The DNA transporter ComEC has metal-dependent nuclease activity that is important for natural transformation.
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ABSTRACT:
SUBMITTER: Silale A
PROVIDER: S-EPMC8579336 | biostudies-literature | 2021 Aug
REPOSITORIES: biostudies-literature
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The DNA transporter ComEC has metal-dependent nuclease activity that is important for natural transformation.
Silale Augustinas A Lea Susan M SM Berks Ben C BC
Molecular microbiology 20210604 2
In the process of natural transformation bacteria import extracellular DNA molecules for integration into their genome. One strand of the incoming DNA molecule is degraded, whereas the remaining strand is transported across the cytoplasmic membrane. The DNA transport channel is provided by the protein ComEC. Many ComEC proteins have an extracellular C-terminal domain (CTD) with homology to the metallo-β-lactamase fold. Here we show that this CTD binds Mn<sup>2+</sup> ions and exhibits Mn<sup>2+< ...[more]
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