Iron is an essential but poorly bioavailable nutrient because of its low solubility, especially in alkaline soils. Here, we describe the discovery of a previously undescribed redox-active catecholic metabolite, termed sideretin, which derives from the couma- rin fraxetin and is the primary molecule exuded by Arabidopsis thaliana roots in response to iron deficiency. We identified two enzymes that complete the biosynthetic pathway of fraxetin and sideretin. Chemical characterization of fraxetin and sideretin, and biological assays with pathway mutants, suggest that these coumarins are critical for iron nutrition in A. thaliana. Further, we show that sideretin production also occurs in eudicot species only distantly related to A. thaliana. Untargeted metabolo- mics of the root exudates of various eudicots revealed production of structurally diverse redox-active molecules in response to iron deficiency. Our results indicate that secretion of small-molecule reductants by roots may be a widespread and previously underappreciated component of reduction-based iron uptake.
Biosynthesis of redox-active metabolites in response to iron deficiency in plants / J. Rajniak, R.F.H. Giehl, E. Chang, I. Murgia, N. von Wirén, E.S. Sattely. - In: NATURE CHEMICAL BIOLOGY. - ISSN 1552-4450. - 14:5(2018 May), pp. 442-450.
|Titolo:||Biosynthesis of redox-active metabolites in response to iron deficiency in plants|
|Parole Chiave:||Fe deficiency; P450; coumarins; fraxetin; sideretin; Arabidopsis; CYP82C4|
|Settore Scientifico Disciplinare:||Settore BIO/10 - Biochimica;|
Settore BIO/04 - Fisiologia Vegetale
Settore BIO/03 - Botanica Ambientale e Applicata
|Data di pubblicazione:||mag-2018|
|Data ahead of print / Data di stampa:||26-mar-2018|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1038/s41589-018-0019-2|
|Appare nelle tipologie:||01 - Articolo su periodico|