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Engineering plants with increased levels of the antioxidant chlorogenic acid


The trend to view many foods not only as sustenance but also as medicine, so-called functional foods, is increasing. Phenolics are the most widespread dietary antioxidants, and among these, chlorogenic acid (CGA) accumulates to high levels in some crop plants. CGA acts as an antioxidant in plants and protects against degenerative, age-related diseases in animals when supplied in their diet. cDNA clones encoding the enzyme that synthesizes CGA, hydroxycinnamoyl-CoA quinate: hydroxycinnamoyl transferase (HQT), were characterized from tomato and tobacco. Gene silencing proved HQT to be the principal route for accumulation of CGA in solanaceous species. Overexpression of HQT in tomato caused plants to accumulate higher levels of CGA, with no side-effects on the levels of other soluble phenolics, and to show improved antioxidant capacity and resistance to infection by a bacterial pathogen. Tomatoes with elevated CGA levels could be used in foods with specific benefits for human health.

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Figure 1: Proposed pathways for the synthesis of chlorogenic acid in plants.
Figure 2: Analysis of the predicted HQT amino acid sequences and HQT gene expression.
Figure 3: Activity of recombinant HQT expressed in E. coli.
Figure 4: Modulation of HQT activity by transient transformation of N. benthamiana.
Figure 5: Correlation of increased HQT expression and gene silencing of HQT with the changes in HQT enzyme activity and content of CGA in transgenic tomato lines.
Figure 6: Increased levels of CGA result in better protection against oxidative stress and bacterial infection.

Accession codes




  1. 1

    Ness, A.R. & Powles, J.W. Fruit and vegetables and cardiovascular disease: A review. Int. J. Epidemiol. 26, 1–13 (1997).

    CAS  Article  Google Scholar 

  2. 2

    Segasothy, M. & Phillips P.A. Vegetarian diet: panacea for modern lifestyle diseases? Q.J. Med. 92, 531–544 (1999).

    CAS  Article  Google Scholar 

  3. 3

    Bazzano, L.A. et al. Fruit and vegetable intake and risk of cardiovascular disease in US adults, the first National Health and Nutrition Examination Survey Epidemiologic Follow-up Study. Am. J. Clin. Nutr. 76, 93–99 (2002).

    CAS  Article  Google Scholar 

  4. 4

    Laranjinha, J.A.N., Almeida, L.M. & Madeira, V.M. Reactivity of dietary phenolic acids with peroxyl radicals: antioxidant activity upon low density lipoprotein peroxidation. Biochem. Pharmacol. 48, 487–494 (1994).

    CAS  Article  Google Scholar 

  5. 5

    Sawa, T., Nakao, M., Akaike, T., Ono, K. & Maeda, H. Alkylperoxyl radical-scavenging activity of various flavonoids and other phenolic compounds: Implications for the anti-tumor-promoter effect of vegetables. J. Agric. Food Chem. 47, 397–402 (1999).

    CAS  Article  Google Scholar 

  6. 6

    Plumb, G.W. et al. Metabolism of chlorogenic acid by human plasma, liver, intestine and gut microflora. J. Sci. Food Agric. 79, 390–392 (1999).

    CAS  Article  Google Scholar 

  7. 7

    Williamson, G., Day, A.J., Plumb, G.W. & Couteau, D. Human metabolic pathways of dietary flavonoids and hydroxycinnamates. Biochem. Soc. Trans. 28, 16–22 (2000).

    CAS  Article  Google Scholar 

  8. 8

    Nardini, M., Cirillo, E., Natella, F. & Scaccini, C. Absorption of phenolic acids in humans after coffee consumption. J. Agric. Food Chem. 50, 5735–5741 (2002).

    CAS  Article  Google Scholar 

  9. 9

    Couteau, D., McCartney, A.L., Gibson, G.R., Williamson, G. & Faulds, C.B. Isolation and characterisation of human colonic bacteria able to hydrolyse chlorogenic acid. J. Applied Microbiol. 90 873–881 (2001).

    CAS  Article  Google Scholar 

  10. 10

    Scalbert, A., Morand, C., Manach, C. & Rémésy, C. Absorption and metabolism of polyphenols in the gut and impact on health. Biomed. Pharmacother. 56, 276–282 (2002).

    CAS  Article  Google Scholar 

  11. 11

    Rice-Evans, C.A., Miller, J. & Paganga, G. Antioxidant properties of phenolic compounds. Trends Plant Sci. 2, 152–159 (1997).

    Article  Google Scholar 

  12. 12

    Daniels, D.G.H., King, H.G.C. & Martin, H.F. Antioxidants in oats: Esters of phenolic acids. J. Sci. Food Agric. 14, 385–390 (1963).

    CAS  Article  Google Scholar 

  13. 13

    Daniels, D.G.H, & Martin, H.F. Antioxidants in oats: Mono-esters of caffeic and ferulic acids. J. Sci. Food Agric. 18, 589–595 (1967).

    CAS  Article  Google Scholar 

  14. 14

    Leatham, G.F., King, V. & Stahmann, M.A. In vitro protein polymerization by quinones or free-radicals generated by plant or fungal oxidative-enzymes. Phytopath. 70, 1134–1140 (1980).

    CAS  Article  Google Scholar 

  15. 15

    Tamagnone, L. et al. Inhibition of phenolic acid metabolism results in precocious cell death and altered cell morphology–in leaves of transgenic tobacco plants. Plant Cell 10, 1801–1816 (1998).

    CAS  Article  Google Scholar 

  16. 16

    Stöckigt, J. & Zenk, M.H. Enzymatic synthesis of chlorogenic acid from caffeoyl coenzyme A and quinic acid. FEBS Lett. 42, 131–134 (1974).

    Article  Google Scholar 

  17. 17

    Ulbrich, B. & Zenk, M.H. Partial purification and properties of hydroxycinnamoyl-CoA: quinate hydroxycinnamoyl transferase from higher plants. Phytochem. 18, 929–933 (1979).

    CAS  Article  Google Scholar 

  18. 18

    Rhodes, M.J.C. & Wooltorton, L.S.C. The enzymatic conversion of hydroxycinnamic acids to p-coumaroyl quinic and chlorogenic acids in tomato. Phytochem. 15, 947–951 (1976).

    CAS  Article  Google Scholar 

  19. 19

    Villegas, R.J.A. & Kojima, M. Purification and characterisation of hydroxycinnamoyl d-glucose quinate hydroxycinnamoyl transferase in the root of sweet potato, Ipomoea batatas LAM. J. Biol. Chem. 261, 8729–8733 (1986).

    CAS  PubMed  Google Scholar 

  20. 20

    Schoch, G. et al. CYP98A3 from Arabidopsis thaliana is a 3′ hydroxylase of phenolic esters, a missing link in the phenylpropanoid pathway. J. Biol. Chem. 276, 36566–36574 (2001).

    CAS  Article  Google Scholar 

  21. 21

    Franke, R. et al. The Arabidopsis REF8 gene encodes the 3-hydroxylase of phenylpropanoid metabolism. Plant J. 30, 33–45 (2002).

    CAS  Article  Google Scholar 

  22. 22

    Hoffmann, L., Maury, S., Martz, F., Geoffroy, P. & Legrand, M. Purification, cloning, and properties of an acyltransferase controlling shikimate and quinate ester intermediates in phenylpropanoid metabolism. J. Biol. Chem. 278, 95–103 (2003).

    CAS  Article  Google Scholar 

  23. 23

    Strack, D. & Gross, W. Properties and activity changes of chlorogenic acid glucaric acid caffeoyltransferase from tomato (Lycopersicon esculentum). Plant Physiol. 92, 41–47 (1990)

    CAS  Article  Google Scholar 

  24. 24

    Brown, N.F., Anderson, R.C., Caplan, S.L., Foster, D.W. & McGarry, J.D. Catalytically important domains of rat carnitine palmitoyltransferase-II as determined by site-directed mutagenesis and chemical modification - evidence for a critical histidine residue. J. Biol. Chem. 269, 19157–19162 (1994).

    CAS  PubMed  Google Scholar 

  25. 25

    St.-Pierre, B., Laflamme, P., Alarco, A.M. & De Luca, V . The terminal O-acetyltransferase involved in vindoline biosynthesis defines a new class of proteins responsible for coenzyme A-dependent acyl transfer. Plant J. 14, 703–713 (1998).

    CAS  Article  Google Scholar 

  26. 26

    Suzuki, H., Nakayoma, T. & Nishino, T. Proposed mechanism and functional amino acid residues of malonyl-CoA:anthocyanin5 -O-glucoside-6''' -O-malonyltransferase from flowers of Salvia splendens, a member of the versatile plant acyltransferase family. Biochemistry 42, 1764–1771 (2003).

    CAS  Article  Google Scholar 

  27. 27

    Friedman, M. Potato polyphenols: role in the plant and in the diet. ACS Symposium Series 662, 61–93 (1997).

    CAS  Article  Google Scholar 

  28. 28

    Edwards, A. et al. Specificity of starch synthase isoforms from potato. Eur. J. Biochem. 266, 724–736 (1999).

    CAS  Article  Google Scholar 

  29. 29

    Lofty, S., Fleuriet, A. & Macheix, J.J. Partial purification and characterisation of hydroxycinnamoyl CoA: transferases from apple and date fruits. Biochemistry 31, 767–772 (1992).

    Google Scholar 

  30. 30

    Voinnet, O., Rivas, S., Mestre, P. & Baulcombe, D. An enhanced transient expression system in plants based on suppression of gene silencing by the p19 protein of tomato bushy stunt virus. Plant J. 33, 949–956 (2003).

    CAS  Article  Google Scholar 

  31. 31

    Baker, N.R., Oxborough, K., Lawson, T. & Morrison, J.I.L. High resolution imaging of photosynthetic activities of tissues, cells and chloroplasts in leaves. J. Exp. Bot. 52, 615–621 (2001).

    CAS  Article  Google Scholar 

  32. 32

    Fryer, M.J., Oxborough, K., Mullineaux, P.M. & Baker, N.R. Imaging of photo-oxidative stress responses in leaves. J. Exp. Bot. 53, 1249–1254 (2002).

    CAS  PubMed  Google Scholar 

  33. 33

    Shedle, G.L. et al. Phenylpropanoid compounds and disease resistance in transgenic tobacco with altered expression of l-phenylalanine ammonia-lyase. Phytochem. 64, 153–161 (2003).

    Article  Google Scholar 

  34. 34

    Maher, E.A. et al. Increased disease susceptibility of transgenic tobacco plants with suppressed levels of preformed phenylpropanoid products. Proc. Natl. Acad. Sci. USA 91, 7802–7806 (1994).

    CAS  Article  Google Scholar 

  35. 35

    Howles, P.A. et al. Overexpression of l-phemylalanine ammonia lyase in transgenic tobacco plants reveals control points for flux into phenylpropanoid biosynthesis. Plant Physiol. 112, 1617–1624 (1996).

    CAS  Article  Google Scholar 

  36. 36

    Rober, K.C. Investigation on the synthesis of polyphenols and phytoalexins in rot infected potato-tubers. Biochem. Physiol. Pflanzen 184, 277–284 (1989).

    Article  Google Scholar 

  37. 37

    Perl-Treves, R. & Galun, E. The tomato Cu, Zn superoxide dismutase genes are developmentally regulated and respond to light and stress. Plant Mol. Biol. 17, 745–760 (1991).

    CAS  Article  Google Scholar 

  38. 38

    Tsang, E.W.T. et al. Differential regulation of superoxide dismutase in plants exposed to environmental stress. Plant Cell 3, 783–792 (1991).

    CAS  Article  Google Scholar 

  39. 39

    Broadbent, P., Creissen, G.P., Kular, B., Wellburn, A.R. & Mullineaux, P.M. Oxidative stress responses in transgenic tobacco containing altered levels of glutathione reductase activity. Plant J. 8, 247–255 (1995).

    CAS  Article  Google Scholar 

  40. 40

    Johnson, K.S. & Felton, G.W. Plant phenolics as dietary antioxidants for herbivorous insects: A test with genetically modified tobacco. J. Chem. Ecol. 27, 2579–2597 (2001).

    CAS  Article  Google Scholar 

  41. 41

    Tsuchiya, T., Suzuki, O. & Igarashi, K. Protective effects of chlorogenic acid on paraquat-induced oxidative stress in rats. Biosci. Biotech. Biochem. 60, 765–768 (1996).

    CAS  Article  Google Scholar 

  42. 42

    Speicher, K.D., Kolbas, O., Harper, S. & Speicher, D.W. Systematic analysis of peptide recoveries from in-gel digestions for protein identifications in proteome studies. J. Biomol. Tech. 11, 74–86 (2000).

    CAS  PubMed  PubMed Central  Google Scholar 

  43. 43

    Frohman, M.A., Dush, M.K. & Martin, G.R. Rapid production of full-length cDNAs from rare transcripts - amplification using a single gene-specific oligonucleotide primer. Proc. Natl. Acad. Sci. USA 85, 8998–9002 (1988).

    CAS  Article  Google Scholar 

  44. 44

    Semler, U., Schmidtberg, G. & Gross, G.G. Synthesis of a piperoyl coenzyme-A thioester. Z. Naturforsch. C. 42, 1070–1074 (1987).

    CAS  Article  Google Scholar 

  45. 45

    Waldron, K.W., Parr, A.J., Ng, A. & Ralph, J. Cell wall-esterified phenolic dimers: identification and quantification by reverse phase high performance liquid chromatography and diode array detection. Phytochem. Anal. 7, 305–312 (1996).

    CAS  Article  Google Scholar 

  46. 46

    Guerineau, F. & Mullineaux, P.M. Plant transformation and expression vectors. in Plant Molecular Biology Labfax (ed., Croy, R.R.D.) 121–147 (Bios Scientific Publishers, Oxford,–UK, 1993).

    Chapter  Google Scholar 

  47. 47

    Bevan, M. Agrobacterium vectors for plant transformation. Nucl. Acids Res. 12, 8711–8721 (1984).

    CAS  Article  Google Scholar 

  48. 48

    Fillatti, J.J., Kiser, J., Rose, R. & Comai, L. Efficient transfer of a glyphosate tolerance gene into tomato using a binary Agrobacterium-tumefaciens vector. Bio-technology 5, 726–730 (1987).

    CAS  Google Scholar 

  49. 49

    Mayer, M.J. et al. Rerouting the plant phenylpropanoid pathway by expression of a novel bacterial enoyl CoA hydratase/lyase enzyme function. Plant Cell 2, 1669–1682 (2001).

    Article  Google Scholar 

  50. 50

    Tamagnone, L. et al. The AmMYB308 and AmMYB330 transcription factors from Antirrhinum regulate phenylpropanoid metabolism and lignin biosynthesis in transgenic tobacco. Plant Cell 10, 13—154 (1998).

    Article  Google Scholar 

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We thank Alison Smith, Nick Walton and Adrian Parr for advice on enzyme purification and assay, Lionel Hill, Melinda Meyer and Fred Mellon for advice on HPLC and LC-MS, Mike Naldrett and Andrew Bottrill for provision of the Q-ToF-MS data, Phil Mullineaux and Baldeep Kumar for advice on measuring oxidative stress in plants, Max Dow for advice on pathogen infection of tomato, Mary Parker for lignin analysis, David Hopwood for comments on the manuscript, and Keith Waldron, Charlotte Parker, Stephen Bornemann and Andrew Smith for stimulating discussions on strategies to manipulate phenylpropanoid metabolism. This work was supported by award 218/D11645 from the Biological and Biotechnological Science Research Council (BBSRC) Agri-Food Committee, by the EU FP5 PROFOOD project (QLK1-CT-2001-01080) and both C.M. and A.J.M. are supported by core strategic grants from BBSRC.

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Correspondence to Cathie Martin.

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The authors have filed a patent application in the United Kingdom based on the technology described in this paper.

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Niggeweg, R., Michael, A. & Martin, C. Engineering plants with increased levels of the antioxidant chlorogenic acid. Nat Biotechnol 22, 746–754 (2004).

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