A novel mechanism of sugar selection utilized by a human X-family DNA polymerase.
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ABSTRACT:
SUBMITTER: Brown JA
PROVIDER: S-EPMC2814876 | biostudies-literature | 2010 Jan
REPOSITORIES: biostudies-literature
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A novel mechanism of sugar selection utilized by a human X-family DNA polymerase.
Brown Jessica A JA Fiala Kevin A KA Fowler Jason D JD Sherrer Shanen M SM Newmister Sean A SA Duym Wade W WW Suo Zucai Z
Journal of molecular biology 20091106 2
During DNA synthesis, most DNA polymerases and reverse transcriptases select against ribonucleotides via a steric clash between the ribose 2'-hydroxyl group and the bulky side chain of an active-site residue. In this study, we demonstrated that human DNA polymerase lambda used a novel sugar selection mechanism to discriminate against ribonucleotides, whereby the ribose 2'-hydroxyl group was excluded mostly by a backbone segment and slightly by the side chain of Y505. Such steric clash was furthe ...[more]
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