DNA glycosylases provide antiviral defence in prokaryotes.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 38632404.
- Also identified by DOI 10.1038/s41586-024-07329-9 and PMC identifier 11078745.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Bacteria have adapted to phage predation by evolving a vast assortment of defence systems<sup>1</sup>. Although anti-phage immunity genes can be identified using bioinformatic tools, the discovery of novel systems is restricted to the available prokaryotic sequence data<sup>2</sup>. Here, to overcome this limitation, we infected Escherichia coli carrying a soil metagenomic DNA library<sup>3</sup> with the lytic coliphage T4 to isolate clones carrying protective genes. Following this approach, we identified Brig1, a DNA glycosylase that excises α-glucosyl-hydroxymethylcytosine nucleobases from the bacteriophage T4 genome to generate abasic sites and inhibit viral replication. Brig1 homologues that provide immunity against T-even phages are present in multiple phage defence loci across distinct clades of bacteria. Our study highlights the benefits of screening unsequenced DNA and reveals prokaryotic DNA glycosylases as important players in the bacteria-phage arms race.
Medical subject headings
- Bacteria
- Bacteriophage T4
- DNA Glycosylases