Metabolic Engineering of Isoflavonoid Biosynthesis by Expressing Glycine max Isoflavone Synthase in Allium cepa L. for Genistein Production

Isoflavonoids, the diverse group of secondary metabolites derived from the phenylpropanoid pathway, are distributed predominantly in leguminous plants and play a vital role in promoting human health. Genetic engineering of the metabolite synthesis pathway has turned out to be an attractive approach for the production of various secondary metabolites. In our study, we attempted to produce the isoflavone genistein, a well-known health-promoting metabolite, in Allium cepa L. (onion) by introducing Glycine max Isoflavone synthase (GmIFS). The GmIFS gene was cloned into the pEarleyGate 102 HA vector and transformed into onion by Agrobacterium-mediated and biolistic methods. The presence of GmIFS in transgenic onion was confirmed by PCR, dot blot, and Southern hybridization. Analysis of the transgenic onion calli lines demonstrated that the expression of the GmIFS gene led to the production of isoflavone genistein in in vitro tissues. The biolistic stable transformed calli with transformation efficiency of 73% (62.65 nM/g FW) accumulated more genistein than the Agrobacterium stable transformed calli with transformation efficiency of 56% (42.5 nM/g FW). Overall, heterologous gene expression of GmIFS was demonstrated by modifying the secondary metabolite pathway in onion tissues for the production of isoflavone genistein that can boost up human health with its health-promoting properties.

[1]  A. Hinchliffe,et al.  An efficient and reproducible Agrobacterium-mediated transformation method for hexaploid wheat (Triticum aestivum L.) , 2019, Plant Methods.

[2]  W. Gordon-Kamm,et al.  High efficiency Agrobacterium‐mediated site‐specific gene integration in maize utilizing the FLP‐FRT recombination system , 2019, Plant biotechnology journal.

[3]  A. Bakhsh,et al.  Transformation Efficiency of Five Agrobacterium Strains in Diploid and Tetraploid Potatoes , 2019, Sarhad Journal of Agriculture.

[4]  S. Ramalingam,et al.  Health Perspectives of an Isoflavonoid Genistein and its Quantification in Economically Important Plants , 2018 .

[5]  S. Ramalingam,et al.  Micropropagation and DNA delivery studies in onion cultivars of Bellary, CO3 , 2015, Journal of Crop Science and Biotechnology.

[6]  J. Milner,et al.  Garlic and Onions: Their Cancer Prevention Properties , 2015, Cancer Prevention Research.

[7]  H. Suleria,et al.  Onion: Nature Protection Against Physiological Threats , 2015, Critical reviews in food science and nutrition.

[8]  N. Gupta Onion ( Allium cepa ) – Ethnomedicinal and therapeutic properties , 2014 .

[9]  H. Pan,et al.  Metabolic engineering of isoflavone genistein in Brassica napus with soybean isoflavone synthase , 2011, Plant Cell Reports.

[10]  Mingfu Wang,et al.  Accumulation of isoflavone genistin in transgenic tomato plants overexpressing a soybean isoflavone synthase gene. , 2008, Journal of agricultural and food chemistry.

[11]  Yuanlei Hu,et al.  Production of soybean isoflavone genistein in non-legume plants via genetically modified secondary metabolism pathway. , 2007, Metabolic engineering.

[12]  X. Ye,et al.  Factors influencing Agrobacterium-mediated transformation of monocotyledonous species , 2007, In Vitro Cellular & Developmental Biology - Plant.

[13]  J. Ladha,et al.  Metabolic engineering of rice with soybean isoflavone synthase for promoting nodulation gene expression in rhizobia. , 2006, Journal of experimental botany.

[14]  F. Branca,et al.  Health effects of phytoestrogens. , 2005, Forum of nutrition.

[15]  I. Niopas,et al.  Validated high-performance liquid chromatographic method utilizing solid-phase extraction for the simultaneous determination of naringenin and hesperetin in human plasma. , 2004, Journal of chromatography. B, Analytical technologies in the biomedical and life sciences.

[16]  M. Chan,et al.  An efficient protocol for sugarcane (Saccharum spp. L.) transformation mediated by Agrobacterium tumefaciens , 1998, Transgenic Research.

[17]  K. Toriyama,et al.  Transgenic plant production mediated by Agrobacterium in Indica rice , 1996, Plant Cell Reports.

[18]  S. Gelvin,et al.  Factors influencing Agrobacterium-mediated transient expression of gusA in rice , 1992, Plant Molecular Biology.

[19]  B. Ford-Lloyd,et al.  The effects of acetosyringone and pH on Agrobacterium-mediated transformation vary according to plant species , 1991, Plant Cell Reports.

[20]  P. Hooykaas Transformation of plant cells via Agrobacterium , 1989, Plant Molecular Biology.

[21]  R. Dixon,et al.  Bottlenecks for metabolic engineering of isoflavone glycoconjugates in Arabidopsis , 2002, Proceedings of the National Academy of Sciences of the United States of America.

[22]  O. Yu,et al.  Production of the isoflavones genistein and daidzein in non-legume dicot and monocot tissues. , 2000, Plant physiology.

[23]  F. Jung,et al.  Influence of the Onion as an Essential Ingredient of the Mediterranean Diet on Arterial Blood Pressure and Blood Fluidity , 2000, Arzneimittelforschung.

[24]  O. Yu,et al.  Identification and expression of isoflavone synthase, the key enzyme for biosynthesis of isoflavones in legumes , 2000, Nature Biotechnology.

[25]  S. Raina,et al.  Agrobacterium-mediated transformation of indica ricecultivars using binary and superbinary vectors , 1999 .

[26]  H. Steinbiß,et al.  Factors Influencing T-DNA Transfer into Wheat and Barley Cells by Agrobacterium Tumefaciens , 1998 .

[27]  T. L. Graham,et al.  Flavonoid and isoflavonoid distribution in developing soybean seedling tissues and in seed and root exudates. , 1991, Plant physiology.

[28]  H. Dewar,et al.  Controlled trial of the effect of cycloalliin on the fibrinolytic activity of venous blood. , 1977, Atherosclerosis.