7k45
From Proteopedia
SARS-CoV-2 spike in complex with the S2E12 neutralizing antibody Fab fragment (local refinement of the RBD and Fab variable domains)
Structural highlights
FunctionSPIKE_SARS2 attaches the virion to the cell membrane by interacting with host receptor, initiating the infection (By similarity). Binding to human ACE2 receptor and internalization of the virus into the endosomes of the host cell induces conformational changes in the Spike glycoprotein (PubMed:32142651, PubMed:32075877, PubMed:32155444). Uses also human TMPRSS2 for priming in human lung cells which is an essential step for viral entry (PubMed:32142651). Proteolysis by cathepsin CTSL may unmask the fusion peptide of S2 and activate membranes fusion within endosomes.[HAMAP-Rule:MF_04099][1] [2] [3] mediates fusion of the virion and cellular membranes by acting as a class I viral fusion protein. Under the current model, the protein has at least three 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) 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.[HAMAP-Rule:MF_04099] Acts as a viral fusion peptide which is unmasked following S2 cleavage occurring upon virus endocytosis.[HAMAP-Rule:MF_04099] Publication Abstract from PubMedEfficient therapeutic options are needed to control the spread of SARS-CoV-2 that has caused more than 922,000 fatalities as of September 13(th), 2020. We report the isolation and characterization of two ultrapotent SARS-CoV-2 human neutralizing antibodies (S2E12 and S2M11) that protect hamsters against SARS-CoV-2 challenge. Cryo-electron microscopy structures show that S2E12 and S2M11 competitively block ACE2 attachment and that S2M11 also locks the spike in a closed conformation by recognition of a quaternary epitope spanning two adjacent receptor-binding domains. Cocktails including S2M11, S2E12 or the previously identified S309 antibody broadly neutralize a panel of circulating SARS-CoV-2 isolates and activate effector functions. Our results pave the way to implement antibody cocktails for prophylaxis or therapy, circumventing or limiting the emergence of viral escape mutants. Ultrapotent human antibodies protect against SARS-CoV-2 challenge via multiple mechanisms.,Tortorici MA, Beltramello M, Lempp FA, Pinto D, Dang HV, Rosen LE, McCallum M, Bowen J, Minola A, Jaconi S, Zatta F, De Marco A, Guarino B, Bianchi S, Lauron EJ, Tucker H, Zhou J, Peter A, Havenar-Daughton C, Wojcechowskyj JA, Case JB, Chen RE, Kaiser H, Montiel-Ruiz M, Meury M, Czudnochowski N, Spreafico R, Dillen J, Ng C, Sprugasci N, Culap K, Benigni F, Abdelnabi R, Foo SC, Schmid MA, Cameroni E, Riva A, Gabrieli A, Galli M, Pizzuto MS, Neyts J, Diamond MS, Virgin HW, Snell G, Corti D, Fink K, Veesler D Science. 2020 Sep 24. pii: science.abe3354. doi: 10.1126/science.abe3354. PMID:32972994[4] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
| ||||||||||||||||||||
