Covalently closed circular duplex DNA of Epstein-Barr virus in a human lymphoid cell line.

摘要: Abstract A non-integrated form of Epstein-Barr virus DNA was purified from the Burkitt lymphoma-derived human lymphoid cell line Raji by CsCl density gradient centrifugation and neutral glycerol centrifugation. This intracellular sediments at a rate typical covalently closed circular molecule size genome in both alkaline solution. Treatment with low doses X-rays leads to discontinuous conversion molecules sedimentation properties open (a duplex containing one or more single-strand breaks). The direct observation large electron microscopy further confirms structure part viral DNA. Such were not detected corresponding fractions virus-negative lines. In ethidium bromide/CsCl experiments, behaves as twisted, circles same initial superhelix polyoma latter additional purification technique permits isolation > 90% pure non-producer cells. molecular weight cells, determined contour length measurements, is within experimental error that linear particles.