High accuracy (fidelity) of DNA replication is important for cells to preserve the genetic identity and to prevent the accumulation of deleterious mutations. The error rate during DNA replication is as low as 10(-9) to 10(-11) errors per base pair. How this low level is achieved is an issue of major interest. This review is concerned with the mechanisms underlying the fidelity of the chromosomal replication in the model system Escherichia coli by DNA polymerase III holoenzyme, with further emphasis on participation of the other, accessory DNA polymerases, of which E. coli contains four (Pols I, II, IV, and V). Detailed genetic analysis of mutation rates revealed that (1) Pol II has an important role as a back-up proofreader for Pol III, (2) Pols IV and V do not normally contribute significantly to replication fidelity, but can readily do so under conditions of elevated expression, (3) participation of Pols IV and V, in contrast to that of Pol II, is specific to the lagging strand, and (4) Pol I also makes a lagging-strand-specific fidelity contribution, limited, however, to the faithful filling of the Okazaki fragment gaps. The fidelity role of the Pol III τ subunit is also reviewed.

中文翻译：

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大肠杆菌中的 DNA 复制保真度：多 DNA 聚合酶事件。

DNA 复制的高精度（保真度）对于细胞保持遗传特性和防止有害突变的积累非常重要。DNA 复制过程中的错误率低至每个碱基对 10(-9) 到 10(-11) 个错误。如何达到如此低的水平是一个重要的问题。本综述涉及 DNA 聚合酶 III 全酶在模型系统大肠杆菌中染色体复制保真度的机制，进一步强调了其他辅助 DNA 聚合酶的参与，其中大肠杆菌包含四种（Pols I， II、IV 和 V)。突变率的详细遗传分析表明 (1) Pol II 作为 Pol III 的后备校对器具有重要作用，(2) Pols IV 和 V 通常对复制保真度没有显着贡献，但在表达升高的条件下可以很容易地做到这一点，（3）与 Pol II 相比，Pols IV 和 V 的参与是滞后链特异性的，并且（4）Pol I 也使滞后链特异性然而，保真度的贡献仅限于忠实地填补冈崎片段的空白。还审查了 Pol III τ 亚基的保真度作用。