Biotechnology and Biological Sciences Research Council (BBSRC)
BB/X01/097X/1
英国
引用
ジャーナル: Nat Commun / 年: 2025 タイトル: Molecular basis of foreign DNA recognition by BREX anti-phage immunity system. 著者: Alena Drobiazko / Myfanwy C Adams / Mikhail Skutel / Kristina Potekhina / Oksana Kotovskaya / Anna Trofimova / Mikhail Matlashov / Daria Yatselenko / Karen L Maxwell / Tim R Blower / ...著者: Alena Drobiazko / Myfanwy C Adams / Mikhail Skutel / Kristina Potekhina / Oksana Kotovskaya / Anna Trofimova / Mikhail Matlashov / Daria Yatselenko / Karen L Maxwell / Tim R Blower / Konstantin Severinov / Dmitry Ghilarov / Artem Isaev / 要旨: Anti-phage systems of the BREX (BacteRiophage EXclusion) superfamily rely on site-specific epigenetic DNA methylation to discriminate between the host and invading DNA. We demonstrate that in Type I ...Anti-phage systems of the BREX (BacteRiophage EXclusion) superfamily rely on site-specific epigenetic DNA methylation to discriminate between the host and invading DNA. We demonstrate that in Type I BREX systems, defense and methylation require BREX site DNA binding by the BrxX (PglX) methyltransferase employing S-adenosyl methionine as a cofactor. We determined 2.2-Å cryoEM structure of Escherichia coli BrxX bound to target dsDNA revealing molecular details of BREX DNA recognition. Structure-guided engineering of BrxX expands its DNA specificity and dramatically enhances phage defense. We show that BrxX alone does not methylate DNA, and BREX activity requires an assembly of a supramolecular BrxBCXZ immune complex. Finally, we present a cryoEM structure of BrxX bound to a phage-encoded inhibitor Ocr that sequesters BrxX in an inactive dimeric form. We propose that BrxX-mediated foreign DNA sensing is a necessary first step in activation of BREX defense.