诺丽酵素中两个新的曲酸类化合物对胰岛素抵抗HepG2细胞葡萄糖摄取的影响（英文）

从诺丽酵素中分离获得两个新的曲酸类化合物nonikojic A (1)和nonikojic B (2),通过多种现代波谱技术确定了它们的化学结构.并对这2个化合物进行了胰岛素抵抗HepG2细胞葡萄糖摄取的活性评价,结果显示化合物1和2在50μmol/L剂量下均可显著地促进胰岛素抵抗HepG2细胞的葡萄糖摄取,从而改善胰岛素抵抗.     

Synthesis and characterization of insulin-5-Fu conjugate, enabling insulin as multi-drug cartier via dendritic approach

To enable insulin as multi-drug carrier, we designed and synthesized dendritic linker molecule bearing three 5-fluorouracil residues at the branch ends. The new conjugate showed excellent water solubility. The stabilities under different conditions were investigated. The results showed that the conjugate was a potential prodrug to release free 5-Fu.     

Site-specifically cleavage of oxidized insulin B chain with Zn（Ⅱ） ion studied by electrospray ionization mass spectrometry

The electrospray ionization mass spectrometry and tandem mass spectrometry investigation showed that the binding sites of Zn^2＋ with oxidized insulin B chain are His 5, His 10, and Arg 22, which lead to the selective cleavages of the peptide bonds at Ash 3- Gin 4, His 5-Leu 6, Gly 8-Ser 9, and Glu 21-Arg 22 of oxidized insulin B chain.     

还原型胰岛素A,B链相互作用的研究

用CD谱研究了厌氧条件下还原型胰岛素A,B链的相互作用。 结果表明,S-磺酸型胰岛素A,B链间及在过量DTT存在下的还原型胰岛素A,B链间基本无相互作用,分离链及混合链均表现为接近无序结构。而按巯基与磺酸基比为1.2和0.6加入DTT时,胰岛素入B链间存在相互作用,并导致α螺旋含量增加。在按巯基与磺酸基比为0.6加入DTT时,近紫外CD谱表明存在着二硫键的极快形成过程,而按巯基与磺酸基比为1.2加入DTT时,巯基基本不氧化,表明有序二级结构的增加与巯基氧化无直接关系,而仅为二条肽链间相互作用的表现。对按不同巯基与磺酸基比加入DTT时,DTT与S-磺酸型胰岛素链上的巯基交换存在二种方式,以及小环关闭的胰岛素A链对胰岛素链间的相互作用并无促进作用的可能性进行了讨论。     

2.1分辨率A1-(L-色氨酸)胰岛素晶体结构研究

本文对A1修饰色氨酸胰岛素进行了晶体学的深入研究。晶体的空间群为R3,晶胞参数:a_H=80.3,c_H=37.5。应用立体化学制约最小二乘法并结合差值Fourier图人工分析对2.1的结构模型进行了多次调整和精化,最终偏离因子R=O.195。独立区两个A1-(L-色氨酸)胰岛素分子A链N端的A1色氨酸残基在电子密度图上表现十分清晰,其中分子ⅠA1色氨酸残基侧链具有两种构象。本文从结构角度推断三方四锌胰岛素分子Ⅱ的结构是一种低活性构象存在于六聚体内。此外,对有关胰岛素结构与功能的一些问题进行了讨论。     

5-对羟基苄基-2,4-噻唑烷二酮的合成

以对甲氧基苯胺为原料,经3步反应合成了胰岛素增敏剂噻唑烷二酮类药物的关键中间体5-(4-羟基苄基)-2,4-噻唑烷二酮,总收率20.4%,其结构经1HNMR确证。     

Silica-supported Macroporous Chitosan Bead for Affinity Purification of Trypsin Inhibitor

Macroporous cross-linking chitosan layer coated on silica gel （CTS-SiO2） was prepared by phase inversion and polyethylene glycol （PEG）molecular imprinting methods. Formation of macroporous surtace was investigated by scanning electron microscopy （SEM） and BET analysis.The prepared bead was activated by reacting with 1,2-ethylene digiycidyl ether for introducing epoxy groups, and trypsin could be efficiently immobilized on the bead as a biospecific ligand.The bead bearing trypsin was employed to purify trypsin inhibitor （TIs） from egg white as affinity adsorbent.     

Studies on the Renaturation with Simultaneous Purification of Recombinant Human Proinsulin with Unit of Simultaneous Renaturation and Purification of Protein in Semi－preparative Scale

The recombinant human proinsulin (rh-proinsulin) is the precursor of insulin, which is connected with C- peptide between the carboxyl-terminal of chain A and NH2-terminal of chain B of insulin. In the presences of trypsin and carboxypeptides B (CPB), the C-peptide can be cleaved from the special two peptides of rh-proinsulin and the recombinant human insulin (rh-insulin) can be, thus, obtained1,2. The rh-proinsulin expressed in E. coli exists as inclusion body, hardly dissolves in water,…     

去B链羧端六肽(B25—30)胰岛素初步结晶学研究

去B链羧端六肽(B25—30)胰岛索,采用悬挂液滴气相扩散法,在柠檬酸纳缓冲液pH 5.8;含有丙酮和氯化钠体系中,获得可供X射线晶体结构分析用的单晶体,其衍射分辨率在1.5以上,晶体外形为三角形。属于单斜晶系,空间群为C2,晶胞参数为α=42.60,b=37.87,c=27.118,β=125.35°。其结构分析工作正在进行中。