191d
From Proteopedia
|
CRYSTAL STRUCTURE OF INTERCALATED FOUR-STRANDED D(C3T)
Overview
The crystal structure of d(C3T), solved at 1.4 A resolution, reveals that, the molecule forms a four-stranded intercalated complex. It consists of, two parallel-stranded duplexes, each of which is held together by, cytosine-protonated cytosine base pairs. The two duplexes are intercalated, with each other and have opposite strand orientation. The molecule has a, flat, lath-like appearance, and the covalently bonded cytosines have a, slow right-handed twist of 17.1 degrees. However, there is considerable, asymmetry. On one of the flat sides, the phosphate groups are rotated away, from the center of the molecule. They are held in this orientation by, bridging water molecules that bind the NH of cytosine and a phosphate, group of an opposite chain. There is also considerable microheterogeneity, in the structure. The cytosine hemiprotonation occurs even at pH 7 where, stable crystals form.
About this Structure
191D is a Protein complex structure of sequences from [1] with NA as ligand. Full crystallographic information is available from OCA.
Reference
Crystal structure of intercalated four-stranded d(C3T) at 1.4 A resolution., Kang CH, Berger I, Lockshin C, Ratliff R, Moyzis R, Rich A, Proc Natl Acad Sci U S A. 1994 Nov 22;91(24):11636-40. PMID:7972115
Page seeded by OCA on Sat Nov 24 22:11:25 2007
