核型多角体病毒的增值与棉铃虫血淋巴酯酶的变化

核型多角体病毒（NPV）对同源棉铃虫有很强的毒杀作用,是重要杀虫资源。病毒感染导致宿主代谢紊乱,引起一系列生化反应的变化,可通过一定方法观察到其表征,此为病毒感染的病理生化特征。昆虫血淋巴对于病毒感染引起的全身症状具有重要作用,并影响宿主物质和能量代谢的性质与水平,反映出病毒一宿主的互作关系。本文以血淋巴酯酶同工酶（EST）为感病指标,对其感染变化进行研究。1材料和方法11材料11．呈供试病毒棉铃虫核型多用体病毒．取自湖北仙桃磷肥厂生化分厂。1．1．2供试昆虫棉铃虫三龄幼虫,由该厂提供,半人工饲料饲养。豆…     

淡足侧沟茧蜂寄生对甜菜夜蛾幼虫血淋巴总糖、蛋白质及虫体脂质含量的影响

为探讨淡足侧沟茧蜂Microplitis pallidipes Szepligeti调控寄主的生理机制,测定了淡足侧沟茧蜂寄生后,甜菜夜蛾Spodoptera exigua(Hübner)幼虫血淋巴总糖、蛋白质及虫体脂类含量的变化。研究结果表明,寄生后连续5 d的观察时间内,甜菜夜蛾幼虫血淋巴总糖含量从寄生后第1天开始就高于未寄生寄主幼虫,且在寄生后第2至5天达到显著水平;除寄生后第3天外,被寄生寄主幼虫血淋巴总蛋白质含量始终低于未寄生幼虫,且在寄生后第1、4、5天达到显著水平;甜菜夜蛾被寄生后,虫体脂质含量始终高于未寄生幼虫,且从寄生后第2天开始达到显著水平。本研究揭示,淡足侧沟茧蜂寄生刺激了寄主甜菜夜蛾幼虫血淋巴总糖合成,但抑制了其蛋白质合成,同时也刺激了甜菜夜蛾虫体脂质合成。     

利用杆状病毒表达系统表达金鱼生长激素I基因

以不含起始密码ATG的质粒Psxivvi⁺X3为转移载体,将编码金鱼生长激素I的Cdna插入粉纹夜蛾核型多角体病毒(TnNPV)基因组中,构建了形成多角体的重组病毒株TnNPV—SX⁺gfGHl21a。该毒株能利用合成多角体XIV串联启动子,在重组病毒感染的草地贪夜蛾(Spodoptera frugiperda,Sf)昆虫细胞及银纹夜蛾幼虫中表达金鱼生长激素I基因。感染离体细胞及虫俸后的蛋白SDS聚丙烯酰胺凝胶电泳表明．所表达的蛋白分子量为22．5kDa,与理论计算值相符。Westem印迹证实。金鱼生长激素特异蛋白得到表达。     

甜菜夜蛾体内代谢耐受性对转Bt基因棉响应的时间动态

在室内用转Bt基因棉和亲本常规棉饲养甜菜夜蛾（Spodoptera exigua Hübner）幼虫,测定了不同取食时间后甜菜夜蛾4龄幼虫体内营养物质含量和消化酶、保护酶、解毒酶活力的变化．结果表明,分别取食Bt棉和常规棉,甜菜夜蛾幼虫体内的营养物质含量和消化酶、保护酶、解毒酶活力差异显著．与取食常规棉相应时间的个体相比,取食Bt棉1,6,24h后,幼虫体内的游离脂肪酸和葡萄糖含量显著提高;取食Bt棉1,4,6,24h后,幼虫体内胰蛋白酶和总超氧化物歧化酶的活力显著增高,脂肪酶、羧酸酯酶和乙酰胆碱酯酶活力则显著降低．取食相同品种棉花,幼虫体内营养物质含量和消化酶、保护酶、解毒酶活力受甜菜夜蛾危害时间的显著影响．取食Bt棉24h的幼虫,其体内游离脂肪酸和总氨基酸含量显著低于取食1h的个体;脂肪酶和胰蛋白酶活力显著低于取食1和4h的个体,但羧酸酯酶和乙酰胆碱酯酶酶活力显著高于取食1,4,6h的个体．棉花品种和甜菜夜蛾为害时间的交互作用可显著影响甜菜夜蛾体内脂肪酶、胰蛋白酶、乙酰胆碱酯酶和总超氧化物歧化酶的活力．通过测定甜菜夜蛾体内保护酶和解毒酶活力对Bt棉响应的时间动态,对于评价植食性昆虫在毒素蛋白持续选择压力下的生理反应和抗性变化具有重要参考意义．     

三种夜蛾科昆虫核型多角体病毒DNA相关性的研究

核型多角体病毒属杆状病毒科,主要感染鳞翅目、双翅目和膜翅目的昆虫,具有90～160kb长的双链,超螺旋DNA基因组。现已发现约500种核型多角体病毒,这些病毒之间有什么关系？它们的亲缘关系如何？我们以甘兰夜蛾核型多角体病毒（简称MbNPV）、甜菜夜蛾核型多角体病毒（简称SeNPV）和斜纹夜蛾核型多角体病毒（简称SINPV）为材料,用限制性内切酪和分子杂交技术对它们的基因组DNA进行比较研究,并对其中一种病毒MbMV多角体蛋白基因进行了定位,现将结果报道如下;材料和方法1材料甜菜夜蛾和斜纹夜蛾健康幼虫,病毒麦种MbNPV、SeN…     

烟青虫核型多角体病毒的复制和染病后血淋巴蛋白的变化

用烟青虫(Hiliothis assulta)核型多角体病毒感染5龄初烟青虫幼虫,以染病后24、48·,72、96/120小时分别测定了虫体血淋巴蛋白浓度的变化。幼虫染病后24小时血淋巴蛋白浓度要高于同期对照组,72小时后染病幼虫血淋巴蛋白浓度较对照急剧下降。在染病及对照血淋巴样品中电泳分析(PAGE)三种蛋白(普通蛋白、糖蛋白和脂蛋白)均可分别染出22条、3条和3条带。分析结果表明,在虫体正常生长代谢过程中发生变化的主要蛋白可能大多为糖脂复合蛋白,但病毒的侵染能抑制这些变化的产生。电镜观察染病毒后幼虫的中肠组织和气管上皮组织,发现中肠染病轻微,不形成多角体。气管上皮细胞感染情况表明其属于对NPV感染较为敏感的组织之一,并在虫体染病后的病毒二次感染上可能起着重要作用。     

饲养五种夜蛾科昆虫的一种简易人工饲料

以黄豆粉、酵母粉及麦麸粉等为主要营养成分 ,研制和筛选出了一种既可工厂化饲养斜纹夜蛾幼虫 ,又可大量饲养甜菜夜蛾、银纹夜蛾、粉纹夜蛾和棉铃虫幼虫的简易人工半合成饲料。利用该饲料目前已实现了工厂化饲养斜纹夜蛾幼虫增殖斜纹夜蛾核多角体病毒     

用核型多角体病毒防治大豆银纹夜蛾

银纹夜蛾(Plusia agnata Staudinger)是大豆主要食叶害虫,严重发生时对大豆产量影响很大。我们从1979年6月起,从自然息病死亡的银纹夜蛾虫体中分离到一种多角体病毒,并对其形态特征和杀虫效果进行了研究,现报道如下。     

淡足侧沟茧蜂寄生对草地贪夜蛾幼虫血淋巴黑化反应及酚氧化酶的影响

【目的】明确淡足侧沟茧蜂Microplitis pallidipes寄生对草地贪夜蛾Spodoptera frugiperda血淋巴黑化率、酚氧化酶原（Prophenoloxidase,PPO）基因表达量和酚氧化酶（Phenoloxidase,PO）活性的影响,为更有效的利用淡足侧沟茧蜂防控草地贪夜蛾提供理论依据。【方法】通过室内寄生实验确定草地贪夜蛾被淡足侧沟茧蜂寄生的最佳龄期;通过RT-qPCR分析草地贪夜蛾两个PPO基因（SfPPO1和SfPPO2）的时空表达谱;通过薄膜法统计草地贪夜蛾被寄生后的血淋巴黑化率;采用吸光光度法测定草地贪夜蛾被寄生后的血淋巴PO活性;采用RT-qPCR测定草地贪夜蛾被寄生后血淋巴SfPPO1和SfPPO2的相对基因表达量。【结果】草地贪夜蛾被淡足侧沟茧蜂寄生的最佳龄期为3龄幼虫,SfPPO1和SfPPO2均在卵块和4龄幼虫中基因表达量较高,且主要在幼虫血淋巴中表达。草地贪夜蛾被寄生后12、24、48和72 h的血淋巴黑化率显著低于未寄生组（P<0.05）,SfPPO1和SfPPO2的相对基因表达量和PO活性也低于未寄生组。相关关系分析表明,SfPPO1的相对基因表达量与SfPPO2的表达量呈现线性关系（R2=0.9124）,PO活性与两个PPO基因相对表达量之间、黑化率与PO活性和PPO基因相对表达量之间均呈现正相关。【结论】淡足侧沟茧蜂寄生会抑制草地贪夜蛾血淋巴的黑化率,下调血淋巴中酚氧化酶原基因的表达量和PO活性,且PO活性、PPO基因相对表达量及血淋巴黑化率3个指标之中,两两之间均呈现正相关性。     

云南莱氏野村菌田间自然发生流行动态研究

为了弄清楚莱氏野村菌田间自然发生流行规律,本研究于2012-2014年对云南省昆明市晋宁区花椰菜上莱氏野村菌的发生动态进行了调查研究,发现莱氏野村菌能感染银纹夜蛾Argyrogramma agnata和甜菜夜蛾Spodoptera exigua幼虫,二者的田间被感染症状相似。在昆明市晋宁区花椰菜田间,莱氏野村菌于每年7-10月份在银纹夜蛾和甜菜夜蛾幼虫种群中发生流行,其中9月份为发生流行高峰期,而银纹夜蛾幼虫的田间自然感染率高于甜菜夜蛾。2012-2014年7月、8月、9月、10月银纹夜蛾的平均感染率分别为34. 38%、62. 53%、78. 49%和33. 67%,甜菜夜蛾的平均感染率分别为8. 39%、8. 65%、24. 49%和3. 47%。该菌对同种害虫不同龄期幼虫的感染率不同,其中银纹夜蛾1-3龄幼虫的感染率高于4-5龄;而甜菜夜蛾4-5龄幼虫的感染率高于1-3龄。该研究将为莱氏野村菌开发利用及银纹夜蛾和甜菜夜蛾的生物防治研究提供依据。     

Diversity of plant cell wall esterases in thermophilic and thermotolerant fungi

Fourteen thermophilic and thermotolerant fungal strains isolated from composting soils produced plant cell wall-acting esterases in a medium containing corn cobs and oat spelt xylan. The concentrated and dialyzed protein extracts of these fungi were fractionated using isoelectric-focusing, gels sliced and eluted protein in each slice was assayed for esterase activity against p-nitrophenyl acetate. A total of 84 esterases detected on the basis of pI were found to show distinct preferential substrate specificities towards p-nitrophenyl acetate, p-nitrophenyl ferulate and p-nitrophenyl butyrate, and were putatively classified as acetyl esterases and esterases types I and II. None of the esterases were active against p-nitrophenyl myristate. In addition, these esterases were characterized as acid, neutral or alkaline active.     

The non-specific esterases of mouse lung

The non-specific esterases of the lung of the house mouse, M. musculus, were examined by polyacrylamide electrophoresis and by isoelectric focusing. At least 13 different esterases were distinguished and identified, mainly by their catalytic properties, susceptibility to inhibition, developmental patterns and phenotypic variation amongst different strains. A list of diagnostic features of the 13 esterases was presented. None of the esterases was lung-specific. However, the pattern of esterases found in the adult lung was characteristic of that organ. It was pointed out that this pattern is associated with the high degree of tissue differentiation in the adult lung. At least 8 esterases were found which belong to the isozyme system of carboxylesterase EC 3.1.1.1, under the control of genes located on chromosome 8. These esterases accounted for about 90% of the esterase activity in the lung.     

Characterization of esterases from Cucurbita pepo cv. "Eskandrani"

Two of the six esterases identified in Cucurbita pepo cv. "Eskandrani" were purified to homogeneity using two chromatography steps: anion exchange and gel filtration. The molecular weights of C. pepo esterases EIc and EII were 50,000 +/- 1500 and 68,000 +/- 1900 Da from gel filtration and 47,000 and 66,000 Da from SDS/PAGE, respectively, suggesting a monomeric structure for both enzymes. Esterases EIc and EII had K(m) values of 1.22 and 1.56 mM and pH optima at 9.0 and 8.0, respectively. The substrate specificity of C. pepo esterases EIc and EII were determined for a number of p-nitrophenyl esters, where their affinity toward these substrates were decreased as carbon atom number increased. Esterases EIc and EII had the same temperature optima, 40 degrees C. Thermal stability studies of esterases EIc and EII indicated that half maximal activities of EIc and EII esterases were reached at 55 degrees C and 50 degrees C, while they lost 45%, 51% and 70%, 77% of their activities after 30 and 90 min of incubation at 40 degrees C, respectively. The effect of different metal cations and inhibitors were examined. The inhibition studies revealed that the active sites of the two esterases contain serine and cysteine residues. The characteristics of C. pepo esterases are closely similar to those of microbial esterases used in food processing and food industry.     

BsNPV感染油桐尺蠖及Bs484细胞的酯酶分析

本文使用聚丙烯酰胺凝胶电泳及薄层扫描技术测定了油桐尺蠖Ｂｕｚｕｒａｓｕｐｐｒｅｓｓａｒｉａ和Ｂｓ４８４细胞感染核型多角体病毒后的酯酶（ＥＳＴ）含量及类型的变化。结果表明,油桐尺蠖中肠ＦＳＴ的含量和类型在病毒感染８小时后就有明显的改变,随着感染时间延长,这二项指标都有较大的变化。而Ｂｓ４８４细胞的ＥＳＴ含量变化开始于病毒感染后３小时,细胞ＥＳＴ的类型则无改变。     

Enzyme-coupled assay of acetylxylan esterases on monoacetylated 4-nitrophenyl beta-D-xylopyranosides

Three different monoacetates of 4-nitrophenyl beta-D-xylopyranoside were tested as substrates for beta-xylosidase and for microbial carbohydrate esterases and a series of non-hemicellulolytic esterases. The acetyl group in 2-O-acetyl, 3-O-acetyl, and 4-O-acetyl 4-nitrophenyl beta-D-xylopyranoside makes the glycoside resistant to the action of beta-xylosidase (EC 3.2.1.37). This fact was explored to introduce a new enzyme-coupled assay of acetylxylan esterases (EC 3.1.1.72) and other carbohydrate-deacetylating enzymes. The deacetylation converts the monoacetates into the substrate of beta-xylosidase, the auxiliary enzyme. The effect of the acetyl group migration along the xylopyranoid ring in aqueous media can be avoided by shortening the assay duration. The assay enables an easy examination of the positional specificity of the enzymes, which is important for classification of acetylxylan esterases and for elucidation of the structure-function relationship among carbohydrate esterases in general. Non-hemicellulolytic esterases showed different positional specificity of deacetylation than did acetylxylan esterases.     

Change in the tissue spectrum of carboxylic ester esterases in the postnatal period in rats

A comparative investigation of the composition of electrophoretic fractions of esterases of compound ethers of carbonic acids has been carried out in the rat tissues. Carboxyl, aryl, acetyl and choline esterases were identified by the sensitivity to inhibitors. Changes in the composition of these esterases during the postnatal period were followed.     

Monocyte nonspecific esterase. Enzymologic characterization of a neutral serine esterase associated with myeloid cells

Monocytes contain a characteristic, prominent set of membrane-bound nonspecific esterases with a slightly acid isoelectric point. These esterases are also detected at modest levels in some granulocyte preparations. They are not apparent in lymphocytes. Among 18 fresh myeloid leukemias and myeloid leukemia cell lines, those of subtypes M4 (myelomonocytic) and M5 (monocytic) were strongly positive; some of subtypes M1-M3 (granulocytic) were moderately positive. The esterases were not detected among 32 fresh lymphoid leukemias and lymphoid leukemia and lymphoblast cell lines. The membrane-bound monocyte esterases, solubilized by treatment of monocyte preparations with nonionic detergent, were resolved by ion-exchange chromatography. The monocyte species account for 80-95% of the total nonspecific esterase activity of monocytes. The resolved enzymes behave as neutral serine carboxyl esterases and are highly sensitive to inhibition by diisopropylfluorophosphate (DFP) and also by sodium fluoride. Similar analysis of a lymphocyte preparation yielded no detectable monocyte esterases, but yielded numerous other forms which were generally resistant to inhibition by DFP and NaF. These nonspecific esterases are also present at background levels in monocytes. The resolution and characterization of the membrane-bound serine esterases from monocytes demonstrates the basis for the well-known cytochemistry of monocytes. The results are also crucial to the development of an immunologic surface marker test for myeloid cells and the study of monocyte membrane physiology.     

两株蓖麻蚕核型多角体病毒DNA同源性的研究

两株不同来源的蓖麻蚕核型多角体病毒(ArscsNPV和ArNPV)经提纯后,使用SDS—苯酚抽提病毒核酸,并使用限制性内切酶EcoRI,BamHI酶解后,用分子杂交方法与缺口平移标记的ArscsNPV-DNA探针杂交,分析了两株蓖麻蚕NPV病毒核酸的同源性。EcoRI酶解的ArNPV-DNA产生8个片段,其中5个片段能与ArscsNPV-DNA探针杂交。BamHI酶解ArNPV-DNA产生7个片段,其中6个片段能与ArscsNPV-DNA探针杂交。结果表明:两株蓖麻蚕NPV之间病毒核酸具有很高的同源性。使用斑点杂交方法分析了ArscsNPV与ArNPV,柞蚕NPV及家蚕NPV之间的核酸同源性,结果表明:ArscsNPV与ArNPV,柞蚕NPV具有同源性。而与家蚕NPV无核酸同源性。     

Aspergillus niger I-1472 and Pycnoporus cinnabarinus MUCL39533, selected for the biotransformation of ferulic acid to vanillin, are also able to produce cell wall polysaccharide-degrading enzymes and feruloyl esterases

The filamentous fungal strains Aspergillus niger I-1472 and Pycnoporus cinnabarinus MUCL39533, previously selected for the bioconversion of ferulic acid to vanillic acid and vanillin respectively, were grown on sugar beet pulp. A large spectrum of polysaccharide-degrading enzymes was produced by A. niger and very few levels of feruloyl esterases were found. In contrast, P. cinnabarinus culture filtrate contained low amount of polysaccharide-degrading enzymes and no feruloyl esterases. In order to enhance feruloyl esterases in A. niger cultures, feruloylated oligosaccharide-rich fractions were prepared from sugar beet pulp or cereal bran and used as carbon sources. Number of polysaccharide-degrading enzymes were induced. Feruloyl esterases were much higher in maize bran-based medium than in sugar beet pulp-based medium, demonstrating the ability of carbon sources originating from maize to induce the synthesis of feruloyl esterases. Thus, A. niger I-1472 could be interesting to release ferulic acid from sugar beet pulp or maize bran.