Wang Jeng-Hwan, Liang Chi-Ming, Peng Jei-Ming, Shieh Jeng-Jer, Jong Ming-Hwa, Lin Yeou-Liang, Sieber Martin, Liang Shu-Mei
Institute of Bioagricultural Sciences, Academia Sinica, No. 128 Academia Road, Section 2 Nankang, Taipei 11529, Taiwan.
Vaccine. 2003 Sep 8;21(25-26):3721-9. doi: 10.1016/s0264-410x(03)00363-3.
VP1, a capsid protein of foot-and-mouth disease virus (FMDV), contains neutralizing epitopes of the virus. Due to its poor water solubility, recombinant Escherichia coli derived VP1 (rVP1) has previously been used mainly in a denatured form and is not well characterized. Here, using SDS to assist protein refolding and then removing SDS with a detergent removing column, we have successfully purified rVP1 in two aqueous-soluble forms, i.e. monomer and dimer. Studies showed that dimerization occurs by an inter-molecular disulfide bond between two cysteine residues at position 187 of each monomer. Heat treatment revealed that rVP1 dimer exhibited a more thermal-stable conformation than the monomeric form. Both monomeric and dimeric rVP1 reacted with anti-FMDV antibodies. Immunization studies demonstrated that vaccination of swine with either forms of rVP1 was effective in generating immune responses and protecting them from viral challenge.
口蹄疫病毒（FMDV）的衣壳蛋白VP1包含该病毒的中和表位。由于其水溶性较差，此前源自重组大肠杆菌的VP1（rVP1）主要以变性形式使用，且特性尚不明确。在此，我们利用十二烷基硫酸钠（SDS）辅助蛋白质复性，然后用去污剂去除柱去除SDS，成功纯化出两种水溶性形式的rVP1，即单体和二聚体。研究表明，二聚化是由每个单体187位的两个半胱氨酸残基之间的分子间二硫键形成的。热处理显示，rVP1二聚体比单体形式表现出更热稳定的构象。单体和二聚体形式的rVP1均能与抗FMDV抗体发生反应。免疫研究表明，用任何一种形式的rVP1对猪进行疫苗接种都能有效产生免疫反应，并保护它们免受病毒攻击。
