Questions tagged [supercoiling]
Supercoiling is a form of DNA in which the double helix is further twisted about itself, forming a tightly coiled structure.
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DNA topology Linking number vs twist?
Background
Linking number: the linking number represents the number of times that
each curve winds around the other.
Twist, called "twist", refers to the number of Watson-Crick twists in the
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Reason behind formation of positive supercoils during DNA replication/ transcription
When a twist is unwound without cutting the DNA strands or is removed by cutting the strand(s) and resealing, negative supercoils are introduced in the DNA.
From Cell and Molecular Biology -Karp
But ...
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Why is compensatory negative supercoiling generated in a positively supercoiling ccDNA?
I was reading DNA replication in E.coli in Lehninger Principles of Biochemistry 6th Ed. and stumbled upon the following --
The tight right handed wrapping of DNA around DnaA oligomeric complex ...
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What is positive and negative supercoiling?
Is the following correct?
Positive supercoiling = the coiling of DNA helix (B-DNA) on itself during intesified coiling of the two DNA stands in right handed direction
negative supercoiling = the ...
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A little help understanding DNA supercoiling
I am studying molecular biology from Lewin's Genes XII and got confused in the supercoiling topic. Since then I read from several other sources and so far understood the following. However, I can't ...
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Why do most organisms have negative supercoiled DNA?
It has been observed that in nature most organisms have negative supercoiled DNA and that few organisms have positive supercoiled DNA. Some of the organisms that have the positive supercoiled DNA live ...
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Why does underwinding create topological strain of DNA?
I am currently studying the supercoiling of DNA. I understand why overwinding would create additional strain for two attached strands of DNA, but I really don't get why underwinding would create ...
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Understanding DNA supercoiling
While trying to understand DNA supercoiling, I came across these lines in the book Genetics by Ursula Goodenough :
All natural DNA is superhelical. The axis of the duplex itself follows
a helical ...
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