From Proteopedia

proteopedia linkproteopedia link

spinqualitylabelsall models PDB ID 1mwm Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image
, resolution 2.0Å
Ligands:	and
Coordinates:	save as pdb, mmCIF, xml

ParM from plasmid R1 ADP form

Overview

It was the general belief that DNA partitioning in prokaryotes is independent of a cytoskeletal structure, which in eukaryotic cells is indispensable for DNA segregation. Recently, however, immunofluorescence microscopy revealed highly dynamic, filamentous structures along the longitudinal axis of Escherichia coli formed by ParM, a plasmid-encoded protein required for accurate segregation of low-copy-number plasmid R1. We show here that ParM polymerizes into double helical protofilaments with a longitudinal repeat similar to filamentous actin (F-actin) and MreB filaments that maintain the cell shape of non-spherical bacteria. The crystal structure of ParM with and without ADP demonstrates that it is a member of the actin family of proteins and shows a domain movement of 25 degrees upon nucleotide binding. Furthermore, the crystal structure of ParM reveals major differences in the protofilament interface compared with F-actin, despite the similar arrangement of the subunits within the filaments. Thus, there is now evidence for cytoskeletal structures, formed by actin-like filaments that are involved in plasmid partitioning in E.coli.

About this Structure

1MWM is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.

Reference

F-actin-like filaments formed by plasmid segregation protein ParM., van den Ent F, Moller-Jensen J, Amos LA, Gerdes K, Lowe J, EMBO J. 2002 Dec 16;21(24):6935-43. PMID:12486014

Page seeded by OCA on Sun Mar 23 12:49:21 2008