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Crystal structure of d(CCGGGGTACCCCGG)2 at 1.4?A resolution.

ABSTRACT: The X-ray crystal structure of the DNA tetradecamer sequence d(CCGGGGTACCCCGG)2 is reported at 1.4?Å resolution in the tetragonal space group P41212. The sequence was designed to fold as a four-way junction. However, it forms an A-type double helix in the presence of barium chloride. The metal ion could not be identified in the electron-density map. The crystallographic asymmetric unit consists of one A-type double helix with 12 base pairs per turn, in contrast to 11 base pairs per turn for canonical A-DNA. A large number of solvent molecules have been identified in both the grooves of the duplex and around the backbone phosphate groups.

SUBMITTER: Karthik S

PROVIDER: S-EPMC5417315 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

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Crystal structure of d(CCGGGGTACCCCGG)2 at 1.4 Å resolution.

Karthik Selvam S Thirugnanasambandam Arunachalam A Mandal Pradeep Kumar PK Gautham Namasivayam N

Acta crystallographica. Section F, Structural biology communications 20170426 Pt 5

The X-ray crystal structure of the DNA tetradecamer sequence d(CCGGGGTACCCCGG)2 is reported at 1.4 Å resolution in the tetragonal space group P41212. The sequence was designed to fold as a four-way junction. However, it forms an A-type double helix in the presence of barium chloride. The metal ion could not be identified in the electron-density map. The crystallographic asymmetric unit consists of one A-type double helix with 12 base pairs per turn, in contrast t ...[more]

PMID: 28471357

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