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arXiv · 1404.0307

DNA polymerase V activity is autoregulated by a novel intrinsic DNA-dependent ATPase

Abstract

Escherichia coli DNA polymerase V (pol V), a heterotrimeric complex composed of UmuD'2C, is marginally active. ATP and RecA play essential roles in the activation of pol V for DNA synthesis including translesion synthesis (TLS). We have established three features of the roles of ATP and RecA. 1) RecA-activated DNA polymerase V (pol V Mut), is a DNA-dependent ATPase; 2) bound ATP is required for DNA synthesis; 3) pol V Mut function is regulated by ATP, with ATP required to bind primer/template (p/t) DNA and ATP hydrolysis triggering dissociation from the DNA. Pol V Mut formed with an ATPase-deficient RecA E38K/K72R mutant hydrolyzes ATP rapidly, establishing the DNA-dependent ATPase as an intrinsic property of pol V Mut distinct from the ATP hydrolytic activity of RecA when bound to single-stranded (ss)DNA as a nucleoprotein filament (RecA*). No similar ATPase activity or autoregulatory mechanism has previously been found for a DNA polymerase.

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Aysen L Erdem, Malgorzata Jaszczur, Jeffrey G Bertram, Roger Woodgate, Michael M Cox, Myron F Goodman. 2014-04-01. DNA polymerase V activity is autoregulated by a novel intrinsic DNA-dependent ATPase. https://arxiv.org/abs/1404.0307

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