title: Structural and enzymatic characterization of a host-specificity determinant from Salmonella.
abstract: GtgE is an effector protein from Salmonella Typhimurium that modulates trafficking of the Salmonella-containing vacuole. It exerts its function by cleaving the Rab-family GTPases Rab29, Rab32 and Rab38, thereby preventing the delivery of antimicrobial factors to the bacteria-containing vacuole. Here, the crystal structure of GtgE at 1.65 Å resolution is presented, and structure-based mutagenesis and in vivo infection assays are used to identify its catalytic triad. A panel of cysteine protease inhibitors were examined and it was determined that N-ethylmaleimide, antipain and chymostatin inhibit GtgE activity in vitro. These findings provide the basis for the development of novel therapeutic strategies to combat Salmonella infections.
authors: Laboratory of Structural Microbiology, Rockefeller University, New York, NY 10065, USA.
authors: Amanda C
authors: AC
authors: Kohler
authors: Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT 06536, USA.
authors: Stefania
authors: S
authors: Spanò
authors: Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT 06536, USA.
authors: Jorge E
authors: JE
authors: Galán
authors: Laboratory of Structural Microbiology, Rockefeller University, New York, NY 10065, USA.
authors: C Erec
authors: CE
authors: Stebbins
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001426:Bacterial Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D019556:COS Cells; D020134:Catalytic Domain; D002522:Chlorocebus aethiops; D018360:Crystallography, X-Ray; D015853:Cysteine Proteinase Inhibitors / Q000737:chemistry; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D058507:Host Specificity; D054884:Host-Pathogen Interactions; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D021381:Protein Transport; D059748:Proteolysis; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012486:Salmonella typhimurium / Q000737:chemistry* / Q000201:enzymology; D013329:Structure-Activity Relationship; D014617:Vacuoles / Q000378:metabolism; D020691:rab GTP-Binding Proteins / Q000737:chemistry* / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D015853:Cysteine Proteinase Inhibitors; D011994:Recombinant Proteins; C412058:RAB38 protein, human; D020691:rab GTP-Binding Proteins
keywords: GtgE; Rab GTPase; Salmonella Typhi; Salmonella Typhimurium; cysteine proteases