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FtsZ Polymerization Assays: Simple Protocols and Considerations
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FtsZ Polymerization Assays: Simple Protocols and Considerations

Published on: November 16, 2013

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The Cell Division Protein FtsZ from Streptococcus pneumoniae Exhibits a GTPase Activity Delay

Estefanía Salvarelli1, Marcin Krupka2, Germán Rivas3

  • 1From the Servicio de Microbiología, Hospital Universitario La Paz, IdiPAZ, 28046 Madrid, Spain, Biomol-Informatics S.L., Universidad Autónoma, 28049 Madrid, Spain, esalvarelli@gmail.com.

The Journal of Biological Chemistry
|September 3, 2015
PubMed

Insights

Streptococcus pneumoniae FtsZ (SpnFtsZ) protein assembly is cooperative and requires GTP. SpnFtsZ exhibits unique GTPase activity and forms double-stranded filaments, supporting models of FtsZ polymer cooperativity.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Biochemistry

Background:

  • The cell division protein FtsZ is crucial for bacterial cytokinesis.
  • FtsZ assembly in vitro is a cooperative process dependent on GTP, monovalent cations, and Mg(2+).

Purpose of the Study:

  • To analyze the GTPase activity and assembly dynamics of Streptococcus pneumoniae FtsZ (SpnFtsZ).

Main Methods:

  • In vitro assembly assays.
  • GTPase activity measurements.
  • Sedimentation analysis.
  • Electron microscopy.

Main Results:

  • SpnFtsZ assembled cooperatively with a higher critical concentration than other FtsZ proteins.
  • SpnFtsZ formed high molecular mass, well-defined polymers and double-stranded filaments.
  • GTPase activity was dependent on K(+) and Mg(2+), inhibited by Na(+), and showed a lag phase before reaching the GTPase rate.
  • The lag phase in GTP hydrolysis, absent in initial polymer assembly, suggests a transition to a GTP-hydrolyzing polymer state.

Conclusions:

  • SpnFtsZ assembly and GTPase activity exhibit unique characteristics, including a distinct lag phase.
  • These findings support models explaining FtsZ polymer cooperativity and provide insights into bacterial cell division mechanisms.
Keywords:
GTPaseStreptococcusbacterial divisionprotein assemblyprotein chemistryprotein dynamic

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