2016/02/12 by Shimin Jiang, Akihiro Narita, David Popp +8 · 1 citation
Environmental Science · Biochemistry, Genetics and Molecular Biology · #Bacteriophages and microbial interactions #Bacterial Genetics and Biotechnology #RNA and protein synthesis mechanisms
paper · pdf · doi:10.1073/pnas.1600129113
openalex publication_date 2016/02/12 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/22
Here we report the discovery of a bacterial DNA-segregating actin-like protein (BtParM) from Bacillus thuringiensis, which forms novel antiparallel, two-stranded, supercoiled, nonpolar helical filaments, as determined by electron microscopy. The BtParM filament features of supercoiling and forming antiparallel double-strands are unique within the actin fold superfamily, and entirely different to the straight, double-stranded, polar helical filaments of all other known ParMs and of eukaryotic F-actin. The BtParM polymers show dynamic assembly and subsequent disassembly in the presence of ATP. BtParR, the DNA-BtParM linking protein, stimulated ATP hydrolysis/phosphate release by BtParM and paired two supercoiled BtParM filaments to form a cylinder, comprised of four strands with inner and outer diameters of 57 Å and 145 Å, respectively. Thus, in this prokaryote, the actin fold has evolved to produce a filament system with comparable features to the eukaryotic chromosome-segregating microtubule.