HIV-2 CA T=1 Icosahedron; assembled via lipid templating

MYO-INOSITOL HEXAKISPHOSPHATE; INOSITOL 1,2,3,4,5,6-HEXAKISPHOSPHATE

Structural insights into HIV-2 CA lattice formation and FG-pocket binding revealed by single-particle cryo-EM.

An HIV-1 CA chain from pentamers (PDB: 8CKW) was initially fit into the density by rigid body fitting. It was then mutated to match the HIV-2 sequence, with unmodeled residues being replaced before flexible fitting and refinement into the map volume.

Due to structural similarities expected between HIV-2 and HIV-1, an HIV-1 model was used for initial fitting.

The mixed buffer of storage buffer for the protein and lipid components with IP6 supplemented.

C-terminally hexahistidine tagged HIV-2 CA associated with a micelle decorated with NiNTA headgroups which results in the assembly of an icosahedral lattice of CA.
HIV-2 capsid protein assembled into a lattice via lipid templating.

Collected at Brookhaven National Laboratory

Sample was prepared with 400 uM HIV-2 CA-6xHis protein, 5.9 mM lipid mix (described in publication), and 4 mM IP6.

Sample was well-distributed on the grid, mostly monodisperse. Perhaps slightly more particles on carbon versus in the hole.

Grids were dual-side blotted with blot force 0 for 5.5 sec before plunge freezing in liquid ethane.

Full length HIV-2 GL-AN capsid protein with a C-terminal Gly-Ser-Ser linker to a hexahistidine tag following proteolytic processing of N-terminal Met.

PVQQTGGGNYIHVPLSPRTLNAWVKLVEDKKFGAEVVPGFQALSEGCTPYDINQMLNCVGDHQAAMQIIREIINDEAADW
DAQHPIPGPLPAGQLRDPRGSDIAGTTSTVEEQIQWMYRPQNPVPVGNIYRRWIQIGLQKCVRMYNPTNILDVKQGPKEP
FQSYVDRFYKSLRAEQTDPAVKNWMTQTLLIQNANPDCKLVLKGLGMNPTLEEMLTACQGVGGPGQKARLMGSSHHHHHH

National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID)

icosahedral asymmetric unit, std point frame

Assembly of HIV-2 CA, templated on functionalized micelles, consisting of a T=1 icosahedral array of 12 pentamers.

PVQQTGGGNYIHVPLSPRTLNAWVKLVEDKKFGAEVVPGFQALSEGCTPYDINQMLNCVGDHQAAMQIIREIINDEAADW
DAQHPIPGPLPAGQLRDPRGSDIAGTTSTVEEQIQWMYRPQNPVPVGNIYRRWIQIGLQKCVRMYNPTNILDVKQGPKEP
FQSYVDRFYKSLRAEQTDPAVKNWMTQTLLIQNANPDCKLVLKGLGMNPTLEEMLTACQGVGGPGQKARLM