Departamento de Bioquímica, CCB, Universidade Federal de Pernambuco, Cidade Universitária, 50670-420 Recife, Pernambuco, Brazil.
Parasitol Res. 2012 Feb;110(2):609-16. doi: 10.1007/s00436-011-2529-7. Epub 2011 Jul 7.
Aedes aegypti transmits the viruses that cause yellow and dengue fevers. Vector control is essential, since a vaccine for dengue has not as yet been made available. This work reports on the larvicidal activity of Myracrodruon urundeuva leaf lectin (MuLL) against A. aegypti fourth-stage larvae (L(4)). Also, the resistance of MuLL to digestion by L(4) gut proteases and the effects of MuLL on protease, trypsin-like and α-amylase activities from L(4) gut were evaluated to determine if lectin remains active in A. aegypti gut and if insect enzyme activities can be modulated by MuLL. MuLL promoted mortality of L(4) with LC(50) of 0.202 mg/ml. Haemagglutinating activity of MuLL was detected even after incubation for 96 h with L(4) gut preparation containing protease activity. MuLL affected the activity of gut enzymes, inhibiting protease and trypsin activities and stimulating α-amylase activity. The results suggest that MuLL may become a new biodegradable larvicidal agent for dengue control. Larvicidal activity of MuLL may be linked to its resistance to proteolysis by larval enzymes and interference in the activity of digestive larval enzymes.
埃及伊蚊传播引起黄热病和登革热的病毒。由于尚未开发出登革热疫苗，因此必须进行病媒控制。这项工作报道了 Myracrodruon urundeuva 叶凝集素 (MuLL) 对埃及伊蚊第四期幼虫 (L(4)) 的杀幼虫活性。此外，还评估了 MuLL 对 L(4) 肠道蛋白酶消化的抗性以及 MuLL 对 L(4) 肠道蛋白酶、胰蛋白酶样和 α-淀粉酶活性的影响，以确定凝集素是否在埃及伊蚊肠道中保持活性，以及昆虫酶活性是否可以被 MuLL 调节。MuLL 以 LC(50) 为 0.202 mg/ml 的浓度促进了 L(4) 的死亡。即使在用含有蛋白酶活性的 L(4) 肠道制剂孵育 96 小时后，也检测到 MuLL 的血凝活性。MuLL 影响肠道酶的活性，抑制蛋白酶和胰蛋白酶活性，刺激 α-淀粉酶活性。结果表明，MuLL 可能成为控制登革热的新型可生物降解的杀幼虫剂。MuLL 的杀幼虫活性可能与其对幼虫酶的蛋白水解抗性以及对消化幼虫酶活性的干扰有关。
