Functional insights into Solo-Cas4 in <i>Methanosarcina mazei</i> Go1.

ABSTRACT: Solo-Cas4 homologs are Cas4-family proteins found outside of canonical CRISPR-Cas operons. Here, we present the biochemical characterization of Solo-Cas4 from Methanosarcina mazei Gö1. We found significantly upregulated solo-cas4 transcript levels during stationary phase, while remaining constant under oxygen exposure, temperature shifts, high salt conditions or virus challenge. Heterologously expressed as a SUMO-fusion, the purified tag-free protein displays an absorption peak at 420 nm, indicative of a [4Fe-4S]-cluster​. Size-exclusion-chromatography revealed that Solo-Cas4 forms a higher oligomeric complex, with an apparent molecular mass of 318 kDa. In vitro nuclease activity assays demonstrated that Solo-Cas4 cleaves metal-dependent linear dsDNA, with highest clea

SUBMITTER: Rentz L 

PROVIDER: S-EPMC12501428 | biostudies-literature | 2025

REPOSITORIES: biostudies-literature