PDBsum entry 4g6t

Chaperone

PDB id: 4g6t

Contents

Protein chains

128 a.a.

71 a.a.

Waters ×116

PDB id:

4g6t

Name:

Chaperone

Title:

Structure of the hopa1-scha chaperone-effector complex

Structure:

Type iii chaperone protein shca. Chain: a. Engineered: yes. Type iii effector hopa1. Chain: b. Engineered: yes

Source:

Pseudomonas syringae pv. Tomato. Organism_taxid: 223283. Strain: dc3000. Gene: shca, pspto_5353. Gene: hopa1, pspto_5354

Resolution:

1.56Å R-factor: 0.211 R-free: 0.230

Authors:

C.E.Stebbins,R.Janjusevic,C.M.Quezada

Key ref:

R.Janjusevic et al. (2013). Structure of the HopA1(21-102)-ShcA chaperone-effector complex of Pseudomonas syringae reveals conservation of a virulence factor binding motif from animal to plant pathogens. J Bacteriol, 195, 658-664. PubMed id: 23204470

Date:

19-Jul-12 Release date: 05-Jun-13

Protein chain

Q87UE6  (Q87UE6_PSESM) -  Type III chaperone protein ShcA from Pseudomonas syringae pv. tomato (strain ATCC BAA-871 / DC3000)

Seq: 127 a.a.

Struc: 128 a.a.

Protein chain

Q87UE5  (Q87UE5_PSESM) -  Type III effector HopA1 from Pseudomonas syringae pv. tomato (strain ATCC BAA-871 / DC3000)

Seq: 380 a.a.

Struc: 71 a.a.

Enzyme reactions

• Enzyme class: Chains A, B: E.C.?

J Bacteriol 195:658-664 (2013)

PubMed id: 23204470

Structure of the HopA1(21-102)-ShcA chaperone-effector complex of Pseudomonas syringae reveals conservation of a virulence factor binding motif from animal to plant pathogens.

R.Janjusevic, C.M.Quezada, J.Small, C.E.Stebbins.

ABSTRACT

Pseudomonas syringae injects numerous bacterial proteins into host plant cells through a type 3 secretion system (T3SS). One of the first such bacterial effectors discovered, HopA1, is a protein that has unknown functions in the host cell but possesses close homologs that trigger the plant hypersensitive response in resistant strains. Like the virulence factors in many bacterial pathogens of animals, HopA1 depends upon a cognate chaperone in order to be effectively translocated by the P. syringae T3SS. Herein, we report the crystal structure of a complex of HopA1(21-102) with its chaperone, ShcA, determined to 1.56-Å resolution. The structure reveals that three key features of the chaperone-effector interactions found in animal pathogens are preserved in the Gram-negative pathogens of plants, namely, (i) the interaction of the chaperone with a nonglobular polypeptide of the effector, (ii) an interaction centered on the so-called β-motif, and (iii) the presence of a conserved hydrophobic patch in the chaperone that recognizes the β-motif. Structure-based mutagenesis and biochemical studies have established that the β-motif is critical for the stability of this complex. Overall, these results show that the β-motif interactions are broadly conserved in bacterial pathogens utilizing T3SSs, spanning an interkingdom host range.