%0 Journal Article
%T Helical Repeats of Left-Handed DNA
%A Youcheng Xu
%J Open Journal of Molecular and Integrative Physiology
%P 20-26
%@ 2162-2167
%D 2014
%I Scientific Research Publishing
%R 10.4236/ojmip.2014.42003
%X <span><span>DNA is generally assumed as a right-handed double helix and Z-DNA is a
special kind of left-handed DNA infrequently found in nature. However, the
finding of a zero linking number topoisomer supports a hypothesis that the two
strands of DNA are winding ambidextrously, rather than plectonemically. It logically
leads to a notion that the left-handed DNA is as common as right-handed DNA
and the amount of left-handed DNA in a positively supercoiled plasmid prevails
that of the right-handed DNA. In this report, the helical repeat of left-handed
DNA, 12 bp per turn, was determined by a new method. How the positively
supercoiled DNA was generated in hyperthermophiles and why their DNA can
withstand the extreme high temperature are answered from an alternative theory.</span></span>
%K Left-Handed DNA
%K Ambidextrous Double Helix
%K Linking Number
%K Positive Supercoiling
%K Hyperthermophiles
%U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=45978