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Plant Cell Walls (plant + cell_wall)

Distribution by Scientific Domains

Life Sciences	65%
Chemistry	35%

Distribution within Life Sciences

Plant Science	38%
Biotechnology (Life Sciences)	15%

Selected Abstracts

Interrelation between Lignin Deposition and Polysaccharide Matrices during the Assembly of Plant Cell Walls

PLANT BIOLOGY, Issue 1 2002
K. Ruel
Abstract: The modifications caused by genetic down-regulation of the enzyme cinnamoyl CoA reductase (CCR) from monolignol biosynthetic pathways on tobacco and Arabidopsis thaliana were investigated at the ultrastructural level. A typical result was that the same transformation led to similar abnormality in secondary wall formation of fibres in both plants. The cell wall alterations mainly consisted in an important disorganization and loosening of cellulose microfibrils in the inner part of the S2 layer. This inability of the transformants to form a coherent cell wall coincided with a lack of synthesis of non-condensed forms of lignin in this disorganized region of the wall, as demonstrated by immunolabelling of lignin subunits. A similar disorganization was observed during fibre wall formation in the differentiating tissues of young Populus and A. thaliana plants. The transitory lack of organization of cellulose microfibrils, also coincided with a depletion in non-condensed forms of lignins. These results suggest that such lignin substructures may be involved in the cohesion of secondary walls during cell wall biogenesis. The mutual influence of the cellulose-hemicellulose environment and monolignol local polymerization is discussed. [source]

Indigestibility of plant cell wall by the Australian plague locust, Chortoicetes terminifera

ENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 3 2004
F.J. Clissold
Abstract The plant cell wall may play an important role in defence against herbivores since it can be both a barrier to, and nutrient diluter of, the easily digested cell contents. The aim of this study was to investigate the digestibility of the cell wall of three grasses, Triticum aestivum L., Dactyloctenium radulans (R. Br.) Beauv., and Astrebla lappacea (Lindl.) Domin, by the Australian plague locust, Chortoicetes terminifera Walker (Orthoptera: Acrididae, Acridinae) as determined by the Van Soest method [Van Soest PJ, Robertson JB & Lewis BA (1991) Methods for dietary fiber, neutral detergent fiber, and nonstarch polysaccharides in relation to animal nutrition. Journal of Dairy Science 74: 3583,3597]. Determination of plant cell wall digestion by locusts required a precise methodological procedure to determine both the exact intake and the concentration of cell wall in the diet and the faeces. Plant cell wall determination is affected by the particle size distribution of the dried plant material. All three grasses differed in the percentage of cell wall per gram dry matter and the proportions of hemicellulose, cellulose, and acid-detergent sulphuric lignin within the cell wall. The locust was unable to digest the cell wall of any of the grasses. Thus, plant cell walls are a mechanical barrier hindering locusts assimilating nutrients. That is, access, rather than nutrient concentration per se, may be limiting nutrient factor. [source]

Structural determination of the O-chain polysaccharide from Agrobacterium tumefaciens, strain DSM 30205

FEBS JOURNAL, Issue 12 2002
Cristina De Castro
Agrobacterium tumefaciens is a Gram-negative, phytopathogenic bacterium and is characterized by an unique mode of action on dicotyledonous plants: it is able to genetically modify the host, and because of this feature, it is used as a tool for transgenic plants. Many experiments have demonstrated that lipopolysaccharides (LPSs) play an important role for the disease development, as they are involved in the adhesion process of the bacterium on the plant cell wall. Despite the wealth of information on the role of LPS on phytopathogenesis, the present paper appears as the first report on the molecular primary structure of the O-chain produced from Agrobacterium. Its repeating unit was determined by means of chemical and spectroscopical analysis, and has the following structure: (3)-,- d -Araf -(1,3)-,- l -Fucp -(1,. [source]

Enzymatic deconstruction of xylan for biofuel production

GCB BIOENERGY, Issue 1 2009
DYLAN DODD
Abstract The combustion of fossil-derived fuels has a significant impact on atmospheric carbon dioxide (CO2) levels and correspondingly is an important contributor to anthropogenic global climate change. Plants have evolved photosynthetic mechanisms in which solar energy is used to fix CO2 into carbohydrates. Thus, combustion of biofuels, derived from plant biomass, can be considered a potentially carbon neutral process. One of the major limitations for efficient conversion of plant biomass to biofuels is the recalcitrant nature of the plant cell wall, which is composed mostly of lignocellulosic materials (lignin, cellulose, and hemicellulose). The heteropolymer xylan represents the most abundant hemicellulosic polysaccharide and is composed primarily of xylose, arabinose, and glucuronic acid. Microbes have evolved a plethora of enzymatic strategies for hydrolyzing xylan into its constituent sugars for subsequent fermentation to biofuels. Therefore, microorganisms are considered an important source of biocatalysts in the emerging biofuel industry. To produce an optimized enzymatic cocktail for xylan deconstruction, it will be valuable to gain insight at the molecular level of the chemical linkages and the mechanisms by which these enzymes recognize their substrates and catalyze their reactions. Recent advances in genomics, proteomics, and structural biology have revolutionized our understanding of the microbial xylanolytic enzymes. This review focuses on current understanding of the molecular basis for substrate specificity and catalysis by enzymes involved in xylan deconstruction. [source]

Gastrointestinal Morphology of the Crowned Lemur (Eulemur coronatus)

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 6 2009
C. Schwitzer
Summary I provide measurements of the gastrointestinal tract of a captive female Eulemur coronatus, obtained at necropsy, and describe its morphology. The small intestine, caecum and colon were short when compared with those of other lemur species. The ratio of intestine length to body length was low. Distinct sacculations were present in the caecum, but not in the colon. The results suggest that E. coronatus is able to digest a certain amount of structural polysaccharides as contained in plant cell wall. The main fermentation chamber seems to be the caecum. Its digestive morphology implies that E. coronatus relies on a diet higher in energy-rich cell contents than those of other lemur species of similar body size. [source]

Multiple crystal forms of the cell-wall invertase inhibitor from tobacco support high conformational rigidity over a broad pH range

ACTA CRYSTALLOGRAPHICA SECTION D, Issue 6 2006
Michael Hothorn
Plant acid invertases catalyse the breakdown of sucrose. Their activity is tightly regulated through interaction with specific protein inhibitors. The complex between the cell-wall invertase inhibitor Nt-CIF and its target enzyme is stable only at acidic pH, as found in the plant cell wall. Since the pH in this compartment can be modulated between pH 4 and 6 in planta, the rapid dissociation of the inhibitor,enzyme complex at neutral pH may represent a regulatory event. Here, it is analyzed whether the inhibitory component undergoes structural rearrangements upon changes in the pH environment. Six crystal forms grown at pH 4.6,9.5 and diffracting up to 1.63,Å indicate only small structural changes in CIF. This suggests that complex dissociation at neutral pH is mediated either by rearrangements in the enzyme or by a complex pattern of surface charges in the inhibitor,enzyme binding interface. [source]

Crystallization and preliminary X-ray characterization of a thermostable pectate lyase from Thermotoga maritima

ACTA CRYSTALLOGRAPHICA SECTION D, Issue 4 2002
Michael A. McDonough
Pectate lyase is an enzyme involved in the degradation of the pectate portion of the primary plant cell wall. A recombinant pectate lyase from Thermotoga maritima where three of the four cysteine residues have been mutated (C132I, C156N, C194L) has been crystallized. Crystals of the same morphology and trigonal space group R3 with similar unit-cell parameters were obtained under two different conditions. The first, 0.3,M (NH4)H2PO4 pH 4.2, gave crystals with a maximum size of 0.4 × 0.2 × 0.2,mm in one week that diffracted to a resolution of 1.87,Å and had unit-cell parameters a = b = 80.6, c = 148.8,Å. The second, 0.1,M sodium acetate, 6%(w/v) PEG 4000 pH 6.5, gave the same size crystals in two weeks that diffracted to a resolution of 2.1,Å and had unit-cell parameters a = b = 80.0, c = 150.1,Å. [source]

Indigestibility of plant cell wall by the Australian plague locust, Chortoicetes terminifera

Cell wall hemicelluloses as mobile carbon stores in non-reproductive plant tissues

FUNCTIONAL ECOLOGY, Issue 5 2007
G. HOCH
Summary 1As essential compounds of plant cell walls, hemicelluloses account for about a quarter of all plant biomass worldwide. 2In seed cotyledons and endosperm of species from several plant families, hemicelluloses are used as mobile carbon reserves. Whether cell wall hemicelluloses of non-reproductive plant tissue are multifunctional molecules, which can also serve as carbon sources during periods of enhanced carbon demand, is still equivocal. 3This review summarizes the current understanding of a possible reserve function of hemicelluloses. Although several descriptive and experimental studies suggested at least partial mobility of cell wall polysaccharides in mature, non-reproductive plant tissues, there is still a need for a broad-scale, ecophysiological exploration of the actual nature of hemicelluloses beyond their structural function. 4The chemical heterogeneity of hemicelluloses may be the major problem for precise quantitative analyses on a large, comparative scale. 5Because of the abundant distribution of hemicelluloses in plants, the existence of a significant mobile carbohydrate pool in cell walls of non-reproductive organs would shed rather new light on plant carbon relations in a source-sink context. 6Consequently, a reserve function of hemicelluloses questions the conventional division of cell compounds into structural (i.e. immobile) and non-structural (i.e. mobile) compounds. [source]

Impact of Harvesting and Processing Conditions on Green Leaf Volatile Development and Phenolics in Concord Grape Juice

JOURNAL OF FOOD SCIENCE, Issue 3 2010
M.M. Iyer
ABSTRACT:, The disruption of plant cell walls during fruit juice processing results in the enzymatic formation of herbaceous-smelling green leaf volatiles (GLVs). Our objective was to assess the impact of thermal processing conditions on resulting levels of GLVs (hexanal, trans -2-hexenal, hexanol, cis -3-hexenol, and trans -2-hexenol), total phenols, monomeric anthocyanins, and percent polymeric color in Concord grape juice. The effects of fruit maturity and stage of juice processing on juice GLV content was also assessed. Of the GLVs studied, only trans -2-hexenal routinely exceeded its published sensory threshold in finished juice. We observed an inverse linear correlation between berry maturity (total soluble solids) and trans -2-hexenal levels in finished juice (P,< 0.05, R 2= 0.91). Trans -2-hexenal was at a maximum immediately following crushing (569 ,g/kg, >30-fold over detection threshold [DT]), decreased to 100 ,g/kg following depectinization, pressing, and pasteurization, and to 32 ,g/kg following cold-stabilization. The loss of trans -2-hexenal could be explained primarily by its reduction to trans -2-hexenol, which increased from 53 ,g/kg after crushing to 500 ,g/kg after cold-stabilization. High temperature pretreatment of must immediately following crushing ("hot break") resulted in 5- to 6-fold higher concentrations of trans -2-hexenal in the final bottled juice as compared to conventional hot press. Contrary to expectations, no significant increase in phenolics and anthocyanins were observed in hot break conditions. These results indicate that hot break procedures may thermally inactivate enzymes responsible for transforming trans -2-hexenal under normal processing conditions and potentially alter the flavor qualities of the finished Concord juice. Different equivalent pasteurization regimes (82 to 93 °C) prior to bottling had no significant effect on GLV content of the finished Concord juices (P,> 0.05). Practical Application: Introducing new processing techniques to fruit juice production can potentially result in undesirable changes to organoleptic properties. We have observed significantly higher levels of trans- 2-hexenal, a potent herbaceous off-flavor, in Concord grape juice prepared with an initial high temperature heat treatment ("hot break"). Concord juice producers should be cautious in using hot break processing, especially with immature fruit, as it may result in persistence of green aromas in juice. [source]

Disruption of Cortical Microtubules by Overexpression of Green Fluorescent Protein-Tagged ,-Tubulin 6 Causes a Marked Reduction in Cell Wall Synthesis

JOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 1 2006
David H. Burk
Abstract It has been known that the transverse orientation of cortical microtubules (MTs) along the elongation axis is essential for normal cell morphogenesis, but whether cortical MTs are essential for normal cell wall synthesis is still not clear. In the present study, we have investigated whether cortical MTs affect cell wall synthesis by direct alteration of the cortical MT organization in Arabidopsis thaliana. Disruption of the cortical MT organization by expression of an excess amount of green fluorescent protein-tagged ,-tubulin 6 (GFP-TUA6) in transgenic Arabidopsis plants was found to cause a marked reduction in cell wall thickness and a decrease in the cell wall sugars glucose and xylose. Concomitantly, the stem strength of the GFP-TUA6 overexpressors was markedly reduced compared with the wild type. In addition, expression of excess GFP-TUA6 results in an alteration in cell morphogenesis and a severe effect on plant growth and development. Together, these results suggest that the proper organization of cortical MTs is essential for the normal synthesis of plant cell walls. (Managing editor: Wei Wang) [source]

Characterization of nonderivatized plant cell walls using high-resolution solution-state NMR spectroscopy,

MAGNETIC RESONANCE IN CHEMISTRY, Issue 6 2008
Daniel J. Yelle
Abstract A recently described plant cell wall dissolution system has been modified to use perdeuterated solvents to allow direct in-NMR-tube dissolution and high-resolution solution-state NMR of the whole cell wall without derivatization. Finely ground cell wall material dissolves in a solvent system containing dimethylsulfoxide- d6 and 1-methylimidazole- d6 in a ratio of 4:1 (v/v), keeping wood component structures mainly intact in their near-native state. Two-dimensional NMR experiments, using gradient-HSQC (heteronuclear single quantum coherence) 1-bond 13C1H correlation spectroscopy, on nonderivatized cell wall material from a representative gymnosperm pinus taeda (loblolly pine), an angiosperm Populus tremuloides (quaking aspen), and a herbaceous plant Hibiscus cannabinus (kenaf) demonstrate the efficacy of the system. We describe a method to synthesize 1-methylimidazole- d6 with a high degree of perdeuteration, thus allowing cell wall dissolution and NMR characterization of nonderivatized plant cell wall structures. Copyright © 2008 John Wiley & Sons, Ltd. [source]

Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: An update covering the period 2001,2002

MASS SPECTROMETRY REVIEWS, Issue 2 2008
David J. Harvey
Abstract This review is the second update of the original review on the application of MALDI mass spectrometry to the analysis of carbohydrates and glycoconjugates that was published in 1999. It covers fundamental aspects of the technique as applied to carbohydrates, fragmentation of carbohydrates, studies of specific carbohydrate types such as those from plant cell walls and those attached to proteins and lipids, studies of glycosyl-transferases and glycosidases, and studies where MALDI has been used to monitor products of chemical synthesis. Use of the technique shows a steady annual increase at the expense of older techniques such as FAB. There is an increasing emphasis on its use for examination of biological systems rather than on studies of fundamental aspects and method development and this is reflected by much of the work on applications appearing in tabular form. © 2008 Wiley Periodicals, Inc., Mass Spec Rev 27:125,201, 2008 [source]

The RhaS activator controls the Erwinia chrysanthemi 3937 genes rhiN, rhiT and rhiE involved in rhamnogalacturonan catabolism

MOLECULAR MICROBIOLOGY, Issue 5 2004
Nicole Hugouvieux-Cotte-Pattat
Summary Erwinia chrysanthemi causes soft-rot diseases of various plants by enzymatic degradation of the pectin in plant cell walls. The linear regions of pectin are composed of an acidic sugar, d -galacturonic acid. The ramified regions of pectin also include neutral sugars, and are rich in l -rhamnose residues. E. chrysanthemi is able to degrade these polysaccharides, polygalacturonate and rhamnogalacturonate. In E. chrysanthemi, the production of pectinases acting on linear regions is induced in the presence of polygalacturonate by a mechanism involving the repressor KdgR. The induction of the two adjacent E. chrysanthemi genes, designated rhiT and rhiN, is maximal after the simultaneous addition of both polygalacturonate and l -rhamnose. The rhiT product is homologous to the oligogalacturonide transporter TogT of E. chrysanthemi. The rhiN product is homologous to various proteins of unknown function, including a protein encoded by the plant-inducible locus picA of Agrobacterium tumefaciens. Both rhiT and rhiN are highly induced during plant infection. Various data suggest that RhiT and RhiN are involved in rhamnogalacturonate catabolism. RhiN is able to degrade the oligomers liberated by the rhamnogalacturonate lyase RhiE. The induction of the rhiTN operon in the presence of polygalacturonate results from control by the repressor KdgR. The additional induction of these genes by rhamnose is directly mediated by RhaS, a protein homologous to the activator of rhamnose catabolism in Escherichia coli. The virulence of an E. chrysanthemi rhaS mutant towards different host plants was clearly reduced. In this phytopathogenic bacterial species, RhaS positively regulates the transcription of the rhaBAD operon, involved in rhamnose catabolism, of the rhiE gene and of the rhiTN operon. The regulator RhaS plays a larger role in E. chrysanthemi than in other enterobacteria. Indeed, the RhaS control is not restricted to the catabolism of rhamnose but is extended to the degradation of plant polysaccharides that contain this sugar. [source]

Hemicellulose concentration and composition in plant cell walls under extreme carbon source,sink imbalances

PHYSIOLOGIA PLANTARUM, Issue 3 2010
Christina Schädel
Hemicelluloses account for one-quarter of the global dry plant biomass and therefore are the second most abundant biomass fraction after cellulose. Despite their quantitative significance, the responsiveness of hemicelluloses to atmospheric carbon oversupply is still largely unknown, although hemicelluloses could serve as carbon sinks with increasing CO2 concentrations. This study aimed at clarifying the role hemicelluloses play as carbon sinks, analogous to non-structural carbohydrates (NSC), by experimentally manipulating the plants' carbon supply. Sixteen plant species from four different plant functional types (grasses, herbs, seedlings of broad-leaved trees and conifers) were grown for 2 months in greenhouses at either extremely low (140 ppm), medium (280 ppm) or high (560 ppm) atmospheric CO2 concentrations, thus inducing situations of massive C-limitation or -oversupply. Above and belowground biomass as well as NSC significantly increased in all species and tissues with increasing CO2 concentrations. Increasing CO2 concentrations had no significant effect on total hemicellulose concentrations in leaves and woody tissues in all species, except for two out of four grass species, where hemicellulose concentrations increased with atmospheric CO2 supply. Despite the overall stable total hemicellulose concentrations, the monosaccharide spectra of hemicelluloses showed a significant increase in glucose monomers in leaves of woody species as C-supply increased. In summary, total hemicellulose concentrations in de novo built biomass seem to be largely unaffected by changed atmospheric CO2 concentrations, while significant increases of hemicellulose-derived glucose with increasing CO2 concentrations in leaves of broad-leaved and conifer tree seedlings showed differential responses among the different hemicellulose classes in response to varying CO2 concentrations. [source]

The hydroxyproline-rich glycoprotein domain of the Arabidopsis LRX1 requires Tyr for function but not for insolubilization in the cell wall

THE PLANT JOURNAL, Issue 4 2010
Christoph Ringli
Summary Extensins, hydroxyproline-rich repetitive glycoproteins with Ser,Hyp4 motifs, are structural proteins in plant cell walls. The leucine-rich repeat extensin 1 (LRX1) of Arabidopsis thaliana is an extracellular protein with both a leucine-rich repeat and an extensin domain, and has been demonstrated to be important for cell-wall formation in root hairs. lrx1 mutants develop defective cell walls, resulting in a strong root hair phenotype. The extensin domain is essential for protein function and is thought to confer insolubilization of LRX1 in the cell wall. Here, in vivo characterization of the LRX1 extensin domain is described. First, a series of LRX1 extensin deletion constructs was produced that led to identification of a much shorter, functional extensin domain. Tyr residues can induce intra- and inter-molecular cross-links in extensins, and substitution of Tyr in the extensin domain by Phe led to reduced activity of the corresponding LRX1 protein. An additional function of Tyr (or Phe) is provided by the aromatic nature of the side chain. This suggests that these residues might be involved in hydrophobic stacking, possibly as a mechanism of protein assembly. Finally, modified LRX1 proteins lacking Tyr in the extensin domain are still insolubilized in the cell wall, indicating strong interactions of extensins within the cell wall in addition to the well-described Tyr cross-links. [source]

Disruption of ATCSLD5 results in reduced growth, reduced xylan and homogalacturonan synthase activity and altered xylan occurrence in Arabidopsis

THE PLANT JOURNAL, Issue 5 2007
Adriana Jimena Bernal
Summary Members of a large family of cellulose synthase-like genes (CSLs) are predicted to encode glycosyl transferases (GTs) involved in the biosynthesis of plant cell walls. The CSLA and CSLF families are known to contain mannan and glucan synthases, respectively, but the products of other CSLs are unknown. Here we report the effects of disrupting ATCSLD5 expression in Arabidopsis. Both stem and root growth were significantly reduced in ATCSLD5 knock-out plants, and these plants also had increased susceptibility to the cellulose synthase inhibitor isoxaben. Antibody and carbohydrate-binding module labelling indicated a reduction in the level of xylan in stems, and in vitro GT assays using microsomes from stems revealed that ATCSLD5 knock-out plants also had reduced xylan and homogalacturonan synthase activity. Expression in Nicotiana benthamiana of ATCSLD5 and ATCSLD3, fluorescently tagged at either the C- or the N-terminal, indicated that these GTs are likely to be localized in the Golgi apparatus. However, the position of the fluorescent tag affected the subcellular localization of both proteins. The work presented provides a comprehensive analysis of the effects of disrupting ATCSLD5 in planta, and the possible role(s) of this gene and other ATCSLDs in cell wall biosynthesis are discussed. [source]

Crystallization and preliminary X-ray studies of xylanase 10B from Thermotoga maritima

ACTA CRYSTALLOGRAPHICA SECTION D, Issue 9 2003
Ihsanawati
Xylanases catalyze the hydrolysis of the ,-1,4-glycosidic bonds of xylan, which is the second most abundant component of plant cell walls after cellulose. The recombinant xylanase 10B from Thermotoga maritima MSB8 was prepared and crystallized by the sitting-drop vapour-diffusion method using 40,mM zinc acetate, 20,mM MES buffer pH 6.0 and 3% ethanol. Intensity data were collected to 2.5,Å resolution at beamline BL26B2 of SPring-8. Preliminary X-ray analysis showed that the crystal belongs to space group P21212, with unit-cell parameters a = 77.3, b = 80.6, c = 58.2,Å and one molecule per asymmetric unit. [source]

Standard assays do not predict the efficiency of commercial cellulase preparations towards plant materials

BIOTECHNOLOGY & BIOENGINEERING, Issue 1 2006
Mirjam A. Kabel
Abstract Commercial cellulase preparations are potentially effective for processing biomass feedstocks in order to obtain bioethanol. In plant cell walls, cellulose fibrils occur in close association with xylans (monocotyls) or xyloglucans (dicotyls). The enzymatic conversion of cellulose/xylans is a complex process involving the concerted action of exo/endocellulases and cellobiases yielding glucose and xylanases yielding xylooligomers and xylose. An overview of commonly measured cellulase-, cellobiase-, and xylanase-activity, using respectively filter paper, cellobiose, and AZCL-dyed xylan as a substrate of 14 commercially available enzyme preparations from several suppliers is presented. In addition to these standardized tests, the enzyme-efficiency of degrading native substrates was studied. Grass and wheat bran were fractionated into a water unsoluble fraction (WUS), which was free of oligosaccharides and starch. Additionally, cellulose- and xylan-rich fractions were prepared by alkaline extraction of the WUS and were enzymatically digested. Hereby, the capability of cellulose and xylan conversion of the commercial enzyme preparations tested was measured. The results obtained showed that there was a large difference in the performance of the fourteen enzyme samples. Comparing all results, it was concluded that the choice of an enzyme preparation is more dependent on the characteristics of the substrate rather than on standard enzyme-activities measured. © 2005 Wiley Periodicals, Inc. [source]

Enemy at the gates: traffic at the plant cell pathogen interface

CELLULAR MICROBIOLOGY, Issue 12 2008
Caroline Hoefle
Summary The plant apoplast constitutes a space for early recognition of potentially harmful non-self. Basal pathogen recognition operates via dynamic sensing of conserved microbial patterns by pattern recognition receptors or of elicitor-active molecules released from plant cell walls during infection. Recognition elicits defence reactions depending on cellular export via SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) complex-mediated vesicle fusion or plasma membrane transporter activity. Lipid rafts appear also involved in focusing immunity-associated proteins to the site of pathogen contact. Simultaneously, pathogen effectors target recognition, apoplastic host proteins and transport for cell wall-associated defence. This microreview highlights most recent reports on the arms race for plant disease and immunity at the cell surface. [source]