Casal J I, Diaz-Aroca E, Ranz A I, Manclus J J
Inmunologia y Genetica Aplicada, S.A. (Ingenasa), Madrid, Spain.
Virology. 1990 Aug;177(2):764-7. doi: 10.1016/0042-6822(90)90545-3.
The linear single-stranded DNA genome of the porcine parvovirus, an autonomous parvovirus, was cloned in duplex form into the bacterial plasmid pUC18 using a simple and reliable method. These clones were stable during propagation in Escherichia coli JM109. The recombinant clones of porcine parvovirus were infectious when transfected into monolayers of swine testes cells as identified by the development of cytopathic effect, indirect immunofluorescence with specific antiserum, and hemagglutination assays. DNA isolated from progeny virus arising from transfected infectious clones was found to be indistinguishable from wild-type DNA by restriction enzyme analysis. Defective genomes could also be detected in the progeny DNA even though the infection was initiated with homogeneous, cloned DNA. The presence of the turn of the 5'-end loop seems to be necessary to get stable infectious clones.
猪细小病毒（一种自主细小病毒）的线性单链DNA基因组，采用一种简单可靠的方法以双链形式克隆到细菌质粒pUC18中。这些克隆在大肠杆菌JM109中繁殖时是稳定的。当将猪细小病毒的重组克隆转染到猪睾丸细胞单层中时具有感染性，这通过细胞病变效应的出现、用特异性抗血清进行间接免疫荧光以及血凝试验得以鉴定。通过限制性酶切分析发现，从转染的感染性克隆产生的子代病毒中分离出的DNA与野生型DNA无法区分。即使感染是从同源的克隆DNA开始的，在子代DNA中也能检测到缺陷基因组。5'-末端环的转折的存在似乎是获得稳定感染性克隆所必需的。
