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Temperature dependent structural changes of intraphage T7 DNA.

A Fekete·G Rontó·L A Feigin·V V Tikhonychev·K Módos
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Abstract

The phenomena connected with the first phase transition step of the native T7 phage at 40 degrees-65 degrees C have been studied using various methods. In this temperature range a) the optical melting curve shows an absorption decrease, b) the maximum of the small-angle X-ray scattering characteristic for DNA packing disappears, c) there is a drop of biological activity and d) there are changes in the structure of the difference absorption spectra of native phages versus isolated DNA. All data are interpreted assuming a structural change of the DNA due to the release of its protein coat towards the end of the first phase transition step (at 60 degrees-65 degrees C in the case of M9 buffer). Above this temperature the intraphage DNA packing appears to be destroyed and the DNA structure seems to be similar to that in DNA solution.

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DNA, ViralHot TemperatureMathematicsNucleic Acid ConformationScattering, RadiationSpectrophotometryT-PhagesX-RaysJournal Article

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A Fekete, G Rontó, L A Feigin, V V Tikhonychev, K Módos. 1982. Temperature dependent structural changes of intraphage T7 DNA.. https://doi.org/10.1007/bf00536011

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