Name: biosynthesis of a flavonol from a flavanone by establishing a one-pot bienzymatic cascade
Uploaded: 2019-08-14T12:30:00.000+00:00
Duration: 9 min 50 s
Description: Watch this Scientific Journal Video about Biosynthesis of a Flavonol from a Flavanone by Establishing a One-pot Bienzymatic Cascade at JoVE.com

This work was financially supported by Yangzhou University Specially-Appointed Professor Start-up Funds, Jiangsu Specially-Appointed Professor Start-up Funds, Six Talent Peaks Project in Jiangsu Province (Grant No. 2014-SWYY-016), and a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (Veterinary Medicine). We thank the Testing Center of Yangzhou University for HPLC and MS analyses of flavonoids.

<ol>
	<li>Falcone Ferreyra, M. L., Rius, S. P., Casati, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flavonoids:+biosynthesis,+biological+functions,+and+biotechnological+applications.">Flavonoids: biosynthesis, biological functions, and biotechnological applications.</a> Frontiers in Plant Science. 3, 222 (2012).</li><li>Fang, F., Tang, K., Huang, W. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Changes+of+flavonol+synthase+and+flavonol+contents+during+grape+berry+development.">Changes of flavonol synthase and flavonol contents during grape berry development.</a> European Food Research and Technology. 237 (4), 529-540 (2013).</li><li>Cui, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Anthocyanins+and+flavonols+are+responsible+for+purple+color+of+Lablab+purpureus+(L.)+sweet+pods.">Anthocyanins and flavonols are responsible for purple color of Lablab purpureus (L.) sweet pods.</a> Plant Physiology and Biochemistry. 103, 183-190 (2016).</li><li>Li, X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+new+class+of+flavonol-based+anti-prostate+cancer+agents:+Design,+synthesis,+and+evaluation+in+cell+models.">A new class of flavonol-based anti-prostate cancer agents: Design, synthesis, and evaluation in cell models.</a> Bioorganic &amp; Medicinal Chemistry Letters. 26 (17), 4241-4245 (2016).</li><li>Kim, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regulation+of+Wnt+signaling+activity+for+growth+suppression+induced+by+quercetin+in+4T1+murine+mammary+cancer+cells.">Regulation of Wnt signaling activity for growth suppression induced by quercetin in 4T1 murine mammary cancer cells.</a> International Journal of Oncology. 43 (4), 1319-1325 (2013).</li><li>Kimura, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antioxidant+activities+and+structural+characterization+of+flavonol+O-glycosides+from+seeds+of+Japanese+horse+chestnut+(Aesculus+turbinata+BLUME).">Antioxidant activities and structural characterization of flavonol O-glycosides from seeds of Japanese horse chestnut (Aesculus turbinata BLUME).</a> Food Chemistry. 228, 348-355 (2017).</li><li>Cassidy, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Higher+dietary+anthocyanin+and+flavonol+intakes+are+associated+with+anti-inflammatory+effects+in+a+population+of+US+adults.">Higher dietary anthocyanin and flavonol intakes are associated with anti-inflammatory effects in a population of US adults.</a> The American Journal of Clinical Nutrition. 102 (1), 172-181 (2015).</li><li>Chao, H. C., Tsai, P. F., Lee, S. C., Lin, Y. S., Wu, M. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+Myricetin-Containing+Ethanol+Solution+on+High-Fat+Diet+Induced+Obese+Rats.">Effects of Myricetin-Containing Ethanol Solution on High-Fat Diet Induced Obese Rats.</a> Journal of Food Science. 82 (8), 1947-1952 (2017).</li><li>Serban, M. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+Quercetin+on+Blood+Pressure:+A+Systematic+Review+and+Meta-Analysis+of+Randomized+Controlled+Trials.">Effects of Quercetin on Blood Pressure: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.</a> Journal of the American Heart Association. 5 (7), (2016).</li><li>Nakagawa, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Improvement+of+memory+recall+by+quercetin+in+rodent+contextual+fear+conditioning+and+human+early-stage+Alzheimer's+disease+patients.">Improvement of memory recall by quercetin in rodent contextual fear conditioning and human early-stage Alzheimer's disease patients.</a> Neuroreport. 27 (9), 671-676 (2016).</li><li>Muthukrishnan, S. D., Kaliyaperumal, A., Subramaniyan, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identification+and+determination+of+flavonoids,+carotenoids+and+chlorophyll+concentration+in+Cynodon+dactylon+(L.)+by+HPLC+analysis.">Identification and determination of flavonoids, carotenoids and chlorophyll concentration in Cynodon dactylon (L.) by HPLC analysis.</a> Natural Product Research. 29 (8), 785-790 (2015).</li><li>Agar, O. T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparative+Studies+on+Phenolic+Composition,+Antioxidant,+Wound+Healing+and+Cytotoxic+Activities+of+Selected+Achillea+L.+Species+Growing+in+Turkey.">Comparative Studies on Phenolic Composition, Antioxidant, Wound Healing and Cytotoxic Activities of Selected Achillea L. Species Growing in Turkey.</a> Molecules. 20 (10), 17976-18000 (2015).</li><li>Yang, R. Y., Lin, S., Kuo, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Content+and+distribution+of+flavonoids+among+91+edible+plant+species.">Content and distribution of flavonoids among 91 edible plant species.</a> Asia Pacific Journal of Clinical Nutrition. 17, 275-279 (2008).</li><li>Tang, L. J., Zhang, S. F., Yang, J. Z., Gao, W. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=New+Synthetic+Methods+of+Flavones.">New Synthetic Methods of Flavones.</a> Chinese Journal of Organic Chemistry. 24 (8), 882-889 (2004).</li><li>Lu, Y. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthesis+of+luteolin+and+kaempferol+(author's+transl).">Synthesis of luteolin and kaempferol (author's transl).</a> Yao Xue Xue Bao. 15 (8), 477-481 (1980).</li><li>Zhang, Z., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+and+Optimization+of+an+In+vitro+Multienzyme+Synthetic+System+for+Production+of+Kaempferol+from+Naringenin.">Development and Optimization of an In vitro Multienzyme Synthetic System for Production of Kaempferol from Naringenin.</a> Journal of Agricultural and Food Chemistry. 66 (31), 8272-8279 (2018).</li><li>Malla, S., Pandey, R. P., Kim, B. G., Sohng, J. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regiospecific+modifications+of+naringenin+for+astragalin+production+in+Escherichia+coli.">Regiospecific modifications of naringenin for astragalin production in Escherichia coli.</a> Biotechnology and Bioengineering. 110 (9), 2525-2535 (2013).</li><li>Zhu, S., Wu, J., Du, G., Zhou, J., Chen, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficient+synthesis+of+eriodictyol+from+L-tyrosine+in+Escherichia+coli.">Efficient synthesis of eriodictyol from L-tyrosine in Escherichia coli.</a> Applied and Environmental Microbiology. 80 (10), 3072-3080 (2014).</li><li>Trantas, E., Panopoulos, N., Ververidis, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Metabolic+engineering+of+the+complete+pathway+leading+to+heterologous+biosynthesis+of+various+flavonoids+and+stilbenoids+in+Saccharomyces+cerevisiae.">Metabolic engineering of the complete pathway leading to heterologous biosynthesis of various flavonoids and stilbenoids in Saccharomyces cerevisiae.</a> Metabolic Engineering. 11 (6), 355-366 (2009).</li><li>Miyahisa, I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Combinatorial+biosynthesis+of+flavones+and+flavonols+in+Escherichia+coli.">Combinatorial biosynthesis of flavones and flavonols in Escherichia coli.</a> Applied Microbiology and Biotechnology. 71 (1), 53-58 (2006).</li><li>Leonard, E., Yan, Y., Koffas, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+expression+of+a+P450+flavonoid+hydroxylase+for+the+biosynthesis+of+plant-specific+hydroxylated+flavonols+in+Escherichia+coli.">Functional expression of a P450 flavonoid hydroxylase for the biosynthesis of plant-specific hydroxylated flavonols in Escherichia coli.</a> Metabolic Engineering. 8 (2), 172-181 (2006).</li><li>Koopman, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=De+novo+production+of+the+flavonoid+naringenin+in+engineered+Saccharomyces+cerevisiae.">De novo production of the flavonoid naringenin in engineered Saccharomyces cerevisiae.</a> Microbial Cell Factories. 11, 155 (2012).</li><li>Winkel-Shirley, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flavonoid+biosynthesis.+A+colorful+model+for+genetics,+biochemistry,+cell+biology,+and+biotechnology.">Flavonoid biosynthesis. A colorful model for genetics, biochemistry, cell biology, and biotechnology.</a> Plant Physiology. 126 (2), 485-493 (2001).</li><li>Duan, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biosynthesis+and+engineering+of+kaempferol+in+Saccharomyces+cerevisiae.">Biosynthesis and engineering of kaempferol in Saccharomyces cerevisiae.</a> Microbial Cell Factories. 16 (1), 165 (2017).</li><li>Cheng, Q., Xiang, L., Izumikawa, M., Meluzzi, D., Moore, B. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Enzymatic+total+synthesis+of+enterocin+polyketides.">Enzymatic total synthesis of enterocin polyketides.</a> Nature Chemical Biology. 3 (9), 557-558 (2007).</li><li>Connolly, M. A., Clausen, P. A., Lazar, J. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preparation+of+RNA+from+plant+tissue+using+trizol.">Preparation of RNA from plant tissue using trizol.</a> Cold Spring Harbor Protocols. (1), (2006).</li><li>Sambrook, J., Russell, D. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Purification+of+RNA+from+cells+and+tissues+by+Acid+phenol-guanidinium+thiocyanate-chloroform+extraction.">Purification of RNA from cells and tissues by Acid phenol-guanidinium thiocyanate-chloroform extraction.</a> Cold Spring Harbor Protocols. (1), (2006).</li><li>Sambrook, J., Russell, D. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Construction+of+cDNA+Libraries+Stage+1:+Synthesis+of+First-strand+cDNA+Catalyzed+by+Reverse+Transcriptase.">Construction of cDNA Libraries Stage 1: Synthesis of First-strand cDNA Catalyzed by Reverse Transcriptase.</a> Cold Spring Harbor Protocols. (1), (2006).</li><li>Sambrook, J., Russell, D. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Directional+cloning+into+plasmid+vectors.">Directional cloning into plasmid vectors.</a> Cold Spring Harbor Protocols. (1), (2006).</li><li>Sambrook, J., Russell, D. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Expression+of+Cloned+Genes+in+E.+coli+Using+IPTG-inducible+Promoters.">Expression of Cloned Genes in E. coli Using IPTG-inducible Promoters.</a> Cold Spring Harbor Protocols. (1), (2006).</li><li>Sambrook, J., Russell, D. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Purification+of+Histidine-tagged+Proteins+by+Immobilized+Ni2++Absorption+Chromatography.">Purification of Histidine-tagged Proteins by Immobilized Ni2+ Absorption Chromatography.</a> Cold Spring Harbor Protocols. (1), (2006).</li><li>Halbwirth, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measuring+flavonoid+enzyme+activities+in+tissues+of+fruit+species.">Measuring flavonoid enzyme activities in tissues of fruit species.</a> Journal of Agricultural and Food Chemistry. 57 (11), 4983-4987 (2009).</li><li>Prescott, A. G., Stamford, N. P., Wheeler, G., Firmin, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+properties+of+a+recombinant+flavonol+synthase+from+Arabidopsis+thaliana.">In vitro properties of a recombinant flavonol synthase from Arabidopsis thaliana.</a> Phytochemistry. 60 (6), 589-593 (2002).</li></ol>

The authors declare that they have no competing financial interests.

Quite a number of studies are focused on the derivation of flavonols due to their potential application in health care and food industry. However, traditional plant extraction using organic solvents and chemical synthesis possess intrinsic disadvantages, which restrict their use in the production of flavonols. Here, we report a detailed method for producing a flavonol from a flavanone in one pot by establishing an in vitro bienzymatic cascade. The critical steps in this protocol are: 1) obtaining pure recombinant enzymes...

Flavonols are a major subclass of plant flavonoids and are involved in plant development and pigmentation1,2,3. More importantly, these compounds possess a wide range of health-beneficial activities, such as anti-cancer4,5, anti-oxidative6, anti-inflammatory7, antiobesity8, anti-hypertensive9, and memory recall properties10, leading to a large number of studies on these plant-derived secondary metabolites. Traditionally, these compounds are mainly derived from plant extraction using organic solvents. However, due to their very low contents in plants11,12,13, the production cost for most flavonols remains high, which imposes great restrictions on their application in healthcare and the food industry.
During the past decades, scientists have developed quite a number of methods to derive flavonoids14,15. However, chemical synthesis of these complicated molecules possesses a variety of intrinsic disadvantages16. It requires not only toxic reagents and extreme reaction conditions, but also many steps to produce a target flavonoid compound14,17. Moreover, another important challenge in this strategy is the chiral synthesis of active flavonoid molecules. Therefore, it is not an ideal strategy to produce flavonoids at a commercial scale via chemical synthesis16,17.
Recently, scientists have developed a promising alternative strategy to produce these complicated natural compounds by engineering microbes with a pathway for flavonoid biosynthesis18,19,20,21,22, which has been successfully deciphered in plants23. For example, Duan et al. introduced a biosynthetic pathway into the budding yeast Saccharomyces cerevisiae to produce kaempferol (KMF)24. Malla et al. produced astragalin, a glycosylated flavonol, by introducingflavanone 3-hydroxylase (f3h), flavonol synthase (fls1), and UDP-glucose:flavonoid 3-O-glucosyltransferase UGT78K1 genes into Escherichia coliBL21(DE3)17. Even though there are quite a few paradigms, not all genetically engineered microbes produce the products of interest due to the complexity of a cellular platform, the incompatibility between artificially synthesized genetic elements and hosts, the inhibitory effect of target products against host cells, and the instability of an engineered cellular system itself16.
Another promising alternative strategy for flavonoid production is to establish a multienzymatic cascade in vitro. Cheng et al. have reported that enterocin polyketides can be successfully synthesized by assembling a complete enzymatic pathway in one pot25. This cell-free synthetic strategy circumvents the restrictions of a microbial production factory and thus is feasible for producing some flavonoids in large quantity16.
Recently, we have successfully developed a bienzyme synthetic system to convert naringenin (NRN) into KMF in one pot16. Here, we describe this system in great details and the methods involved in analyzing the products. We also present two examples that use this system to produce KMF from NRN and quercetin (QRC) from eriodictyol (ERD). In addition, we discuss crucial steps of this method and future research directions in the biosynthesis of flavonoids.

<table><tbody><tr><td>2&amp;times; Pfu MasterMix</td><td>Beijing CoWin Biotech Co., Ltd</td><td>CW0717A</td><td>PCR amplification of genes with high fidelity</td></tr><tr><td>Agilent 1200 Series RRLC system with an Agilent 6460 Triple Quadrupole LC/MS system</td><td>Agilent Technologies, Inc</td><td>N/A</td><td>an equipment for analysis of flavonoids by HPLC/MS</td></tr><tr><td>Agilent MassHunter Workstation (version B.03.01)</td><td>Agilent Technologies, Inc</td><td>N/A</td><td>a software for collection of the data from the Agilent 1200 Series RRLC system with an Agilent 6460 Triple Quadrupole LC/MS system</td></tr><tr><td>dihydrokaempferol</td><td>Sigma-Aldrich Co. LLC</td><td>91216</td><td>intermediate product for producing kaempferol from naringenin</td></tr><tr><td>dihydroquercetin</td><td>Sichuan Provincial Standard Substance Center for Chinese Herbal Medicine</td><td>PCS0371</td><td>intermediate product for producing quercetin from eriodictyol</td></tr><tr><td>DNA Clean-up Kit</td><td>Beijing CoWin Biotech Co., Ltd</td><td>CW2301</td><td>purification of PCR-amplified or gel-purified DNA</td></tr><tr><td>eriodictyol</td><td>Shanghai Yuan Ye Biotechnology Co., Ltd.</td><td>B21160</td><td>substrate for producing quercetin</td></tr><tr><td>&lt;em&gt;Escherichia coli&lt;/em&gt; BL21(DE3)</td><td>Beijing CoWin Biotech Co., Ltd</td><td>CW0809</td><td>bacteria strain for expressing target genes</td></tr><tr><td>&lt;em&gt;Escherichia coli&lt;/em&gt; DH5&amp;alpha;</td><td>Beijing CoWin Biotech Co., Ltd</td><td>CW0808</td><td>bacteria strain for plasmid proliferation</td></tr><tr><td>FreeZone 1 Liter Benchtop Freeze-Dry System</td><td>Labconco Corporation</td><td>7740020</td><td>an equipment for freeze-drying of flavonoids dissolved in organic solvent</td></tr><tr><td>Gel Extraction Kit</td><td>Beijing CoWin Biotech Co., Ltd</td><td>CW2302</td><td>purification of a DNA band from an agarose gel</td></tr><tr><td>Gel Imaging System</td><td>Shanghai Tanon Science &amp;amp; Technology Co. Ltd.</td><td>Tanon-&lt;br/&gt; 2500</td><td>an equipment for visualization of DNA band on an agarose gel or flavonoid spot on a polyamide TLC plate</td></tr><tr><td>GenElute Plasmid Miniprep Kit</td><td>Sigma-Aldrich Co. LLC</td><td>PLN350-1KT</td><td>minipreparation of plasmids</td></tr><tr><td>kaempferol</td><td>Sigma-Aldrich Co. LLC</td><td>60010</td><td>final reaction product and standard substance</td></tr><tr><td>MassHunter Quanlitative Analysis (version B.01.04)</td><td>Agilent Technologies, Inc</td><td>N/A</td><td>a software for analysis of HPLC/LC/MS data</td></tr><tr><td>NanoDrop Microvolume UV-Vis Spectrophotometer</td><td>Thermo Fisher Scientific</td><td>ND-8000-GL</td><td>an equipment for determination of DNA/RNA concentration</td></tr><tr><td>naringenin</td><td>Sigma-Aldrich Co. LLC</td><td>N5893</td><td>substrate for producing kaempferol</td></tr><tr><td>Ni-IDA Agarose Resin</td><td>Beijing CoWin Biotech Co., Ltd</td><td>CW0010</td><td>purification of His-tagged fusion proteins</td></tr><tr><td>pET-32a(+)</td><td>Novagen</td><td>69015-3</td><td>plasmid for cloning and expressing target genes</td></tr><tr><td>plasmid sequencing</td><td>GENEWIZ Suzhou</td><td>N/A</td><td>sequencing of recombinant plasmids</td></tr><tr><td>primer synthesis</td><td>GENEWIZ Suzhou</td><td>N/A</td><td>synthesis of PCR primers</td></tr><tr><td>quercetin</td><td>Shanghai Aladdin Biochemical Technology Co.,Ltd.</td><td>Q111273</td><td>final reaction product and standard substance</td></tr><tr><td>SuperRT cDNA Synthesis Kit</td><td>Beijing CoWin Biotech Co., Ltd</td><td>CW0741</td><td>synthesis of the first strand of cDNA from total RNA</td></tr><tr><td>T4 DNA Ligase</td><td>Thermo Fisher Scientific</td><td>EL0016</td><td>ligation of an insert into a linearized vector DNA</td></tr><tr><td>Trizol</td><td>Thermo Fisher Scientific</td><td>15596018</td><td>isolation of total RNA</td></tr><tr><td>Vector NTI Advance</td><td>Thermo Fisher Scientific</td><td>12605099</td><td>a software for PCR primer design and DNA sequence analysis</td></tr><tr><td>Xcalibur v2.0.7</td><td>Thermo Fisher Scientific</td><td>N/A</td><td>a software for analysis of HPLC data</td></tr></tbody></table>

biosynthesis of a flavonol from a flavanone by establishing a one-pot bienzymatic cascade

Flavonols are a major subclass of flavonoids with a variety of biological and pharmacological activities. Here, we provide a method for the in vitro enzymatic synthesis of a flavonol. In this method, Atf3h and Atfls1, two key genes in the biosynthetic pathway of the flavonols, are cloned and overexpressed in Escherichia coli. The recombinant enzymes are purified via an affinity column and then a bienzymatic cascade is established in a specific synthetic buffer. Two flavonols are synthesized in this system as examples and determined by TLC and HPLC/LC/MS analyses. The method displays obvious advantages in the derivation of flavonols over other approaches. It is time- and labor-saving and highly cost-effective. The reaction is easy to be accurately controlled and thus scaled up for mass production. The target product can be purified easily due to the simple components in the system. However, this system is usually restricted to the production of a flavonol from a flavanone.

F3H and FLS1 are two important key enzymes in the conversion of a flavanone into a flavonol in plants as shown in Figure 1. To develop an in vitro biosynthetic system for producing a flavonol from a flavanone, Atf3h (GenBank accession no.NM_114983.3) and Atfls1 (GenBank accession no. NM_120951.3) genes were cloned from the seedlings of 4-week-old A. thaliana into a prokaryotic expression vector pET-32a(+). The recombinant plasmids w...

Watch this Scientific Journal Video about Biosynthesis of a Flavonol from a Flavanone by Establishing a One-pot Bienzymatic Cascade at JoVE.com

Biosynthesis of a Flavonol from a Flavanone by Establishing a One-pot Bienzymatic Cascade

The derivation of a flavonol is crucial for its application in healthcare and the food industry. Here, we provide a detailed protocol for the biosynthesis of a flavonol from a flavanone and discuss the crucial steps and its advantages over other approaches.

Flavonols are a major subclass of flavonoids with a variety of biological and pharmacological activities. Here, we provide a method for the in vitro ...

biosynthesis-flavonol-from-flavanone-establishing-one-pot-bienzymatic

Research

JoVE Journal

Biochemistry

9.3K Views.  Yangzhou University. Met behulp van dit protocol kunnen we gemakkelijk een flink aantal flavonolen uit flavanones in één pot produceren. Deze techniek is arbeids- en tijdbesparend, zeer kosteneffectief en gemakkelijk te controleren, dus het heeft een enorm industrialisatiepotentieel. Ja, deze methode kan inzicht geven in de economische productie van andere secundaire metabolieten, maar het moet een aantal wijzigingen wanneer toegepast op het.Hij krijgt meestal niets of zeer lage opbrengst. Mijn advies is...

Video: Biosynthesis of a Flavonol from a Flavanone by Establishing a One-pot Bienzymatic Cascade

Synthetic Methodology for Asymmetric Ferrocene Derived Bio-conjugate Systems via Solid Phase Resin-based Methodology

Early detection is a key to successful treatment of most diseases, and is particularly imperative for the diagnosis and treatment of many types of cancer. The most common techniques utilized are imaging modalities such as Magnetic Resonance Imaging (MRI), Positron Emission Topography (PET), and Computed Topography (CT) and are optimal for understanding the physical structure of the disease but can only be performed once every four to six weeks due to the use of imaging agents and overall cost. With this in mind, the development of &#8220;point of care&#8221; techniques, such as biosensors, which evaluate the stage of disease and/or efficacy of treatment in the clinician&#8217;s office and do so in a timely manner, would revolutionize treatment protocols.1 As a means to exploring ferrocene based biosensors for the detection of biologically relevant molecules2, methods were developed to produce ferrocene-biotin bio-conjugates described herein. This report will focus on a biotin-ferrocene-cysteine system that can be immobilized on a gold surface.

The synthesis of asymmetric species of ferrocene is challenging using solution techniques. This report focuses on the methods carried out to produce a ferrocene-biotin bioconjugate using facile and clean reactions accomplished via solid-phase synthesis. Incorporation of a thiolate moiety is shown to impart the ability for immobilization on gold surfaces.

Early detection is a key to successful treatment of most diseases, and is particularly imperative for the diagnosis and treatment of many types of cancer. ...

Chemistry

Highly Stereoselective Synthesis of 1,6-Ketoesters Mediated by Ionic Liquids: A Three-component Reaction Enabling Rapid Access to a New Class of Low Molecular Weight Gelators

In organic chemistry ionic liquids (ILs) have emerged as safe and recyclable reaction solvents. In the presence of a base ILs can be deprotonated to form catalytically active N-Heterocyclic Carbenes (NHCs). Here we have used ILs as precatalysts in the addition of &#945;,&#946;-unsaturated aldehydes to chalcones to form 1,6-ketoesters, incorporating an anti-diphenyl moiety in a highly stereoselective fashion. The reaction has a broad substrate scope and several functional groups and heteroaromatics can be integrated into the ketoester backbone in generally good yields with maintained stereoselectivity. The reaction protocol is robust and scalable. The starting materials are inexpensive and the products can be obtained after simple filtration, avoiding solvent-demanding chromatography. Furthermore, the IL can be recycled up to 5 times without any loss of reactivity. Moreover, the 1,6-ketoester end product is a potent gelator in several hydrocarbon based solvents. The method enables rapid access to and evaluation of a new class of low molecular weight gelators (LMWGs) from recyclable and inexpensive starting materials.

Ionic liquids (ILs) mediate fast, simple and cheap access to 1,6-ketoesters in high diastereoselectivities and good yields. The reaction protocol is robust and the 1,6-ketoesters can be obtained in gram scale after a simple filtration protocol. Moreover, the 1,6-ketoesters are potent gelators in hydrocarbon solvents.

In organic chemistry ionic liquids (ILs) have emerged as safe and recyclable reaction solvents. In the presence of a base ILs can be deprotonated to form ...

Enzymatic Cascade Reactions for the Synthesis of Chiral Amino Alcohols from L-lysine

Amino alcohols are versatile compounds with a wide range of applications. For instance, they have been used as chiral scaffolds in organic synthesis. Their synthesis by conventional organic chemistry often requires tedious multi-step synthesis processes, with difficult control of the stereochemical outcome. We present a protocol to enzymatically synthetize amino alcohols starting from the readily available L-lysine in 48 h. This protocol combines two chemical reactions that are very difficult to conduct by conventional organic synthesis. In the first step, the regio- and diastereoselective oxidation of an unactivated C-H bond of the lysine side-chain is catalyzed by a dioxygenase; a second regio- and diastereoselective oxidation catalyzed by a regiodivergent dioxygenase can lead to the formation of the 1,2-diols. In the last step, the carboxylic group of the alpha amino acid is cleaved by a pyridoxal-phosphate (PLP) decarboxylase (DC). This decarboxylative step only affects the alpha carbon of the amino acid, retaining the hydroxy-substituted stereogenic center in a beta/gamma position. The resulting amino alcohols are therefore optically enriched. The protocol was successfully applied to the semipreparative-scale synthesis of four amino alcohols. Monitoring of the reactions was conducted by high performance liquid chromatography (HPLC) after derivatization by 1-fluoro-2,4-dinitrobenzene. Straightforward purification by solid-phase extraction (SPE) afforded the amino alcohols with excellent yields (93% to &#62;95%).

Chiral amino alcohols are versatile molecules for use as scaffolds in organic synthesis. Starting from L-lysine, we synthesize amino alcohols by an enzymatic cascade reaction combining diastereoselective C-H oxidation catalyzed by dioxygenase followed by cleavage of the carboxylic acid moiety of the corresponding hydroxyl amino acid by a decarboxylase.

Amino alcohols are versatile compounds with a wide range of applications. For instance, they have been used as chiral scaffolds in organic synthesis. ...

A Customizable Approach for the Enzymatic Production and Purification of Diterpenoid Natural Products

Diterpenoids form a diverse class of small molecule natural products that are widely distributed across the kingdoms of life and have critical biological functions in developmental processes, interorganismal interactions, and environmental adaptation. Due to these various bioactivities, many diterpenoids are also of economic importance as pharmaceuticals, food additives, biofuels, and other bioproducts. Advanced genomics and biochemical approaches have enabled a rapid increase in the knowledge of diterpenoid-metabolic genes, enzymes, and pathways. However, the structural complexity of diterpenoids and the narrow taxonomic distribution of individual compounds in often only a single species remain constraining factors for their efficient production. Availability of a broader range of metabolic enzymes now provide resources for producing diterpenoids in sufficient titers and purity to facilitate a deeper investigation of this important metabolite group. Drawing on established tools for microbial and plant-based enzyme co-expression, we present an easily operated and customizable protocol for the enzymatic production of diterpenoids in either Escherichia coli or Nicotiana benthamiana, and the purification of desired products via silica chromatography and semi-preparative HPLC. Using the group of maize (Zea mays) dolabralexin diterpenoids as an example, we highlight how modular combinations of diterpene synthase (diTPS) and cytochrome P450 monooxygenase (P450) enzymes can be used to generate different diterpenoid scaffolds. Purified compounds can be used in various downstream applications, such as metabolite structural analyses, enzyme structure-function studies, and in vitro and in planta bioactivity experiments.

Here we present easy to use protocols for producing and purifying diterpenoid metabolites through the combinatorial expression of biosynthetic enzymes in Escherichia coli or Nicotiana benthamiana, followed by chromatographic product purification. The resulting metabolites are suitable for various studies including molecular structure characterization, enzyme functional studies, and bioactivity assays.

Diterpenoids form a diverse class of small molecule natural products that are widely distributed across the kingdoms of life and have critical biological ...

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species

&#945;-Functionalization of ketones via umpolung of enolates by hypervalent iodine reagents is an important concept in synthetic organic chemistry. Recently, we have developed a two-step strategy for ketone enolate umpolung that has enabled the development of methods for chlorination, azidation, and amination using azoles. In addition, we have developed C-C bond&#8211;forming arylation and allylation reactions. At the heart of these methods is the preparation of the intermediate and highly reactive enolonium species prior to addition of a reactive nucleophile. This strategy is thus reminiscent of the preparation and use of metal enolates in classical synthetic chemistry. This strategy allows the use of nucleophiles that would otherwise be incompatible with the strongly oxidizing hypervalent iodine reagents. In this paper we present a detailed protocol for chlorination, azidation, N-heteroarylation, arylation, and allylation. The products include motifs prevalent in medicinally active products. This article will greatly assist others in using these methods.

A two step one-pot protocol for the umpolung of ketone enolates to enolonium species and addition of a nucleophile to the &#945;-position is described. Nucleophiles include chloride, azide, azoles, allyl-silanes, and aromatic compounds.

&#945;-Functionalization of ketones via umpolung of enolates by hypervalent iodine reagents is an important concept in synthetic organic chemistry. ...

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of &#945;-Imino &#947;-Lactones and Alkylidene Pyrazolones

Bispirocyclic scaffolds are one of the important structural subunits in many natural products that exhibit diverse and attractive biological activities. Recently, we have developed an efficient organocatalytic strategy, which provides facile access to a variety of enantiomerically enriched bispiro[&#947;-butyrolactone-pyrrolidin-4,4&#39;-pyrazolone] skeletons. In this paper, we demonstrate a detailed protocol for the asymmetric synthesis of drug-like bispirocyclic compounds with two spirocyclic carbon centers via an organocatyltic 1,3-dipolar cycloaddition reaction. Spirocyclization synthons &#945;-imino &#947;-lactones and alkylidene pyrazolones are prepared first, which are then subjected to a cycloaddition reaction in the presence of a bifunctional squaramide organocatalyst to afford the desired bispirocycles in high yields and excellent stereoselectivities. Chiral high-performance liquid chromatography (HPLC) is carried out to determine the enantiomeric purity of the products, and the d.r. value is examined by proton nuclear magnetic resonance (1H NMR). The absolute configuration of the product is assigned according to an X-ray crystallographic analysis. This synthetic strategy allows scientists to prepare a diversity of bispirocyclic scaffolds in high yields and excellent diastereo- and enantioselectivities.

Enantiomerically enriched bispiro[&#947;-butyrolactone-pyrrolidin-4,4&#39;-pyrazolone] skeletons are asymmetrically synthesized through a simple organocatalytic 1,3-dipolar cycloaddition reaction.

Bispirocyclic scaffolds are one of the important structural subunits in many natural products that exhibit diverse and attractive biological activities. ...

Versatile CO2 Transformations into Complex Products: A One-pot Two-step Strategy

CO2 transformations using a one-pot two-step method are presented herein. The purpose of the method is to give access to a variety of value-added products and notably to generate chiral carbon centers. The crucial first step consists in the selective double hydroboration of CO2 catalyzed by an iron hydride complex. The product obtained with this 4 e- reduction is a rare bis(boryl)acetal, compound 1, which is subjected in situ to three different reactions in a second step. The first reaction concerns a condensation reaction with (diisopropyl)phenylamine affording the corresponding imine 2. In the second and third reaction, intermediate 1 reacts with triazol-5-ylidene (Enders&#39; carbene) to afford compounds 3 or 4, depending on the reaction conditions. In both compounds, C-C bonds are formed, and chiral centers are generated from CO2 as the only source of carbon. Compound 4 exhibits two chiral centers obtained in a diastereoselective manner in a formose-type mechanism. We proved that the remaining boryl fragment plays a key role in this unprecedented stereocontrol. The interest of the method stands on the reactive and versatile nature of 1, giving rise to various complex molecules from a single intermediate. The complexity of a two-step method is compensated by the overall short reaction time (2 h for the larger reaction time), and mild reaction conditions (25 &#176;C to 80 &#176;C and 1 to 3 atm of CO2).

Versatile CO2 Transformations into Complex Products: A One-pot Two-step Strategy

CO2 transformations are conducted in a one-pot two-step procedure for the synthesis of complex molecules. The selective 4 e- reduction of CO2 with a hydroborane reductant affords a reactive and versatile bis(boryl)acetal intermediate which is subsequently involved in condensation reaction or carbene-mediated C-C coupling generation.

CO2 transformations using a one-pot two-step method are presented herein. The purpose of the method is to give access to a variety of value-added products ...

Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions

The interest on nitrogen-containing heterocycles has expanded rapidly in the synthetic community since they are important motifs for new drugs. Traditionally, they were synthesized through thermal cycloaddition reactions, whereas today, photocatalysis is preferred due to the mild and efficient conditions. With this focus, a new photocatalytic method for the synthesis of nitrogen-containing heterocycles is highly desired. Here, we report a protocol for the biosynthesis of cercosporin, which could function as a metal-free photocatalyst. We then illustrate cercosporin-photocatalyzed protocols for the synthesis of nitrogen-containing heterocycles 1,2,3-thiadiazoles through annulation of azoalkenes with KSCN, and synthesis of 1,4,5,6-tetrahydropyridazines [4+2] through cyclodimerization of azoalkenes under mild conditions, respectively. As a result, there is a new bridge between the microbial fermentation method and organic synthesis in a mild, cost-effective, environmentally friendly and sustainable manner.

New routes for the synthesis of nitrogen-containing heterocycles utilizing cercosporin as a metal-free photocatalyst were developed.

The interest on nitrogen-containing heterocycles has expanded rapidly in the synthetic community since they are important motifs for new drugs. ...

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach

Methine-bridged conjugated bicyclic aromatic compounds are common constituents of a range of biologically relevant molecules such as porphyrins, dipyrrinones, and pharmaceuticals. Additionally, restricted rotation of these systems often results in highly to moderately fluorescent systems as observed in 3H,5H-dipyrrolo[1,2-c:2',1'-f]pyrimidin-3-ones, xanthoglows, pyrroloindolizinedione analogs, BODIPY analogs, and the phenolic and imidazolinone ring systems of Green Fluorescent Protein (GFP). This manuscript describes an inexpensive and operationally simple method of performing a Claisen-Schmidt condensation to generate a series of fluorescent pH dependent pyrazole/imidazole/isoindolone dipyrrinone analogs. While the methodology illustrates the synthesis of dipyrrinone analogs, it can be translated to produce a wide range of conjugated bicyclic aromatic compounds. The Claisen-Schmidt condensation reaction utilized in this method is limited in scope to nucleophiles and electrophiles that are enolizable under basic conditions (nucleophile component) and non-enolizable aldehydes (electrophile component). Additionally, both the nucleophilic and electrophilic reactants must contain functional groups that will not inadvertently react with hydroxide. Despite these limitations, this methodology offers access to completely novel systems that can be employed as biological or molecular probes.

The Claisen-Schmidt condensation reaction is an important methodology for the generation of methine-bridged conjugated bicyclic aromatic compounds. Through utilizing a base-mediated variant of the aldol reaction, a range of fluorescent and/or biologically relevant molecules can be accessed through a generally inexpensive and operationally simple synthetic approach.

Methine-bridged conjugated bicyclic aromatic compounds are common constituents of a range of biologically relevant molecules such as porphyrins, ...

Lignin Micro-/Submicron Particle Synthesis for Bioflavonoid Release

Green Synthesis, Characterization, Encapsulation, and Measurement of the Release Potential of Novel Alkali Lignin Micro-/Submicron Particles

The applicability of biopolymer micro-/nano- technology in human, veterinary medicine, pharmaceutical, and food technology is rapidly growing due to the great potential of biopolymer-based particles as effective carrier systems. The use of lignin as a basic heteropolymer biomatrix for the design of innovative micro-/submicron formulations allows the achievement of increased biocompatibility and offers various active functional groups presenting opportunities for customization of the physicochemical properties and bioactivities of the formulations for diverse applications. The aim of the present study was to develop a simple and ecofriendly methodology for the synthesis of lignin particles with micro- and submicron size; to evaluate their physicochemical, spectral, and structural characteristics; and to examine their capacity for encapsulation of biologically active molecules and potential for in vitro release of bioflavonoids in simulated gastrointestinal media. The presented methodologies apply cheap and green solvents; easy, straightforward, quick, and sensitive processes requiring little equipment, non-toxic substances, and simple methods for their characterization, the determination of encapsulation capacity towards the poorly water-soluble bioactive compounds morin and quercetin, and the in vitro release potential of the lignin matrices.

Author Spotlight: Development and Characterization of Eco-Friendly Lignin-Based Microparticles for Enhanced Delivery of Bioflavonoids

We describe novel, simple methodologies of synthesis and characterization of biocompatible lignin micro- and submicron particles. These formulations provide a facile approach for the utilization of the heteropolymer, as well as an alternative for the rational design of multifunctional carrier matrices with potential applicability in biomedicine, pharmaceutical technology, and the food industry.

The applicability of biopolymer micro-/nano- technology in human, veterinary medicine, pharmaceutical, and food technology is rapidly growing due to the ...

Biosynthesis of a Flavonol from a Flavanone by Establishing a One-pot Bienzymatic Cascade

Samenvatting

Meer video's verkennen

Hoofdstukken in deze video