Richard A. Dixon

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Recognition of an avirulent pathogen stimulates an oxidative burst generating O2- and H2O2, and these reactive oxygen intermediates (ROIs) cue the induction of defense genes and cell death in the development of a restricted lesion. This localized hypersensitive response (HR) is accompanied by the development of systemic acquired resistance to virulent(More)
Localized attack by a necrotizing pathogen induces systemic acquired resistance (SAR) to subsequent attack by a broad range of normally virulent pathogens. Salicylic acid accumulation is required for activation of local defenses, such as pathogenesis-related protein accumulation, at the initial site of attack, and for subsequent expression of SAR upon(More)
Legumes (Fabaceae or Leguminosae) are unique among cultivated plants for their ability to carry out endosymbiotic nitrogen fixation with rhizobial bacteria, a process that takes place in a specialized structure known as the nodule. Legumes belong to one of the two main groups of eurosids, the Fabidae, which includes most species capable of endosymbiotic(More)
Recalcitrance to saccharification is a major limitation for conversion of lignocellulosic biomass to ethanol. In stems of transgenic alfalfa lines independently downregulated in each of six lignin biosynthetic enzymes, recalcitrance to both acid pretreatment and enzymatic digestion is directly proportional to lignin content. Some transgenics yield nearly(More)
Condensed tannins (CTs) are flavonoid oligomers, many of which have beneficial effects on animal and human health. The flavanol (-)-epicatechin is a component of many CTs and contributes to flavor and astringency in tea and wine. We show that the BANYULS (BAN) genes from Arabidopsis thaliana and Medicago truncatula encode anthocyanidin reductase, which(More)
Metabolomics or the large-scale phytochemical analysis of plants is reviewed in relation to functional genomics and systems biology. A historical account of the introduction and evolution of metabolite profiling into today's modern comprehensive metabolomics approach is provided. Many of the technologies used in metabolomics, including optical spectroscopy,(More)
Summary The functions of phenylpropanoid compounds in plant defence range from preformed or inducible physical and chemical barriers against infection to signal molecules involved in local and systemic signalling for defence gene induction. Defensive functions are not restricted to a particular class of phenylpropanoid compound, but are found in the simple(More)
Lignin is an aromatic heteropolymer and the second most abundant plant biopolymer after cellulose. It is deposited mostly in the secondary cell walls of vascular plants and is essential for water transport, mechanical support and for plant pathogen defense. Lignin biosynthesis is a highly energy-consuming and irreversible process that responds to many(More)
Proanthocyanidins are oligomeric and polymeric end products of the flavonoid biosynthetic pathway. They are present in the fruits, bark, leaves and seeds of many plants, where they provide protection against predation. At the same time they give flavor and astringency to beverages such as wine, fruit juices and teas, and are increasingly recognized as(More)
Metabolic channeling has been proposed to occur at the entry point into plant phenylpropanoid biosynthesis. To determine whether isoforms of L-Phe ammonia-lyase (PAL), the first enzyme in the pathway, can associate with the next enzyme, the endomembrane-bound cinnamate 4-hydroxylase (C4H), to facilitate channeling, we generated transgenic tobacco (Nicotiana(More)