东亚钳蝎短链K+通道毒素BmP05基因多态性分析

基于从东亚钳蝎中鉴定的低电导Ca^2＋激活K^＋通道毒素BmP05的蛋白质和前体核苷酸序列，采用5’和3’RACE（rapid amplification of cDNA ends）技术，成功地从东亚钳蝎毒腺组织中分离到了一系列与BmP05前体核皆酸序列高同源性的cDNA序列，它们含有完整开放阅读框（open reading frame，ORF），彼此同源性很高，有的突变导致编码不同氨基酸，有的只足沉默突变，基因组克降结果进一步显示，尽管来源不同个体蝎的BmP05基因组的结构相同，但它们的基因组序列片不完全一致，在第二个外显子和内含子区域发生许多突变。BmP05在cDNA水平的多态性与其在基因组水平的多态性一致。所有结果表明，东亚钳蝎的毒素基因存在个体多态性。     

Derivatization of azaspiracid biotoxins for analysis by liquid chromatography with fluorescence detection

Azaspiracids (AZAs) are an important group of regulated lipophilic biotoxins that cause shellfish poisoning. Currently, the only widely available analytical method for quantitation of AZAs is liquid chromatography-mass spectrometry (LC-MS). Alternative methods for AZA analysis are needed for detailed characterization work required in the preparation of certified reference materials (CRMs) and by laboratories not equipped with LC-MS. Chemical derivatization of the amine and carboxyl groups on AZAs was investigated for the purpose of facilitating analysis by LC with fluorescence detection (FLD). Experiments towards chemical modification of AZA1 at the amine achieved only limited success. Derivatization of the carboxyl group, on the other hand, proved successful using the 9-anthryldiazomethane (ADAM) method previously applied to the okadaic acid (OA) group toxins. Extraction and clean-up methods were investigated for shellfish tissue samples and a post-reaction solid phase extraction procedure was developed for the AZA ADAM derivatives. Chromatographic separations were developed for the LC-FLD analysis of derivatized AZAs alone or in the presence of other derivatized toxins. This new analytical method for analysis of AZAs enabled verification of AZA1-3 concentrations in recently certified reference materials. The method demonstrated good linearity, repeatability and accuracy showing its potential as an alternative to LC-MS for measurement of AZAs.     

固相萃取-超高效液相色谱-串联质谱法检测婴幼儿奶粉中的7种链格孢霉毒素

婴幼儿奶粉配料中的植物油易受到链格孢霉菌污染,因而链格孢霉毒素(ATs)成为该类食品的重点检测对象.该研究建立了超高效液相色谱-串联质谱法快速检测婴幼儿奶粉中链格孢酚、链孢酚单甲醚、交链孢霉烯、细交链孢菌酮酸、腾毒素、交链孢毒素Ⅰ、细格菌素7种ATs的方法.通过参数优化确定最佳的质谱与色谱条件,选取BEH-C18色谱柱...     

固相萃取/超高效液相色谱-串联质谱法测定贝类中3种短裸甲藻毒素

建立了同时测定贝类中3种短裸甲藻毒素的超高效液相色谱-串联质谱法。样品采用丙酮提取、C18固相萃取柱净化;以5 mmol/L乙酸铵(含0. 1%甲酸)-乙腈为流动相,ACQUITYTMUPLC BEH C18色谱柱进行分离,在多反应监测模式下进行测定,外标法定量。结果表明,3种目标物在1. 0～100μg/L质量浓度范围内线性良好,相关系数(r~2)不小于0. 996,方法定量下限为3. 0μg/kg,回收率为80. 0%～87. 5%,相对标准偏差为1. 3%～5. 4%。该方法前处理简单,灵敏度高,稳定性好,适用于贝类中3种短裸甲藻毒素的同时测定。     

海洋毒素电化学生物传感器

由藻类产生的海洋毒素对人类健康和环境安全构成了较大威胁,对其进行快速准确的检测是减小海洋毒素危害的有效手段之一。电化学生物传感器具有快速简便、灵敏度高、检测限低和成本低等特点,为检测海洋毒素提供了新的技术途径。目前,应用于海洋毒素检测中的电化学生物传感器主要有免疫传感器、酶传感器和DNA传感器等。本文综述了迄今为止国内外海洋毒素电化学生物传感器研究所取得的成果,并对其当前研究存在的问题和未来发展趋势进行探讨和展望。     

利用电压敏感荧光染料测定贝体中的麻痹性贝毒

麻痹性贝毒(paralytic shellfish poisoning, PSP)是分布最广、危害最大的赤潮毒素,可阻断钠离子通道从而抑制动作电位的形成导致动物体中毒。以膀胱癌移行细胞T24为实验材料,采用电压敏感荧光染料bis-oxonol,根据PSP毒素GTX2,3对藜芦定诱导细胞去极化的抑制作用,建立了一种麻痹性贝毒电压敏感荧光染料检测法。实验结果显示,在2～100 ng·mL-1范围内,PSP毒素GTX2,3可显著改变培养体系的荧光强度,GTX浓度与荧光强度之间存在很好的线性关系。市售贝类PSP毒素检测结果表明,此方法测定结果与小鼠法基本一致,但灵敏度更高,说明根据GTX浓度与荧光强度之间的线性关系可实现对样品中PSP毒素的快速检测。利用电压敏感荧光染料测定贝体中的麻痹性贝毒是一种非常有潜力的贝毒快速筛查方法。     

Crystal Structure of a Rearranged Cage Compound, 3-Hydroxy-4-aza-8-oxoheptacyclo [9.4.1.0<Superscript>2,10</Superscript>.0<Superscript>3,14</Superscript>.0<Superscript>4,9</Superscript>.0<Superscript>9,13</Superscript>.0<Superscript>12,15</Superscript>]tetradecane

Abstract  Polycyclic hydrocarbon compounds exhibit a wide variety of biological activities, ranging from antiviral to Parkinson’s disease. Several structures such as the adamantanes have reached clinical status and are used therapeutically to treat, amongst others, neurodegenerative disorders such as Alzheimer’s. Polycyclics have also been utilised as carrier molecules to facilitate entry of drugs into the brain. The synthesis, molecular and crystal structure of a new polycyclic compound, 3-hydroxy-4-aza-8-oxoheptacyclo[9.4.1.0^2,10.0^3,14.0^4,9.0^9,13.0^12,15]tetradecane, are reported. NMR spectroscopy was applied for structure elucidation of the novel compound and a rearrangement mechanism is proposed for its formation. This compound crystallises in the orthorhombic system, space group Pbca (no. 61). The unit cell parameters are: a = 12.3763 (7), b = 11.6597 (6), c = 15.0539 (8) ?, V = 2172.3 (2) ?³ , and Z = 8 molecules in the unit cell. The reported structure was confirmed by X-ray analysis, which showed that the title molecules associate into centrosymmetric dimers via N–H···O hydrogen bonding. Index Abstract  The synthesis and structure of a new polycyclic compound, 3-hydroxy-4-aza-8-oxoheptacyclo[9.4.1.0^2,10.0^3,14.0^4,9.0^9,13.0^12,15]tetradecane, are reported in this article.      

Structural Characterization of Venom Toxins by Physical Methods and the Perspectives on Structure-Function Correlation of Proteins

This account describes work in our laboratories on the application of physical methods to the structural studies of various toxins during the past few years. A general review of background and the meaningful results obtained from these approaches are described. The results are compared with updated information on related subjects carried out at other laboratories. Examples of structural studies on some small toxins present abundantly in Formosan cobra (Naja naja atra), one of the indigenous toxic snakes in Taiwan, are given with the emphasis on the identification and characterization of complex toxic protein components based on near-infrared Fourier transform Raman Spectroscopy. We will also describe our initial efforts in solving the solution structures of several small proteins and peptides by means of two-dimensional nuclear magnetic resonance (2D-NMR) and computer-simulated modeling. The structural information obtained by these modem physical techniques provides the framework for unraveling the complex structure-activity relationships engendered by these biomolecules.     

Application of a novel lipophilized fluorescent dye in an optical nitrate sensor

A new lipophilic pH probe (1-hydroxypyrene-3,6,8-tris-octadecylsulfonamide) has been synthesized, and its spectral properties and applications in a solid state nitrate sensor are shown. The sensor is investigated with respect to sensitivity, limits of detection, and selectivity over other anions found in drinking water.Abbreviations used HPTS trisodium-1-hydroxy-pyrene-3,6,8-trisul-fonate - HPTS-TO 1-hydroxypyrene-tris-3,6,8-octadecylsulfonamide - TDMACl tridodecylmethylammonium chloride - PVC poly(vinyl chloride) - DOS bis-(2-ethylhexyl)-sebacate - THF tetrahydrofurane - DMF dimethylformamide