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PubMed · 8152368

Halobacterial megaplasmids are negatively supercoiled.

P López-García·J Antón·J P Abad·R Amils
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Abstract

Several covalently closed circular halobacterial megaplasmids (up to more than 500 kb) from different strains of Haloferax mediterranei, have been resolved by orthogonal-field alternating gel electrophoresis (OFAGE). These molecules seem to be negatively supercoiled in vivo, as deduced from the effect of intercalating agents affecting their topology and, therefore, their electrophoretic mobility. It has also been demonstrated that the topoisomerase II inhibitor novobiocin affects the native topological state of halobacterial megaplasmids impeding their migration in OFAGE under standard conditions for resolution of large supercoiled molecules.

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DNA, SuperhelicalElectrophoresisHalobacteriumNovobiocinNucleic Acid ConformationPlasmidsJournal ArticleResearch Support, Non-U.S. Gov't

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P López-García, J Antón, J P Abad, R Amils. 1994. Halobacterial megaplasmids are negatively supercoiled.. https://doi.org/10.1111/j.1365-2958.1994.tb00323.x

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