Cloning and Expression of Recombinant Human Thymosin in Yeast Pichia pastoris

The gene of human thyrnosin alpha 1 (hT(1)was synthesised according to favorite eodons of Pichia pastoris by PCR. N-terminal 28 amino acid residues of 40S ribosomal protein (RP), S24Ethat is N-aeetylserine were replaced by hT( 1 for the constitution of hT(1-RP fusion gene in order to express acetyllated thyrnosin α1. And also, the Asn-Gly bond was designed to faeiliate isolation of the target protein. The fusion gene was cloned into the expression vector, pPIC/gK. The constructs were transformed into HIS4 mutant strain GS115 by eleetroporation. Both SDS-PAGE analysis and Western blot analysis indicated that the fusion protein was expressed successfully.     

Expression，reflolding and preliminary characterization of recombinant snake venom metalloproteinases：Implication for the hemorrhagic mechanism

Two cDNAs encoding hemorrhagic snake venom metalloproteinase acutolysin A and non-hemorrhagic metalloproteinase(BR)were cloned into the expression vector pET-22b,respectively,and the corresponding two recombinant proteins,A-22b and BR-22b,were produced in inclusion bodies in E.coli BL21(DE3).The reombinant proteins were then subjected to solubilization,purification and refolding in vitro.A-22b showed hemorrhagic activity and fibronectin.Natural autolysin A had both hemorrhagic activity and proteolytic activity toward these substrates.BR-22b showed the proteolytic activities toward fibrinogen,but no hemorrhagic activity.In addition,two chimeric genes,C1 and C2,were constructed and cloned into pET-22b,and the corresponding recombinant proteins,C1-22b and C2-22b,were also expressed in inclusion bodies.C1-22b involved N-terminal 110 amino acidos of BR and C-terminal 95 amino acids of acutolysin A,while C2-22b contained N-terminal 108 amino acids of acutolysin A and C-terminal 112 amino acids of BR. The biological activities of A-22b and BR-22b,respectively.Our results suggested that N-terminal major subdomain of a snake venom metalloproteinase might play a key role in hemorrhagic activity and have an appreciable effect on the selectivity for protein substrates.     

B→O blood conversion

To maintain a constant supply of “universal blood type”,or group O red blood cells,has benefit in specialized transfusion condition.In this study, α-galactosidase cDNA was cloned from Catimor coffee bean grown in Hainan island,China,by the RT-PCR method.We have constructed a vector for α-galactosidase cDNA expression and transferred α-galactosidase cDNA into Pichia pastoris GS115 cells by electroporation.The recombinant α-galactosidase(r-α-GalE)was purified by cation ion exchange chromatography.After studying the biochemical characters of r-α-GalE we have succeeded in converting human erythrocytes from group B to group O.The animal experiment showed that transfusion of enzymetically converted group O red blood cells(ECORBC)was perfectly safe.     

基于相对下限的遗传算法

使用一种新的重组算子和适值函数尺度变换，提出了基于相对下限的遗传算法，并理论分析了该算法的收敛性。实验表明，该算法能较好地平衡种群多样性和选择压力的关系。     

基于矢量距的网络重组算法的设计与实现

网络重构技术在网络出现故障和安全问题时为网络的强壮性提供了有力保证·考虑到网络的复杂性、服务的可靠性、通信的动态变化的要求,参照了RIP协议后,在安全和服务质量方面增加了新的度量方法,提出了一个新的路由算法来实现移动网络的重组·     

校企上市:重组及运营模式

高科技企业成为公众公司上市,既是风险投资的战略性出口之一,又是企业发展的高级阶段.文章通过实例较详尽、系统地分析评价了我国A股市场上市的几种资产重组模式,并就相关问题提出一些创新建议,试图探讨高科技企业从孵化培育、重组上市到上市运营这一完整过程中的运作思路.特别是针对高科技企业发展的特点,对上市重组的模式进行了探讨,在调研和分析基础上提出了适合我国高校和科研院所改制重组的模式.     

高梁根质膜K~+转运蛋白在人工脂质体上的活性重组

将高粱根质膜中K~+ -ATPase活性重组入人工脂质体中 ,并研究了脂蛋白体的性质。结果表明 ,脂蛋白体中脂和蛋白质浓度与离子转运活性呈正相关 ,当其含粗提大豆磷脂且脂 /蛋白比率为 3 5时 ,其K+ 转运活性最大。     

重组人促性腺激素对小鼠排卵影响的机理

探讨不同剂量和组合的重组人促性腺激素对小鼠卵泡发育和排卵的影响及其与小鼠血清中雌、雄激素水平变化的相互关系.实验采用DNA重组技术合成的重组人促性腺激素对性成熟前雌性昆明白小鼠(22～24日龄)以不同剂量和组合进行超数排卵处理,结果表明,一定剂量和组合的重组促性腺激素的处理对小鼠卵泡的发育和血清中雌、雄激素水平产生较大影响,卵泡的正常发育及最终的排卵要求一定的重组人卵泡刺激素(r-hFSH)、重组人促黄体生成素(r-hLH)、重组人绒毛膜促性腺激素(r-hCG)的配比组合和相应的剂量范围.重组促性腺激素处理后小鼠卵泡的发育和排卵与雌、雄激素生成的量有关.     

离子交换层析分离纯化重组人血清白蛋白

通过层析实验，比较了几种阴离子交换剂在不同温度、pH值、离子强度、进样流速、进样浓度下对人血清白蛋白的吸队与脱附性能，研究了它们对人血清白蛋白和卵清蛋白的分离能力，并考察了桩层析过程中吸附载体对重组人血清白蛋白和杂蛋白的分离选择性，实验结果表明：版号为DEAE Sepharose FF的载体不仅对重组人血清白蛋白具有良好的分离度，而且有较高的回收率。