A comparative study of acupuncture combined with rehabilitation gymnastics on postoperative anal function of lower rectal cancer.

BACKGROUND: From the anal function, inflammatory response and other indicators, acupuncture combined with rehabilitation gymnastics was applied to patients with cancer undergoing low resection, aiming to improve the prognosis of patients. AIM: To explore the effects of acupuncture combined with rehabilitation gymnastics on anal function after lower rectal cancer surgery. METHODS: From January 2020 to December 2022, 128 patients who underwent rectal cancer surgery in the Department of Oncology of Hebei Provincial Hospital of Traditional Chinese Medicine Hospital were selected and divided into two groups using the random number table method, with 64 patients in each group. Patients in the control group were not treated with acupuncture or rehabilitation gymnastics and served as blank controls. Patients in the study group were treated with acupuncture and rehabilitation gymnastics from the 7th postoperative day. The anal incontinence scores, changes in serum interleukin-4, interleukin-6, and interleukin-10 Levels, and serum motilin, 5-hydroxytryptamine, and vasoactive intestinal peptide levels were compared. RESULTS: There were no significant differences in serum interleukin-4, interleukin-6, and interleukin-10 Levels between the groups before treatment (P > 0.05). After treatment, these levels were better than those of the control group (P < 0.05). There was no significant difference in the anal incontinence scores between the groups before and 7 d after surgery (P > 0.05). Anal incontinence scores in the study group were lower than those in the control group at 14 d, 21 d, and 28 d postoperatively (P < 0.05). There were no significant differences in serum motilin, 5-hydroxytryptamine, or vasoactive intestinal peptide levels between the groups before treatment (P > 0.05). After treatment, these levels were higher in the study group than in the control group, and vasoactive intestinal peptide level was lower in the study group than in the control group (P < 0.05). CONCLUSION: Acupuncture combined with rehabilitation gymnastics can promote the recovery of anal function and reduce the inflammatory response in patients with lower rectal cancer after surgery.

Evaluating the clinical application and effect of acupuncture therapy in anal function rehabilitation after low-tension rectal cancer surgery.

BACKGROUND: According to the indexes of serum and anal function, acupuncture therapy was applied to patients with low rectal cancer in order to avoid the occurrence of anal incontinence and reduce complications. AIM: To explore the clinical application and evaluate the effect of acupuncture therapy for anal function rehabilitation after low-tension rectal cancer surgery. METHODS: From the anorectal surgery cases, we selected 120 patients who underwent colorectal cancer surgery between January 2020 and December 2022 and randomly divided them into a control group (n = 60), observation group (n = 60), and control group after surgery for lifestyle intervention (including smoking cessation and exercise), dietary factor adjustment, anal movement, and oral loperamide treatment. The serum levels of motilin, 5-hydroxytryptamine, and vasoactive intestinal peptide (VIP), Wexner score for anal incontinence, and incidence of complications were compared between groups. RESULTS: After treatment, the VIP and 5-hydroxytryptamine levels in the observation group were lower than those in the control group (P < 0.05). The motilin level was higher than that in the control group (P < 0.05). Postoperative anal incontinence was better in the observation group than in the control group (P < 0.05). The incidence of complications in the observation group was 6.67%, which was significantly lower than that in the control group (21.67%; P < 0.05). CONCLUSION: Acupuncture therapy has a positive effect on the rehabilitation of anal function after low-tension rectal cancer surgery; it can effectively help to improve the serum indices of patients, avoid the occurrence of anal incontinence, and reduce the incidence of complications. Popularizing and applying it will be valuable.

Combinatorial metabolic engineering of Bacillus subtilis for menaquinone-7 biosynthesis.

Menaquinone-7 (MK-7), a form of vitamin K2, supports bone health and prevents arterial calcification. Microbial fermentation for MK-7 production has attracted widespread attention because of its low cost and short production cycles. However, insufficient substrate supply, unbalanced precursor synthesis, and low catalytic efficiency of key enzymes severely limited the efficiency of MK-7 synthesis. In this study, utilizing Bacillus subtilis BSAT01 (with an initial MK-7 titer of 231.0 mg/L) obtained in our previous study, the glycerol metabolism pathway was first enhanced to increase the 3-deoxy-arabino-heptulonate 7-phosphate (DHAP) supply, which led to an increase in MK-7 titer to 259.7 mg/L. Subsequently, a combination of knockout strategies predicted by the genome-scale metabolic model etiBsu1209 was employed to optimize the central carbon metabolism pathway, and the resulting strain showed an increase in MK-7 production from 259.7 to 318.3 mg/L. Finally, model predictions revealed the methylerythritol phosphate pathway as the major restriction pathway, and the pathway flux was increased by heterologous introduction (Introduction of Dxs derived from Escherichia coli) and fusion expression (End-to-end fusion of two enzymes by a linker peptide), resulting in a strain with a titer of 451.0 mg/L in a shake flask and 474.0 mg/L in a 50-L bioreactor. This study achieved efficient MK-7 synthesis in B. subtilis, laying the foundation for large-scale MK-7 bioproduction.

Formation of iron-rich encrustation layer on anammox granules for high load stress resistance: Performance, advantages, and mechanisms.

Anaerobic ammonia oxidation (anammox) is a cost-effective technology but its performance can be seriously inhibited by high load stress. This study has created an innovative iron-rich encrustation layer (IEL) on the surface of anammox granules (AnGS) through the addition of a certain amount of nano zero-valent iron. The IEL was formed through the aggregation of a gel network and the binding of iron species with extracellular polymeric substances (EPS), resulting in a significant increase in settling ability, EPS secretion, and heme content. Metagenomic analysis indicated a notable rise in the functional genes associated with nitrogen andiron metabolism in IEL AnGS. Under high load stress, the ammonia removal performance of AnGS without IEL severely declined. In contrast, IEL AnGS exhibited excellent ammonia removal efficiency of over 90%. The IEL served as a protective barrier for AnGS, effectively mitigating the strong shear forces, thereby enhancing their resistance to high load stress.

Exploring new frontiers: a rare case of catheter ablation for persistent atrial fibrillation in a patient with cor triatriatum sinister guided by intracardiac echocardiography.

BACKGROUND: Cor triatriatum sinister (CTS) is an uncommon congenital cardiac anomaly. Atrial fibrillation (AF) is commonly the initial symptom in patients with CTS, occurring in approximately 32% of the cases. The complexity of performing AF catheter ablation, particularly in cases with persistent AF, increases in patients with CTS due to its unique structural challenges. CASE PRESENTATION: We report the treatment course of a 60-year-old male patient diagnosed with CTS, who underwent catheter ablation of drug-refractory, persistent AF. The complex anatomical structure of the condition made catheter ablation of AF challenging. To navigate these challenges, we performed comprehensive assessments using transthoracic echocardiography and transesophageal echocardiography, along with cardiac computed tomography angiography, prior to treatment initiation. The intricate anatomy of CTS was further clarified during the procedure via intracardiac echocardiography (ICE). Additionally, the complexity of catheter manipulation was further reduced with the aid of the VIZIGO sheath and the vein of Marshall ethanol infusion to achieve effective mitral isthmus blockage, thereby circumventing the impact of the CTS membrane. CONCLUSIONS: This case underscores the complexity and potential of advanced ablation techniques in managing cardiac arrhythmias associated with unusual cardiac anatomies. During the procedure, ICE facilitated detailed modeling of the left atrium, including the membranous structure and its openings, thus providing a clearer understanding of CTS. It is noteworthy that the membrane within the CTS may serve as a potential substrate for arrhythmias, which warrants further validation through larger sample studies.

CPT1A loss disrupts BCAA metabolism to confer therapeutic vulnerability in TP53-mutated liver cancer.

Driver genomic mutations in tumors define specific molecular subtypes that display distinct malignancy competence, therapeutic resistance and clinical outcome. Although TP53 mutation has been identified as the most common mutation in hepatocellular carcinoma (HCC), current understanding on the biological traits and therapeutic strategies of this subtype has been largely unknown. Here, we reveal that fatty acid ß oxidation (FAO) is remarkable repressed in TP53 mutant HCC and which links to poor prognosis in HCC patients. We further demonstrate that carnitine palmitoyltransferase 1 (CPT1A), the rate-limiting enzyme of FAO, is universally downregulated in liver tumor tissues, and which correlates with poor prognosis in HCC and promotes HCC progression in the de novo liver tumor and xenograft tumor models. Mechanically, hepatic Cpt1a loss disrupts lipid metabolism and acetyl-CoA production. Such reduction in acetyl-CoA reduced histone acetylation and epigenetically reprograms branched-chain amino acids (BCAA) catabolism, and leads to the accumulation of cellular BCAAs and hyperactivation of mTOR signaling. Importantly, we reveal that genetic ablation of CPT1A renders TP53 mutant liver cancer mTOR-addicted and sensitivity to mTOR inhibitor AZD-8055 treatment. Consistently, Cpt1a loss in HCC directs tumor cell therapeutic response to AZD-8055. CONCLUSION: Our results show genetic evidence for CPT1A as a metabolic tumor suppressor in HCC and provide a therapeutic approach for TP53 mutant HCC patients.

[The expression and secretion of human lactoferrin in Bacillus subtilis].

Human lactoferrin (HLF), an essential nutrient found in breast milk, possesses antibacterial, anti-inflammatory, and immune-enhancing properties. In this study, the effects of three constitutive promoters (P21, P43, and Pveg) and three inducible promoters (Pgrac100, PxylA, and Ptet*) on the expression of HLF were compared using Bacillus subtilis G601 as the host strain. The results showed that the highest expression of HLF, reaching 651.57 µg/L, was achieved when regulated by the Ptet* promoter. Furthermore, the combinational optimization of ribosome binding site (RBS) and signal peptides was investigated, and the optimal combination of RBS6 and SPyycP resulted in increased HLF expression to 1 099.87 µg/L, with 498.68 µg/L being secreted extracellularly. To further enhance HLF secretion, the metal cations-related gene dltD was knocked out, leading to an extracellular HLF level of 637.28 µg/L. This study successfully demonstrated the secretory expression of HLF in B. subtilis through the selection and optimization of expression elements, laying the foundation for the development of efficient B. subtilis cell factories for lactoprotein synthesis.

Protein O-fucosyltransferase 1 promotes PD-L1 stability to drive immune evasion and directs liver cancer to immunotherapy.

BACKGROUND AND AIMS: The immunosuppressive tumor microenvironment (TME) plays an essential role in cancer progression and immunotherapy response. Despite the considerable advancements in cancer immunotherapy, the limited response to immune checkpoint blockade (ICB) therapies in patients with hepatocellular carcinoma (HCC) remains a major challenge for its clinical implications. Here, we investigated the molecular basis of the protein O-fucosyltransferase 1 (POFUT1) that drives HCC immune evasion and explored a potential therapeutic strategy for enhancing ICB efficacy. METHODS: De novo MYC/Trp53-/- liver tumor and the xenograft tumor models were used to evaluate the function of POFUT1 in immune evasion. Biochemical assays were performed to elucidate the underlying mechanism of POFUT1-mediated immune evasion. RESULTS: We identified POFUT1 as a crucial promoter of immune evasion in liver cancer. Notably, POFUT1 promoted HCC progression and inhibited T-cell infiltration in the xenograft tumor and de novo MYC/Trp53-/- mouse liver tumor models. Mechanistically, we demonstrated that POFUT1 stabilized programmed death ligand 1 (PD-L1) protein by preventing tripartite motif containing 21-mediated PD-L1 ubiquitination and degradation independently of its protein-O-fucosyltransferase activity. In addition, we further demonstrated that PD-L1 was required for the tumor-promoting and immune evasion effects of POFUT1 in HCC. Importantly, inhibition of POFUT1 could synergize with anti-programmed death receptor 1 therapy by remodeling TME in the xenograft tumor mouse model. Clinically, POFUT1 high expression displayed a lower response rate and worse clinical outcome to ICB therapies. CONCLUSIONS: Our findings demonstrate that POFUT1 functions as a novel regulator of tumor immune evasion and inhibition of POFUT1 may be a potential therapeutic strategy to enhance the efficacy of immune therapy in HCC.

Combinatorial Engineering of Escherichia coli for Enhancing 3-Fucosyllactose Production.

3-Fucosyllactose (3-FL) is an important fucosylated human milk oligosaccharide (HMO) with biological functions such as promoting immunity and brain development. Therefore, the construction of microbial cell factories is a promising approach to synthesizing 3-FL from renewable feedstocks. In this study, a combinatorial engineering strategy was used to achieve efficient de novo 3-FL production in Escherichia coli. α-1,3-Fucosyltransferase (futM2) from Bacteroides gallinaceum was introduced into E. coli and optimized to create a 3-FL-producing chassis strain. Subsequently, the 3-FL titer increased to 5.2 g/L by improving the utilization of the precursor lactose and down-regulating the endogenous competitive pathways. Furthermore, a synthetic membraneless organelle system based on intrinsically disordered proteins was designed to spatially regulate the pathway enzymes, producing 7.3 g/L 3-FL. The supply of the cofactors NADPH and GTP was also enhanced, after which the 3-FL titer of engineered strain E26 was improved to 8.2 g/L in a shake flask and 10.8 g/L in a 3 L fermenter. In this study, we developed a valuable approach for constructing an efficient 3-FL-producing cell factory and provided a versatile workflow for other chassis cells and HMOs.

Discovery of novel cholesteryl ester transfer protein (CETP) inhibitors by a multi-stage virtual screening.

Cholesteryl ester transfer protein (CETP) is a promising therapeutic target for cardiovascular diseases. It effectively lowers the low-density lipoprotein cholesterol levels and increases the high-density lipoprotein cholesterol levels in the human plasma. This study identified novel and highly potent CETP inhibitors using virtual screening techniques. Molecular docking and molecular dynamics (MD) simulations revealed the binding patterns of these inhibitors, with the top 50 compounds selected according to their predicted binding affinity. Protein-ligand interaction analyses were performed, leading to the selection of 26 compounds for further evaluation. A CETP inhibition assay confirmed the inhibitory activities of the selected compounds. The results of the MD simulations revealed the structural stability of the protein-ligand complexes, with the binding site remaining significantly unchanged, indicating that the five compounds (AK-968/40709303, AG-690/11820117, AO-081/41378586, AK-968/12713193, and AN-465/14952302) identified have the potential as active CETP inhibitors and are promising leads for drug development.

Genome-wide characterization of Remorin gene family and their responsive expression to abiotic stresses and plant hormone in Brassica napus.

KEY MESSAGE: Remorin proteins could be positively related to salt and osmotic stress resistance in rapeseed. Remorins (REMs) play a crucial role in adaptations to adverse environments. However, their roles in abiotic stress and phytohormone responses in oil crops are still largely unknown. In this study, we identified 47 BnaREM genes in the B.napus genome. Phylogenetic relationship and synteny analysis revealed that they were categorized into 5 distinct groups and have gone through 55 segmental duplication events under purifying selection. Gene structure and conserved domains analysis demonstrated that they were highly conserved and all BnaREMs contained a conserved Remorin_C domain, with a variable N-terminal region. Promoter sequence analysis showed that BnaREM gene promoters contained various hormones and stress-related cis-acting elements. Transcriptome data from BrassicaEDB database exhibited that all BnaREMs were ubiquitously expressed in buds, stamens, inflorescences, young leaves, mature leaves, roots, stems, seeds, silique pericarps, embryos and seed coats. The qRT-PCR analysis indicated that most of them were responsive to ABA, salt and osmotic treatments. Further mutant complementary experiments revealed that the expression of BnaREM1.3-4C-1 in the Arabidopsis rem1.3 mutant restored the retarded growth phenotype and the ability to resistance to salt and osmotic stresses. Our findings provide fundamental information on the structure and evolutionary relationship of the BnaREM family genes in rapeseed, and reveal the potential function of BnaREM1.3-4C-1 in stress and hormone response.

Combinatorial Metabolic Engineering for Improving Betulinic Acid Biosynthesis in Saccharomyces cerevisiae.

Betulinic acid (BA) is a lupane-type triterpenoid with potent anticancer and anti-HIV activities. Its great potential in clinical applications necessitates the development of an efficient strategy for BA synthesis. This study attempted to achieve efficient BA biosynthesis in Saccharomyces cerevisiae using systematic metabolic engineering strategies. First, a de novo BA biosynthesis pathway in S. cerevisiae was constructed, which yielded a titer of 14.01 ± 0.21 mg/L. Then, by enhancing the BA synthesis pathway and dynamic inhibition of the competitive pathway, a greater proportion of the metabolic flow was directed toward BA synthesis, achieving a titer of 88.07 ± 5.83 mg/L. Next, acetyl-CoA and NADPH supply was enhanced, which increased the BA titer to 166.43 ± 1.83 mg/L. Finally, another BA synthesis pathway in the peroxisome was constructed. Dual regulation of the peroxisome and cytoplasmic metabolism increased the BA titer to 210.88 ± 4.76 mg/L. Following fed-batch fermentation process modification, the BA titer reached 682.29 ± 8.16 mg/L. Overall, this work offers a guide for building microbial cell factories that are capable of producing terpenoids with efficiency.

Facilitating stable gene integration expression and copy number amplification in Bacillus subtilis through a reversible homologous recombination switch.

Strengthening the expression level of integrated genes on the genome is crucial for consistently expressing key enzymes in microbial cell factories for efficient bioproduction in synthetic biology. In comparison to plasmid-based multi-copy expression, the utilization of chromosomal multi-copy genes offers increased stability of expression level, diminishes the metabolic burden on host cells, and enhances overall genetic stability. In this study, we developed the "BacAmp", a stabilized gene integration expression and copy number amplification system for high-level expression in Bacillus subtilis, which was achieved by employing a combination of repressor and non-natural amino acids (ncAA)-dependent expression system to create a reversible switch to control the key gene recA for homologous recombination. When the reversible switch is turned on, genome editing and gene amplification can be achieved. Subsequently, the reversible switch was turned off therefore stabilizing the gene copy number. The stabilized gene amplification system marked by green fluorescent protein, achieved a 3-fold increase in gene expression by gene amplification and maintained the average gene copy number at 10 after 110 generations. When we implemented the gene amplification system for the regulation of N-acetylneuraminic acid (NeuAc) synthesis, the copy number of the critical gene increased to an average of 7.7, which yielded a 1.3-fold NeuAc titer. Our research provides a new avenue for gene expression in synthetic biology and can be applied in metabolic engineering in B. subtilis.

Protein of yak milk residue: Structure, functionality, and the effects on the quality of non-fat yogurt.

The purpose of this study was to compare the structural and functional of protein from yak milk residue, which collected from different elevations (MRP1 and MRP2) in Tibet, as well as their potential for enhancing the quality of non-fat yogurt. The results showed that MRP1 exhibited higher levels of ß-sheet, turbidity, particle size, and gel properties. MRP2 had better flexibility, emulsification, foaming, water/oil absorption capacity. The addition of MRP1 (3%) could improve texture and sensory properties of yogurt. Although MRP2 yogurt had higher hardness, gumminess, chewiness and water holding capacity, poor mouthfeel. Rheological test showed that MRPs yogurt exhibited typical gel-like and shear-thinning behavior. Moreover, the fortification of non-fat yogurts with MRP1 brought the formation of larger protein clusters with a more tightly knit network of smaller pores. These results indicate that MRP1 can be used as a fat substitute to improve the quality of non-fat yogurt.

GLI1 polymorphisms influence remission rate and prognosis of young de novo acute myeloid leukemia patients treated with cytarabine-based chemotherapy.

Acute myeloid leukemia (AML) is a highly heterogeneous hematological malignancy. Cytarabine (Ara-C)-based chemotherapy is the primary treatment for AML, but currently known prognostic risk stratification factors cannot fully explain the individual differences in outcome of patients. In this article, we reported that patients with homozygous GLI1 rs2228224 mutation (AA genotype) had a significantly lower complete remission rate than those with GG wild type (54.17% vs.76.02%, OR = 1.993, 95% CI: 1.062-3.504, P = 0.031). GLI1 rs2229300 T allele carriers had remarkably shorter overall survival (513 vs. 645 days, P = 0.004) and disease-free survival (342 vs. 456 days, P = 0.033) than rs2229300 GG carriers. Rs2229300 G > T variation increased the transcriptional activity of GLI1. CCND1, CD44 and PROM1 were potential target genes differentially regulated by GLI1 rs2229300. Our results demonstrated for the first time that GLI1 polymorphisms influence chemosensitivity and prognosis of young de novo AML patients treated with Ara-C.

Constructing an Antibiotic-Free Protein Expression System for Ovalbumin Biosynthesis in Probiotic Escherichia coli Nissle 1917.

Ovalbumin (OVA) is the principal protein constituent of eggs. As an alternative to eggs, cell-cultured OVA can reduce the environmental impact of global warming and land use. Escherichia coli Nissle 1917 (EcN), a probiotic with specific endogenous cryptic plasmids that stably exist in cells without the addition of antibiotics, was chosen as the host for the efficient heterologous expression of the OVA. OVA yield reached 20 mg·L-1 in shake flasks using the OVA expression cassette containing a tac promoter (Ptac) upstream of the OVA-coding sequences on the endogenous plasmid pMUT2. Subsequently, we improved the level of the expression of the OVA by employing a dual promoter (PP5 combined with Ptac via a sigma factor binding site 24) and ribosome binding site (RBS) substitution. These enhancements increased the level of production of OVA in shake flasks to 30 and 42 mg·L-1, respectively. OVA by EcNP-P28 harboring plasmid L28 equipped with both dual promoter and the strong RBS8 reached 3.70 g·L-1 in a 3 L bioreactor. Recombinant OVA and natural OVA showed similar biochemical characteristics, including secondary structure, isoelectric point, amino acid composition, and thermal stability. This is currently the highest OVA production reported among prokaryotes. We successfully constructed an antibiotic-free heterologous protein expression system for EcN.

Teneligliptin mitigates diabetic cardiomyopathy by inhibiting activation of the NLRP3 inflammasome.

BACKGROUND: Diabetic cardiomyopathy (DCM), which is a complication of diabetes, poses a great threat to public health. Recent studies have confirmed the role of NLRP3 (NOD-like receptor protein 3) activation in DCM development through the inflammatory response. Teneligliptin is an oral hypoglycemic dipeptidyl peptidase-IV inhibitor used to treat diabetes. Teneligliptin has recently been reported to have anti-inflammatory and protective effects on myocardial cells. AIM: To examine the therapeutic effects of teneligliptin on DCM in diabetic mice. METHODS: Streptozotocin was administered to induce diabetes in mice, followed by treatment with 30 mg/kg teneligliptin. RESULTS: Marked increases in cardiomyocyte area and cardiac hypertrophy indicator heart weight/tibia length reductions in fractional shortening, ejection fraction, and heart rate; increases in creatine kinase-MB (CK-MB), aspartate transaminase (AST), and lactate dehydrogenase (LDH) levels; and upregulated NADPH oxidase 4 were observed in diabetic mice, all of which were significantly reversed by teneligliptin. Moreover, NLRP3 inflammasome activation and increased release of interleukin-1ß in diabetic mice were inhibited by teneligliptin. Primary mouse cardiomyocytes were treated with high glucose (30 mmol/L) with or without teneligliptin (2.5 or 5 µM) for 24 h. NLRP3 inflammasome activation. Increases in CK-MB, AST, and LDH levels in glucose-stimulated cardiomyocytes were markedly inhibited by teneligliptin, and AMP (p-adenosine 5'-monophosphate)-p-AMPK (activated protein kinase) levels were increased. Furthermore, the beneficial effects of teneligliptin on hyperglycaemia-induced cardiomyocytes were abolished by the AMPK signaling inhibitor compound C. CONCLUSION: Overall, teneligliptin mitigated DCM by mitigating activation of the NLRP3 inflammasome.

Engineering Redox Cofactor Balance for Improved 5-Methyltetrahydrofolate Production in Escherichia coli.

5-Methyltetrahydrofolate (5-MTHF) is the sole active form of folate functioning in the human body and is widely used as a nutraceutical. Unlike the pollution from chemical synthesis, microbial synthesis enables green production of 5-MTHF. In this study, Escherichia coli BL21 (DE3) was selected as the host. Initially, by deleting 6-phosphofructokinase 1 and overexpressing glucose-6-phosphate 1-dehydrogenase and 6-phosphogluconate dehydrogenase, the glycolysis pathway flux decreased, while the pentose phosphate pathway flux enhanced. The ratios of NADH/NAD+ and NADPH/NADP+ increased, indicating elevated NAD(P)H supply. This led to more folate being reduced and the successful accumulation of 5-MTHF to 44.57 µg/L. Subsequently, formate dehydrogenases from Candida boidinii and Candida dubliniensis were expressed, which were capable of catalyzing the reaction of sodium formate oxidation for NAD(P)H regeneration. This further increased the NAD(P)H supply, leading to a rise in 5-MTHF production to 247.36 µg/L. Moreover, to maintain the balance between NADH and NADPH, pntAB and sthA, encoding transhydrogenase, were overexpressed. Finally, by overexpressing six key enzymes in the folate to 5-MTHF pathway and employing fed-batch cultivation in a 3 L fermenter, strain Z13 attained a peak 5-MTHF titer of 3009.03 µg/L, the highest level reported in E. coli so far. This research is a significant step toward industrial-scale microbial 5-MTHF production.