Dickinson M J, Townsend R
Department of Virus Research, John Innes Institute, Colney Lane, Norwich NR4 7UH, England.
Virology. 1985 Oct 15;146(1):102-10. doi: 10.1016/0042-6822(85)90056-x.
A short-tailed polyhedral spiroplasmavirus, ai, with a plaque morphology typical of temperate phages and a linear double-stranded DNA genome which can circularise due to the presence of cohesive ends, was able to lysogenise Spiroplasma citri. Lysogenic sporoplasmas spontaneously released ai virus at a low level, and were immune to superinfection by the released virus, but not to infection by two serologically related viruses. These properties were retained following repeated cultivation in virus antiserum. Viral sequences were detectable in host DNA by probing with recombinant DNA clones of ai fragments in coliphage M13 vectors. All strains of S. citri examined contained a deleted form of ai integrated as a cryptic prophage. We propose that ai circularises and integrates into the host genome adjacent to the cryptic prophage by a site-specific recombination event. Evidence of a correlation between lysogenisation and the attenuation of pathogenicity is presented.
一种短尾多面体螺旋体病毒ai，具有典型的温和噬菌体噬菌斑形态和线性双链DNA基因组，由于存在粘性末端可环化，它能够使柑橘螺原体溶源化。溶源化的螺原体以低水平自发释放ai病毒，并且对释放出的病毒的超感染具有免疫力，但对两种血清学相关病毒的感染没有免疫力。在病毒抗血清中反复培养后，这些特性得以保留。通过用噬菌体M13载体中的ai片段重组DNA克隆进行探测，可在宿主DNA中检测到病毒序列。所检测的所有柑橘螺原体菌株都含有作为隐蔽原噬菌体整合的缺失形式的ai。我们提出，ai通过位点特异性重组事件环化并整合到宿主基因组中隐蔽原噬菌体附近。文中给出了溶源化与致病性减弱之间相关性的证据。
