Abstract
A new group of error-prone DNA polymerases overcomes the blockage posed to normal DNA replication by damaged template bases, suggesting an active site with a loose, flexible pocket that accommodates aberrant DNA structures. We have determined a 2.8 A resolution crystal structure of the Sulfolobus solfataricus Dbh protein, a DNA translesion polymerase closely related to Escherichia coli DNA polymerase IV and human polymerase kappa. A high error rate is observed for the Dbh polymerase in a range of 10(-2)-10(-3) for all 12 base substitution mispairs. The crystal structure of Dbh reveals an overall architecture resembling other DNA polymerases but has unique features that are likely to contribute to error-prone synthesis, including -1 frameshifting mutations.
Publication types
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Research Support, U.S. Gov't, Non-P.H.S.
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Research Support, U.S. Gov't, P.H.S.
MeSH terms
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Amino Acid Sequence
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Archaeal Proteins*
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Bacterial Proteins / chemistry*
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Bacterial Proteins / metabolism*
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Catalysis
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Conserved Sequence
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Crystallography, X-Ray
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DNA Polymerase beta / chemistry*
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DNA-Directed DNA Polymerase*
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Escherichia coli Proteins*
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Humans
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Kinetics
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Models, Molecular
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Molecular Sequence Data
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Mutagenesis*
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Protein Structure, Tertiary
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Proteins / chemistry
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Sequence Alignment
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Sequence Homology, Amino Acid*
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Sulfolobus / enzymology*
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Taq Polymerase / metabolism
Substances
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Archaeal Proteins
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Bacterial Proteins
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DinB protein, E coli
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Escherichia coli Proteins
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Proteins
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Dbh protein, Sulfolobus solfataricus
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Taq Polymerase
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DNA Polymerase beta
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DNA-Directed DNA Polymerase
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POLK protein, human