Expression of Aspergillus niger N5-5 in E. coli and purification and identification of products

Due to the feature of high hydrolysis, tannase is widely used in food, beverage, brewing and other fields. However, high cost in producing natural tannase makes it difficult to apply tannase to industry in a large-scale. Microbial expression systems can be used for preparing numerous amount of enzyme at low cost, so in this paper Aspergillus niger N5-5 was expressed using E. coli system. Specific primers were designed based on the Aspergillus niger N5-5 sequence N3 (GenBank, No.: KP677552), and tannase gene tan was promoted to carry 6 His tag and enzyme cutting site which contains NdeI/HindIII using PCR amplification. Then, tannase gene tan was connected to expression vector by NdeI/HindIII enzyme cutting. In this way, recombinant expression vector tan-pET43.1a was formed. Then, the expression vector pET43.1a by NdeI/HindIII enzyme cutting was transformed into E. coli BL21 (DE3) to induce expression of Aspergillus niger N5-5. When the induced fungi were disrupted by the ultrasonic wave, the crude enzyme was extracted and purified by using the IMAC, and then the activity of the crude enzyme and pure enzyme was determined. According to the results of determination of the tannase activity, the tannase activity of the crude enzyme was greatly improved after the crude enzyme was purified, and the specific activity of the pure enzyme was about 8 times of that of the crude enzyme. The results of SDS-PAGE of the pure enzyme showed that the molecular mass of the pure enzyme was about 65 kDa/64–65 kDa, which was consistent with the expected result (64.2 kDa), It can be concluded that the crude enzyme solution was purified successfully. The results of pure enzyme’s protein identification by Western Blotting showed that clear protein bands pro-3 were observed. Molecular mass of clear protein bands pro-3 was about 65 kDa, which was in line with the expected results (64.2 kDa). It can be seen that the aforementioned expression protein could be specifically combined with His tag. It proved expression protein to be a recombinant fusion protein with 6 His tag.     

Review of the New Caledonian species of Acritoptila Wells, 1982 (Trichoptera,Insecta), with descriptions of 3 new species

We review the New Caledonian representatives of the Australasian endemic hydroptiline genus Acritoptila, based on examination of a considerable collection of material in the Swedish Museum of Natural History and of types of previously established species. A key for identification of males is given and includes 3 species newly described here: A. parallela sp. n., A. forficata sp. n. and A. macrospina sp. n. For all New Caledonian species, male genitalia are illustrated, and for 5 associated females, distinctive features are illustrated and described.     

退化高寒草甸关键生态属性对多途径恢复措施的响应特征

高寒草甸是青藏高原的主体植被类型，但退化态势较为严峻，严重威胁青藏高原生态屏障的战略地位。退化高寒草甸的复健是世界性难题，治理效果也因退化状态、恢复措施及气候环境而异。以春季休牧、秋季休牧、畜群结构优化、减畜轮牧、围栏封育及翻耕改建等典型多途径恢复措施下的退化高寒草甸为对象，系统探讨主要生态要素和生态功能的响应特征及潜在过程。结果表明，典型恢复措施下退化高寒草甸的植被生产力、土壤有机碳密度及土壤饱和持水量等生态要素都得到一定程度的提升，而恢复效果与实施年限及恢复措施密切相关。围栏封育和翻耕改建下土壤有机碳密度及饱和持水量随恢复年限均表现为对数饱和型的响应特征，退化高寒草甸固碳持水功能的基本恢复年限约为6—10年。春季休牧、秋季休牧、畜群结构优化、减畜轮牧、围栏封育等放牧管理恢复措施应适用于轻度退化至重度退化的高寒草甸，而翻耕改建则是极度退化高寒草甸的适宜治理措施。由于多途径恢复措施的关注目标不同，今后研究应集中在恢复措施的组合优化和综合评价等方面。     

Succession in zooplankton and hydrophytes of a seasonal water on the west coast of South Africa

Paramesochra mielkei sp.n. is described and figured from the interstices of subtidal sandy sediments off the SW Dutch coast. Kunz' (1981) phylogenetic scheme of the Paramesochridae Lang, 1948 is re-examined and it is suggested that the family comprises two phyletic lines which originated early in paramesochrid evolution. Translation into Linnean hierarchies implies the establishment of two new sub-families. Within the primitive Diarthrodellinae subfam. n., Tisbisoma Bozic, 1964 is ancestral to Diarthrodella Klie, 1949 s.l. and Rossopsyllus Soyer, 1975. Remanea Klie, 1929 is transferred to the Paramesochrinae subfam. n. which comprises the genera of both the Scottopsyllus- and the Paramesochra-group. The aberrant genus Caligopsyllus Kunz, 1975, standing close to Apodopsyllus, is removed from the Paramesochra-group. P. brevifurca Galhano, 1970 is splitted into two subspecies and replaced in the genus Paramesochra. An attempt is made to assess the phyletic interrelationships of the Paramesochra-species and the resulting cladogram splits the genus into four species-groups. P. mielkei sp.n. is referred to the dubia-group and seems to be closely related to P. borealis Geddes, 1981. Finally, an amended diagnosis and a revised key to the species of the genus Paramesochra are presented.     

中药马蓝叶及其混乱品的比较鉴别

马蓝叶是加工传统中药青黛的主要原料。为了确保药材质量,作者对中药马蓝叶及其混乱品种球花马蓝、疏花马蓝、广西马蓝的原植物、药材性状、叶组织显微特征和薄层层析鉴别等进行了研究。指出其混乱品种虽与马蓝叶是同属植物,但不含马蓝叶的有效成分靛玉红,应仔细鉴别,不宜混用。     

双抗体免疫沉淀法纯化牛生长激素poly(A)~+RNA的研究

我们用双抗体免疫沉淀法,从牛垂体多聚核糖体中分离出牛生长激素特异多聚核糖体,由此多聚核糖体纯化的牛生长激素Poly(A)~+RNA,可以在麦胚体外翻译系统中和兔网织红细胞体外翻译系统中促进~(14)C-亮氨酸的参入。合成的含~(14)-亮氨酸的翻译产物中有91％可以被牛生长激素抗体沉淀。用SDS-11％PAGE对翻译产物进行鉴定表明,翻译产物在25KD处呈一条放射自显影带,与报导的牛生长激素前体分子量相吻合。     

酵母鉴定程序在酵母分类鉴定中的应用

本文介绍了Barnett等1985年编制并由剑桥大学发行的计算机软件《酵母鉴定程序》,以及如何使用该程序在IBM PC DOS操作系统上进行酵母菌的分类鉴定。我们使用该程序对从云南鸡足山和紫金山两地森林土壤中分离到的82株酵母菌进行了分类鉴定,其中:鉴定到种的有47株,占总株数的57.3％;鉴定到属但未能直接定到种的有21株,占总株数的25.6％;暂未定名的有14株,占总株数的17.1％。     

辽宁省番茄花叶病主要病毒和株系的研究

从辽宁南部及沈阳地区采集番茄花叶病样本111个(1985-1987),经鉴定得知主要毒原为番茄的烟草花叶病毒(TMV)占总调查的59.46％。黄爪花叶病毒(CMV)亦有发生仅占总调查的9.00％。还有一些系混合侵染(TMV和CMV)占21.62％。尚未认清毒原种的约占2.70％,接种无症的占7.20％。通过试验认为我省番茄上主要毒原为烟草花叶病毒,并进行了常规鉴定、提纯、电镜观察、光谱测定和血清测定等。对番茄上烟草花叶病毒16个分离物做了株系分化研究,按照Pelbam(1970,1972)〔14、15、16、17〕的抗性分类法应用番茄GCR一套品种接种观察,得知辽南及沈阳地区分布很广的番茄TMV分离物,均属TMV-O株系。故在番茄抗TMV育种中尚应考虑到抗1及2株系的能力。     

腐霉属分类性状评价及其中国的种

本文对腐霉属Pythium Pringsheim的研究历史作了简单的回顾,对该属的分类性状和系统进行了论述和评价,最后对中国已发现的55种腐霉,以检索表的方式进行了分类、检索。     

噬菌蛭弧菌噬菌斑的鉴别与纯化的研究

本文报告了使用１／５００营养肉汤双层琼脂培养基,在含有宿主菌及寄生菌混合物的软琼脂层中,蛭弧菌、变形虫及鞭毛虫等均可形成噬菌斑,但其大小、形态、扩展速度不同。鉴别方法除依据噬菌斑形态特征外,主要靠相差显微镜下的形态学观察。蛭弧菌的纯化用单斑传代,一个直径为１ｍｍ的噬菌斑含有约１０^５－６ｐｆｕ／ｍｌ（每毫升噬菌斑形成单位）。