5yl9
1.86 Angstrom crystal structure of human Coronavirus 229E fusion core
Structural highlights
FunctionSPIKE_CVH22 S1 region attaches the virion to the cell membrane by interacting with human ANPEP/aminopeptidase N, initiating the infection. Binding to the receptor probably induces conformational changes in the S glycoprotein unmasking the fusion peptide of S2 region and activating membranes fusion. S2 region belongs to the class I viral fusion protein. Under the current model, the protein has at least 3 conformational states: pre-fusion native state, pre-hairpin intermediate state, and post-fusion hairpin state. During viral and target cell membrane fusion, the coiled coil regions (heptad repeats) regions assume a trimer-of-hairpins structure, positioning the fusion peptide in close proximity to the C-terminal region of the ectodomain. The formation of this structure appears to drive apposition and subsequent fusion of viral and target cell membranes (By similarity). Publication Abstract from PubMedHuman coronavirus 229E (HCoV-229E) usually causes mild upper respiratory infections in heathy adults, but may lead to severe complications or mortality in individuals with weakened immune systems. Virus entry of HCoV-229E is mediated by its spike (S) protein, where the S1 domain facilitates attachment to host cells and the S2 domain is involved in subsequent fusion of the virus and host membranes. During the fusion process, two heptad repeats, HR1 and HR2, in the S2 domain assemble into a six-helix membrane-fusion structure termed the fusion core. Here, the complete fusion-core structure of HCoV-229E has been determined at 1.86 A resolution, representing the most complete post-fusion conformation thus far among published human alphacoronavirus (alpha-HCoV) fusion-core structures. The overall structure of the HCoV-229E fusion core is similar to those of SARS, MERS and HCoV-NL63, but the packing of its 3HR1 core differs from those of SARS and MERS in that it contains more noncanonical `x' and `da' layers. Side-by-side electrostatic surface comparisons reveal that the electrostatic surface potentials are opposite in alpha-HCoVs and beta-HCoVs at certain positions and that the HCoV-229E surface also appears to be the most hydrophobic among the various HCoVs. In addition to the highly conserved hydrophobic interactions between HR1 and HR2, some polar and electrostatic interactions are also well preserved across different HCoVs. This study adds to the structural profiling of HCoVs to aid in the structure-based design of pan-coronavirus small molecules or peptides to inhibit viral fusion. Crystal structure of the post-fusion core of the Human coronavirus 229E spike protein at 1.86 A resolution.,Yan L, Meng B, Xiang J, Wilson IA, Yang B Acta Crystallogr D Struct Biol. 2018 Sep 1;74(Pt 9):841-851. doi:, 10.1107/S2059798318008318. Epub 2018 Sep 3. PMID:30198895[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
| ||||||||||||||||||
