55 research outputs found
Solid-state NMR reveals structural differences between fibrils of wild-type and disease-related A53T mutant α-synuclein.
Primary steps of pH-dependent insulin aggregation kinetics are governed by conformational flexibility.
High toxicity and specificity of the saponin 3-GlcA-28-AraRhaxyl-medicagenate, from Medicago truncatula seeds, for Sitophilus oryzae
<p>Abstract</p> <p>Background</p> <p>Because of the increasingly concern of consumers and public policy about problems for environment and for public health due to chemical pesticides, the search for molecules more safe is currently of great importance. Particularly, plants are able to fight the pathogens as insects, bacteria or fungi; so that plants could represent a valuable source of new molecules.</p> <p>Results</p> <p>It was observed that <it>Medicago truncatul</it>a seed flour displayed a strong toxic activity towards the adults of the rice weevil <it>Sitophilus oryzae</it> (Coleoptera), a major pest of stored cereals. The molecule responsible for toxicity was purified, by solvent extraction and HPLC, and identified as a saponin, namely 3-GlcA-28-AraRhaxyl-medicagenate. Saponins are detergents, and the CMC of this molecule was found to be 0.65âmg per mL. Neither the worm <it>Caenorhabditis elegans</it> nor the bacteria <it>E. coli</it> were found to be sensitive to this saponin, but growth of the yeast <it>Saccharomyces cerevisiae</it> was inhibited at concentrations higher than 100âÎŒg per mL. The purified molecule is toxic for the adults of the rice weevils at concentrations down to 100âÎŒg per g of food, but this does not apply to the others insects tested, including the coleopteran <it>Tribolium castaneum</it> and the Sf9 insect cultured cells.</p> <p>Conclusions</p> <p>This specificity for the weevil led us to investigate this saponin potential for pest control and to propose the hypothesis that this saponin has a specific mode of action, rather than acting <it>via</it> its non-specific detergent properties.</p
Identifying water stress-response mechanisms in citrus by in silico transcriptome analysis
Massenspektroskopie und ihre Anwendung auf strukturelle und stereochemische Probleme, 44. Mitt.: Das Fragmentierungsverhalten monocyclischer Ketone
Water-stress response in aspen (Populus tremula): Differential accumulation of dehydrin, sucrose synthase, GAPDH homologues, and soluble sugars
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