Negative-stain electron microscopy of inside-out FtsZ rings reconstituted on artificial membrane tubules show ribbons of protofilaments.

ABSTRACT: FtsZ, the primary cytoskeletal element of the Z ring, which constricts to divide bacteria, assembles into short, one-stranded filaments in vitro. These must be further assembled to make the Z ring in bacteria. Conventional electron microscopy (EM) has failed to image the Z ring or resolve its substructure. Here we describe a procedure that enabled us to image reconstructed, inside-out FtsZ rings by negative-stain EM, revealing the arrangement of filaments. We took advantage of a unique lipid that spontaneously forms 500 nm diameter tubules in solution. We optimized conditions for Z-ring assembly with fluorescence light microscopy and then prepared specimens for negative-stain EM. Reconstituted FtsZ rings, encircling the tubules, were clearly resolved. The rings appeared as ribbons of filam

SUBMITTER: Milam SL 

PROVIDER: S-EPMC3388225 | biostudies-literature | 2012 Jul

REPOSITORIES: biostudies-literature