5CLR

Crystal structure of LegK4_APO Kinase

Summary for 5CLR

• Entry DOI: 10.2210/pdb5clr/pdb
• Related: 5CKW
• Descriptor: LegK4 (1 entity in total)
• Functional Keywords: legionella, bacterial effectors, serine/threonine kinase, type iv secretion system, transferase
• Biological source: Legionella pneumophila (strain Lens)
• Total number of polymer chains: 2
• Total formula weight: 103157.80

Authors

Flayhan, A.,Terradot, L. (deposition date: 2015-07-16, release date: 2015-10-14, Last modification date: 2024-11-13)

Primary citation

Flayhan, A.,Berge, C.,Bailo, N.,Doublet, P.,Bayliss, R.,Terradot, L.
The structure of Legionella pneumophila LegK4 type four secretion system (T4SS) effector reveals a novel dimeric eukaryotic-like kinase.
Sci Rep, 5:14602-14602, 2015

PubMed Abstract: Bacterial pathogens subvert signalling pathways to promote invasion and/or replication into the host. LegK1-4 proteins are eukaryotic-like serine/threonine kinases that are translocated by the Dot/Icm type IV secretion system (T4SS) of several Legionella pneumophila strains. We present the crystal structures of an active fragment of the LegK4 protein in apo and substrate-bound states. The structure of LegK4(1-445) reveals a eukaryotic-like kinase domain flanked by a novel cap domain and a four-helix bundle. The protein self-assembles through interactions mediated by helices αF and αG that generate a dimeric interface not previously observed in a protein kinase. The helix αG is displaced compared to previous kinase structures, and its role in stabilization of the activation loop is taken on by the dimerisation interface. The apo-form of the protein has an open conformation with a disordered P-loop but a structured activation segment in absence of targeted phosphorylation. The nucleotide-binding site of LegK4 contains an unusual set of residues that mediate non-canonical interactions with AMP-PNP. Nucleotide binding results in limited changes in the active site, suggesting that LegK4 constitutive kinase activity does not depend on phosphorylation of the activation loop but on the stabilizing effects of the dimer.

PubMed: 26419332
DOI: 10.1038/srep14602

Experimental method

X-RAY DIFFRACTION (3.706 Å)