6CB7

CRYSTAL STRUCTURE OF VACCINIA VIRUS A6 N-TERMINUS (SPACE GROUP C2)

Summary for 6CB7

• Entry DOI: 10.2210/pdb6cb7/pdb
• Related: 6CB6
• Descriptor: Protein A6, NICKEL (II) ION (3 entities in total)
• Functional Keywords: vaccinia virus, a6, poxviruses, virion core protein, virion morphogenesis, viral protein
• Biological source: Vaccinia virus (strain Copenhagen) (VACV)
• Total number of polymer chains: 1
• Total formula weight: 14108.03

Authors

Han, Y.,Zhang, B.,Deng, J. (deposition date: 2018-02-02, release date: 2018-12-12, Last modification date: 2023-10-04)

Primary citation

Pathak, P.K.,Peng, S.,Meng, X.,Han, Y.,Zhang, B.,Zhang, F.,Xiang, Y.,Deng, J.
Structure of a lipid-bound viral membrane assembly protein reveals a modality for enclosing the lipid bilayer.
Proc. Natl. Acad. Sci. U.S.A., 115:7028-7032, 2018

PubMed Abstract: Cellular membranes are maintained as closed compartments, broken up only transiently during membrane reorganization or lipid transportation. However, open-ended membranes, likely derived from scissions of the endoplasmic reticulum, persist in vaccinia virus-infected cells during the assembly of the viral envelope. A group of viral membrane assembly proteins (VMAPs) were identified as essential for this process. To understand the mechanism of VMAPs, we determined the 2.2-Å crystal structure of the largest member, named A6, which is a soluble protein with two distinct domains. The structure of A6 displays a novel protein fold composed mainly of alpha helices. The larger C-terminal domain forms a unique cage that encloses multiple glycerophospholipids with a lipid bilayer-like configuration. The smaller N-terminal domain does not bind lipid but negatively affects lipid binding by A6. Mutations of key hydrophobic residues lining the lipid-binding cage disrupt lipid binding and abolish viral replication. Our results reveal a protein modality for enclosing the lipid bilayer and provide molecular insight into a viral machinery involved in generating and/or stabilizing open-ended membranes.

PubMed: 29915071
DOI: 10.1073/pnas.1805855115

Experimental method

X-RAY DIFFRACTION (1.6 Å)