Abstract
Flavonoids are abundant in the leaves, flowers, branches, bark, and heartwood of Acacia confusa Merr. (Leguminosae), and the extracts have been found to have strong antioxidant activities. Flavonols are the major class of flavonoids found in A. confusa. The full-length gene (designated as AcFLS) contains an open reading frame of 996 nucleotides encoding 331 amino acid residues with a predicted molecular weight of 38 kDa and pI of 5.7. AcFLS mRNAs were abundant in the seedlings leaves and the flowers. Wounding by cutting leaves induced maximum AcFLS mRNA accumulation 6-12 h after treatment. AcFLS could enzymatically transform dihydromyricetin, dihydroquercetin, and naringenin into the flavonols myricetin, quercetin, and kaempferol, respectively. AcFLS could bind these three substrates with similar affinity.
Similar content being viewed by others
References
Baker EN, Hubbard RE (1984) Hydrogen bonding in globular proteins. Prog Biophys Mol Biol 44:97–139
Bohm H, Boeing H, Hempel J, Raab B, Kroke A (1998) Flavonols, flavones and anthocyanins as native antioxidants of food and their possible role in the prevention of chronic diseases. Z Ernahrungswiss 37:147–163
Chua CS, Biermann D, Goo KS, Sim TS (2008) Elucidation of active site residues of Arabidopsis thaliana flavonol synthase provides a molecular platform for engineering flavonols. Phytochemistry 69:66–75
Ferreyra MLF, Rius S, Emiliani J, Pourcel L, Feller A, Morohashi K, Casati P, Grotewold E (2010) Cloning and characterization of a UV-B-inducible maize flavonol synthase. Plant J 62:77–91
Fujita A, Goto-Yamamoto N, Aramaki I, Hashizume K (2006) Organ-specific transcription of putative flavonol synthase genes of grapevine and effects of plant hormones and shading on flavonol biosynthesis in grape berry skins. Biosci Biotech Biochem 70:632–638
Grotewold E (2005) Plant metabolic diversity: a regulatory perspective. Trends Plant Sci 10:57–62
Harborne JB, Williams CA (2000) Advances in flavonoid research since 1992. Phytochemistry 55:481–504
Havsteen BH (2002) The biochemistry and medical significance of the flavonoids. Pharmacol Therapeut 96:67–202
Hegnauer R, Gpayer-Barkmeijer RJ (1993) Relevance of seed polysaccharides and flavonoids for the classification of the Leguminosae: a chemotaxonomic approach. Phytochemistry 34:3–16
Holton TA, Brugliera F, Lester DR, Tanaka Y, Hyland CD, Menting JGT, Lu CY, Farcy E, Stevenson TW, Cornish EC (1993) Cloning and expression of cytochrome P450 genes controlling flower colour. Nature 366:276–279
Hsieh CY, Chang ST (2010) Antioxidant activities and xanthine oxidase inhibitory effects of phenolic phytochemicals from Acacia confusa twigs and branches. J Agric Food Chem 58:1578–1583
Kim BG, Kim JH, Kim J, Lee C, Ahn JH (2008) Accumulation of flavonols in response to ultraviolet-B irradiation in soybean is related to induction of flavanone 3-beta-hydroxylase and flavonol synthase. Mol Cells 25:247–252
Lukačin R, Wellmann F, Britsch L, Martens S, Matern U (2003) Flavonol synthase from Citrus unshiu is a bifunctional dioxygenase. Phytochemistry 62:287–292
Mellway RD, Tran LT, Prouse MB, Campbell MM, Constabel CP (2009) The Wound-, pathogen-, and ultraviolet B-responsive MYB134 gene encodes an R2R3 MYB transcription factor that regulates proanthocyanidin synthesis in poplar. Plant Physiol 150:924–941
Owens DK, Alerding AB, Crosby KC, Bandara AB, Westwood JH, Winkel BSJ (2008) Functional analysis of a predicted flavonol synthase gene family in Arabidopsis. Plant Physiol 147:1046–1061
Prescott AG, John P (1996) Dioxygenases: molecular structure and role in plant metabolism. Annu Rev Plant Biol 47:245–271
Prescott AG, Stamford NPJ, Wheelera G, Firmina JL (2002) In vitro properties of a recombinant flavonol synthase from Arabidopsis thaliana. Phytochemistry 60:589–593
Ross JA, Kasum CM (2002) Dietary flavonoids: bioavailability, metabolic effects, and safety. Annu Rev Nutr 22:19–34
Schwede T, Kopp J, Guex N, Peitsch MC (2003) SWISS-MODEL: an automated protein homology-modeling server. Nucleic Acids Res 31:3381–3385
Takahashi R, Githiri SM, Hatayama K, Dubouzet EG, Shimada N, Aoki T, Ayabe S, Iwashina T, Toda K, Matsumura H (2007) A single-base deletion in soybean flavonol synthase gene is associated with magenta flower color. Plant Mol Biol 63:125–135
Tung YT, Wu JH, Huang CY, Kuo YH, Chang ST (2009) Antioxidant activities and phytochemical characteristics of extracts from Acacia confusa bark. Bioresour Technol 100:509–514
Wilmouth RC, Turnbull JJ, Welford RWD, Clifton IJ, Prescott AG, Schofield CJ (2002) Structure and mechanism of anthocyanidin synthase from Arabidopsis thaliana. Structure 10:93–103
Winkel-Shirley B (2001) Flavonoid biosynthesis: a colorful model for genetics, biochemistry, cell biology, and biotechnology. Plant Physiol 126:485–493
Wu JH, Tung YT, Wang SY, Shyur LF, Kuo YH, Chang ST (2005) Phenolic antioxidants from the heartwood of Acacia confusa. J Agric Food Chem 53:5917–5921
Wu JH, Huang CY, Tung YT, Chang ST (2008) Online RP-HPLC-DPPH screening method for detection of radical-scavenging phytochemicals from flowers of Acacia confusa. J Agric Food Chem 56:328–332
Yazaki K (2005) Transporters of secondary metabolites. Curr Opin Plant Biol 8:301–307
Acknowledgments
We thank the Council of Agriculture Executive Yuan of Taiwan for financial support.
Author information
Authors and Affiliations
Corresponding author
Additional information
Communicated by R. Sederoff
Rights and permissions
About this article
Cite this article
Toh, HC., Wang, SY., Chang, ST. et al. Molecular cloning and characterization of flavonol synthase in Acacia confusa . Tree Genetics & Genomes 9, 85–92 (2013). https://doi.org/10.1007/s11295-012-0536-1
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11295-012-0536-1