Portrayal of Complex Dynamic Properties of Sugarcane Defensin 5 by NMR: Multiple Motions Associated with Membrane Interaction

Paula, Viviane de; Razzera, Guilherme; Barreto‐Bergter, Eliana; Almeida, Fábio C. L.; Valente, Ana Paula

doi:10.1016/j.str.2010.11.011

Cited by 54 publications

(97 citation statements)

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“…The Lβ 2 β 3 loop has also been connected with other biological activities associated with plant defensins, including anti insecticidal activity and enzyme inhibition [36,78]. The Lβ 2 β 3 loop is not the only area of the peptide structure that plays a role in antifungal activity and recently a role for the loop connecting the α-helix and first β-strand have been proposed for the interaction of plant defensins with their fungal target [89,90], an area where the Hc-AFPs show high sequence divergence and a deviation of 1.6 Å when the structures are superimposed (Figure 5G and 5H). …”

Section: Discussionmentioning

confidence: 99%

Four plant defensins from an indigenous South African Brassicaceae species display divergent activities against two test pathogens despite high sequence similarity in the encoding genes

Beer

Vivier

2011

BMC Res Notes

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BackgroundPlant defensins are an important component of the innate defence system of plants where they form protective antimicrobial barriers between tissue types of plant organs as well as around seeds. These peptides also have other activities that are important for agricultural applications as well as the medical sector. Amongst the numerous plant peptides isolated from a variety of plant species, a significant number of promising defensins have been isolated from Brassicaceae species. Here we report on the isolation and characterization of four defensins from Heliophila coronopifolia, a native South African Brassicaceae species.ResultsFour defensin genes (Hc-AFP1-4) were isolated with a homology based PCR strategy. Analysis of the deduced amino acid sequences showed that the peptides were 72% similar and grouped closest to defensins isolated from other Brassicaceae species. The Hc-AFP1 and 3 peptides shared high homology (94%) and formed a unique grouping in the Brassicaceae defensins, whereas Hc-AFP2 and 4 formed a second homology grouping with defensins from Arabidopsis and Raphanus. Homology modelling showed that the few amino acids that differed between the four peptides had an effect on the surface properties of the defensins, specifically in the alpha-helix and the loop connecting the second and third beta-strands. These areas are implicated in determining differential activities of defensins. Comparing the activities after recombinant production of the peptides, Hc-AFP2 and 4 had IC50 values of 5-20 μg ml-1 against two test pathogens, whereas Hc-AFP1 and 3 were less active. The activity against Botrytis cinerea was associated with membrane permeabilization, hyper-branching, biomass reduction and even lytic activity. In contrast, only Hc-AFP2 and 4 caused membrane permeabilization and severe hyper-branching against the wilting pathogen Fusarium solani, while Hc-AFP1 and 3 had a mild morphogenetic effect on the fungus, without any indication of membrane activity. The peptides have a tissue-specific expression pattern since differential gene expression was observed in the native host. Hc-AFP1 and 3 expressed in mature leaves, stems and flowers, whereas Hc-AFP2 and 4 exclusively expressed in seedpods and seeds.ConclusionsTwo novel Brassicaceae defensin sequences were isolated amongst a group of four defensin encoding genes from the indigenous South African plant H. coronopifolia. All four peptides were active against two test pathogens, but displayed differential activities and modes of action. The expression patterns of the peptide encoding genes suggest a role in protecting either vegetative or reproductive structures in the native host against pathogen attack, or roles in unknown developmental and physiological processes in these tissues, as was shown with other defensins.

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Section: Discussionmentioning

confidence: 99%

Four plant defensins from an indigenous South African Brassicaceae species display divergent activities against two test pathogens despite high sequence similarity in the encoding genes

Beer

Vivier

2011

BMC Res Notes

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“…Plant defensins that bind sphingolipids include RsAFP2 from radish (binds glucosylceramide, GlcCer) (Thomma et al, 2003; Thevissen et al, 2004), DmAMP1 from dahlia (binds mannose-(inositol-phosphate) 2 -ceramide, M(IP) 2 C) (Thevissen et al, 2000, 2003), as well as the pea defensin Psd1 (Goncalves et al, 2012) and sugarcane defensin Sd5 (de Paula et al, 2011) that both bind membranes enriched for specific glycosphingolipids. MsDef1, a defensin from Medicago sativa , has also been implicated in binding sphingolipids, as a mutant of the fungus Fusarium graminearum that is depleted in glucosylceramide, is highly resistant to MsDef1 (Ramamoorthy et al, 2007).…”

Section: Introductionmentioning

confidence: 99%

Phosphoinositide-mediated oligomerization of a defensin induces cell lysis

Poon

Baxter

Lay

et al. 2014

eLife

167

247

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Cationic antimicrobial peptides (CAPs) such as defensins are ubiquitously found innate immune molecules that often exhibit broad activity against microbial pathogens and mammalian tumor cells. Many CAPs act at the plasma membrane of cells leading to membrane destabilization and permeabilization. In this study, we describe a novel cell lysis mechanism for fungal and tumor cells by the plant defensin NaD1 that acts via direct binding to the plasma membrane phospholipid phosphatidylinositol 4,5-bisphosphate (PIP2). We determined the crystal structure of a NaD1:PIP2 complex, revealing a striking oligomeric arrangement comprising seven dimers of NaD1 that cooperatively bind the anionic headgroups of 14 PIP2 molecules through a unique ‘cationic grip’ configuration. Site-directed mutagenesis of NaD1 confirms that PIP2-mediated oligomerization is important for fungal and tumor cell permeabilization. These observations identify an innate recognition system by NaD1 for direct binding of PIP2 that permeabilizes cells via a novel membrane disrupting mechanism.DOI: http://dx.doi.org/10.7554/eLife.01808.001

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“…In an attempt to understand their interactions with biomembranes, AMP structures were determined by NMR, both in solution and in the presence of interfaces (10)(11)(12). AMPs frequently convert between different conformations in solution, acquiring more stable conformations upon binding to interfaces (1,(13)(14)(15)(16)(17)(18)(19).…”

Section: Introductionmentioning

confidence: 99%

“…AMPs frequently convert between different conformations in solution, acquiring more stable conformations upon binding to interfaces (1,(13)(14)(15)(16)(17)(18)(19). NMR is a powerful technique for studying such dynamic systems (1,10). The nuclear Overhauser effect (NOE) can be used to calculate the structure of AMPs, whereas chemical-shift changes and paramagnetic effects can be used to evaluate interactions with interfaces (1,20,21).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Structural and Dynamic Insights of the Interaction between Tritrpticin and Micelles: An NMR Study

Santos

Moraes

Nakaie

et al. 2016

Biophysical Journal

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A large number of antimicrobial peptides (AMPs) acts with high selectivity and specificity through interactions with membrane lipid components. These peptides undergo complex conformational changes in solution; upon binding to an interface, one major conformation is stabilized. Here we describe a study of the interaction between tritrpticin (TRP3), a cathelicidin AMP, and micelles of different chemical composition. The peptide's structure and dynamics were examined using one-dimensional and two-dimensional NMR. Our data showed that the interaction occurred by conformational selection and the peptide acquired similar structures in all systems studied, despite differences in detergent headgroup charge or dipole orientation. Fluorescence and paramagnetic relaxation enhancement experiments showed that the peptide is located in the interface region and is slightly more deeply inserted in 1-myristoyl-2-hydroxy-sn-glycero-3-phospho-1 0 -rac-glycerol (LMPG, anionic) than in 1-lauroyl-2-hydroxy-sn-glycero-3-phosphocholine (LLPC, zwitterionic) micelles. Moreover, the tilt angle of an assumed helical portion of the peptide is similar in both systems. In previous work we proposed that TRP3 acts by a toroidal pore mechanism. In view of the high hydrophobic core exposure, hydration, and curvature presented by micelles, the conformation of TRP3 in these systems could be related to the peptide's conformation in the toroidal pore.

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Portrayal of Complex Dynamic Properties of Sugarcane Defensin 5 by NMR: Multiple Motions Associated with Membrane Interaction

Cited by 54 publications

References 48 publications

Four plant defensins from an indigenous South African Brassicaceae species display divergent activities against two test pathogens despite high sequence similarity in the encoding genes

Four plant defensins from an indigenous South African Brassicaceae species display divergent activities against two test pathogens despite high sequence similarity in the encoding genes

Phosphoinositide-mediated oligomerization of a defensin induces cell lysis

Structural and Dynamic Insights of the Interaction between Tritrpticin and Micelles: An NMR Study

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