Probing the domain structure of FtsZ by random truncation and insertion of GFP.

Journal Article

Random transposon-mediated mutagenesis has been used to create truncations and insertions of green fluorescent protein (GFP), and Venus-yellow fluorescent protein (YFP), in Escherichia coli FtsZ. Sixteen unique insertions were obtained, and one of them, in the poorly conserved C-terminal spacer, was functional for cell division with the Venus-YFP insert. The insertion of enhanced GFP (eGFP) at this same site was not functional; Venus-YFP was found to be superior to eGFP in other respects too. Testing the constructs for dominant negative effects led to the following general conclusion. The N-terminal domain, aa 1-195, is an independently folding domain that can poison Z-ring function when expressed without a functional C-terminal domain. The effects were weak, requiring expression of the mutant at 3-5 times the level of wild-type FtsZ. The C-terminal domain, aa 195-383, was also independently folding, but had no activity in vivo. The differential activity of the N- and C-terminal domains suggests that FtsZ protofilament assembly is directional, with subunits adding primarily at the bottom of the protofilament. Directional assembly could occur by either a treadmilling or a dynamic instability mechanism.

Full Text

Duke Authors

Cited Authors

  • Osawa, M; Erickson, HP

Published Date

  • December 2005

Published In

Volume / Issue

  • 151 / Pt 12

Start / End Page

  • 4033 - 4043

PubMed ID

  • 16339948

International Standard Serial Number (ISSN)

  • 1350-0872

Digital Object Identifier (DOI)

  • 10.1099/mic.0.28219-0

Language

  • eng

Conference Location

  • England