1HE1

Crystal structure of the complex between the GAP domain of the Pseudomonas aeruginosa ExoS toxin and human Rac

Summary for 1HE1

• Entry DOI: 10.2210/pdb1he1/pdb
• Related: 1E96 1HE9 1MH1
• NMR Information: BMRB: 5511
• Descriptor: EXOENZYME S, RAS-RELATED C3 BOTULINUM TOXIN SUBSTRATE 1, NICKEL (II) ION, ... (7 entities in total)
• Functional Keywords: signaling protein, signalling complex, exos, rac, pseudomonas aeruginosa, gap, toxin, virulence factor, transition state, protein-protein complex, gtpase, signal transduction
• Biological source: PSEUDOMONAS AERUGINOSA; More
• Cellular location: Cell membrane; Lipid-anchor; Cytoplasmic side (By similarity): P15154
• Total number of polymer chains: 4
• Total formula weight: 68987.09

Authors

Wurtele, M.,Wolf, E.,Pederson, K.J.,Buchwald, G.,Ahmadian, M.R.,Barbieri, J.T.,Wittinghofer, A. (deposition date: 2000-11-18, release date: 2001-01-02, Last modification date: 2023-12-13)

Primary citation

Wurtele, M.,Wolf, E.,Pederson, K.J.,Buchwald, G.,Ahmadian, M.R.,Barbieri, J.T.,Wittinghofer, A.
How the Pseudomonas Aeruginosa Exos Toxin Downregulates Rac
Nat.Struct.Biol., 8:23-, 2001

PubMed Abstract: Pseudomonas aeruginosa is an opportunistic bacterial pathogen. One of its major toxins, ExoS, is translocated into eukaryotic cells by a type III secretion pathway. ExoS is a dual function enzyme that affects two different Ras-related GTP binding proteins. The C-terminus inactivates Ras through ADP ribosylation, while the N-terminus inactivates Rho proteins through its GTPase activating protein (GAP) activity. Here we have determined the three-dimensional structure of a complex between Rac and the GAP domain of ExoS in the presence of GDP and AlF3. Composed of approximately 130 residues, this ExoS domain is the smallest GAP hitherto described. The GAP domain of ExoS is an all-helical protein with no obvious structural homology, and thus no recognizable evolutionary relationship, with the eukaryotic RhoGAP or RasGAP fold. Similar to other GAPs, ExoS downregulates Rac using an arginine finger to stabilize the transition state of the GTPase reaction, but the details of the ExoS-Rac interaction are unique. Considering the intrinsic resistance of P. aeruginosa to antibiotics, this might open up a new avenue towards blocking its pathogenicity.

PubMed: 11135665
DOI: 10.1038/83007

Experimental method

X-RAY DIFFRACTION (2 Å)