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Updated: Jul 16, 2026

Production, Crystallization, and Structure Determination of the IKK-binding Domain of NEMO
Published on: December 28, 2019
X-ray crystallographic structure of the Norwalk virus capsid
B V Prasad1, M E Hardy, T Dokland
1Verna and Marrs Mclean Department of Biochemistry, Division of Molecular Virology, Baylor College of Medicine, Houston, TX 77030, USA. bprasad@bcm.tmc.edu
Abstract:
Norwalk virus, a noncultivatable human calicivirus, is the major cause of epidemic gastroenteritis in humans. The first x-ray structure of a calicivirus capsid, which consists of 180 copies of a single protein, has been determined by phase extension from a low-resolution electron microscopy structure. The capsid protein has a protruding (P) domain connected by a flexible hinge to a shell (S) domain that has a classical eight-stranded beta-sandwich motif. The structure of the P domain is unlike that of any other viral protein with a subdomain exhibiting a fold similar to that of the second domain in the eukaryotic translation elongation factor-Tu. This subdomain, located at the exterior of the capsid, has the largest sequence variation among Norwalk-like human caliciviruses and is likely to contain the determinants of strain specificity and cell binding.
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