6SI9

FtsZ-refold

Summary for 6SI9

• Entry DOI: 10.2210/pdb6si9/pdb
• Descriptor: Cell division protein FtsZ, GUANOSINE-5'-DIPHOSPHATE, 1,2-ETHANEDIOL, ... (5 entities in total)
• Functional Keywords: cell division protein, cell cycle
• Biological source: Staphylococcus aureus
• Total number of polymer chains: 1
• Total formula weight: 32398.37

Authors

Fernandez-Tornero, C.,Andreu, J.M.,Ruiz, F.M. (deposition date: 2019-08-09, release date: 2020-02-19, Last modification date: 2024-01-24)

Primary citation

Huecas, S.,Canosa-Valls, A.J.,Araujo-Bazan, L.,Ruiz, F.M.,Laurents, D.V.,Fernandez-Tornero, C.,Andreu, J.M.
Nucleotide-induced folding of cell division protein FtsZ from Staphylococcus aureus.
Febs J., 287:4048-4067, 2020

PubMed Abstract: The essential bacterial division protein FtsZ uses GTP binding and hydrolysis to assemble into dynamic filaments that treadmill around the Z-ring, guiding septal wall synthesis and cell division. FtsZ is a structural homolog of tubulin and a target for discovering new antibiotics. Here, using FtsZ from the pathogen S. aureus (SaFtsZ), we reveal that, prior to assembly, FtsZ monomers require nucleotide binding for folding; this is possibly relevant to other mesophilic FtsZs. Apo-SaFtsZ is essentially unfolded, as assessed by nuclear magnetic resonance and circular dichroism. Binding of GTP (≥ 1 mm) dramatically shifts the equilibrium toward the active folded protein. Supportingly, SaFtsZ refolded with GDP crystallizes in a native structure. Apo-SaFtsZ also folds with 3.4 m glycerol, enabling high-affinity GTP binding (K 20 nm determined by isothermal titration calorimetry) similar to thermophilic stable FtsZ. Other stabilizing agents that enhance nucleotide binding include ethylene glycol, trimethylamine N-oxide, and several bacterial osmolytes. High salt stabilizes SaFtsZ without bound nucleotide in an inactive twisted conformation. We identified a cavity behind the SaFtsZ-GDP nucleotide-binding pocket that harbors different small compounds, which is available for extended nucleotide-replacing inhibitors. Furthermore, we devised a competition assay to detect any inhibitors that overlap the nucleotide site of SaFtsZ, or Escherichia coli FtsZ, employing osmolyte-stabilized apo-FtsZs and the specific fluorescence anisotropy change in mant-GTP upon dissociation from the protein. This robust assay provides a basis to screening for high-affinity GTP-replacing ligands, which combined with structural studies and phenotypic profiling should facilitate development of a next generation of FtsZ-targeting antibacterial inhibitors.

PubMed: 31997533
DOI: 10.1111/febs.15235

Experimental method

X-RAY DIFFRACTION (1.9 Å)