First chemical synthesis of a scorpion alpha-toxin affecting sodium channels: the Aah I toxin of Androctonus australis hector.

Aah I is a 63-residue alpha-toxin isolated from the venom of the Buthidae scorpion Androctonus australis hector, which is considered to be the most dangerous species. We report here the first chemical synthesis of Aah I by the solid-phase method, using a Fmoc strategy. The synthetic toxin I (sAah I) was renatured in DMSO-Tris buffer, purified and subjected to thorough analysis and comparison with the natural toxin. The sAah I showed physico-chemical (CD spectrum, molecular mass, HPLC elution), biochemical (amino-acid composition, sequence), immunochemical and pharmacological properties similar to those of the natural toxin. The synthetic toxin was recognized by a conformation-dependent monoclonal anti-Aah I antibody, with an IC50 value close to that for the natural toxin. Following intracerebroventricular injection, the synthetic and the natural toxins were similarly lethal to mice. In voltage-clamp experiments, Na(v) 1.2 sodium channel inactivation was inhibited by the application of sAah I or of the natural toxin in a similar way. This work describes a simple protocol for the chemical synthesis of a scorpion alpha-toxin, making it possible to produce structural analogues in time.     

悬钩子属种质的评价

在进行了７省悬钩子资源调查的基础上,在南京建立了悬钩子属田间基因库。３年来对田间基因库内保存并开花结果的３０个种进行了开花结果性状的记栽和评价。内容包括果实特征,糖、酸、维生素类、氨基酸、矿质元素含量分析,染色体计数等。分析了种间和种内多样性物存在及在良种选育中利用的可能性。     

悬钩子种质评价标准

九十年代初在南京建立了悬钩子属田间基因库。考虑到国内外尚未发表悬钩子属种质评价标准,特拟定此标准供田间基因库使用。内容包括登记数据、引种数据、栽植数据、繁殖保存数据、植株数据、病虫害敏感性、同工酶酶谱、染色体计数和备注等９部分。在植株数据中有：１．植株类型;２．植株大小;３．生长势;４．刺;５．萌蘖;６．顶端生根习性;７．枝蔓寿命;８．叶（包括叶成分等共１０项）;９．花序;１０．花;１１．果（包括果实成分等共１８项）;１２．适应性;１３．丰产性     

桃花营养元素的分析与开发探讨

桃花含有较高的蛋白质和人体必需的各种氨基酸、维生素和微量元素。由于桃树在我国分布范围广泛,产花量大且需要人工疏花,使桃花的开发利用具有良好的条件。     

日立835─50型氨基酸分析仪故障排除六例

给出日立８３５－５０型氨基酸分析仪使用过程中出现的六种故障现象及判断排除方法     

皖南尖吻蝮蛇毒出血毒素Ⅳ的纯化与初步鉴定

从皖南尖吻蝮蛇（Ａｇｋｉｓｔｒｏｄｏｎａｃｕｔｕｓ）毒液中经ＤＥＡＥ－Ｓｅｐｈａｒｏｓｅ和ＳｅｐｈａｃｒｙｌＳ－２００两步凝胶柱层析首次纯化出一种中分子量出血毒素（简称ＡａＨⅣ）．经ＳＤＳ－ＰＡＧＥ和等电聚焦凝胶电泳测定其分子量为４４ｋＤ,等电点为ｐＨ５．０．从５００ｍｇ粗毒中可获得２０ｍｇＡａＨⅣ纯品．ＡａＨⅣ有较强的出血活性,最小出血剂量（ＭＨＤ）为０．４μｇ．     

Synthesis and antiplatelet, antiinflammatory, and antiallergic activities of 2-substituted 3-chloro-1,4-naphthoquinone derivatives

A series of 2-substituted 3-chloro-1,4-naphthoquinones was synthesized, and the antiplatelet, antiinflammatory, and antiallergic activities of these compounds were evaluated. The structure-activity relationships in this series were also examined. Most of the 2-alkyl/arylcarboxamido derivatives of 3-chloro-1,4-naphthoquinone showed potent activities with similar trends in each of the activities evaluated.     

神经生长因子结构与功能研究进展

神经生长因子(NGF)是神经营养因子家族的典型代表, 它控制着脊椎动物周围和中枢神经系统中部分神经元的发育和存活.NGF的三维结构是以“胱氨酸结”和β折叠为基础,它以二聚体的形式结合细胞表面的受体从而发生生物学效应.参与这些反应的氨基酸残基已通过化学修饰和定点突变法加以确定,这有助于更进一步理解其结构与功能的关系.