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DNA polymerase V kinetics support the instructive nature of an oxidized abasic lesion in Escherichia coli.

ABSTRACT: Translesion synthesis past an oxidized abasic site, 2-deoxyribonolactone, in Escherichia coli results in high levels of dG incorporation and is dependent upon DNA polymerase V (Pol V). Kinetic experiments performed here affirm that Pol V preferentially incorporates dG opposite 2-deoxyribonolactone (L). Pol V discriminates between dG and dA on the basis of the apparent KD, suggesting that L provides instructive structural information to the enzyme despite lacking a Watson-Crick base.

SUBMITTER: Bajacan JE

PROVIDER: S-EPMC3817503 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature

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DNA polymerase V kinetics support the instructive nature of an oxidized abasic lesion in Escherichia coli.

Bajacan John Ernest V JE Greenberg Marc M MM

Biochemistry 20130909 37

Translesion synthesis past an oxidized abasic site, 2-deoxyribonolactone, in Escherichia coli results in high levels of dG incorporation and is dependent upon DNA polymerase V (Pol V). Kinetic experiments performed here affirm that Pol V preferentially incorporates dG opposite 2-deoxyribonolactone (L). Pol V discriminates between dG and dA on the basis of the apparent KD, suggesting that L provides instructive structural information to the enzyme despite lacking a Watson-Crick base. ...[more]

PMID: 24015801

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