8DUF

Crystal structure of Venezuelan Equine Encephalitis alphavirus (VEEV) nonstructural protein 2 (nsp2) (K741A/K767A) protease domain

Summary for 8DUF

• Entry DOI: 10.2210/pdb8duf/pdb
• Descriptor: nsp2 protease domain (2 entities in total)
• Functional Keywords: nonstructural protein, protease, viral protein
• Biological source: Venezuelan equine encephalitis virus
• Total number of polymer chains: 1
• Total formula weight: 36546.68

Authors

Lountos, G.T. (deposition date: 2022-07-27, release date: 2023-03-15, Last modification date: 2023-10-25)

Primary citation

Hoffka, G.,Lountos, G.T.,Needle, D.,Wlodawer, A.,Waugh, D.S.,Tozser, J.,Motyan, J.A.
Self-inhibited State of Venezuelan Equine Encephalitis Virus (VEEV) nsP2 Cysteine Protease: A Crystallographic and Molecular Dynamics Analysis.
J.Mol.Biol., 435:168012-168012, 2023

PubMed Abstract: The Venezuelan equine encephalitis virus (VEEV) belongs to the Togaviridae family and is pathogenic to both humans and equines. The VEEV non-structural protein 2 (nsP2) is a cysteine protease (nsP2pro) that processes the polyprotein and thus it is a drug target for inhibitor discovery. The atomic structure of the VEEV nsP2 catalytic domain was previously characterized by both X-ray crystallography and computational studies. A modified nsP2pro harboring a N475A mutation in the N terminus was observed to exhibit an unexpected conformation: the N-terminal residues bind to the active site, mimicking binding of a substrate. The large conformational change of the N terminus was assumed to be induced by the N475A mutation, as N475 has an important role in stabilization of the N terminus and the active site. This conformation was first observed in the N475A mutant, but we also found it while determining a crystal structure of the catalytically active nsP2pro containing the wild-type N475 active site residue and K741A/K767A surface entropy reduction mutations. This suggests that the N475A mutation is not a prerequisite for self-inhibition. Here, we describe a high resolution (1.46 Å) crystal structure of a truncated nsP2pro (residues 463-785, K741A/K767A) and analyze the structure further by molecular dynamics to study the active and self-inhibited conformations of nsP2pro and its N475A mutant. A comparison of the different conformations of the N-terminal residues sheds a light on the interactions that play an important role in the stabilization of the enzyme.

PubMed: 36792007
DOI: 10.1016/j.jmb.2023.168012

Experimental method

X-RAY DIFFRACTION (1.46 Å)