丝组二肽对DNA的切割作用的研究

近20年来,人工核酸切割试剂的研究一直是生物化学中最为活跃的前沿领域之一,研究人工核酸切割试剂的主要目的是合成定点切割试剂,后者是一种重要的分子生物学工具,在疾病的基团治疗、反义PCR技术等领域中有着重要的应用价值。此外,人工核酸切割试剂还可以在足迹技术和核酸高级结构的研究中用作高分辨率的化学探针。     

磷酰化组氨酸形成六配位磷中间体的理论研究

用MNDO方法对磷酰化组氨酸磷上酯交换反应侧链咪唑基所参与的六配位磷机理进行了研究。六配位磷中间体形成后,使咪唑基对面的异丙氧基反应活性提高。当磷上酯交换反应发生时,异丙氧基离去和另一分子醇进攻磷,从咪唑基的对面发生,在能量上和空间上都是有利的。六配位磷机理比较好地解释了咪唑的催化作用。     

Synthesis and Theoretical Studies of Phosphoryl Amino Acid Analogue

Phosphoryl amino acids and their analogues are continuing to be increasingly important as potential enzyme inhibitors, mechanistic probes for proteases^[1,2]. Previously, a series of investigations on the structure-reactivity relationship about phosphoryl amino acids 1 had been carried out, the results showed that the co-participation of phosphoryl group, carboxyl group and residues of amino acids were essential and their biomimic reaction mechanisms were commonly through a penta-coordinate intramolecular mixed carboxylic-phosphoric anhydride intermediates^[3].     

Triality and Dual Equivalence Between Dirac Field and Topologically Massive Gauge Field

It is proved that there exists a vector representation of Dirac＇s spinor field and. in one sense it is equivalent to biquaternion （i.e. complexified quaternion） representation. This can be considered as a generalization of Cartan＇s idea of triality to Dirac＇s spinors. In the vector representation the first-order Dirac Lagrangian is dual-equivalent to the two-order Lagrangian of topologically massive gauge field. The potential field which corresponds to the Dirac field is obta/ned by using master （or parent） action approach. The novel gauge field is self-dual and contains both anti-symmetric Lee and symmetric Jordan structure.     

磷酰化氨基酸反应性质的理论研究

采用量子化学计算研究了磷酰化氨基酸的反应性质,包括N-磷酰氨基酸成肽反应、成酯反应、磷上酯交换反应和磷上的N→O迁移反应的机理以及计算模型和计算方法的选择,并从理论上解释了自然界选择α-氨基酸而不是β,γ-氨基酸的实验事实.     

太阳活动极小时期地磁共转扰动的似稳结构——第13至20太阳周

本文运用数字滤波技术和谐和分析方法,统计研究了第13至20太阳周极小时期地磁C₉指数的共转变化。得到的主要结果是:这种共转变化具有相当稳定的Carrington周分布结构,太阳活动奇数周与偶数周变化的位相接近相反;偶数周分布的左右两峰各具有相同的极性,分别来源于北、南两太阳半球;而两峰的位置均随时间逆太阳自转方向而发生漂移。这说明稳定太阳风高速流起源于太阳深部,并随太阳22年磁周交替地具有相当稳定的分布位形。     

Triality and Dual Equivalence Between Dirac Field and Topologically Massive Gauge Field

It is proved that there exists a vector representation of Dirac‘s spinor field andin one sense it is equivalent to biquaternion (i.e. complexified quaternion) representation. This can be considered as a generalization of Cartan‘s idea of triality to Dirac‘s spinors. In the vector representation the first-order Dirac Lagrangian is dual-equivalent to the two-order Lagrangian of topologically massive gauge field. The potential field which corresponds to the Dirac field is obtained by using master (or parent) action approach. The novel gauge field is self-dual and contains both anti-symmetric Lee and symmetric Jordan structure.     

A New Intermolecular Phosphoryl Transfer between Serine and Histidine Residues

Phosphoryl transfer constitutes one of the most important reactions in functionalized molecules, bioorganic chemistry and biochemistry.[1] The transformations are involved in diverse processes, such as activated state change of phosphorus, DNA/RNA synthesis, energy metabolism and signal transduction. So, phosphoryl transfer reaction which can be performed by either intramolecular or intermolecular phosphorylation and dephosphorylation mechanism has been investigated by many scientists in wide fields.     

表面解吸常压化学电离源的研制及应用

根据表面解吸常压化学电离源(SDAPCI)对表面痕量待测物进行常压解吸化学电离的原理,自行研制了SDAPCI电离源及其与线性离子阱(LTQ)质谱仪的接口,成功地在LTQ上实现了表面解吸常压化学电离。此方法无需样品预处理,直接利用电晕放电产生的H3O 在常压下对待测样品进行表面解吸化学电离,避免了甲醇等有毒试剂的使用。在优化的仪器参数条件下,分别用正/负离子模式成功地检测了片剂药品中的氯雷他定、乙酰氨基酚等活性成分和其它不同表面上TNT、氨基酸和多肽等物质,对这些常见物质的检出限不高于10pg/cm2。采用氩气作为电离试剂,观测到乙酰氨基酚、多肽等物质形成的自由基阳离子,提出了在氩气氛围中获得自由基阳离子的可能机理。实验表明SDAPCI具有灵敏度较高,选择性好,适用范围宽等特点,适合用于药品、食品等非破坏、无污染检测以及对复杂基体物质进行快速现场分析。     

In situ N-phosphorylation of oligopeptides for fast atom bombardment mass spectrometry

Positive ion fast atom bombardment mass spectrometry (FABMS) of in situ N-phosphorylated oligopeptides showed intense quasi-molecular ions together with the successive alkene loss fragment ions, which afford multiple checks of the unequivocal reality of the relative molecular mass of the tested samples. More interesting, in a novel cleavage pattern only the N-phosphoryl fragment ions gave intense peaks, the C-terminal series ions being suppressed. For each of the N-terminal ions, losses of alkenes also occur to provide multiple checks for the existence of these ions. The FABMS of the in situ N- phosphorylated oligopeptides might provide an easily accessible routine method for peptide sequencing.