Department of Biology, Portland State University, Portland, Oregon, USA
Department of Biology, Portland State University, Portland, Oregon, USA.
J Bacteriol. 2019 Nov 20;201(24). doi: 10.1128/JB.00426-19. Print 2019 Dec 15.
Divalent metals such as iron and manganese play an important role in the cellular response to oxidative challenges and are required as cofactors by many enzymes. However, how these metals affect replication after oxidative challenge is not known. Here, we show that replication in is inhibited following a challenge with hydrogen peroxide and requires manganese for the rapid recovery of DNA synthesis. We show that the manganese-dependent recovery of DNA synthesis occurs independent of lesion repair, modestly improves cell survival, and is associated with elevated rates of mutagenesis. The Mn-dependent mutagenesis involves both replicative and translesion polymerases and requires prior disruption by HO to occur. Taking these findings together, we propose that replication in is likely to utilize an iron-dependent enzyme(s) that becomes oxidized and inactivated during oxidative challenges. The data suggest that manganese remetallates these or alternative enzymes to allow genomic DNA replication to resume, although with reduced fidelity. Iron and manganese play important roles in how cell's cope with oxygen stress. However, how these metals affect the ability of cells to replicate after oxidative challenges is not known. Here, we show that replication in is inhibited following a challenge with hydrogen peroxide and requires manganese for the rapid recovery of DNA synthesis. The manganese-dependent recovery of DNA synthesis occurs independently of lesion repair and modestly improves survival, but it also increases the mutation rate in cells. The results imply that replication in is likely to utilize an iron-dependent enzyme(s) that becomes oxidized and inactivated during oxidative challenges. We propose that manganese remetallates these or alternative enzymes to allow genomic DNA replication to resume, although with reduced fidelity.
二价金属,如铁和锰,在细胞对氧化应激的反应中发挥重要作用,并且是许多酶的辅助因子。然而,这些金属如何影响氧化应激后的复制尚不清楚。在这里,我们表明,在过氧化氢的挑战下, 的复制受到抑制,并且需要锰才能快速恢复 DNA 合成。我们表明,锰依赖性 DNA 合成的恢复独立于损伤修复发生,适度提高细胞存活率,并与更高的突变率相关。锰依赖性突变涉及复制和跨损伤聚合酶,并且需要 HO 预先破坏才能发生。综合这些发现,我们提出, 在氧化应激下,可能利用一种铁依赖性酶(s),该酶在氧化应激下会被氧化和失活。数据表明,锰重新螯合这些酶或替代酶,以允许基因组 DNA 复制恢复,尽管保真度降低。铁和锰在细胞应对氧应激方面发挥重要作用。然而,这些金属如何影响细胞在氧化应激后复制的能力尚不清楚。在这里,我们表明,在过氧化氢的挑战下, 的复制受到抑制,并且需要锰才能快速恢复 DNA 合成。锰依赖性 DNA 合成的恢复独立于损伤修复发生,适度提高生存能力,但也会增加细胞中的突变率。结果表明, 在氧化应激下,可能利用一种铁依赖性酶(s),该酶在氧化应激下会被氧化和失活。我们提出,锰重新螯合这些酶或替代酶,以允许基因组 DNA 复制恢复,尽管保真度降低。