Beak and feather disease virus capsid

The shell of a virus that kills parrots, including the endangered orange-bellied parrot.

Left: the 60-subunit shell (5J36), built from twelve rings of five subunits, one colour per ring. Right, to the same scale: the 10-subunit assembly (5J09), two of those rings face to face.

Beak and feather disease virus (BFDV) infects parrots and cockatoos worldwide, and threatens endangered species such as Australia’s orange-bellied parrot. With Jade Forwood’s group at Charles Sturt University we solved structures of its capsid protein: the expected 60-subunit shell (5J36), the same shell with single-stranded DNA bound (5J37), and a surprising 10-subunit assembly (5J09) that seems to be a genuine step in the virus’s life cycle rather than an oddity of crystallisation.

These were not easy crystals. The huge unit cells pack thousands of reflections onto every diffraction image, so data collection on the Australian Synchrotron’s microfocus beamline needed a small beam, apertures and fine slicing to keep the spots apart. The structures give a starting point for designing a vaccine. My picture of the capsid made it into Cosmos magazine (paper).

PDB entry: 5J36 at PDBe (also at RCSB PDB)
Released: 2016-05-04
Resolution: 2.55 Å
Paper: Structural insights into the assembly and regulation of distinct viral capsid complexes. (Nat Commun, 2016)
More: Technical details, links and electron density

Pictures and video rendered with UCSF ChimeraX; the 3D view is PDBe Mol*.