and 250rpm for 18h to obtain seed culture solution. On the second day, 2mL of seed culture solution was transferred to a 1L conical flask containing 100mL fresh LB culture medium, placed in a constant temperature shaker at 37℃ and 250rpm for culture. When the seed solution grew to OD600nm of 2-3, it was added to a 5L fermenter containing 2L CM9 fermentation medium for fermentation culture. During the fermentation process, 700g / L glucose was used as feed and ammonia water was used as a neutralizer. The fermentation conditions were that the starting bacteria OD600nm in the fermentation system was 0.1, the temperature was 37℃, the pH was 7.0, the dissolved oxygen was 30%, the upper limit of the ventilation flow was 10L / min, the lower limit was 3L / min, the upper limit of the stirring speed was 1000r / min, and the lower limit was 300r / min. After inoculation, the dissolved oxygen content was controlled by controlling the dissolved oxygen, stirring speed, and ventilation cascade.

[0071] The culture products obtained at different fermentation times were collected; the culture products were centrifuged at 10000 g for 2 min, and the supernatant was collected.

[0072] The supernatant was analyzed by HPLC for 1,3-dihydroxyacetone yield (the same method as in Example 2).

[0073] The calculation method of production rate is: production rate = 1,3-dihydroxyacetone concentration / fermentation time (g / L / h)

[0074] The recombinant E. coli TZ-249 was fermented for 5 L, and the fermentation results were as follows Figure 3 It was shown that after 36 h of fermentation, the yield of 1,3-dihydroxyacetone reached 103.1 g / L, the production rate reached 2.86 g / L / h, and the conversion rate of glucose to 1,3-dihydroxyacetone was 0.99 mol / mol (see Table 3).

[0075] Table 3 shows the 5L fermentation results of recombinant E. coli TZ-237 and TZ-249 for producing 1,3-dihydroxyacetone

[0076]

[0077] Based on the results shown in Examples 2-4 above, it can be seen that the recombinant E. coli TZ-249 obtained by evolutionary metabolism from recombinant E. coli TZ-237 has a greatly improved ability to produce 1,3-dihydroxyacetone, and the strain's tolerance to 1,3-dihydroxyacetone is significantly improved. This is undoubtedly of great significance for large-scale industrial production of 1,3-dihydroxyacetone.

[0078] The present invention has been described in detail above. It will be apparent to those skilled in the art that the present invention may be implemented in a wide range under equivalent parameters, concentrations and conditions without departing from the spirit and scope of the present invention and without the need for unnecessary experimentation. Although the present invention provides specific embodiments, it should be understood that further improvements may be made to the present invention. In short, according to the principles of the present invention, this application intends to include any changes, uses or improvements to the present invention, including changes made by conventional techniques known in the art that depart from the scope disclosed in this application. Applications of some of the basic features may be made within the scope of the following appended claims.

Claims

1. Escherichia coli TZ-249, whose deposit number is CGMCC No.26177.

2. A bacterial agent, wherein the active ingredient is the Escherichia coli TZ-249 or its bacterial liquid or culture liquid or fermentation liquid as claimed in claim 1.

3. Use of TZ-249 or its bacterial solution or culture solution or fermentation solution as described in claim 1 or the bacterial agent as described in claim 2 in at least one of the following: 1) Production of 1,3-dihydroxyacetone; 2) Increase the yield of 1,3-dihydroxyacetone; 3) Increase the production rate of 1,3-dihydroxyacetone; 4) Promote the conversion of glucose into 1,3-dihydroxyacetone.

4. A method for producing 1,3-dihydroxyacetone, comprising the following steps: fermenting and culturing the Escherichia coli TZ-249 according to claim 1 to obtain 1,3-dihydroxyacetone.

5. The method according to claim 4, characterized in that: The fermentation culture uses glucose as a carbon source to produce 1,3-dihydroxyacetone.

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