%0 Journal Article
%T A New Histone Structure Which Binds DNA at Its Eight Subunit N-Termini
%A Ken Biegeleisen
%J Open Access Library Journal
%V 3
%N 2
%P 1-20
%@ 2333-9721
%D 2016
%I Open Access Library
%R 10.4236/oalib.1102386
%X A new model for the nucleosome is presented. The histone octamer core is
unchanged, but the location of the DNA is different. Since the highest number,
and highest concentration of positively- charged amino acid residues is located
not in the ¡°superhelical ramp¡± of the octamer core, but rather in the domain of
the eight histone subunit N-termini collectively, the DNA is therefore placed
there. The role models for the protein and DNA structures in the N-terminal
domain are taken from the comparable role models for protein and DNA in the
protamine-DNA complex in sperm cells. The histone subunit N-termini are each
modeled as beta-strands, with psi/phi values of approximately  /©�130.5¡ã
respectively, which gives a straight chain. The DNA is modeled according to the
¡°straight ladder¡± model of Tai Te Wu. Each DNA phosphate group is bound to a
lysine or arginine residue of histone by a 3 A salt bridge. The new model lends
itself so readily to further models of higher-order chromatin structure that
the problem shifts entirely, from one of deducing any higher-order structure at
all, to one of distinguishing between several models which compete for our
attention.
%K Histone
%K Octamer
%K Nucleosome
%K Protamine
%K Helix
%U http://www.oalib.com/paper/4654122