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The bridge helix coordinates movements of modules in RNA polymerase.

ABSTRACT: The RNA polymerase 'bridge helix' is a metastable ?-helix that spans the leading edge of the enzyme active-site cleft. A new study published in BMC Biology reveals surprising tolerance to helix-disrupting changes in a region previously thought crucial for translocation, and suggests roles for two hinge-like segments of the bridge helix in coordinating modules that move during the nucleotide-addition cycle.

SUBMITTER: Hein PP

PROVIDER: S-EPMC2993669 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature

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The bridge helix coordinates movements of modules in RNA polymerase.

Hein Pyae P PP Landick Robert R

BMC biology 20101129

The RNA polymerase 'bridge helix' is a metastable α-helix that spans the leading edge of the enzyme active-site cleft. A new study published in BMC Biology reveals surprising tolerance to helix-disrupting changes in a region previously thought crucial for translocation, and suggests roles for two hinge-like segments of the bridge helix in coordinating modules that move during the nucleotide-addition cycle. ...[more]

PMID: 21114873

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