7u0x
From Proteopedia
SARS-Cov2 S protein structure in complex with neutralizing monoclonal antibody 002-13
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 PubMedUnderstanding the molecular features of neutralizing epitopes is important for developing vaccines/therapeutics against emerging SARS-CoV-2 variants. We describe three monoclonal antibodies (mAbs) generated from COVID-19 recovered individuals during the first wave of the pandemic in India. These mAbs had publicly shared near germline gene usage and potently neutralized Alpha and Delta, poorly neutralized Beta, and failed to neutralize Omicron BA.1 SARS-CoV-2 variants. Structural analysis of these mAbs in complex with trimeric spike protein showed that all three mAbs bivalently bind spike with two mAbs targeting class 1 and one targeting a class 4 receptor binding domain epitope. The immunogenetic makeup, structure, and function of these mAbs revealed specific molecular interactions associated with the potent multi-variant binding/neutralization efficacy. This knowledge shows how mutational combinations can affect the binding or neutralization of an antibody, which in turn relates to the efficacy of immune responses to emerging SARS-CoV-2 escape variants. Molecular basis of SARS-CoV-2 Omicron variant evasion from shared neutralizing antibody response.,Patel A, Kumar S, Lai L, Chakravarthy C, Valanparambil R, Reddy ES, Gottimukkala K, Bajpai P, Raju DR, Edara VV, Davis-Gardner ME, Linderman S, Dixit K, Sharma P, Mantus G, Cheedarla N, Verkerke HP, Frank F, Neish AS, Roback JD, Davis CW, Wrammert J, Ahmed R, Suthar MS, Sharma A, Murali-Krishna K, Chandele A, Ortlund EA Structure. 2023 Jul 6;31(7):801-811.e5. doi: 10.1016/j.str.2023.04.010. Epub 2023 , May 11. PMID:37167972[4] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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