Dhananjeyan K J, Sivaperumal R, Paramasivan R, Thenmozhi V, Tyagi B K
Centre for Research in Medical Entomology, Indian Council of Medical Research, 4 Sarojini Street, Chinna Chokkikulam, Madurai 625002 Tamil Nadu, India.
J Mol Model. 2009 May;15(5):507-14. doi: 10.1007/s00894-008-0408-7. Epub 2008 Dec 16.
Dengue is a serious public health problem in tropical and subtropical countries. It is caused by any of the four serologically distinct dengue viruses, namely DENV1-4. The viruses are transmitted by Aedes mosquitoes. Understanding various defence mechanisms of insects has become a prime area of research worldwide. In insects, the first line of defence against invading pathogens includes cellular mechanisms and a battery of antimicrobial peptides such as defensins, cecropins etc. Defensins--cationic, cysteine-rich peptides consisting of approximately 40 amino acids with broad-spectrum activity against Gram-positive bacteria--have been reported from a wide range of organisms. In the dengue vector mosquito, Aedes aegypti, three isoforms of defensins are reported to be expressed in a spatial and temporal fashion. This report presents the three-dimensional structures of the three isoforms of Ae. aegypti defensins predicted by comparative modeling. Prediction was done with Modeller 9v1 and the structures validated through a series of tests. The best results of the prediction study are presented, and may help lead to the discovery of new synthetic peptides or derivatives of defensins that could be useful in the control of vector-borne diseases.
登革热在热带和亚热带国家是一个严重的公共卫生问题。它由四种血清学上不同的登革热病毒中的任何一种引起，即登革病毒1 - 4型。这些病毒通过伊蚊传播。了解昆虫的各种防御机制已成为全球研究的一个主要领域。在昆虫中，抵御入侵病原体的第一道防线包括细胞机制和一系列抗菌肽，如防御素、天蚕素等。防御素是一种阳离子、富含半胱氨酸的肽，由大约40个氨基酸组成，对革兰氏阳性菌具有广谱活性，已在多种生物体中被报道。在登革热传播媒介蚊子埃及伊蚊中，据报道三种防御素同工型以时空方式表达。本报告展示了通过比较建模预测的埃及伊蚊三种防御素同工型的三维结构。使用Modeller 9v1进行预测，并通过一系列测试对结构进行验证。展示了预测研究的最佳结果，这可能有助于发现可用于控制媒介传播疾病的新型合成肽或防御素衍生物。
