5CW7

Crystal structure of the PaaA2-ParE2 antitoxin-toxin complex

Summary for 5CW7

• Entry DOI: 10.2210/pdb5cw7/pdb
• Descriptor: PAAA2, Plasmid stabilization protein ParE, GLYCEROL, ... (4 entities in total)
• Functional Keywords: toxin-antitoxin, toxin
• Biological source: Escherichia coli O157; More
• Total number of polymer chains: 16
• Total formula weight: 164355.18

Authors

Sterckx, Y.G.-J.,Loris, R. (deposition date: 2015-07-27, release date: 2016-06-01, Last modification date: 2024-11-06)

Primary citation

Sterckx, Y.G.,Jove, T.,Shkumatov, A.V.,Garcia-Pino, A.,Geerts, L.,De Kerpel, M.,Lah, J.,De Greve, H.,Van Melderen, L.,Loris, R.
A unique hetero-hexadecameric architecture displayed by the Escherichia coli O157 PaaA2-ParE2 antitoxin-toxin complex.
J.Mol.Biol., 428:1589-1603, 2016

PubMed Abstract: Many bacterial pathogens modulate their metabolic activity, virulence and pathogenicity through so-called "toxin-antitoxin" (TA) modules. The genome of the human pathogen Escherichia coli O157 contains two three-component TA modules related to the known parDE module. Here, we show that the toxin EcParE2 maps in a branch of the RelE/ParE toxin superfamily that is distinct from the branches that contain verified gyrase and ribosome inhibitors. The structure of EcParE2 closely resembles that of Caulobacter crescentus ParE but shows a distinct pattern of conserved surface residues, in agreement with its apparent inability to interact with GyrA. The antitoxin EcPaaA2 is characterized by two α-helices (H1 and H2) that serve as molecular recognition elements to wrap itself around EcParE2. Both EcPaaA2 H1 and H2 are required to sustain a high-affinity interaction with EcParE2 and for the inhibition of EcParE2-mediated killing in vivo. Furthermore, evidence demonstrates that EcPaaA2 H2, but not H1, determines specificity for EcParE2. The initially formed EcPaaA2-EcParE2 heterodimer then assembles into a hetero-hexadecamer, which is stable in solution and is formed in a highly cooperative manner. Together these findings provide novel data on quaternary structure, TA interactions and activity of a hitherto poorly characterized family of TA modules.

PubMed: 26996937
DOI: 10.1016/j.jmb.2016.03.007

Experimental method

X-RAY DIFFRACTION (2.827 Å)