Induced plant responses to pathogen attack

Welle, Roland; Schröder, G.; Schiltz, Emil; Grisebach, Hans; Schröder, Joachim

doi:10.1111/j.1432-1033.1991.tb15833.x

Cited by 120 publications

(64 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…2J). As suggested by earlier sequence comparisons [69], CHR belongs to the aldo-keto reductase superfamily [28], and thus is more closely related to carbohydrate reductases than to analogous ketoreductase domains of fatty-acid and polyketide synthases.…”

Section: Flavonoid Biosynthesismentioning

confidence: 99%

Structure and function of enzymes involved in the biosynthesis of phenylpropanoids

Ferrer

Austin

Stewart

et al. 2008

Plant Physiology and Biochemistry

700

413

View full text Add to dashboard Cite

As a major component of plant specialized metabolism, phenylpropanoid biosynthetic pathways provide anthocyanins for pigmentation, flavonoids such as flavones for protection against UV photodamage, various flavonoid and isoflavonoid inducers of Rhizobium nodulation genes, polymeric lignin for structural support and assorted antimicrobial phytoalexins. As constituents of plant-rich diets and an assortment of herbal medicinal agents, the phenylpropanoids exhibit measurable cancer chemopreventive, antimitotic, estrogenic, antimalarial, antioxidant and antiasthmatic activities. The health benefits of consuming red wine, which contains significant amounts of 3,4′,5-trihydroxystilbene (resveratrol) and other phenylpropanoids, highlight the increasing awareness in the medical community and the public at large as to the potential dietary importance of these plant derived compounds. As recently as a decade ago, little was known about the three-dimensional structure of the enzymes involved in these highly branched biosynthetic pathways. Ten years ago, we initiated X-ray crystallographic analyses of key enzymes of this pathway, complemented by biochemical and enzyme engineering studies. We first investigated chalcone synthase (CHS), the entry point of the flavonoid pathway, and its close relative stilbene synthase (STS). Work soon followed on the O-methyl transferases (OMTs) involved in modifications of chalcone, isoflavonoids and metabolic precursors of lignin. More recently, our groups and others have extended the range of phenylpropanoid pathway structural investigations to include the upstream enzymes responsible for the initial recruitment of phenylalanine and tyrosine, as well as a number of reductases, acyltransferases and ancillary tailoring enzymes of phenylpropanoid-derived metabolites. These structure-function studies collectively provide a comprehensive view of an important aspect of phenylpropanoid metabolism. More specifically, these atomic resolution insights into the architecture and mechanistic underpinnings of phenylpropanoid metabolizing enzymes contribute to our understanding of the emergence and ongoing evolution of specialized phenylpropanoid products, and underscore the molecular basis of metabolic biodiversity at the chemical level. Finally, the detailed knowledge of the structure, function and evolution of these enzymes of specialized metabolism provide a set of experimental templates for the enzyme and metabolic engineering of production platforms for diverse novel compounds with desirable dietary and medicinal properties.

show abstract

Section: Flavonoid Biosynthesismentioning

confidence: 99%

Structure and function of enzymes involved in the biosynthesis of phenylpropanoids

Ferrer

Austin

Stewart

et al. 2008

Plant Physiology and Biochemistry

700

413

View full text Add to dashboard Cite

show abstract

“…Total RNA of treated soybean cells was prepared according to Schröder et al (1979) and 15 µg per lane were blotted onto Biodyne-A membranes (Pall, Dreieich, Germany). Hybridization probes used were: 3 kbp soybean actin gene, bean (Phaseolus vulgaris) chalcone synthase 1 (CHS) cDNA (Ryder et al, 1984), soybean reductase co-acting with CHS (CHR) partial cDNA clone p1 (Welle et al, 1991), soybean flavonoid 6-hydroxylase (F6H) gene-specific cDNA fragment Latunde-Dada et al, 2001), soybean 3,9-dihydroxypterocarpane 6a-hydroxylase (D6aH) gene-specific probe generated by PCR from the cDNA , soybean Gmhsp-26A glutathione S-transferase (GST) cDNA (Czarnecka et al, 1988, kindly provided by R. Tenhaken, University of Kaiserslautern, Germany), and partial soybean lipoxygenase 4 (LOX4, corresponding to swissprot accession P38417) cDNA (J. Fliegmann, unpublished).…”

Section: Northern Blot Analysesmentioning

confidence: 99%

The Role of Octadecanoids and Functional Mimics in Soybean Defense Responses

Fliegmann

Schüler

Boland

et al. 2003

Biological Chemistry

View full text Add to dashboard Cite

Oxylipins of the jasmonate pathway and synthetic functional analogs have been analyzed for their elicitor-like activities in an assay based on the induced accumulation of glyceollins, the phytoalexins of soybean (Glycine max L.), in cell suspension cultures of this plant. Jasmonic acid (JA) and its methyl ester showed weak phytoalexin-inducing activity when compared to an early jasmonate biosynthetic precursor, 12-oxo-phytodienoic acid (OPDA), as well as to the bacterial phytotoxin coronatine and certain 6-substituted indanoyl-L-isoleucine methyl esters, which all were highly active. Interestingly, different octadecanoids and indanoyl conjugates induced the accumulation of transcripts of various defense-related genes to different degrees, indicating distinct induction competencies. Therefore, these signaling compounds and mimics were further analyzed for their effects on signal transduction elements, such as the transient enhancement of the cytosolic Ca 2 + concentration and MAP kinase activation, which are known to be initiated by a soybean pathogen-derived ␤-glucan elicitor. In contrast to the ␤-glucan elicitor, none of the other compounds tested triggered these early signaling elements. Moreover, endogenous levels of OPDA and JA in soybean cells were shown to be unaffected after treatment with ␤-glucans. Thus, OPDA and JA, which are functionally mimicked by coronatine and a variety of 6-substituted derivatives of indanoyl-L-isoleucine methyl ester, represent highly efficient signaling compounds of a lipid-based pathway not deployed in the ␤-glucan elicitor-initiated signal transduction.

show abstract

“…Total RNA was extracted by the acid guanidium thiocyanatephenol-chloroform method, and reverse-transcribed using Reverscript (Wako) and oligo dT primer according to the manufacturer's protocol. The obtained cDNA mixture was used as a template for the PCR reactions with degenerate oligonucleotide primers based on the conserved sequences of known PKRs (chalcone reductases) [4][5][6][7] ; S1ϭ5Ј- (Fig. 1).…”

Section: Methodsmentioning

confidence: 99%

“…[4][5][6][7] Although the buried nature of the CHS active-site precludes PKR from accessing the CHS-enzyme-bound polyketide intermediate, PKR is thought to reduce a carbonyl group of a linear polyketide intermediate (or a non-aromatized 1,3,5-cyclohexatrione intermediate) prior to formation of the aromatic ring system. 16,17) To further study the plant PKR enzymes, we carried out cloning of PKRs from a medicinal plant Aloe arborescens (Liliaceae) that produces considerable amount of the "reduced" polyketides including anthrones and anthraquinones.…”

mentioning

confidence: 99%

“…Within the plant AKRs, aldose reductase, 3) polyketide reductase (PKR) (chalcone reductase), [4][5][6][7] alkaloid reductase (codeinone reductase), 8) and several plant oxidoreductases of poorly defined function [9][10][11][12][13][14] constitute the unique AKR4 family. Crystal structures of the first AKR4 members, Hordeum vulgare aldose reductase (4C1) 15) and Medicago sativa PKR (chalcone reductase) (4A2) 16) have recently been reported.…”

mentioning

confidence: 99%

See 1 more Smart Citation