Structure of the ExoS GTPase activating domain.
Pseudomonas aeruginosa is an opportunistic bacterial pathogen of great medical relevance. One of its major toxins, exoenzyme S (ExoS), is a dual function protein with a C-terminal Ras-ADP-ribosylation domain and an N-terminal GTPase activating protein (GAP) domain specific for Rho-family proteins. We report here the three-dimensional structure of the N-terminal domain of ExoS determined by X-ray crystallography to 2.4 A resolution. Its fold is all helical with a four helix bundle core capped by additional irregular helices. Loops that are known to interact with Rho-family proteins show very large mobility. Considering the importance of ExoS in Pseudomonas pathogenicity, this structure could be of interest for drug targeting.
Max-Planck-Institut für molekulare Physiologie, Abteilung Strukturelle Biologie, Otto-Hahn-Str. 11, 44227 Dortmund, Germany.
M
M
Würtele
L
L
Renault
J T
JT
Barbieri
A
A
Wittinghofer
E
E
Wolf
D036002:ADP Ribose Transferases / Q000737:chemistry*; D001426:Bacterial Proteins / Q000737:chemistry*; D001427:Bacterial Toxins; D018360:Crystallography, X-Ray; D020690:GTPase-Activating Proteins / Q000737:chemistry*; D017434:Protein Structure, Tertiary; D011550:Pseudomonas aeruginosa / Q000737:chemistry / Q000201:enzymology*
D001426:Bacterial Proteins; D001427:Bacterial Toxins; D020690:GTPase-Activating Proteins; D036002:ADP Ribose Transferases; C444820:exoenzyme S