DNA supercoiling enhances DNA condensation by ParB proteins.

ABSTRACT: The ParABS system plays a critical role in bacterial chromosome segregation. The key component of this system, ParB, loads and spreads along DNA to form a local protein-DNA condensate known as a partition complex. As bacterial chromosomes are heavily supercoiled due to the continuous action of RNA polymerases, topoisomerases and nucleoid-associated proteins, it is important to study the impact of DNA supercoiling on the ParB-DNA partition complex formation. Here, we use an in-vitro single-molecule assay to visualize ParB on supercoiled DNA. Unlike most DNA-binding proteins, individual ParB proteins are found to not pin plectonemes on supercoiled DNA, but freely diffuse along supercoiled DNA. We find that DNA supercoiling enhances ParB-DNA condensation, which initiates at lower ParB concent

SUBMITTER: Martin-Gonzalez A 

PROVIDER: S-EPMC11602141 | biostudies-literature | 2024 Nov

REPOSITORIES: biostudies-literature