Crystal structure of a Legionella pneumophila ecto -triphosphate diphosphohydrolase, a structural and functional homolog of the eukaryotic NTPDases.
Many pathogenic bacteria have sophisticated mechanisms to interfere with the mammalian immune response. These include the disruption of host extracellular ATP levels that, in humans, is tightly regulated by the nucleoside triphosphate diphosphohydrolase family (NTPDases). NTPDases are found almost exclusively in eukaryotes, the notable exception being their presence in some pathogenic prokaryotes. To address the function of bacterial NTPDases, we describe the structures of an NTPDase from the pathogen Legionella pneumophila (Lpg1905/Lp1NTPDase) in its apo state and in complex with the ATP analog AMPPNP and the subtype-specific NTPDase inhibitor ARL 67156. Lp1NTPDase is structurally and catalytically related to eukaryotic NTPDases and the structure provides a basis for NTPDase-specific inhibition. Furthermore, we demonstrate that the activity of Lp1NTPDase correlates directly with intracellular replication of Legionella within macrophages. Collectively, these findings provide insight into the mechanism of this enzyme and highlight its role in host-pathogen interactions.
The Protein Crystallography Unit, ARC Centre of Excellence in Structural and Functional Microbial Genomics, Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, Victoria 3800, Australia.
Julian P
JP
Vivian
Patrice
P
Riedmaier
Honghua
H
Ge
Jérôme
J
Le Nours
Fiona M
FM
Sansom
Matthew C J
MC
Wilce
Emma
E
Byres
Manisha
M
Dias
Jason W
JW
Schmidberger
Peter J
PJ
Cowan
Anthony J F
AJ
d'Apice
Elizabeth L
EL
Hartland
Jamie
J
Rossjohn
Travis
T
Beddoe
D000255:Adenosine Triphosphate / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism; D000266:Adenylyl Imidodiphosphate / Q000737:chemistry / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D001665:Binding Sites; D018360:Crystallography, X-Ray; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000378:metabolism; D056890:Eukaryota / Q000201:enzymology*; D006801:Humans; D016952:Legionella pneumophila / Q000201:enzymology*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D017434:Protein Structure, Tertiary; D011755:Pyrophosphatases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D051381:Rats; D016415:Sequence Alignment
C092431:6-N,N-diethyl-beta,gamma-dibromomethylene-D-ATP; D001426:Bacterial Proteins; D004791:Enzyme Inhibitors; D000266:Adenylyl Imidodiphosphate; D000255:Adenosine Triphosphate; D011755:Pyrophosphatases; C021895:nucleoside triphosphate pyrophosphatase