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<section class="content_container"> | <section class="content_container"> | ||
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− | <p class="title">What is | + | <p class="title">What is “Pantide”?<p> |
− | <p class="content"> | + | <p class="content">Pantide, a portmanteau word, conveys two concept- Pan and peptide- in a single blended neologism. In ancient Greek mythology, Pan is a god of shepherds and nature, whereas peptide indicates the essential substance of Pantide, amino acids. Pantide derives its toxicity from the spider venom. The inspiration for Pantide originates from the food chain. Predation is a scene ubiquitously observed in nature. Through evolution, animals have evolved diverse ways of predatory strategy. In this light, we hope to avail the natural evolutionary phenomenon into our project. Spiders are one of the most successful terrestrial venomous creatures on earth. In 300 million years of evolution, spiders have evolved arrays of complex venomous toxins. <sup>[1]</sup> Therefore, we find it potential for integrating spider toxins as a new source of bioinsecticide.</p> |
<p class="quote">“More than a hundred different components can be found in the same venom, and in this parameter spiders are leaders in living nature.”</p> | <p class="quote">“More than a hundred different components can be found in the same venom, and in this parameter spiders are leaders in living nature.”</p> | ||
<p style="text-align:right"class="quote">Professor Alexander Vassilevski et al<br> | <p style="text-align:right"class="quote">Professor Alexander Vassilevski et al<br> | ||
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<li class="list">The toxin was done with some orally-active experiment on certain species.</li> | <li class="list">The toxin was done with some orally-active experiment on certain species.</li> | ||
<li class="list">The toxin has no antibiotic activity to bacteria.</li> | <li class="list">The toxin has no antibiotic activity to bacteria.</li> | ||
− | <p class="content">After months of searching and winnowing, | + | <p class="content">After months of searching and winnowing, Pantide comes into existence. The three selected toxins are Omega-hexatoxin-Hv1a(Hv1a), μ-segestritoxin-Sf1a(Sf1a) and Orally active insecticidal peptide(OAIP).</p> |
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<p class="content">OAIP is a toxic peptide derived from Selenotypus plumipes (Australian featherleg tarantula). It targets the voltage-gated ion channel of insects including species from the orders Lepidoptera and Coleoptera. It causes paralysis and finally death. OAIP is lethal to several insect orders but is not toxic to mice. <sup>[5]</sup></p> | <p class="content">OAIP is a toxic peptide derived from Selenotypus plumipes (Australian featherleg tarantula). It targets the voltage-gated ion channel of insects including species from the orders Lepidoptera and Coleoptera. It causes paralysis and finally death. OAIP is lethal to several insect orders but is not toxic to mice. <sup>[5]</sup></p> | ||
<p class="content">The three toxins are belong to a major category in spider venom-Short peptides that have disulfide bonds. Most of these toxin peptides have a structural motif that contains cysteine knottings and forms loops. The active site in the peptide that performs its toxicity are the amino acids located in loop regions. <sup>[6]</sup> The structure of these toxins are so-called “Inhibitor Cystine Knot (ICK)”. ICK has several features based on its disulfide-bond-rich structure-Stability. Take Hv1a as an example for proving the stability of ICK; Hv1a is highly stable in the temperature range of -20°C to 75°C and ph values of 1 to 8. Also, Hv1a is resistant to digestive enzyme-protease K. <sup>[7]</sup></p> | <p class="content">The three toxins are belong to a major category in spider venom-Short peptides that have disulfide bonds. Most of these toxin peptides have a structural motif that contains cysteine knottings and forms loops. The active site in the peptide that performs its toxicity are the amino acids located in loop regions. <sup>[6]</sup> The structure of these toxins are so-called “Inhibitor Cystine Knot (ICK)”. ICK has several features based on its disulfide-bond-rich structure-Stability. Take Hv1a as an example for proving the stability of ICK; Hv1a is highly stable in the temperature range of -20°C to 75°C and ph values of 1 to 8. Also, Hv1a is resistant to digestive enzyme-protease K. <sup>[7]</sup></p> | ||
− | <p class="content">In nature, spiders inject venom into the haemolymph of insects’ that causes the death of the prey. However, | + | <p class="content">In nature, spiders inject venom into the haemolymph of insects’ that causes the death of the prey. However, Pantide is designed to be ingested by pests after application of Pantide onto the leaves. Therefore, there should be an amelioration done for the design of toxin.</p> |
<p class="quote">“Many insecticidal venom peptides are typically ineffective, or at least much less potent, when delivered orally and this is thought to be due to the ineffective delivery of the toxins to their active sites of action in the central nervous system or peripheral nervous system.”</p> | <p class="quote">“Many insecticidal venom peptides are typically ineffective, or at least much less potent, when delivered orally and this is thought to be due to the ineffective delivery of the toxins to their active sites of action in the central nervous system or peripheral nervous system.”</p> | ||
<p class="quote" style="text-align:right">Doctor Elaine C. Fitches et al<br> | <p class="quote" style="text-align:right">Doctor Elaine C. Fitches et al<br> | ||
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<div> | <div> | ||
− | <p class="title">Qualities of | + | <p class="title">Qualities of Pantide</p> |
− | <p class="content"> | + | <p class="content">Pantide is an all-natural bioinsecticide with four promising features-eco-friendly, safe, biodegradable, and species specific.</p> |
− | <p class="content">In contrast to chemical pesticide, | + | <p class="content">In contrast to chemical pesticide, Pantide will not pollute rivers and soil in the environment, which is eco-friendly. Besides, due to structural difference of ion channels between insects and mammals, Pantide is non-toxic to mammals. The traditional pesticide will kill all the insects in the farmland no matter it is pest or not. The issue mentioned above is an urgent problem, here’s an example. Imidacloprid, a chemical insecticide with relatively low toxicity to human, cannot avoid causing CCD (Colony Collapsed Disorder) that impair the major pollinators, bees. To tackle this problem, Pantide is species specific to several orders of pests, Hv1a targets Lepidopteran, Orthopteran, and Dipteran, Sf1a targets Lepidopteran, and Dipteran, OAIP targets Lepidopteran and Coleopteran. Another apprehension about nowadays insecticidal pesticide is that through bioaccumulation, the pesticide chemical residue will accumulate in the human body, and can’t be degraded by us. However, Pantide is made of amino acids so it will degrade over time by the protease in the environment.</p> |
− | <p class="content">In comparison with another biological pesticide, Bacillus thuringiensis, | + | <p class="content">In comparison with another biological pesticide, Bacillus thuringiensis, Pantide comprises three different peptides, Hv1a, OAIP, and Sf1a that target calcium and sodium ion channels respectively. By using these three peptides alternately, the pest is hard to have resistance. Furthermore, ion channel has a low frequency of evolution. These features ensure Pantide can fight against pest for a long time without resistance. </p> |
<p class="content">References</p> | <p class="content">References</p> | ||
</div> | </div> |
Revision as of 16:59, 19 October 2016