DNA Supercoil

DNA Supercoil

DNA supercoiling refers to the over- or under-winding of a DNA strand, and is an expression of the strain on that strand. Supercoiling is important in a number of biological processes, such as compacting DNA. Additionally, certain enzymes such as topoisomerases are able to change DNA topology to facilitate functions such as DNA replication or transcription. Mathematical expressions are used to describe supercoiling by comparing different coiled states to relaxed B-form DNA.

As a general rule, the DNA of most organisms is negatively supercoiled.

Read more about DNA Supercoil:  Role of Supercoiling, Occurrence of DNA Supercoiling, Mathematical Description, Effects On Sedimentation Coefficient

Other articles related to "dna supercoil, dna":

DNA Supercoil - Effects On Sedimentation Coefficient
... The topological properties of circular DNA are complex, and only a brief introduction can be presented here ... properties are invariably explained in terms of a helical model for DNA, because the majority of scientists continue to believe that no other structure is possible ... When the sedimentation coefficient, s, of circular DNA is ascertained over a large range of pH, the following curves are seen ...

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