Overproduction of Patchoulol in Metabolically Engineered Komagataella phaffii

Engineering Komagataella phaffii to produce lycopene sustainably from glucose or methanol

Lycopene, a potent carotenoid with high antioxidant capacity and extensive applications, holds significant potential for sustainable production via microbial engineering, particularly with the rising interest in methanol as an ideal non-grain feedstock for a carbon-negative economy. In this study, Komagataella phaffii was systematically engineered to enhance lycopene production using glucose and renewable methanol as alternative carbon sources. Firstly, we demonstrated that the cytoplasmic FPP could penetrate into the peroxisome, and thus achieved the dual-localized lycopene synthesis. Subsequently, the cytoplasmic FPP pool was expanded by dynamically regulating squalene synthase and enhancing the mevalonate pathway, and FPP was redirected to lycopene synthesis via assembling critical enzymes. Furthermore, the synthesis of lycopene from methanol was improved by reprogramming the methanol metabolic pathway. In the above process, we found that the engineered strains would degrade significantly in the process of passing culture. Comparative transcriptomic analysis revealed that nitrogen metabolism genes contributed significantly to strain degeneration, and a gene (PAS_chr2-2_0003) that positively influenced lycopene synthesis was identified. Finally, two strains were successfully engineered: strain zw327, which produced 8.4 g/L lycopene from glucose, and strain zw352, which achieved 10.2 g/L from methanol and glycerol. The latter represents the highest reported titer from methanol to date, underscoring the potential of K. phaffii as a robust one-carbon platform for industrial terpenoid biosynthesis.

Optimizing longifolene production in Yarrowia lipolytica via metabolic and protein engineering

Longifolene (C15H24) is a tricyclic sesquiterpene widely utilized in the cosmetics and fragrances due to its versatile applications. Traditional extraction methods from plants suffer from low titer and lengthy production cycles, while chemical synthesis is hampered by the compound's complex structure, leading to high costs and insufficient market supply. This study aimed to develop a microbial cell factory for enhanced longifolene production. The strategy involved integrating longifolene synthase from Pinus sylvestris (PsTPS) into Yarrowia lipolytica and employing multiple metabolic engineering approaches. Initially, key genes in the mevalonate (MVA) pathway were overexpressed to enhance longifolene precursor availability for longifolene biosynthesis. Subsequently, protein engineering techniques were applied to optimize PsTPS (tPsTPS) for improved catalytic efficiency. Furthermore, co-expression of molecular chaperones was implemented to enhance the synthesis and secretion of PsTPS. The introduction of the isopentenol utilization pathway (IUP) further augmented the supply of C5 substrate. By optimizing the culture conditions, including a reduction in culture temperature, the efflux of longifolene was increased, and the dissolved oxygen levels were enhanced to promote the growth of the strain. These collective efforts resulted culminated in the engineered strain Z03 achieving a noteworthy production level of 34.67 mg/L of longifolene in shake flasks. This study not only demonstrates the feasibility of enhancing sesquiterpene production in Y. lipolytica but also highlights the potential of microbial platforms in meeting industrial demands for complex natural products.

Technological advancement spurs Komagataella phaffii as a next-generation platform for sustainable biomanufacturing

Biomanufacturing stands as a cornerstone of sustainable industrial development, necessitating a shift toward non-food carbon feedstocks to alleviate agricultural resource competition and advance a circular bioeconomy. Methanol, a renewable one‑carbon substrate, has emerged as a pivotal candidate due to its abundance, cost-effectiveness, and high reduction potential, further bolstered by breakthroughs in CO₂ hydrogenation-based synthesis. Capitalizing on this momentum, the methylotrophic yeast Komagataella phaffii has undergone transformative technological upgrades, evolving from a conventional protein expression workhorse into an intelligent bioproduction chassis. This paradigm shift is fundamentally driven by converging innovations across CRISPR-empowered advancement in genome editing and AI-powered metabolic pathway design in K. phaffii. The integration of CRISPR systems with droplet microfluidics high-throughput screening has redefined strain engineering efficiency, achieving much higher editing precision than traditional homologous recombination while compressing the "design-build-test-learn" cycle. Concurrently, machine learning-enhanced genome-scale metabolic models facilitate dynamic flux balancing, enabling simultaneous improvements in product titers, carbon yields, and volumetric productivity. Finally, technological advancement promotes the application of K. phaffii, including directing more efficiently metabolic flux toward nutrient products, and strengthening efficient synthesis of excreted proteins. As DNA synthesis automation and robotic experimentation platforms mature, next-generation breakthroughs in genome modification, cofactor engineering, and AI-guided autonomous evolution will further cement K. phaffii as a next-generation platform for decarbonizing global manufacturing paradigms. This technological trajectory positions methanol-based biomanufacturing as a cornerstone of the low-carbon circular economy.

Recent Advances in Multiple Strategies for the Biosynthesis of Sesquiterpenols

Sesquiterpenols, a class of natural compounds composed of three isoprene units that form a 15-carbon skeleton with hydroxyl (-OH) group, are characterized by their volatility and potent aromatic properties. These compounds exhibit a wide range of biological activities, including antitumor, antibacterial, anti-inflammatory, anti-neurotoxic, antiviral, immunosuppressive, hepatoprotective, and cardiotonic effects. Due to their diverse physiological functionalities, sesquiterpenols serve as critical raw materials in the pharmaceutical, food, and cosmetic industries. In recent years, research on the heterologous synthesis of sesquiterpenol compounds using microbial systems has surged, attracting significant scientific interest. However, challenges such as low yields and high production costs have impeded their industrial-scale application. The rapid development of synthetic biology has introduced innovative methodologies for the microbial production of sesquiterpenol compounds. Herein, we examine the latest synthetic biology strategies and progress in microbial sesquiterpenol production, focusing on adaptive sesquiterpenol synthase screening and expression, synthesis pathway regulation, intracellular compartmentalized expression strategies, and tolerance to terpenoid-related toxicity. Critical challenges and future directions are also discussed to advance research in sesquiterpenol biosynthesis.

Reprogramming Komagataella phaffii for a Robust Chassis toward Efficient De Novo Biosynthesis of (-)-α-Bisabolol

(-)-α-Bisabolol, a monocyclic susquiterpene alcohol, has been widely used in the fields of food, medicine, and biofuel. Recently, the rapid development of synthetic biology has offered a sustainable route for the production of (-)-α-bisabolol by microbial cell factories. Even though efficient biosynthesis of (-)-α-bisabolol has been achieved in Escherichia coli with the highest titer of 23.4 g/L, the possible infection risk by the bacteriophage makes E. coli unsuitable to act as the most robust chassis. Herein, we optimized the MVA pathway of Komagataella phaffii and fused farnesyl diphosphate synthase (ERG20), with bisabolol synthase for efficient production of (-)-α-bisabolol. Through the engineering of cofactor NADPH, molecular chaperone, and transcription factors, we obtained the robust (-)-α-bisabolol-producing strain, KB-30. Finally, the highly efficient production of (-)-α-bisabolol was achieved in a 5 L fed-batch fermenter, giving a titer of 32.8 g/L and a space-time yield of 283 mg/L/h. This work represents the highest production of (-)-α-bisabolol to date and provides new insights for efficient terpenoid biosynthesis.

Development of a Komagataella phaffii cell factory for sustainable production of ( +)-valencene

BACKGROUND

Sesquiterpene ( +)-valencene is a characteristic aroma component from sweet orange fruit, which has a variety of biological activities and is widely used in industrial manufacturing of food, beverage and cosmetics industries. However, at present, the content in plant sources is low, and its yield and quality would be influenced by weather and land, which limit the supply of ( +)-valencene. The rapid development of synthetic biology has accelerated the construction of microbial cell factories and provided an effective alternative method for the production of natural products.

RESULTS

In this study, we first introduced the ( +)-valencene synthase into Komagataella phaffii by CRISPR/Cas9 system, and successfully constructed a ( +)-valencene producer with the initial yield of 2.1 mg/L. Subsequently, the ( +)-valencene yield was increased to 8.2 mg/L by fusing farnesyl pyrophosphate synthase with ( +)-valencene synthase using the selected ligation linker. High expression of key genes IDI1, tHMG1, ERG12 and ERG19 enhanced metabolic flux of MVA pathway, and the yield of ( +)-valencene was further increased by 27%. Besides, in-situ deletion of the promoter of ERG9 increased the yield of ( +)-valencene to 48.1 mg/L. Finally, we optimized the copy number of farnesyl pyrophosphate synthase and ( +)-valencene synthase fusion protein, and when the copy number reached three, the yield of ( +)-valencene achieved 173.6 mg/L in shake flask level, which was 82-fold higher than that of the starting strain CaVAL1.

CONCLUSIONS

The results obtained here suggest that K. phaffii has the potential to efficiently synthesize other terpenoids.

Low-carbon and overproduction of cordycepin from methanol using engineered Pichia pastoris cell factory

Cordycepin, a nucleoside analog, is widely used in medicine and health products. However, the production of cordycepin from Cordyceps militaris faces the challenges of low productivity and high rate of greenhouse gas emissions. In this study, by optimizing the cordycepin biosynthesis pathway through promoter combination, Kozak sequence, and enzyme fusion, enhancing the methanol assimilation capacity in peroxisomes, adjusting the synthesis of NADPH and ATP, and combining the enhanced supply of adenosine and 3'-AMP, the cordycepin high-yield strain Pp29 was constructed, which produced 1551.44 mg/L cordycepin by shake-flask fermentation. In fed-batch fermentation, Pp29 achieved the highest yield (8.11 g/L, 67.64 mg/g DCW, and 1.35 g/L/d) to date in 10 L fermenter, and the CO2-eq emissions were 1.9-17.3 times lower than C. militaris and other yeast systems. This study provide basis for Pichia pastoris to be used as chassis cell for synthesizing cordycepin and other nucleoside analogs by methanol as carbon source.

De novo biosynthesis of β-Arbutin in Komagataella phaffii based on metabolic engineering strategies

BACKGROUND

β-Arbutin, found in the leaves of bearberry, stands out as one of the globally acknowledged eco-friendly whitening additives in recent years. However, the natural abundance of β-Arbutin is low, and the cost-effectiveness of using chemical synthesis or plant extraction methods is low, which cannot meet the requirements. While modifying the β-Arbutin synthesis pathway of existing strains is a viable option, it is hindered by the limited synthesis capacity of these strains, which hinders further development and application.

RESULTS

In this study, we established a biosynthetic pathway in Komagataella phaffii for β-Arbutin production with a titer of 1.58 g/L. Through diverse metabolic strategies, including fusion protein construction, enhancing shikimate pathway flux, and augmenting precursor supplies (PEP, E4P, and UDPG), we significantly increased β-Arbutin titer to 4.32 g/L. Further optimization of methanol concentration in shake flasks led to a titer of 6.32 g/L titer after 120 h of fermentation, representing a fourfold increase over the initial titer. In fed-batch fermentation, strain UA3-10 set a record with the highest production to date, reaching 128.6 g/L in a 5 L fermenter.

CONCLUSIONS

This is the highest yield in the fermentation tank level of using microbial cell factories for de novo synthesis of β-Arbutin. Applying combinatorial engineering strategies has significantly improved the β-Arbutin yield in K. phaffii and is a promising approach for synthesizing functional products using a microbial cell factory. This study not only advances low-cost fermentation-based production of β-Arbutin but also establishes K. phaffii as a promising chassis cell for synthesizing other aromatic amino acid metabolites.

Engineering yeast for high-level production of β-farnesene from sole methanol

Methanol, a rich one-carbon feedstock, can be massively produced from CO2 by the liquid sunshine route, which is helpful to realize carbon neutrality. β-Farnesene is widely used in the production of polymers, surfactants, lubricants, and also serves as a suitable substitute for jet fuel. Constructing an efficient cell factory is a feasible approach for β-farnesene production through methanol biotransformation. Here, we extensively engineered the methylotrophic yeast Ogataea polymorpha for the efficient bio-production of β-farnesene using methanol as the sole carbon source. Our study demonstrated that sufficient supply of precursor acetyl-CoA and cofactor NADPH in an excellent yeast chassis had a 1.3-fold higher β-farnesene production than that of wild-type background strain. Further optimization of the mevalonate pathway and enhancement of acetyl-CoA supply led to a 7-fold increase in β-farnesene accumulation, achieving the highest reported sesquiterpenoids production (14.7 g/L with a yield of 46 mg/g methanol) from one-carbon feedstock under fed-batch fermentation in bioreactor. This study demonstrates the great potential of engineering O. polymorpha for high-level terpenoid production from methanol.

Engineering Yeast Peroxisomes for α-Bisabolene Production from Sole Methanol with the Aid of Proteomic Analysis

Microbial metabolic engineering provides a feasible approach to sustainably produce advanced biofuels and biochemicals from renewable feedstocks. Methanol is an ideal feedstock since it can be massively produced from CO2 through green energy, such as solar energy. However, engineering microbes to transform methanol and overproduce chemicals is challenging. Notably, the microbial production of isoprenoids from methanol is still rarely reported. Here, we extensively engineered Pichia pastoris (syn. Komagataella phaffii) for the overproduction of sesquiterpene α-bisabolene from sole methanol by optimizing the mevalonate pathway and peroxisomal compartmentalization. Furthermore, through label-free quantification (LFQ) proteomic analysis of the engineered strains, we identified the key bottlenecks in the peroxisomal targeting pathway, and overexpressing the limiting enzyme EfmvaE significantly improved α-bisabolene production to 212 mg/L with the peroxisomal pathway. The engineered strain LH122 with the optimized peroxisomal pathway produced 1.1 g/L α-bisabolene under fed-batch fermentation in shake flasks, achieving a 69% increase over that of the cytosolic pathway. This study provides a viable approach for overproducing isoprenoid from sole methanol in engineered yeast cell factories and shows that proteomic analysis can help optimize the organelle compartmentalized pathways to enhance chemical production.

New advances in protein engineering for industrial applications: Key takeaways

Recent advancements in protein/enzyme engineering have enabled the production of a diverse array of high-value compounds in microbial systems with the potential for industrial applications. The goal of this review is to articulate some of the most recent protein engineering advances in bacteria, yeast, and other microbial systems to produce valuable substances. These high-value substances include α-farnesene, vitamin B12, fumaric acid, linalool, glucaric acid, carminic acid, mycosporine-like amino acids, patchoulol, orcinol glucoside, d-lactic acid, keratinase, α-glucanotransferases, β-glucosidase, seleno-methylselenocysteine, fatty acids, high-efficiency β-glucosidase enzymes, cellulase, β-carotene, physcion, and glucoamylase. Additionally, recent advances in enzyme engineering for enhancing thermostability will be discussed. These findings have the potential to revolutionize various industries, including biotechnology, food, pharmaceuticals, and biofuels.

Metabolic Engineering of Candida glycerinogenes for Sustainable Production of Geraniol

Geraniol is a class of natural products that are widely used in the aroma industry due to their unique aroma. Here, to achieve the synthesis of geraniol and alleviate the intense competition from the yeast ergosterol pathway, a transcription factor-mediated ergosterol feedback system was developed in this study to autonomously regulate ergosterol metabolism and redirect carbon flux to geraniol synthesis. In addition, the modification of ergosterol-responsive promoters, the optimization of transcription factor expression intensity, and stepwise metabolic engineering resulted in a geraniol titer of 531.7 mg L-1. For sustainable production of geraniol, we constructed a xylose assimilation pathway in Candida glycerinogenes (C. glycerinogenes). Then, the xylose metabolic capacity was ameliorated and the growth of the engineered strain was rescued by activating the pentose phosphate (PP) pathway. Finally, we obtained 1091.6, 862.4, and 921.8 mg L-1 of geraniol in a 5 L bioreactor by using pure glucose, simulated wheat straw hydrolysates, and simulated sugarcane bagasse hydrolysates, with yields of 47.5, 57.9, and 59.1 mg g-1 DCW, respectively. Our study demonstrated that C. glycerinogenes has the potential to produce geraniol from lignocellulosic biomass, providing a powerful tool for the sustainable synthesis of other valuable monoterpenes.