B Family DNA Polymerases Asymmetrically Recognize Pyrimidines and Purines

0364221 - ÚOCHB 2012 RIV US eng J - Journal Article
Lund, T. J. - Cavanaugh, N. A. - Joubert, Nicolas - Urban, M. - Patro, J. N. - Hocek, Michal - Kuchta, R. D.
B Family DNA Polymerases Asymmetrically Recognize Pyrimidines and Purines.
Biochemistry. Roč. 50, č. 33 (2011), s. 7243-7250. ISSN 0006-2960
R&D Projects: GA MŠMT LC512; GA AV ČR IAA400550902
Institutional research plan: CEZ:AV0Z40550506
Keywords : active-site tightness * genetic alphabet * deoxynucleoside * phosphoramidites
Subject RIV: CC - Organic Chemistry
Impact factor: 3.422, year: 2011

We utilized a series of modified pyrimidine analogues to determine the mechanism used by human DNA polymerase α and herpes simplex virus I DNA polymerase to polymerize pyrimidine dNTPs. Removing O2 of a pyrimidine dNTP vastly decreased incorporation by these enzymes and also compromised fidelity in the case of C analogues, while removing O2 from the templating base had more modest effects. Removing the Watson-Crick hydrogen bonding groups greatly impaired polymerization. The Watson-Crick hydrogen bonding plays an important role in enhancing correct dNTP polymerization, but are not essential for preventing misincorporation. These studies also indicate that DNA polymerases recognize bases extremely asymmetrically, both in terms of whether they are a purine or pyrimidine and whether they are in the template or are the incoming dNTP. The mechanistic implications of these results regarding how polymerases discriminate between right and wrong dNTPs are discussed.
Permanent Link: http://hdl.handle.net/11104/0199756