缺氧性肺动脉高压大鼠的降钙素基因相关肽含量和分布

目的：研究降钙素基因相关肽（ Ｃ Ｇ Ｒ Ｐ） 对缺氧性肺动脉高压（ Ｈ Ｐ Ｈ） 的影响。方法：应用常压缺氧方法建立大鼠肺动脉高压动物模型;采用酶联免疫测定法测定大鼠血浆降钙素基因相关肽的含量;用免疫组织化学染色法观察肺组织中 Ｃ Ｇ Ｒ Ｐ 的分布。结果：缺氧组大鼠血浆 Ｃ Ｇ Ｒ Ｐ 含量较正常对照组有明显下降（ Ｐ＜ ００１） ,且血浆 Ｃ Ｇ Ｒ Ｐ 水平与肺动脉平均压（ ｍ Ｐ Ａ Ｐ） 呈负相关（ Ｐ＜００５） ;正常大鼠肺组织有极少量 Ｃ Ｇ Ｒ Ｐ 样免疫物质,缺氧组大鼠肺组织有大量 Ｃ Ｇ Ｒ Ｐ 样免疫物质。结论：缺氧时血浆 Ｃ Ｇ Ｒ Ｐ 含量减少可能是其释放减少所致, Ｃ Ｇ Ｒ Ｐ 在缺氧继发肺动脉高血压中起重要的肺循环调节作用。     

Synthesis, structure-activity relationship of nociceptin and its fragments

Nociceptin (NC) and its 4 fragments have been synthesized by solid phase peptide synthesis. Their hypertensive activity and mechanism, MVD assay and structure-activity relationship have been investigated. Results show that NC(1-13)NH2 is the smallest fragment that shares the same activity with NC. The truncation of C-terminal not only leads the decrease of receptor affinity but also the changes of receptor selectivity. The entire sequence may not be required for the full activity since NC(1-13)NH2 is as active as NC. Arg-Lys at the 12-13 position of C-terminal plays an important role in the activity of NC. The hypotensive activity of NC does not antagonize the hypertensive activity of renin-angiotensin system.     

Photo-induced reactions of sulfonated aluminum phthalocyanine with peptide

The photosensitized oxidation mechanism of peptide in the presence of the ClAIPcS is studied by UV-Vis spectroscopic method. It is found that the oxidation of peptide is totally quenched in 1.1 × 10-2 mol/L NaN3 solution, and the same reaction cannot proceed in the dark. K3Fe(CN)6 and L-Cys cannot quench the reaction. Therefore, the reaction mechanism is mainly Foote's type Ⅱ. This reaction process can be inferred as follows: ( i ) active oxygen can attack acylamide bond near by carbon atom; ( ii ) carboxyl group departs from peptide; (iii ) l-benzazole cycle is destroyed when reaction is continued; (iv) the peptide is completely damaged.     

Rational screenning in combinatorial peptide libraries of protein functional loop

Redesigning the sequences of protein loops is a frequent practice in protein design. Based on the new results of protein loop database analysis, a rational computer simulation strategy is proposed to obtain functional proteins, which exploits a fast and accurate program to calculate the protein loop conformation, and at the same time, combines molecular docking method with combinatorial chemistry strategy to screen the combinatorial peptide library of protein loops. A characteristic of this method is that it separates the conformation computation of backbone from that of side chain and incorporates side chain growth into the docking procedure and therefore greatly reduces the computation by converting the huge computation on explosive conformations to relatively small computation on limited canonical backbone structures and side chain growth. This method can be practically used in screening combinatorial peptide libraries of protein loops.     

Natural peptide analgesics: the role of solution conformation

Endogenous opioids have been studied extensively since their discovery, in the hope of finding a perfect analgesic, devoid of the secondary effects of alkaloid opioids. However, the design of selective opioid agonists has proved very difficult. First, structural studies of peptides in general are hampered by their intrinsic flexibility. Second, the relationship between constitution and the so-called 'bioactive conformation' is far from obvious. Ideally, a direct structural study of the complex between a peptide and its receptor should answer both questions, but such a study is not possible, because opioid receptors are large membrane proteins, difficult to study by standard structural techniques. Thus, conformational studies of opioid peptides are still important for drug design and also for indirect receptor mapping. This review deals with conformational studies of natural opioid peptides in several solvents that mimic in part the different environments in which the peptides exert their action. None of the structural investigations yields a convincing bioactive conformation, but the global conformation of longer peptides in biomimetic environments can shed light on the interaction with receptors. Received 15 April 2001; received after revision 10 May 2001; accepted 11 May 2001     

新型肾综合征出血热EIA诊断试剂盒的研制

用多肽合仪合成汉坦病毒核衣壳蛋白（NP）(aa17－66）50个氨基酸残基的核心序列,以此为抗原,建立特羿性检测抗汉坦病毒IgG和IgM的酶联免疫吸附剂测定法（ELISA）,通过实验发现这一序列具有较强的抗原性,研制出了以合成肽为抗原的新型牧场异性检测抗汉坦病毒IgG和IgM的诊断试剂盒,通过对肾综合征出血热抗体阳性血清的检测,效果良好。     

心肌型脂肪酸结合蛋白特异性亲和配体的筛选

心肌型脂肪酸结合蛋白(H-FABP)是一种低相对分子质量的蛋白质,其相对分子质量为14 000~15 000,在心肌中含量丰富.H-FABP在脂肪酸的运输、脂类的代谢、调节细胞增殖与分化等方面具有重要的作用,是检测急性心肌梗塞(AMI)的有效生物学标志物.以H-FABP为靶标,采用噬菌体表面展示随机十二肽库对H-FABP的特异性亲和配体进行了筛选,经四轮筛选得到一个ELISA检测阳性特征序列:W-P-H-Q-K-L-H-L-M-R-H-S,为临床检测急性心肌梗塞提供了一种新的方法.     

美洲拟鲽(Pseudopleuronectes americanus)抗冻肽基因在大肠杆菌中的表达

将美洲拟鲽抗冻肽基因克隆于原核高效表达载体ｐＫＫ２２３－３中,经酶切分析、ＰＣＲ检测筛选出重组克隆ｐＭＫ１１,转化大肠杆菌ＪＭ１０９和ＤＨ５α,ＩＰＴＧ诱导２～３ｈ后,超声波裂解细菌产物,在ＳＤＳ－ＰＡＧＥ电泳图谱分子量９ｋＤａ处显示出一条明显的蛋白带,与美洲拟鲽抗冻肽大小一致,表明美洲拟鲽抗冻肽基因在大肠杆菌中表达,为进一步研究抗冻肽基因在大肠杆菌中的表达水平及条件打下基础．     

Peptide primary messengers in plants

The peptide primary messengers regulate embryonic development, cell growth and many other activities in animal cells. But recent evidence verified that peptide primary messengers are also involved in plant defense responses, the recognition between pollen and stigma and keep the balance between cell proliferation and differentiations in shoot apical meristems. Those results suggest that plants may actually make wide use of peptide primary messengers, both in embryonic development and late life when they rally their cells to defend against pathogens and insect pests. The recent advance in those aspects is reviewed.     

抗冻肽基因在植物表达载体中的构建

植物表达载体P^Bin438经HindⅡ和EcoPⅠ双酶切,回收其HindⅡ－BmaHⅠ-Sal-EcoRⅠ片段和P^UC19HⅢ-EcoRI片段连接,构建成载体记为P^UC38。将含AFP基因的克隆经BamHI,XhoⅠ双酶切,得到的BamHI-AFP-XhoⅠ片段装入P^UC38BanHI-SalⅠ位点,克隆AFP基因。然后再用HindⅢ、EoR1双酶切AFP基因,插入P^Uin438的HindⅢ-EcoRⅠ位点,进而构建成带有AFP基因的植物表达载体,为进一步研究AFP基因在植物中表达奠定了基础。