海带和条斑紫菜凝集素提取液对刺参体壁主要免疫酶活性的影响

为探讨凝集素提取液对刺参Apostichopus japonicus免疫的影响,将刺参基础饲料中分别添加质量分数为0·64%、1·28%、2·56%的海带凝集素提取液,或质量分数为1·88%、3·76%、7·52%的条斑紫菜凝集素提取液,分别投喂6个试验组刺参(体质量为3·50 g ±1·95 g),以基础饲料饲养组为对照,分别于投喂凝集素提取液后第4、8、12、17天时,检测各组刺参体壁中过氧化氢酶( CAT)、溶菌酶( LSZ)、碱性磷酸酶(AKP)和酸性磷酸酶(ACP)的活性。结果表明：投喂海带凝集素提取液后,各浓度组刺参CAT、 LSZ活性在第8、12、17天时均有显著或极显著提高(P<0·05或P<0·01),0·64%组ACP活性在第8、17天时有显著提高(P<0·05);投喂条斑紫菜凝集素提取液后,各浓度组刺参CAT活性在第8、12、17天时有显著或极显著提高( P<0·05或P<0·01),7·52%组LSZ活性在第8天时有显著提高( P<0·05), AKP活性在第4、17天时有极显著提高( P<0·01), ACP活性在第12天时7·52%组有极显著提高( P<0·01),第17天时各浓度组均有显著或极显著提高(P<0·05或P<0·01)。研究表明,海带和条斑紫菜凝集素提取液均能提高剌参体壁中CAT、 LSZ、 AKP、 ACP的活性,显著增强剌参非特异性免疫水平,将其作为刺参免疫增强剂具有广阔的应用前景。     

Structure and possible function of <Emphasis Type="Italic">N</Emphasis>-glycans of an invertebrate C-type lectin from the acorn barnacle <Emphasis Type="Italic">megabalanus rosa</Emphasis>

ABSTRACT:   A C-type lectin (BRA-2) isolated from the acorn barnacle Megabalanus rosa , which was a glycoprotein having an N -linked sugar chain, was deglycosylated by N -glycopeptidase F. The structure of the released sugar chains was determined by a 2-D mapping method after derivatization with a fluorescent reagent, 2-aminopyridine, to be Manα1-6(Manα1-3)Manβ1-4GlcNAcβ1-4(Fucα1-6)GlcNAc and Manα1-6(GlcNAcβ1-2Manα1-3)Manβ1-4GlcNAcβ1-4(Fucα1-6)GlcNAc. The structures were confirmed by matrix-assisted laser desorption ionization mass spectrometry and a comparison with authentic sugar chains by high-pressure liquid chromatography. Various properties of BRA-2 were examined before and after deglycosylation. The susceptibility of BRA-2 to protease digestion was increased by deglycosylation. However, the inhibitory activity toward calcium carbonate crystallization as well as the hemagglutinating activity of deglycosylated BRA-2 was significantly decreased. These results suggest that the sugar chains of BRA-2 are important to both its structural stability and its function.     

植物凝集素SMLII 基因启动子的克隆及序列分析

根据已克隆的丹参植物凝集素SMLII基因cDNA序列,利用染色体步移技术克隆出SMLII 启动子区序列,并进行生物信息学预测分析该基因的功能,结果得到了该基因上游1023 bp的启动子序列（GenBank AccessionNo: KF193867）。分析表明,在该序列中不但含有真核生物典型的核心启动子区TATA-box、CAAT-box,而且含有一些特有的上游启动子元件ABRE、ARE、ASF1MOTIFCAMV、HSE、IBOXCORE、WBOXATNPR1等重要的顺式调控元件及一些光反应相关元件。     

鱼类凝集素概述

鱼类凝集素成员种类繁多、功能多样,是鱼体免疫系统的重要组成部分。随着生物技术的发展,人们不断从鱼体内分离出多种具有生物活性的凝集素,对鱼类凝集素的研究逐年增多。以鱼类凝集素为研究对象,结合国内外研究成果,对鱼类凝集素的分类及功能等进行阐述,以期为今后的研究及应用提供一定的参考。     

Variation in Relative Amounts of Isolectins in Bread Wheat (Triticum aestivum) Landraces from Northern Nigeria and Chad

Wheat germ agglutin (WGA) present in the embryo of a bread wheat grain is a mixture of three isolectins, viz CL_A, CL_B and CL_D which are coded by genes located on die chromosomes 1A, 1B and 1D. Their respective absolute amounts were determined in 62 Nigerian and five Chad landraces. Added was the Madagascar variety ‘Kanem’ which is stated to be selected from Chad material. Some of the Nigerian landraces were formerly identified as derived from Indian Pakistani wheat varieties/landraces introduced into Northern Nigeria before 1940. These had relatively high CL_D/GL_A and CL_B/CL_A ratios. Other Nigerian landraces with such high ratios were postulated to come from India/Pakistan, too. The Chad wheats, except ‘Kanem’, have WGA amounts and-ratios similar to those native to Northern Nigeria. This may point to a common history. ‘Kanem’ is said to be bred in Madagascar from Chad wheats. Apparently it has a different origin. So the determination of the WGA amount and its isolectin composition is a helpful means to identify the history of a land race or of an improved variety.     

Insect peptide hormones: a selective review of their physiology and potential application for pest control

Our knowledge on primary structure, synthesis, release, receptor binding, structure-activity relationships, mode of action and degradation of, mainly, neuropeptides from insects has increased dramatically during the last 10 years or so. Here, five case studies are presented, which deal selectively with effects on: reproduction (trypsin modulating oostatic factor in mosquito); energy metabolism, locomotion and the immune system (adipokinetic hormones); water and ion balance, and feeding behaviour (diuretic hormones, kinins, sulfakinins); sex attraction (pheromone biosynthesis activating neuropeptide); and growth and development, and muscle activity (allatostatins). The literature is reviewed in the context of how the knowledge on neuropeptides has been and can be used for the design of novel, safe and selective compounds to control pest insects in the foreseeable future.     

串珠镰刀菌孢子表面的一种凝集素

 用0.2% SDS磷酸缓冲液从串珠镰刀菌(Fusarium moniliforme)孢子表面抽提蛋白质。孢子表面蛋白经DEAE-Sepharose阴离子交换柱层析和Sephacryl S-100分子筛柱层析,分离和纯化了一种凝集素。该凝集素的分子量为70 kDa,糖含量为19.8%,对兔血红细胞有很强的凝集活性,凝集活性被半乳糖特异性地抑制。EDTA和一些金属离子不影响凝集活性。     

几种植物抗虫基因研究进展

概述了目前应用于植物抗虫基因工程的苏云金杆菌毒蛋白基因、蛋白酶抑制剂基因和植物凝集素等三类主要基因的分类、杀虫机理及应用现状;探讨了植物抗虫基因工程中存在的问题和解决方案;     

菲律宾蛤仔凝集素的分离纯化及抑菌活性研究

采用Cellulose DE52离子交换层析、Sephadex G- 100分子筛层析及TSK G3000PWXL凝胶色谱柱HPLC从菲律宾蛤仔Ruditapes philippinarum中分离纯化出具有N-乙酰半乳糖酰胺(N- acetyl- D- galactosamine,GaINAc)和猪胃黏蛋白(Mucin from porcine stomach,PSM)特异性的菲律宾蛤仔凝集素(简称为MCL-T).SDS-PAGE分析结果表明,MCL-T的相对分子量为148000,含有62000和36000的亚基.抑菌试验结果表明,MCL-T对金黄色葡萄球菌Staphylococcus aureus和枯草芽孢杆菌Bacillus subtilis有较高的抑菌活性.对MCL-T中Trp残基、-S-S-、-SH以及Tyr残基进行化学修饰后,MCL-T对金黄色葡萄球菌的抑菌活性丧失;对其-S-S-进行化学修饰后,MCL-T对枯草芽孢杆菌的抑菌活性影响不大,而对其-SH、Trp残基和Tyr残基进行化学修饰后,MCL-T对枯草芽孢杆菌的抑菌活性丧失.研究表明,MCL-T 肽链上的氨基酸残基状态与其抑菌活性有关.