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为了提高口岸和基层实验室检疫和监测玉米细菌性枯萎病菌的准确性和工作效率,利用环介导恒温扩增技术(LAMP),根据内切葡聚糖酶(EGase)基因前导序列,设计2个内引物和2个外引物,对玉米细菌性枯萎病菌进行快速检测。结果表明,使用玉米细菌性枯萎病菌的近缘种或引致相似症状的病原菌菊欧文氏菌玉米致病变种Erwinia chrysanthemi pv.zeae、玉米内州萎蔫病菌Clavibacter michiganensis subsp.nebraskensis、燕麦假单胞菌Pseudomonas avenae、杓兰欧文氏菌Erwinia cypripedii检测其特异性,仅玉米细菌性枯萎病菌有扩增。LAMP检测灵敏度达到2 pg DNA,为普通PCR的100倍;与其它检测方法相比,LAMP方法检测时间短,效率高,不仅降低了设备投入,易于操作,而且具有较高的灵敏度和特异性,适合玉米细菌性枯萎病菌的现场检疫和大规模检测。 相似文献
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光肩星天牛纤维素酶的性质研究 总被引：3，自引：0，他引：3
该文对光肩星天牛 (Anoplophoraglabripennis)幼虫纤维素酶的特性进行了研究 .内切 β 1,4 葡聚糖酶 (内切葡聚糖酶 ,Cx)和β 1,4 葡萄糖苷酶 (β 葡萄糖苷酶 )的最适作用温度均为 4 0℃ ,最适作用pH值分别为 4 4 5 6和 4 8,内切葡聚糖酶具有较广泛的pH值和温度作用范围 ,在 2 5 5 0℃之间能保持80 %以上活性 ,pH 3 2 7 2之间能保持 6 0 %以上的酶活性 .内切葡聚糖酶的热稳定性也稍强于 β 葡萄糖苷酶 ,但在 6 0℃温育 30min后 ,二者均丧失活性 .用含 0 1%CMC的聚丙烯酰胺凝胶电泳方法检测到光肩星天牛的内切葡聚糖酶具有两种同工酶 ,从非变性聚丙烯酰胺凝胶中回收该两条酶带 ,并在SDS 聚丙烯酰胺凝胶电泳中呈单一酶带 ,分子量分别为 2 6kD和 39kD .纯化的同工酶处于进一步研究中 相似文献
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巨大芽孢杆菌内切葡聚糖酶编码基因的克隆及序列分析 总被引：2，自引：0，他引：2
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Shuhei Takizawa Ryoki Asano Yasuhiro Fukuda Yasunori Baba Chika Tada Yutaka Nakai 《Animal Science Journal》2021,92(1):e13653
Rumen microorganisms produce various fibrolytic enzymes and degrade lignocellulosic materials into nutrient sources for ruminants; therefore, the characterization of fibrolytic enzymes contributing to the polysaccharide degradation in the rumen microbiota is important for efficient animal production. This study characterized the fibrolytic isozyme activities of a rumen microbiota from four groups of housed cattle (1, breeding Japanese Black; 2, feedlot Japanese Black; 3, lactating Holstein Friesian; 4, dry Holstein Friesian). Rumen fluids in all cattle groups showed similar concentrations of total volatile fatty acids and reducing sugars, whereas acetic acid contents and pH were different among them. Predominant genera were commonly detected in all cattle, although the bacterial compositions were different among cattle groups. Zymograms of whole proteins in rumen fluids showed endoglucanase activities at 55 and 57 kDa and xylanase activity at 44 kDa in all cattle. Meanwhile, several fibrolytic isozyme activities differed among cattle groups and individuals. Treponema, Succinivibrio, Anaeroplasma, Succiniclasticum, Ruminococcus, and Butyrivibrio showed positive correlations with fibrolytic isozyme activities. Further, endoglucanase activity at 68 kDa was positively correlated with pH. This study suggests the characteristics of fibrolytic isozyme activities and their correlations with the rumen microbiota. 相似文献
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The reactions of exo-cellulase （cellobiohydrolase, CBH） and endo-cellulase （endoglucanase, EG） were investigated by analyzing the insoluble residues of microcrystalline cellulose （MCC） and filter paper... 相似文献
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The diversity of 40 strains of Ralstonia solanacearum causing bacterial wilt of potato in the major potato-growing areas of Iran was assessed. Based on rep-PCR genomic fingerprinting, strains fell into two distinct groups. The first group contained 37 of the 40 strains and the second consisted of three strains from a narrow tropical region in Iran. The three strains from the narrow tropical region were found to be phenotypically and genotypically most similar to R. solanacearum biovar 2T strains, whereas all other strains were phenotypically and genotypically identified as being R. solanacearum biovar 2/race 3. Phylogenetic analysis of endoglucanase gene sequence information of two of the strains from the tropical region revealed that they belonged to phylotype II of the R. solanacearum species complex and had 100% sequence similarity to a biovar 2T strain from potato in Peru. This is the first report of the presence of R. solanacearum phylotype II/biovar 2T in Iran and the first report of the existence of this group of R. solanacearum outside South America. 相似文献
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以高效纤维素分解菌桔青霉(Penicillium citrinum)CR-2菌株为材料,利用分子筛及离子交换技术纯化分离其内切葡聚糖酶蛋白,首次获得了电泳纯的桔青霉内切葡聚糖酶蛋白组分,大小为27.26 kDa,最适作用温度为60℃,最适作用pH为5。对研究桔青霉纤维素酶降解纤维素的作用机理以及该菌株的改造应用具有重要意义。 相似文献
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考察发酵培养基组分对纤维杆菌X4-9发酵产葡聚糖内切酶、葡聚糖外切酶和β-葡萄糖苷酶的影响。应用DPS软件的二次回归旋转中心组合实验设计方法,对纤维杆菌X4-9的发酵培养基（花生秸杆粉、蔗糖、尿素、(NH4)2SO4、硫酸镁、磷酸二氢钾）进行了优化。结果表明：在试验数值范围内,花生秸杆粉、蔗糖和(NH4)2SO4对酶活均会产生极显著的正效应,而尿素、硫酸镁和磷酸二氢钾的用量则具有明显的负效应;在优化的发酵培养基配方（花生秸杆粉30 g/L、蔗糖20 g/L、尿素2.5 g/L、(NH4)2SO4 10 g/L）下,葡萄糖内切酶、葡聚糖外切酶和β-葡萄糖苷酶的酶活分别达到2.705163,5.723014和3.614921 I U/mL,比初始发酵培养基配方下的各酶活分别提高了123.66%,146.32%和186.40%。纤维杆菌X4-9均能同时产生葡萄糖内切酶、葡聚糖外切酶、β-葡萄糖苷酶等纤维素降解复合酶系,且这些酶高产的培养基条件较为一致。 相似文献
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芒果炭疽病（Colletotrichum gloeosporioides）是为害芒果的重要病害之一,为了明确内切葡聚糖酶CgEg1B与芒果炭疽病菌致病力的关系,本实验以芒果炭疽病菌DNA为模板,利用同源克隆技术扩增CgEg1B,对其序列特征、蛋白的保守结构域进行分析,并借助In-Fusion?HD Cloning Kit技术进行敲除载体构建。结果表明,该基因DNA和cDNA全长分别为1077 bp、1020bp,编码区有1个内含子（大小为57bp）,推测编码339个氨基酸,其分子量约为37.13 kDa,等电点PI为5.11。与NCBI网站中已公布的基因进行Blastp比对,发现该序列与鳄梨炭疽菌（C.gloeosporioides）（EQB54542.1）的内切葡聚糖酶基因相似性均为99%;该基因的敲除载体pCgEg1BGH-1构建成功。CgEg1B基因具备真菌内切葡聚糖酶基因家族的序列特征,推测CgEg1B基因可能与芒果炭疽病菌的侵入、定植和致病性有关。 相似文献