Mechanisms of Bacterial DNA Polymerase Replication and Fidelity

自60年前发现DNA的双螺旋结构以来，大量的动力学和结构数据阐明了DNA聚合酶用于实现高效和准确的DNA复制的许多机制。即便如此，我们的理解还远远不够完整，特别是因为现在已知许多不同的聚合酶是完成基因组复制所必需的。在这里，我们重点研究了来自细菌病原体金黄色葡萄球菌的两种聚合酶：必需c家族复制聚合酶和y家族翻译聚合酶。c家族聚合酶包括高度精确的PolC，它不能有效地复制受损的DNA，以及容易出错的DnaE，它启动RNA引物的DNA合成。y家族聚合酶能够复制受损的DNA，但非常容易出错。我们将使用动力学，结构和分子遗传学技术来确定这些聚合酶如何以高精度复制细菌基因组，但也会产生产生抗生素的突变

DESCRIPTION (provided by applicant): Since the discovery of the double-helical structure of DNA 60 years ago, a wealth of kinetic and structural data have illuminated many of the mechanisms DNA polymerases use to achieve efficient and accurate DNA replication. Even so, our understanding is far from complete, especially since many different polymerases are now known to be required for complete genome duplication. Here, we focus our research on two types of polymerases from the bacterial pathogen Staphylococcus aureus: the essential C-family replicative polymerases and the Y-family translesion polymerases. The C-family polymerases include the highly accurate PolC, which is unable to efficiently copy damaged DNA, and the error-prone DnaE, which initiates DNA synthesis from RNA primers. The Y-family polymerases are able to replicate damaged DNA but are highly error-prone. We will use kinetic, structural and molecular genetic techniques to determine how these polymerases replicate the bacterial genome with high accuracy overall, but also create mutations that give rise to antibiotic resistance. Since DNA replication is such a fundamental process, the research will have broad implications for other bacteria.