Hosoda J, Cone R
Proc Natl Acad Sci U S A. 1970 Aug;66(4):1275-81. doi: 10.1073/pnas.66.4.1275.
Radioisotopically labeled T4-proteins extracted from purified capsids and phage and from infected cells were separated by gel electrophoresis in the presence of sodium dodecyl sulfate and a reducing reagent. They were identified by autoradiography and by counting of the fractionated gels. Four major protein bands (F, A, D, and E) were detected in capsid and phage. These accounted for more than 90% of the total capsid protein and 70% of the phage protein (60% of the total capsid protein was in A-band). Coelectrophoresis of [(14)C]proteins from capsids and [(3)H]proteins from phage-infected cells indicated that the protein coded by gene 23 (P23) was a peptide chain approximately 25% longer than A-protein. Pulse-chase experiments combined with differential extraction indicated that conversion of P23 into A-protein and alteration of the protein coded by gene 22 (P22) appeared to be vital steps in formation of normal capsids. Mutations in several other genes known to prevent normal capsid formation inhibited conversion of P23 to A-protein and alteration of P22.
从纯化的衣壳、噬菌体以及受感染细胞中提取的放射性同位素标记的T4蛋白，在十二烷基硫酸钠和还原剂存在的情况下通过凝胶电泳进行分离。通过放射自显影和对分级凝胶进行计数来鉴定它们。在衣壳和噬菌体中检测到四条主要蛋白带（F、A、D和E）。这些蛋白带占衣壳总蛋白的90%以上，占噬菌体蛋白的70%（衣壳总蛋白的60%在A带）。来自衣壳的[(14)C]蛋白与来自噬菌体感染细胞的[(3)H]蛋白进行共电泳表明，基因23编码的蛋白（P23）是一条比A蛋白长约25%的肽链。脉冲追踪实验结合差异提取表明，P23转化为A蛋白以及基因22编码的蛋白（P22）的改变似乎是正常衣壳形成的关键步骤。已知几个其他阻止正常衣壳形成的基因突变会抑制P23向A蛋白的转化以及P22的改变。
