Supercoiled DNA: Structure
نویسنده
چکیده
Supercoiling is introduced into DNAmolecules when the double helix is twisted around its own axis in three-dimensional space. Generally, DNAmolecules are negatively supercoiled inside cells, although the level of supercoiling is not equal throughout the genome and many supercoils may be constrained by bound proteins. Supercoiling increases the free energy of DNA and influences DNA metabolism by promoting or hindering specific enzymatic processes.
منابع مشابه
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Supercoiled DNA is the relevant substrate for a large number of DNA transactions and has additionally been found to be a favorable form for delivering DNA and protein-DNA complexes to cells. We report here a facile method for stoichiometrically incorporating several different modifications at multiple, specific, and widely spaced sites in supercoiled DNA. The method is based upon generating an ...
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