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Title: Metagenome mining and functional analysis reveal oxidized guanine DNA repair at the Lost City Hydrothermal Field
The GO DNA repair system protects against GC → TA mutations by finding and removing oxidized guanine. The system is mechanistically well understood but its origins are unknown. We searched metagenomes and abundantly found the genes encoding GO DNA repair at the Lost City Hydrothermal Field (LCHF). We recombinantly expressed the final enzyme in the system to show MutY homologs function to suppress mutations. Microbes at the LCHF thrive without sunlight, fueled by the products of geochemical transformations of seafloor rocks, under conditions believed to resemble a young Earth. High levels of the reductant H2and low levels of O2in this environment raise the question, why are resident microbes equipped to repair damage caused by oxidative stress? MutY genes could be assigned to metagenome-assembled genomes (MAGs), and thereby associate GO DNA repair with metabolic pathways that generate reactive oxygen, nitrogen and sulfur species. Our results indicate that cell-based life was under evolutionary pressure to cope with oxidized guanine well before O2levels rose following the great oxidation event.  more » « less
Award ID(s):
2204229 1905249
PAR ID:
10608478
Author(s) / Creator(s):
; ; ; ; ;
Editor(s):
Gupta, Pramodkumar Pyarelal
Publisher / Repository:
Public Library of Science (PLOS)
Date Published:
Journal Name:
PLOS ONE
Volume:
19
Issue:
5
ISSN:
1932-6203
Page Range / eLocation ID:
e0284642
Subject(s) / Keyword(s):
DNA repair molecular evolution great oxidation event BER base excision repair MutY
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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