The crystal structure of a hexameric DNA fragment with the sequence d(TGCGCA)(2) has been solved and refined at 293 K at a resolution of 1.64 A. The molecule adopts a left-handed Z-type helical conformation which is common in alternating pyrimidine-purine sequences. The presence of A.T base pairs at the two terminals does not perturb the structure to any great degree. However, several sequence-specific microstructural changes are noticeable. The structure of the identical sequence determined at 120 K involving somewhat different crystallization conditions has been reported previously [Harper et al. (1998), Acta Cryst. D54, 1273-1284]. A comparison of the present structure with that at low temperature and with that of d(CGCGCG)(2) shows that the effect of the change in sequence is greater than the combined effect of changes in temperature and environment.
Structure of d(TGCGCA)2 at 293 K: comparison of the effects of sequence and temperature.,Thiyagarajan S, Satheesh Kumar P, Rajan SS, Gautham N Acta Crystallogr D Biol Crystallogr. 2002 Aug;58(Pt 8):1381-4. Epub 2002, Jul 20. PMID:12136163[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
↑ Thiyagarajan S, Satheesh Kumar P, Rajan SS, Gautham N. Structure of d(TGCGCA)2 at 293 K: comparison of the effects of sequence and temperature. Acta Crystallogr D Biol Crystallogr. 2002 Aug;58(Pt 8):1381-4. Epub 2002, Jul 20. PMID:12136163
