Metabolic engineering of Escherichia coli for the production of isoflavonoid‐4′‐O‐methoxides and their biological activities

Abstract

Isoflavonoid representatives such as genistein, daidzein are high potent anti-cancer, anti-bacterial, anti-oxidant agents. It have been demonstrated that methylation of flavonoids enhanced the transporting ability, which lead to facilitated absorption and greatly increased bioavailability. In this paper, genetically engineered Escherichia coli was reconstructed by harboring E. coli K12-derived metK encoding S-adenosylmethionine (SAM) synthase (accession number: K02129) for enhancement of SAM as precursor and a Streptomyces avermitilis-originated SaOMT2 (O-methyltransferase, accession number: NP_823558) for methylation of daidzein and genistein as preferred substrates. The formation of desired products via biotransformation including 7-O-methyl-genistein and 7-O-methyl-daidzein were confirmed individually by chromatographical data such as HPLC, LC-TOF-MS and NMR ( H and C) as well. Furthermore, substrates concentration, incubation time and media parameters were optimized using flask culture. Finally, the most fit conditions were applied for fed-batch fermentation with scale up to 3 L (working volume) to obtain the maximum yield of the products including 164.25 μM (46.81 mg/L) and 382.50 μM (102.88 mg/L) for 7-O-methyl genistein and 7-O-methyl daidzein, respectively. In particular, potent inhibitory activities of those isoflavonoid methoxides against the growth of cancer line (B16F10, AGS and HepG2) and endothelical (HUVEC) cells were investigated and demonstrated. Taken together this research work described the production of isoflavonoid-7-O-methoxides by E. coli engineering, improvement of production, characterization of produced compounds and preliminary in vitro biological activities of the these flavonoids being manufactured. This article is protected by copyright. All rights reserved.

Bioactivity evaluations of leaf extract fractions from young barley grass and correlation with their phytochemical profiles

“…Phenolic compounds are a group of chemical compounds that are widely distributed in nature. Phenolic compounds are nutritionally important and the interest in these compounds are increasing for their various bioactivities such as antioxidant, anti-aging, antiinflammatory and anti-proliferative activities [25]. We found methanol to be significantly more efficient to extract polyphenolic compounds compared to ethyl acetate and hexane extracts of BG.…”

Enhancing the Pharmaceutical Properties of Flavonoids via Methylation and Glycosylation

“…Firstly we hypothesized that the methylation of these flavonoids will significantly increase their metabolic stability and biological activities, and then secondly, theirs subsequently glycosylated products will have enhanced solubility and better drug transport capability, making it more significant for formulation of pharmaceutical applications. Experimentally our hypothesis has been successfully implemented in the lab conditions [24][25][26].…”

Biochemical Characterization of a Flavonoid O-methyltransferase from Perilla Leaves and Its Application in 7-Methoxyflavonoid Production

“…FOMTs have potential applications in the biotechnological production of methoxyflavonoids [ 5 , 20 , 34 , 35 , 36 ]. In the present study, E. coli was engineered to harbor the PfOMT3 gene and then used to produce 7-methoxyflavonoids from flavonoids.…”

“…Thus, genetically engineered microorganisms transformed with biosynthetic genes, including FOMT s, have been used for the biotechnological production of valuable secondary metabolites [ 5 , 15 , 16 , 17 ]. The bioconversion yields of flavonoids to methoxyflavonoids using engineered microorganisms differ according to the FOMTs and substrates used, substrate concentrations, and culture conditions [ 5 , 22 , 34 , 35 , 36 ]. E. coli containing SlOMT3 efficiently converted luteolin and eriodictyol to chrysoeriol and homoeriodictyol, respectively, with more than 90% yields at a substrate concentration of 50 μM [ 20 ].…”