Details

Autor(en) / Beteiligte

• Hou, Sen
• Wieczorek, Stefan A.
• Kaminski, Tomasz S.
• Ziebacz, Natalia
• Tabaka, Marcin
• Sorto, Nohemy A.
• Foss, Marie H.
• Shaw, Jared T.
• Thanbichler, Martin
• Weibel, Douglas B.
• Nieznanski, Krzysztof
• Holyst, Robert
• Garstecki, Piotr

Titel

Characterization of Caulobacter crescentus FtsZ Protein Using Dynamic Light Scattering

Ist Teil von

• The Journal of biological chemistry, 2012-07, Vol.287 (28), p.23878-23886

Ort / Verlag

United States: Elsevier Inc

Erscheinungsjahr

2012

Link zum Volltext

Quelle

MEDLINE

Beschreibungen/Notizen

• The self-assembly of the tubulin homologue FtsZ at the mid-cell is a critical step in bacterial cell division. We introduce dynamic light scattering (DLS) spectroscopy as a new method to study the polymerization kinetics of FtsZ in solution. Analysis of the DLS data indicates that the FtsZ polymers are remarkably monodisperse in length, independent of the concentrations of GTP, GDP, and FtsZ monomers. Measurements of the diffusion coefficient of the polymers demonstrate that their length is remarkably stable until the free GTP is consumed. We estimated the mean size of the FtsZ polymers within this interval of stable length to be between 9 and 18 monomers. The rates of FtsZ polymerization and depolymerization are likely influenced by the concentration of GDP, as the repeated addition of GTP to FtsZ increased the rate of polymerization and slowed down depolymerization. Increasing the FtsZ concentration did not change the size of FtsZ polymers; however, it increased the rate of the depolymerization reaction by depleting free GTP. Using transmission electron microscopy we observed that FtsZ forms linear polymers in solutions which rapidly convert to large bundles upon contact with surfaces at time scales as short as several seconds. Finally, the best studied small molecule that binds to FtsZ, PC190723, had no stabilizing effect on Caulobacter crescentus FtsZ filaments in vitro, which complements previous studies with Escherichia coli FtsZ and confirms that this class of small molecules binds Gram-negative FtsZ weakly. Background: Self-assembly of the tubulin-homologue FtsZ is critical in bacterial cell division. Results: Dynamic light scattering (DLS) measurements provide insight into the kinetics and stable length of Caulobacter crescentus FtsZ in vitro. Conclusion:C. crescentus FtsZ forms short linear polymers in solution with the assembly rate depending on the concentrations of GTP and GDP. Significance: DLS is a valuable technique for studying the polymerization of cytoskeletal proteins.