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Published on: August 9, 2011
Crystal structures of disordered Z-type helices
S Karthik1, P K Mandal1, A Thirugnanasambandam1
1a Centre of Advanced Study in Crystallography and Biophysics , University of Madras, Guindy Campus , Chennai , Tamil Nadu , India.
Abstract:
The X-ray crystal structures of a decamer sequence d(CGCGTACGCG)2 and a tetradecamer sequence d(CGCGCGTACGCGCG)2 are presented here. Both sequences are alternating pyrimidine-purine repeat sequences and they form disordered, pseudo-continuous left handed Z-type helices. They demonstrate interesting variants of the 'bundles of columns of helices' mode of packing.
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