5DKO

The structure of Escherichia coli ZapD

Summary for 5DKO

• Entry DOI: 10.2210/pdb5dko/pdb
• Descriptor: Cell division protein ZapD, SULFATE ION (3 entities in total)
• Functional Keywords: cell division, ftsz ring, replication
• Biological source: Escherichia coli
• Total number of polymer chains: 1
• Total formula weight: 30289.60

Authors

Wroblewski, C.,Kimber, M.S. (deposition date: 2015-09-03, release date: 2016-04-13, Last modification date: 2023-09-27)

Primary citation

Roach, E.J.,Wroblewski, C.,Seidel, L.,Berezuk, A.M.,Brewer, D.,Kimber, M.S.,Khursigara, C.M.
Structure and Mutational Analyses of Escherichia coli ZapD Reveal Charged Residues Involved in FtsZ Filament Bundling.
J.Bacteriol., 198:1683-1693, 2016

PubMed Abstract: Bacterial cell division is an essential and highly coordinated process. It requires the polymerization of the tubulin homologue FtsZ to form a dynamic ring (Z-ring) at midcell. Z-ring formation relies on a group of FtsZ-associated proteins (Zap) for stability throughout the process of division. In Escherichia coli, there are currently five Zap proteins (ZapA through ZapE), of which four (ZapA, ZapB, ZapC, and ZapD) are small soluble proteins that act to bind and bundle FtsZ filaments. In particular, ZapD forms a functional dimer and interacts with the C-terminal tail of FtsZ, but little is known about its structure and mechanism of action. Here, we present the crystal structure of Escherichia coli ZapD and show it forms a symmetrical dimer with centrally located α-helices flanked by β-sheet domains. Based on the structure of ZapD and its chemical cross-linking to FtsZ, we targeted nine charged ZapD residues for modification by site-directed mutagenesis. Using in vitro FtsZ sedimentation assays, we show that residues R56, R221, and R225 are important for bundling FtsZ filaments, while transmission electron microscopy revealed that altering these residues results in different FtsZ bundle morphology compared to those of filaments bundled with wild-type ZapD. ZapD residue R116 also showed altered FtsZ bundle morphology but levels of FtsZ bundling similar to that of wild-type ZapD. Together, these results reveal that ZapD residues R116, R221, and R225 likely participate in forming a positively charged binding pocket that is critical for bundling FtsZ filaments.

PubMed: 27021560
DOI: 10.1128/JB.00969-15

Experimental method

X-RAY DIFFRACTION (2.4 Å)