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桑粒肩天牛（ＡｐｒｉｏｎａｇｅｒｍａｒｉＨｏｐｅ）幼虫肠道内有完整的纤维素酶系，其中以内切－β－１，４－葡聚糖酶（Ｃｘ酶）活性最强、β－１，４－葡萄糖苷酶次之，外切－β－１，４－葡聚糖酶（Ｃ１酶）最弱、测定了Ｃｘ酶和β－１，４－葡萄糖苷酶的动力学特性以及金属离子对酶活性的影响。二者的最适作用ＰＨ值分别为４．４和５．６；最适作用温区分别为３０℃—４５℃和４５℃—５０℃；Ｃｘ酶经５０℃处理２ｈ酶活性仅下降１８．８％，而β－葡萄糖苷酶活性完全丧失。９种金属离子对纤维素酶都无明显激活作用，相反，除Ｈｇ＋＋和Ｐｂ＋＋对酶活性有强烈抑制作用外，Ｍｎ＋＋和Ｃｕ＋＋即使在０．００５ｍｏｌ／Ｌ低浓度下，对酶活性也有明显的抑制作用，这对今后开发酶抑制剂用于防治天牛等蛀干害虫，具有重要意义。
Apriona graminicola (AprionagermariHope) larvae have intact cellulases in the intestine, among which endo-β-1,4-glucanase (Cx enzyme) is the most active, and β-1,4-glucosidase Second, the exonuclease-β-1,4-glucanase (C1 enzyme) was the weakest. The kinetic properties of Cx and β-1,4-glucosidase and the effect of metal ions on the enzyme activity were determined. The optimal PH values for the two enzymes were 4.4 and 5.6, respectively. The optimal temperature range was 30 ℃ -45 ℃ and 45 ℃ -50 ℃, respectively. The enzyme activity of Cx enzyme treated with 50 ℃ for 2h decreased only by 18. 8%, and β-glucosidase activity completely lost. On the contrary, except for Hg ++ and Pb ++, which strongly inhibited the enzyme activity, Mn ++ and Cu ++ inhibited the enzyme activity even at a low concentration of 0.005mol / L Role, which is of great significance for the future development of enzyme inhibitors for the prevention and control of pests and other borers.