Engineering Escherichia coli towards de novo production of gatekeeper (2S)-flavanones: naringenin, pinocembrin, eriodictyol and homoeriodictyol

Abstract

Natural plant-based flavonoids have drawn significant attention as dietary supplements due to their potential health benefits, including anti-cancer, anti-oxidant, and anti-asthmatic activities. Naringenin, pinocembrin, eriodictyol and homoeriodictyol are classified as (2S)-flavanones, an important sub-group of naturally-occurring flavonoids, with wide-reaching applications in human health and nutrition. These four compounds occupy a central position as branch point intermediates towards a broad spectrum of naturally occurring flavonoids. Here, we report the development of E. coli production chassis for each of these key gatekeeper flavonoids. Selection of key enzymes, genetic construct design, and the optimization of process conditions resulted in the highest reported titers for naringenin (484 mg/L), improved production of pinocembrin (198 mg/L) and eriodictyol (55 mg/L from caffeic acid), and provided the first example of in vivo production of homoeriodictyol directly from glycerol (17 mg/L). This work provides a springboard for future production of diverse downstream natural and non-natural flavonoid targets.

Reconstruction of a Genome-Scale Metabolic Model of Streptomyces albus J1074: Improved Engineering Strategies in Natural Product Synthesis

“…This highlights that the FSEOF approach is solely based on the metabolic network stoichiometry and does not factor in modes of regulation. Meanwhile, overexpression of the tyrA and aroG genes in Escherichia coli , coding for chorismate synthase/prephenate dehydrogenase (CHORM and PPND) and 3-deoxy-D-arabino-heptulosonate 7-phosphate synthetase (DDPA), yielded increased naringenin production [ 38 ]. While FSEOF applied to Salb -GEM indeed provides effective strategies to facilitate precursor flux from primary metabolism, an important limitation remains the limited detailed information that is available of the heterologous pathway themselves, precluding inclusion in the model.…”

Metabolic Engineering of Microbial Cell Factories for Biosynthesis of Flavonoids: A Review

“…Flavones [13,16,17,19,20]. However, some problems, including the limitation of the availability of pathway genes, the instability of engineered strains, and the low yield of products in the synthesis process, still hinder the microbial production of flavonoids [1].…”

“…In this study, the synthesis of flavonoids in microorganisms was achieved for the first time when PAL (phenylalanine ammonia lyase), CHS (chalcones synthase), and 4CL (4-coumarin-CoA ligase) were engineered in E. coli to produce naringenin and pinocembrin [18]. Since then, more and more enzymes related to flavonoid synthesis from different plants and microorganisms have been discovered and well-characterized [7], and meanwhile, various flavonoid pathways have been reconstituted in microbial species, including E. coli, S. cerevisiae, Streptomyces albus (S. albus), and Streptomyces coelicolor (S. coelicolor), to produce naringenin, eriodyctiol, pinocembrin, anthocyanins, scutellarein, baicalein, myricetin, kaempferol, quercetin, liquiritigenin, resokaempferol, fisetin, and so forth [13,16,17,19,20]. However, some problems, including the limitation of the availability of pathway genes, the instability of engineered strains, and the low yield of products in the synthesis process, still hinder the microbial production of flavonoids [1].…”

In silico design and automated learning to boost next-generation smart biomanufacturing

“…The ability to produce strains for gateway chemicals (e.g. flavanones ( 58 )) with broad applications such as precursors to materials and active pharmaceutical ingredients, will be a major step forward. One such materials monomer targeted was enantioselective production of mandelic acid, a monomer for degradable thermoplastics with polystyrene-like properties ( 59 ) that can also serve in its enantiopure form as a building block for the synthesis of pharmaceuticals ( 60 ), with rapid scale-up delivery of g/l quantities in bioreactor cultures achieved.…”