Structural basis for Rab1 de-AMPylation by the Legionella pneumophila effector SidD

DOI: 10.1371/journal.ppat.1003382
PMID: 23696742

Authors: Yang Chen (National Institutes of Health) , Igor Tascón (CIC bioGUNE) , M. Ramona Neunuebel (National Institutes of Health) , Chiara Pallara (Barcelona Supercomputing Center) , Jacqueline Brady (National Institutes of Health) , Lisa N. Kinch (University of Texas Southwestern Medical Center) , Juan Fernández-Recio (Barcelona Supercomputing Center) , Adriana Rojas (CIC bioGUNE) , Matthias P. Machner (National Institutes of Health) , Aitor Hierro (CIC bioGUNE)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Plos Pathogens , VOL 9 (5)

State: Published (Approved)
Published: May 2013
Diamond Proposal Number(s): 8302 , 7512

Abstract: The covalent attachment of adenosine monophosphate (AMP) to proteins, a process called AMPylation (adenylylation), has recently emerged as a novel theme in microbial pathogenesis. Although several AMPylating enzymes have been characterized, the only known virulence protein with de-AMPylation activity is SidD from the human pathogen Legionella pneumophila. SidD de-AMPylates mammalian Rab1, a small GTPase involved in secretory vesicle transport, thereby targeting the host protein for inactivation. The molecular mechanisms underlying Rab1 recognition and de-AMPylation by SidD are unclear. Here, we report the crystal structure of the catalytic region of SidD at 1.6 Å resolution. The structure reveals a phosphatase-like fold with additional structural elements not present in generic PP2C-type phosphatases. The catalytic pocket contains a binuclear metal-binding site characteristic of hydrolytic metalloenzymes, with strong dependency on magnesium ions. Subsequent docking and molecular dynamics simulations between SidD and Rab1 revealed the interface contacts and the energetic contribution of key residues to the interaction. In conjunction with an extensive structure-based mutational analysis, we provide in vivo and in vitro evidence for a remarkable adaptation of SidD to its host cell target Rab1 which explains how this effector confers specificity to the reaction it catalyses.

Journal Keywords: Bacterial; Crystallography; X-Ray; Humans; Legionella; PhosphoProtein; Quaternary; Structure-Activity; rab1 GTP-Binding Proteins

Diamond Keywords: Legionnaires' Disease; Bacteria

Subject Areas: Biology and Bio-materials


Instruments: I24-Microfocus Macromolecular Crystallography

Other Facilities: ESRF; PROXIMA1 at SOLEIL

Added On: 20/03/2014 11:48

Documents:
file-3.pdf

Discipline Tags:

Pathogens Infectious Diseases Health & Wellbeing Structural biology Life Sciences & Biotech

Technical Tags:

Diffraction Macromolecular Crystallography (MX)