Visualizing the dynamic polymerization of the bacterial actin-like cytoskeleton for magnetic organelle positioning.

ABSTRACT: MamK, an actin-like protein conserved in magnetotactic bacteria, functions as a cytoskeletal element that positions the magnetosome, a bacterial geomagnetic sensor organelle. Specifically, MamK polymerizes into filaments associated with the magnetosome chain within each cell. The dynamics of these filaments are fundamental to magnetosome organelle positioning. However, the dynamic nature of the polymerized MamK filaments has not been characterized at the molecular level under physiological conditions. In this study, we used high-speed atomic force microscopy (AFM) to characterize the dynamic MamK polymerization process. MamK polymerized as double-helical filaments with a half-helical pitch distance of 41.3 ± 5.1 nm and a filament diameter of 6.3 ± 0.5 nm. The polymerizing MamK filaments el

SUBMITTER: Pan Y 

PROVIDER: S-EPMC12738573 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature