Biosynthesis and engineering of kaempferol in Saccharomyces cerevisiae

Abstract

Background: Kaempferol is a flavonol with broad bioactivity of anti-oxidant, anti-cancer, anti-diabetic, anti-microbial, cardio-protective and anti-asthma. Microbial synthesis of kaempferol is a promising strategy because of the low content in primary plant source. Methods:In this study, the biosynthesis pathway of kaempferol was constructed in the budding yeast Saccharomyces cerevisiae to produce kaempferol de novo, and several biological measures were taken for high production.Results: Firstly, a high efficient flavonol synthases (FLS) from Populus deltoides was introduced into the biosynthetic pathway of kaempferol. Secondly, a S. cerevisiae recombinant was constructed for de novo synthesis of kaempferol, which generated about 6.97 mg/L kaempferol from glucose. To further promote kaempferol production, the acetyl-CoA biosynthetic pathway was overexpressed and p-coumarate was supplied as substrate, which improved kaempferol titer by about 23 and 120%, respectively. Finally, a fed-batch process was developed for better kaempferol fermentation performance, and the production reached 66.29 mg/L in 40 h. Conclusions:The titer of kaempferol in our engineered yeast is 2.5 times of the highest reported titer. Our study provides a possible strategy to produce kaempferol using microbial cell factory.

Kaempferol inhibits angiogenic ability by targeting VEGF receptor-2 and downregulating the PI3K/AKT, MEK and ERK pathways in VEGF-stimulated human umbilical vein endothelial cells

“…Notably, kaempferol is a flavonoid phytochemical, which exists in a variety of fruits and vegetables, including onions, kale, broccoli, apples, cherries, berries, tea and red wine (40,41). Kaempferol has multiple bioactivities, including antitumor effects, an antioxidant activity, and an anti-inflammatory function (17)(18)(19)(20). In addition, kaempferol has induced apoptotic and autophagic cell death and/or cell cycle arrest in various tumor cell lines, including colon, liver, gastric and bladder cancer cells (25,27,(42)(43)(44)(45)(46)(47).…”

“…Kaempferol is a flavonoid phytochemical found in fruits and vegetables and in some traditional Chinese medicines (TCM) (14)(15)(16). Kaempferol has been reported to exert biological activities such as anti-inflammatory (17,18), antioxidant (19,20), cardioprotective (19) and antitumor (21)(22)(23). Kaempferol has been demonstrated to provide chemopreventive effects on different tumor systems including tumor initiation, promotion, and progression (24,25).…”

Flavonoids and Pectins

“…For example, eriodictyol has been produced using l-tyrosine as a substrate in E. coli BL21(DE3) genetically modified by TAL, 4CL, CHS, CHI, F3H, and F3'H genes and the production can reach up to 107 mg/L by further introducing three other genes acs, accBC, and dtsR1 to enhance the availability of malonyl-CoA [103]. Kaempferol has been produced in a microbial cell factory by introducing a de novo biosynthetic pathway into S. cerevisiae, and the biosynthesis has been further improved by introducing two more pathways to enhance the generation of acetyl-CoA and malonyl-CoA [107]. Obviously, this strategy circumvents some inherent disadvantages of traditional plant extraction and chemical synthesis.…”

Characterization of two flavonol synthases with iron-independent flavanone 3-hydroxylase activity from Ornithogalum caudatum Jacq

“…[20], Litchi chinensis [21], Cyclamen purpurascens [22], among others. Because of their vital role in flavonol biosynthesis, FLS genes were introduced into varied microbes to construct engineered cells for green preparation of flavonols [23][24][25][26][27][28][29][30][31]. However, the actual output of target flavonols in these engineered strains is insufficient for industrial production.…”