Crystallization and preliminary X-ray crystallographic studies of the PYD domain of human NALP3

The NALP3 inflammasome is a macromolecular complex that is responsible for the innate immune response against infection by bacterial and viral pathogens. The NALP3 inflammasome is composed of three protein components: NALP3, ASC and caspase 1. Interaction between NALP3 and ASC via PYD domains is critical for the assembly of the NALP3 inflammasome. In this study, human NALP3 PYD, corresponding to amino acids 3–110, was overexpressed in Escherichia coli using engineered C-terminal His tags. NALP3 PYD was then purified to homogeneity and crystallized at 293 K. Finally, X-ray diffraction data were collected to a resolution of 1.7 Å from a crystal belonging to the primitive monoclinic space group P2₁, with unit-cell parameters a = 42.03, b = 60.14, c = 51.61 Å, β = 107.40°.