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1d29
From Proteopedia
CRYSTAL STRUCTURE ANALYSIS OF THE B-DNA DODECAMER CGTGAATTCACG
Overview
The crystal structure of the DNA dodecamer C-G-T-G-A-A-T-T-C-A-C-G has been determined at a resolution of 2.5 A, with a final R factor of 15.8% for 1475 nonzero reflections measured at 0 degrees C. The structure is isomorphous with that of the Drew dodecamer, with the space group P2(1)2(1)2(1) and cell dimensions of a = 24.94 A, b = 40.78 A, and c = 66.13 A. The asymmetric unit contains all 12 base pairs of the B-DNA double helix and 36 water molecules. The structure of C-G-T-G-A-A-T-T-C-A-C-G is very similar to that of C-G-C-G-A-A-T-T-C-G-C-G, with no major alterations in helix parameters. Water peaks in the refined structure appear to represent a selection of peaks that were observed in the Drew dodecamer. The minor-groove spine of hydration at 2.5 A is fragmentary, but as Narendra et al. (1991) [Biochemistry (following paper in this issue)] have observed, lowering the temperature leads to a more complete representation of the spine.
About this Structure
Full crystallographic information is available from OCA.
Reference
Crystal structure analysis of the B-DNA dodecamer CGTGAATTCACG., Larsen TA, Kopka ML, Dickerson RE, Biochemistry. 1991 May 7;30(18):4443-9. PMID:1850624 Page seeded by OCA on Fri May 2 13:22:02 2008
