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Mispairs with Watson-Crick base-pair geometry observed in ternary complexes of an RB69 DNA polymerase variant.

ABSTRACT: Recent structures of DNA polymerase complexes with dGMPCPP/dT and dCTP/dA mispairs at the insertion site have shown that they adopt Watson-Crick geometry in the presence of Mn(2+) indicating that the tautomeric or ionization state of the base has changed. To see whether the tautomeric or ionization state of base-pair could be affected by its microenvironment, we determined 10 structures of an RB69 DNA polymerase quadruple mutant with dG/dT or dT/dG mispairs at position n-1 to n-5 of the Primer/Template duplex. Different shapes of the mispairs, including Watson-Crick geometry, have been observed, strongly suggesting that the local environment of base-pairs plays an important role in their tautomeric or ionization states.

SUBMITTER: Xia S

PROVIDER: S-EPMC3970900 | biostudies-literature | 2014 Apr

REPOSITORIES: biostudies-literature

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Mispairs with Watson-Crick base-pair geometry observed in ternary complexes of an RB69 DNA polymerase variant.

Xia Shuangluo S Konigsberg William H WH

Protein science : a publication of the Protein Society 20140401 4

Recent structures of DNA polymerase complexes with dGMPCPP/dT and dCTP/dA mispairs at the insertion site have shown that they adopt Watson-Crick geometry in the presence of Mn(2+) indicating that the tautomeric or ionization state of the base has changed. To see whether the tautomeric or ionization state of base-pair could be affected by its microenvironment, we determined 10 structures of an RB69 DNA polymerase quadruple mutant with dG/dT or dT/dG mispairs at position n-1 to n-5 of the Primer/T ...[more]

PMID: 24458997

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