Crystal structure of Z-DNA without an alternating purine-pyrimidine sequence.
AUTOR(ES)
Wang, A H
RESUMO
In left-handed Z-DNA, consecutive nucleotides along the chain alternate in the syn and anti conformations. Purine residues form the syn conformation readily and up to now all Z-DNA crystal structures have sequences of alternating purines and pyrimidines. However, we find that d(C-G-A-T-C-G) with the cytosines brominated or methylated on C-5 crystallizes as Z-DNA. The structure reveals thymines in syn and adenines in anti conformations. This suggests that Z-DNA may occur in sequences other than those with alternating purine-pyrimidine sequence.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=397835Documentos Relacionados
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