title: Enhancing pterin and para-aminobenzoate content is not sufficient to successfully biofortify potato tubers and Arabidopsis thaliana plants with folate.
abstract: Folates are important cofactors in one-carbon metabolism in all living organisms. Since only plants and micro- organisms are capable of biosynthesizing folates, humans depend entirely on their diet as a folate source. Given the low folate content of several staple crop products, folate deficiency affects regions all over the world. Folate biofortification of staple crops through enhancement of pterin and para-aminobenzoate levels, precursors of the folate biosynthesis pathway, was reported to be successful in tomato and rice. This study shows that the same strategy is not sufficient to enhance folate content in potato tubers and Arabidopsis thaliana plants and concludes that other steps in folate biosynthesis and/or metabolism need to be engineered to result in substantial folate accumulation. The findings provide a plausible explanation why, more than half a decade after the proof of concept in rice and tomato, successful folate biofortification of other food crops through enhancement of para-aminobenzoate and pterin content has not been reported thus far. A better understanding of the folate pathway is required in order to determine an engineering strategy that can be generalized to most staple crops.
authors: Laboratory of Functional Plant Biology, Department of Physiology, Ghent University, K.L. Ledeganckstraat 35, 9000 Gent, Belgium.
authors: Dieter
authors: D
authors: Blancquaert
authors: Sergei
authors: S
authors: Storozhenko
authors: Jeroen
authors: J
authors: Van Daele
authors: Christophe
authors: C
authors: Stove
authors: Richard G F
authors: RG
authors: Visser
authors: Willy
authors: W
authors: Lambert
authors: Dominique
authors: D
authors: Van Der Straeten
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D018076:DNA, Complementary / Q000235:genetics / Q000378:metabolism; D005492:Folic Acid / Q000378:metabolism*; D006136:GTP Cyclohydrolase / Q000235:genetics* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism; D011622:Pterins / Q000378:metabolism; D011198:Solanum tuberosum / Q000235:genetics* / Q000378:metabolism; D000637:Transaminases / Q000235:genetics* / Q000378:metabolism; D062366:para-Aminobenzoates / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D018076:DNA, Complementary; D010940:Plant Proteins; D011622:Pterins; D062366:para-Aminobenzoates; D005492:Folic Acid; D000637:Transaminases; C066599:aminodeoxychorismate synthase; D006136:GTP Cyclohydrolase
keywords: Arabidopsis thaliana; biofortification; folate; folic acid; metabolic engineering; para-aminobenzoate; potato; pterin; tuber.