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Title: An Extracellular, Ca 2+ ‐Activated Nuclease ( EcnA ) Mediates Transformation in a Naturally Competent Archaeon
ABSTRACT Transformation, the uptake of DNA directly from the environment, is a major driver of gene flow in microbial populations. In bacteria, DNA uptake requires a nuclease that processes dsDNA to ssDNA, which is subsequently transferred into the cell and incorporated into the genome. However, the process of DNA uptake in archaea is still unknown. Previously, we cataloged genes essential to natural transformation inMethanococcus maripaludis, but few homologs of bacterial transformation‐associated genes were identified. Here, we characterize one gene, MMJJ_16440 (named here asecnA), to be an extracellular nuclease. We show that EcnA is Ca2+‐activated, present on the cell surface, and essential for transformation. While EcnA can degrade several forms of DNA, the highest activity was observed with ssDNA as a substrate. Activity was also observed with circular dsDNA, suggesting that EcnA is an endonuclease. This is the first biochemical characterization of a transformation‐associated protein in a member of the archaeal domain and suggests that both archaeal and bacterial transformation initiate in an analogous fashion.  more » « less
Award ID(s):
2148165
PAR ID:
10615854
Author(s) / Creator(s):
; ; ;
Corporate Creator(s):
Publisher / Repository:
Molecular Microbiology
Date Published:
Journal Name:
Molecular Microbiology
Volume:
122
Issue:
4
ISSN:
0950-382X
Page Range / eLocation ID:
477 to 490
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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