Heterologous Biosynthesis of Taxifolin in Yarrowia lipolytica: Metabolic Engineering and Genome-Scale Metabolic Modeling.

Taxifolin, also known as dihydroquercetin (DHQ), is a flavonoid recognized for its potent antioxidant properties and a wide range of biological activities, including anti-tumor, antiviral, and immunomodulatory effects. Conventional extraction and chemical synthesis methods for taxifolin are often limited by low yields and associated environmental concerns. In this study, we investigated the heterologous biosynthesis of taxifolin in Yarrowia lipolytica through a combination of metabolic engineering and genome-scale metabolic modeling (GSM), complemented by flux balance analysis (FBA).

Enzyme and Pathway Engineering for Improved Betanin Production in .

Betanin is a water-soluble red-violet pigment belonging to the betacyanins family. It has become more and more attractive for its natural food colorant properties and health benefits. However, the commercial production of betanin, typically extracted from red beetroot, faces economic and sustainability challenges.

Efficient conversion of aromatic and phenylpropanoid alcohols to acids by the cascade biocatalysis of alcohol and aldehyde dehydrogenases.

Benzyl and phenylpropanoid acids are widely used in organic synthesis of fine chemicals, such as pharmaceuticals and condiments. However, biocatalysis of these acids has received less attention than chemical synthesis. One of the main challenges for biological production is the limited availability of alcohol dehydrogenases and aldehyde dehydrogenases.

PAS domain containing regulator SLCG_7083 involved in morphological development and glucose utilization in Streptomyces lincolnensis.

Background: Streptomyces lincolnensis is well known for producing the clinically important antimicrobial agent lincomycin. The synthetic and regulatory mechanisms on lincomycin biosynthesis have been deeply explored in recent years. However, the regulation involved in primary metabolism have not been fully addressed.

Design and deep learning of synthetic B-cell-specific promoters.

Synthetic biology and deep learning synergistically revolutionize our ability for decoding and recoding DNA regulatory grammar. The B-cell-specific transcriptional regulation is intricate, and unlock the potential of B-cell-specific promoters as synthetic elements is important for B-cell engineering. Here, we designed and pooled synthesized 23 640 B-cell-specific promoters that exhibit larger sequence space, B-cell-specific expression, and enable diverse transcriptional patterns in B-cells.

YLC-assembly: large DNA assembly via yeast life cycle.

As an enabling technique of synthetic biology, the scale of DNA assembly largely determines the scale of genetic manipulation. However, large DNA assembly technologies are generally cumbersome and inefficient. Here, we developed a YLC (yeast life cycle)-assembly method that enables in vivo iterative assembly of large DNA by nesting cell-cell transfer of assembled DNA in the cycle of yeast mating and sporulation.

Metabolic Engineering for Efficient Production of Z,Z-Farnesol in .

Z,Z-farnesol (Z,Z-FOH), the all- isomer of farnesol, holds enormous potential for application in cosmetics, daily chemicals, and pharmaceuticals. In this study, we aimed to metabolically engineer to produce Z,Z-FOH. First, we tested five Z,Z-farnesyl diphosphate (Z,Z-FPP) synthases that catalyze neryl diphosphate to form Z,Z-FPP in .

Improvement of betanin biosynthesis in by metabolic engineering.

Betanin is a member of natural pigment betacyanins family and has extensive application in the food industry as an important natural red food colorant. Its relatively inefficient production in nature however hampers access to this phytochemicals through traditional crop-based manufacturing. Microbial bioproduction therefore represents an attractive alternative.

Diversification of phenolic glucosides by two UDP-glucosyltransferases featuring complementary regioselectivity.

Background: Glucoside natural products have been showing great medicinal values and potentials. However, the production of glucosides by plant extraction, chemical synthesis, and traditional biotransformation is insufficient to meet the fast-growing pharmaceutical demands. Microbial synthetic biology offers promising strategies for synthesis and diversification of plant glycosides.

Modular Engineering of for De Novo Biosynthesis of Genistein.

Genistein, a nutraceutical isoflavone, has various pharmaceutical and biological activities which benefit human health via soy-containing food intake. This study aimed to construct to produce genistein from sugar via a modular engineering strategy. In the midstream module, various sources of chalcone synthases and chalcone isomerase-like proteins were tested which enhanced the naringenin production from -coumaric acid by decreasing the formation of the byproduct.

Systems Metabolic Engineering of Coculture for Production of Genistein.

Genistein is a plant-derived isoflavone possessing various bioactivities to prevent aging, carcinogenesis, and neurodegenerative and inflammation diseases. As a typical complex flavonoid, its microbial production from sugar remains to be completed. Here, we use systems metabolic engineering stategies to design and develop a three-strain commensalistic coculture that for the first time realized the production of genistein.

Modular engineering of coculture for efficient production of resveratrol from glucose and arabinose mixture.

Resveratrol, a valuable plant-derived polyphenolic compound with various bioactivities, has been widely used in nutraceutical industries. Microbial production of resveratrol suffers from metabolic burden and low malonyl-CoA availability, which is a big challenge for synthetic biology. Herein, we took advantage of coculture engineering and divided the biosynthetic pathway of resveratrol into the upstream and downstream strains.

Metabolic Division in an Coculture System for Efficient Production of Kaempferide.

Kaempferide, a plant-derived natural flavonoid, exhibits excellent pharmacological activities with nutraceutical and medicinal applications in human healthcare. Efficient microbial production of complex flavonoids suffers from metabolic crosstalk and burden, which is a big challenge for synthetic biology. Herein, we identified 4'--methyltransferases and divided the artificial biosynthetic pathway of kaempferide into upstream, midstream, and downstream modules.

Combinational quorum sensing devices for dynamic control in cross-feeding cocultivation.

Quorum sensing (QS) offers cell density dependent dynamic regulations in cell culture through devices such as synchronized lysis circuit (SLC) and metabolic toggle switch (MTS). However, there is still a lack of studies on cocultivation with a combination of different QS-based devices. Taking the production of isopropanol and salidroside as case studies, we have mathematically modeled a comprehensive set of QS-regulated cocultivation schemes and constructed experimental combinations of QS devices, respectively, to evaluate their feasibility and optimality for regulating growth competition and corporative production.

Plasticity engineering of plant monoterpene synthases and application for microbial production of monoterpenoids.

Plant monoterpenoids with structural diversities have extensive applications in food, cosmetics, pharmaceuticals, and biofuels. Due to the strong dependence on the geographical locations and seasonal annual growth of plants, agricultural production for monoterpenoids is less effective. Chemical synthesis is also uneconomic because of its high cost and pollution.

Metabolic engineering of Escherichia coli for de novo production of 3-phenylpropanol via retrobiosynthesis approach.

Background: 3-Phenylpropanol with a pleasant odor is widely used in foods, beverages and cosmetics as a fragrance ingredient. It also acts as the precursor and reactant in pharmaceutical and chemical industries. Currently, petroleum-based manufacturing processes of 3-phenypropanol is environmentally unfriendly and unsustainable.

Combining Metabolic and Monoterpene Synthase Engineering for Production of Monoterpene Alcohols in .

The monoterpene alcohols acyclic nerol and bicyclic borneol are widely applied in the food, cosmetic, and pharmaceutical industries. The emerging synthetic biology enables microbial production to be a promising alternative for supplying monoterpene alcohols in an efficient and sustainable approach. In this study, we combined metabolic and plant monoterpene synthase engineering to improve the production of nerol and borneol in prene-overproducing .

Compartmentalized Reconstitution of Post-qualene Pathway for 7-Dehydrocholesterol Overproduction in .

7-Dehydrocholesterol (7-DHC) is the direct precursor to manufacture vitamin D. Our previous study has achieved 7-DHC synthesis in based on the endogenous post-squalene pathway. However, the distribution of post-squalene enzymes between the endoplasmic reticulum (ER) and lipid bodies (LD) might raise difficulties for ERG proteins to catalyze and deliver sterol intermediates, resulting in unbalanced metabolic flow and low product yield.

Integrative Biosynthetic Gene Cluster Mining to Optimize a Metabolic Pathway to Efficiently Produce l-Homophenylalanine in .

Mining biosynthetic genes for the exploration of hybrid metabolic pathways is a promising approach in heterologous production of natural and unnatural products. Here, we developed an integrative biosynthetic gene cluster (BGC) mining strategy to engineer the biosynthesis of l-homophenylalanine (l-Hph), an important intermediate for the synthesis of angiotensin-converting enzyme inhibitors. We assembled the putative l-Hph BGCs and integrated phylogenetic analysis with target metabolite abundance mapping to prioritize candidate BGCs.

Metabolic Engineering of for de Novo Production of Betaxanthins.

Betalains are emerging natural pigments with high tinctorial strength and stability, physiological activities, and fluorescent properties for potential application in food, cosmetic, and pharmaceutical industries. Betalains including yellow betaxanthins and red betacyanins are mainly restricted in the Caryophyllales plants. To expand the availability of individual betaxanthins, here, we constructed an BTA6 for de novo biosynthesis of betalamic acid.

Regulatory Patterns of Crp on Monensin Biosynthesis in .

Monensin, produced by Streptomyces cinnamonensis, is a polyether ionophore antibiotic widely used as a coccidiostat and a growth-promoting agent in agricultural industry. In this study, cyclic AMP receptor protein (Crp), the global transcription factor for regulation of monensin biosynthesis, was deciphered. The overexpression and antisense RNA silencing of crp revealed that Crp plays a positive role in monensin biosynthesis.

Comparative transcriptomic analysis reveals the significant pleiotropic regulatory effects of LmbU on lincomycin biosynthesis.

Background: Lincomycin, produced by Streptomyces lincolnensis, is a lincosamide antibiotic and widely used for the treatment of the infective diseases caused by Gram-positive bacteria. The mechanisms of lincomycin biosynthesis have been deeply explored in recent years. However, the regulatory effects of LmbU that is a transcriptional regulator in lincomycin biosynthetic (lmb) gene cluster have not been fully addressed.

Harnessing Yeast Peroxisomes and Cytosol Acetyl-CoA for Sesquiterpene α-Humulene Production.

Metabolic engineering of focusing on the cytoplasm for sustainable terpenoid production is commonly practiced. However, engineering organelles for terpenoid production is rarely reported. Herein, peroxisomes, together with the cytoplasm, were engineered to boost sesquiterpene α-humulene synthesis in .

Metabolic engineering for efficient production of icariside D2.

Background: Icariside D2 is a plant-derived natural glycoside with pharmacological activities of inhibiting angiotensin-converting enzyme and killing leukemia cancer cells. Production of icariside D2 by plant extraction and chemical synthesis is inefficient and environmentally unfriendly. Microbial cell factory offers an attractive route for economical production of icariside D2 from renewable and sustainable bioresources.

Alpha-Terpineol production from an engineered Saccharomyces cerevisiae cell factory.

Background: Alpha-Terpineol (α-Terpineol), a C monoterpenoid alcohol, is widely used in the cosmetic and pharmaceutical industries. Construction Saccharomyces cerevisiae cell factories for producing monoterpenes offers a promising means to substitute chemical synthesis or phytoextraction.

Results: α-Terpineol was produced by expressing the truncated α-Terpineol synthase (tVvTS) from Vitis vinifera in S.