Karthik S, Thirugnanasambandam A, Mandal PK, Gautham N. Crystal structure of d(CCGGGGTACCCCGG)
2 at 1.4 Å resolution.
Acta Crystallogr F Struct Biol Commun 2017;
73:259-265. [PMID:
28471357 PMCID:
PMC5417315 DOI:
10.1107/s2053230x17004770]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Accepted: 03/27/2017] [Indexed: 11/10/2022] Open
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.
Collapse