上海市规模化猪场猪流感的血清学调查

采用HI和EHSA方法，于1999—2002年间对上海市规模化猪场猪群进行了猪流感的血清学调查，通过对猪血清HI、ELISA试验的同步检测，表明本市规模化猪场猪血清仅对流感病毒的H3、H1亚型易感，能产生特异性血凝抑制现象或显色反应，表明存有针对H3、H1亚型流感病毒的血清抗体，阳性率31．8％至94．9％不等，而且种猪的阳性率及抗体滴度明显高于肉猪和保育猪。     

白芨中性杂多糖的分离纯化与结构分析

以白芨(Bletilla striata (Thunb.) Reichb.f.)块茎为材料,经热水抽提,乙醇沉淀,Sevag法脱蛋白,阴离子交换纤维素柱(DE-52)层析和凝胶柱(Sephadex G-100)层析,分离纯化得一白芨中性多糖.经高效凝胶渗透色谱(GPC)和凝胶柱层析(Sephadex G-100)鉴定为均一组分.GPC法测得其重均分子量约为99.658 ku.薄层层析、红外吸收光谱(FT-IR)、13C核磁共振谱(13C-NMR)和1H核磁共振谱(1H-NMR)分析该多糖为一中性杂多糖,由β-1,4-甘露糖(β-1,4-Man),β-1,4-葡萄糖(β-1,4-Glu)和α-1,6-葡萄糖(α-1,6-Glu)残基组成,三者的的摩尔比约为6.8∶3.2∶1.5.     

脱毛碱性蛋白酶的纯化及其生化特性研究

采用CM-阳离子交换层析和凝胶过滤层析分离碱性蛋白酶,得到了碱性蛋白酶的单一组分。对枯草芽孢杆菌(Bacillus subtilis)碱性蛋白酶SDS-聚丙烯酰胺电泳进行了分析。结果表明：其亚基分子量约为28kD,等电点约为8．4。并对其生化特性质进行研究,结果表明：酶活最适温度为45℃,最适pH值为10．5,在0．5mol／L的Na^ 对酶活有较大的促进作用。     

Rice spikelet rot disease in China - 1. Characterization of fungi associated with the disease

Rice spikelet rot disease (SRD) is an emerging disease of rice panicle in China, which affects both rice yield and grain quality. Four fungal pathogens were isolated from diseased rice grains. Morphological observation, biological testing and molecular characterization led to identify these fungi as Fusarium proliferatum, Bipolaris australiensis, Curvularia lunata and Alternaria tenuis. The four fungi can grow from 10 °C to 40 °C, and from pH 5 to pH 10. The most suitable temperature range is 25 °C-30 °C, however the optimal pH for sporulation of these fungi varies greatly. The four fungi can grow on media supplemented with different carbon and nitrogen sources. These differences in carbon and nitrogen requirements suggest differences in trophism, and have large effects on hyphal growth and spore production. The results suggest that rice SRD is caused by various fungi with diverse physiological characteristics.     

花生iso-ARah3基因克隆及多克隆抗体制备

类花生致敏原3(iso-ARah3)是花生致敏原3的同系物,其表达活性与干旱及黄曲霉侵染相关。本研究通过RT-PCR技术从花生种子cDNA文库中克隆获得iso-ARah3的开放阅读框(ORF),全长1533bp,编码510个氨基酸,N端预测有20个氨基酸的信号肽序列。通过序列比对发现,该克隆序列有1处缺失突变,其N端210个氨基酸序列与胰蛋白酶抑制因子的同源性较高,达83.60%。通过构建原核表达载体pET28a-isoARah3,转化进大肠杆菌BL21,经IPTG诱导表达,利用SDS-PAGE检测表明,融合蛋白His-isoARah3获得高效表达,分子量约54kD。His-isoARah3经纯化和富集,对新西兰兔进行4次免疫,纯化获得的iso-ARah3多克隆抗血清,通过间接ELISA检测,表明获得了效价比(1∶512000)很好的抗体。通过对融合蛋白的诱导前和纯化后样品进行Western Blot分析,结果显示仅在纯化样品相应位置(54kD)有明显信号,表明所制备的抗体具有很高灵敏度和特异性。本研究结果为深入研究花生iso-ARah3基因的功能奠定了基础。     

黄腹角雉源乳酸菌的筛选与特性研究

为寻求珍禽源优良的益生菌株,经分离培养、初筛和复筛试验,成功筛选出1株黄腹角雉源乳酸菌,并对其理化特性和安全性进行了研究,初步得出,该菌株能适应动物的胃肠道环境且安全无毒。     

单克隆抗体酶联免疫技术检测对虾皮下及造血组织坏死病的病原及其传播途径

用单克隆抗体ＥＬＩＳＡ技术对１９９４年５月～７月自山东和辽宁采集的虾池和海区材料，包括对虾、浮游生物、小型甲壳类生物、鱼类、底泥及饲料等共１９２个样品进行了对虾暴发性流行病病原ＨＨＮＢＶ的检测。结果表明，对虾中的ＨＨＮＢＶ阳性与虾池发病情况基本相符，用单抗ＥＬＩＳＡ方法可提前２０～４０ｄ对虾池的发病可能性作出预报；桡足类浮游生物的带毒率高于对虾，且其阳性的出现早于对虾，沿岸海区的桡足类浮游生物有较高的阳性率，它可能是对虾暴发性流行病的主要病原携带者；部分地区的卤虫也带有ＨＨＮＢＶ，同时还从糠虾等小型甲壳类生物中检出了病原。     

赤点石斑鱼神经坏死病毒主衣壳重组蛋白多克隆抗体的制备

把赤点石斑鱼（Epinephelus akaara）神经坏死病毒（RGNNV）主衣壳蛋白（MCP）基因的重组表达质粒载体pRSETA-MCP转化至大肠杆菌（Estherichia coli）BL21（DE3）,经IPTG诱导表达,SDS-PAGE显示表达的重组蛋白主要以不可溶的包涵体形式存在,分子量约44.5kD。通过Ni-NTA-Agarose亲和层析柱纯化,经分析纯度达90%,之后免疫新西兰兔制备抗血清,ELISA效价达1：12800以上。Western-blot分析结果显示,该血清与表达的重组蛋白有较强反应,说明通过原核表达的重组蛋白具有良好的免疫原性。     

病毒性出血性败血症病毒单链抗体的原核表达及其功能鉴定

为制备病毒性出血性败血症病毒(VHSV)单链抗体(single chain variable fragment antibody,ScFv)并鉴定其生物学功能,本研究提取抗VHSV单抗1G5的杂交瘤细胞株总RNA并反转录获得cDNA模板,通过PCR扩增VHSV抗体的轻链可变区(VL)和重链可变区(VH)编码序列,将其拼接成单链抗体Sc Fv基因后插入载体pET28a中,构建原核表达重组质粒并在大肠杆菌中诱导表达。结果表明,单链抗体主要以可溶性形式表达,分子量约28 ku,能特异性识别VHSV病毒的G蛋白并对VHSV病毒具有体外中和活性,其对VHSV病毒的G蛋白亲和力(KD)达到1.4×10~(–8) M。单链抗体ScFv的制备为进一步研究VHSV的治疗性抗体、快速诊断试剂奠定了基础。     

Extraction and Physicochemical Characterization of Pepsin Soluble Collagens from Golden Pompano (Trachinotus blochii) Skin and Bone

Pepsin-soluble collagen (PSC) was extracted and purified from wasted skin and bone of the golden pompano by acetic acid-pepsin method. The result showed that the PSCs extraction yields of skin and bone were 21.81% and 1.25% (wet weight), 62.21% and 1.78% (on the basis of lyophilized dry weight), respectively. Golden pompano skin and bone PSCs contained the typical chain of α and β dimers, and they were preliminarily judged to belong to type I collagen. The skin PSC had similar amino acid composition to bone PSC, which is rich in glycine, alanine, proline, and hydroxyproline. After addressing the pepsin, three helical structure of PSCs were intact, and their natural structures largely remained. The denaturation temperatures of skin and bone PSCs were 37.04°C and 38.23°C, respectively. Solubility results showed that the skin and bone PSCs solubility was the largest at pH = 3. The solubility of skin and bone PSCs was stable at NaCl concentrations lower than 3%. In addition, two PSCs in acid and low salt conditions had good solubility. This study demonstrated that golden pompano skin and bone could be used as good materials to extract PSC, representing an economic benefit and added value.

Abbreviations: SDS-PAGE: Sodium dodecyl sulfate polyacrylamide gel electrophoresis; FTIR: Fourier transform infrared; DSC: Differential scanning calorimetry; XRD: X-ray diffraction