Francavilla M, Miranda P, Di Matteo A, Sarasini A, Gerna G, Milanesi G
Istituto di Genetica Biochimica ed Evoluzionistica CNR, Pavia, Italy.
J Gen Virol. 1987 Nov;68 ( Pt 11):2975-80. doi: 10.1099/0022-1317-68-11-2975.
A 646 bp fragment derived from a full length cDNA clone of genomic segment 9 of bovine rotavirus (NCDV strain) was inserted into Escherichia coli expression plasmid pEX1. The fragment encodes amino acids 50 to 265 of the major vital neutralization antigen VP7, a 326 amino acid long outer shell glycoprotein. Several transformed bacterial clones were isolated in which the recombinant plasmid directed the synthesis of a cro-beta-galactosidase-VP7 fusion protein that was recognized by rabbit polyclonal antibodies against NCDV rotavirus. Sera from rabbits immunized with the fusion protein specifically reacted with VP7 among NCDV virion polypeptides. The chimeric polypeptide was also specifically recognized by two monoclonal antibodies against UK strain rotavirus VP7 that exhibited virus-neutralizing activity. However, immune sera to the chimeric polypeptide showed no neutralizing activity against bovine rotavirus. These results are discussed in view of a recent report that a fusion VP7-beta-galactosidase polypeptide comprising 35 more amino acids at the carboxy terminus was able to induce neutralizing antibodies in mice to simian rotavirus SA11.
将源自牛轮状病毒（NCDV株）基因组第9节段全长cDNA克隆的一个646bp片段插入大肠杆菌表达质粒pEX1。该片段编码主要重要中和抗原VP7的第50至265位氨基酸，VP7是一种长度为326个氨基酸的外壳糖蛋白。分离出了几个转化细菌克隆，其中重组质粒指导合成了一种cro-β-半乳糖苷酶-VP7融合蛋白，该融合蛋白可被抗NCDV轮状病毒的兔多克隆抗体识别。用该融合蛋白免疫的兔血清能与NCDV病毒粒子多肽中的VP7发生特异性反应。该嵌合多肽还被两种抗英国株轮状病毒VP7且具有病毒中和活性的单克隆抗体特异性识别。然而，针对该嵌合多肽的免疫血清对牛轮状病毒无中和活性。鉴于最近有报道称，在羧基末端多含35个氨基酸的融合VP7-β-半乳糖苷酶多肽能够在小鼠中诱导产生针对猿猴轮状病毒SA11的中和抗体，对这些结果进行了讨论。
