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A crystallographic map of the transition from B-DNA to A-DNA.

ABSTRACT: The transition between B- and A-DNA was first observed nearly 50 years ago. We have now mapped this transformation through a set of single-crystal structures of the sequence d(GGCGCC)2, with various intermediates being trapped by methylating or brominating the cytosine bases. The resulting pathway progresses through 13 conformational steps, with a composite structure that pairs A-nucleotides with complementary B-nucleotides serving as a distinct transition intermediate. The details of each step in the conversion of B- to A-DNA are thus revealed at the atomic level, placing intermediates for this and other sequences in the context of a common pathway.

SUBMITTER: Vargason JM

PROVIDER: S-EPMC34657 | biostudies-literature | 2001 Jun

REPOSITORIES: biostudies-literature

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A crystallographic map of the transition from B-DNA to A-DNA.

Vargason J M JM Henderson K K Ho P S PS

Proceedings of the National Academy of Sciences of the United States of America 20010605 13

The transition between B- and A-DNA was first observed nearly 50 years ago. We have now mapped this transformation through a set of single-crystal structures of the sequence d(GGCGCC)2, with various intermediates being trapped by methylating or brominating the cytosine bases. The resulting pathway progresses through 13 conformational steps, with a composite structure that pairs A-nucleotides with complementary B-nucleotides serving as a distinct transition intermediate. The details of each step ...[more]

PMID: 11390969

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