Woolford J L, Steinman H M, Webster R E
Biochemistry. 1977 Jun 14;16(12):2694-700. doi: 10.1021/bi00631a017.
A complex containing the minor coat protein or adsorptionprotein (A protein) of bacteriophage fl has been solubilized from the fl virion, using the detergent deoxycholate. This complex was resolved from the fl DNA and from the fl major coat protein, or B protein, by gel filtration in the presence of deoxycholate. The A protein complex migrated as a single band on sodium dodecyl sulfate-urea-polyacrylamide gels corresponding to a molecular weight of 60 000. Analysis of the amino acid composition and amino terminal residues of this preparation indicates that the preparation contains a 20% contamination of additional protein species. Antibody against purified fd A protein is cross-reactive with deoxycholate-purified fl A protein and with fl phage. Electron microscopic observation of negatively stained complexes of fl phage with this anti-fd A protein antibody and ferritin conjugated goat anti-rabbit IgG antibody revealed phages with ferritin particles at their termini or complexes of two or more phages joined together at one end by ferritin, indicating that the complex of A protein molecules is located at one end of the filamentous fl virion.
利用去污剂脱氧胆酸盐已从噬菌体f1的病毒粒子中溶解出一种含有次要外壳蛋白或吸附蛋白（A蛋白）的复合物。在脱氧胆酸盐存在的情况下，通过凝胶过滤将该复合物与f1 DNA以及f1主要外壳蛋白或B蛋白分离。A蛋白复合物在十二烷基硫酸钠-尿素-聚丙烯酰胺凝胶上迁移为单一条带，其分子量对应于60000。对该制剂的氨基酸组成和氨基末端残基的分析表明，该制剂含有20%的其他蛋白质种类污染。针对纯化的fd A蛋白的抗体与脱氧胆酸盐纯化的f1 A蛋白以及f1噬菌体具有交叉反应性。用这种抗fd A蛋白抗体和铁蛋白偶联的山羊抗兔IgG抗体对f1噬菌体的负染复合物进行电子显微镜观察，发现噬菌体末端带有铁蛋白颗粒，或者两个或更多噬菌体通过铁蛋白在一端连接在一起的复合物，这表明A蛋白分子复合物位于丝状f1病毒粒子的一端。
