Schwartz Elisabeth F, Camargos Thalita S, Zamudio Fernando Z, Silva Luciano P, Bloch Carlos, Caixeta Fábio, Schwartz Carlos A, Possani Lourival D
Departamento de Ciências Fisiológicas, Instituto de Ciências Biológicas, Universidade de Brasília, Brasília DF 70910-900, Brazil.
Toxicon. 2008 Jun 15;51(8):1499-508. doi: 10.1016/j.toxicon.2008.03.029. Epub 2008 Apr 4.
This communication reports the separation of 80 fractions from the venom of the Ischnuridae scorpion Opisthacanthus cayaporum by high-performance liquid chromatography (HPLC). From these, 93 distinct components were identified by liquid chromatography/electrospray mass spectrometry (LC/ESI-MS) analysis, with molecular weights varying from 229.2 to 61,144.0 atomic mass units. Additionally, the HPLC fractions were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) which resulted in 221 distinct components, among which were 52 of the 93 obtained by LC/ESI-MS. The entire set of different molecular species found (total of 262 molecular masses) has a trimodal molecular weight distribution, with 42% of the components possessing 229.2-2985.3Da, 37% within the range of 3045.0-7258.6Da and 12% within the range 7458.4-9429Da. Seventeen peptides/proteins were isolated and were sequenced by Edman degradation, among which were a scorpine-like peptide (8315Da), presenting antimicrobial activity, and two phospholipase A2 with a molecular weight around 14kDa. The pharmacological effects of the venom were tested on isolated rat and insect (cockroach) nerves using the single sucrose-gap assay. The ED50 of the venom was 1.1mg/ml in insect nerves. Venom concentrations in the order of 3mg/ml causes only 9% reduction of compound action potentials (APs) of rat nerves, suggesting that this venom is rather specific for insects. Comparative analysis of venom from male and female O. cayaporum was performed by HPLC and MALDI-TOF-MS showing no qualitative variations, but rather quantitative differences among both samples.
本通讯报道了通过高效液相色谱（HPLC）从伊斯氏蝎Opisthacanthus cayaporum的毒液中分离出80个馏分。通过液相色谱/电喷雾质谱（LC/ESI-MS）分析，从这些馏分中鉴定出93种不同的成分，分子量在229.2至61,144.0原子质量单位之间。此外，通过基质辅助激光解吸/电离飞行时间质谱（MALDI-TOF-MS）对HPLC馏分进行分析，结果得到221种不同的成分，其中93种中有52种是通过LC/ESI-MS获得的。所发现的整套不同分子种类（总共262个分子质量）具有三峰分子量分布，42%的成分分子量在229.2 - 2985.3Da之间，37%在3045.0 - 7258.6Da范围内，12%在7458.4 - 9429Da范围内。分离出十七种肽/蛋白质并通过埃德曼降解法进行测序，其中有一个具有抗菌活性的类蝎毒素肽（8315Da）以及两个分子量约为14kDa的磷脂酶A2。使用单蔗糖间隙测定法在分离的大鼠和昆虫（蟑螂）神经上测试了毒液的药理作用。毒液在昆虫神经中的半数有效剂量（ED50）为1.1mg/ml。毒液浓度为3mg/ml时仅使大鼠神经复合动作电位（APs）降低9%，表明这种毒液对昆虫具有相当的特异性。通过HPLC和MALDI-TOF-MS对雄性和雌性Opisthacanthus cayaporum的毒液进行比较分析，结果显示两者在质量上没有差异，但在数量上存在差异。
