Kamita Shizuo G, Hinton Andrew C, Wheelock Craig E, Wogulis Mark D, Wilson David K, Wolf Nicola M, Stok Jeanette E, Hock Bertold, Hammock Bruce D
Department of Entomology and Cancer Research Center, University of California, 303 Briggs Hall, 1 Shields Avenue, Davis, CA 95616, USA.
Insect Biochem Mol Biol. 2003 Dec;33(12):1261-73. doi: 10.1016/j.ibmb.2003.08.004.
Juvenile hormone esterases (JHEs) from six insects belonging to three orders (Lepidoptera, Coleoptera, and Diptera) were compared in terms of their deduced amino acid sequence and biochemical properties. The four lepidopteran JHEs showed from 52% to 59% identity to each other and about 30% identity to the coleopteran and dipteran JHEs. The JHE of Manduca sexta was remarkably resistant to the addition of organic co-solvents and detergent; in some cases, it demonstrated significant activation of activity. Trifluoromethylketone (TFK) inhibitors with chain lengths of 8, 10 or 12 carbons were highly effective against both lepidopteran and coleopteran JHEs. The coleopteran JHE remained sensitive to TFK inhibitors with a chain length of 6 carbons, whereas the lepidopteran JHEs were significantly less sensitive. When the chain was altered to a phenethyl moiety, the coleopteran JHE remained moderately sensitive, while the lepidopteran JHEs were much less sensitive. The lepidopteran and coleopteran JHEs did not show dramatic differences in specificity to alpha-naphthyl and rho-nitrophenyl substrates. However, as the chain length of the alpha-naphthyl substrates increased from propionate to caprylate, there was a trend towards reduced activity. The JHE of M. sexta was crystallized and the properties of the crystal suggest a high-resolution structure will follow.
对来自三个目（鳞翅目、鞘翅目和双翅目）的六种昆虫的保幼激素酯酶（JHEs）的推导氨基酸序列和生化特性进行了比较。四种鳞翅目JHEs彼此之间的同一性为52%至59%，与鞘翅目和双翅目JHEs的同一性约为30%。烟草天蛾的JHE对添加有机共溶剂和洗涤剂具有显著抗性；在某些情况下，它表现出活性的显著激活。碳链长度为8、10或12的三氟甲基酮（TFK）抑制剂对鳞翅目和鞘翅目JHEs均高效。碳链长度为6的TFK抑制剂对鞘翅目JHE仍敏感，而鳞翅目JHEs的敏感性则显著较低。当碳链改为苯乙基部分时，鞘翅目JHE仍保持适度敏感，而鳞翅目JHEs的敏感性则低得多。鳞翅目和鞘翅目JHEs对α-萘基和对硝基苯基底物的特异性没有显著差异。然而，随着α-萘基底物的碳链长度从丙酸盐增加到辛酸盐，活性有降低的趋势。烟草天蛾的JHE已结晶，晶体特性表明将获得高分辨率结构。
