ジャーナル: Nat Commun / 年: 2020 タイトル: Selection, biophysical and structural analysis of synthetic nanobodies that effectively neutralize SARS-CoV-2. 著者: Tânia F Custódio / Hrishikesh Das / Daniel J Sheward / Leo Hanke / Samuel Pazicky / Joanna Pieprzyk / Michèle Sorgenfrei / Martin A Schroer / Andrey Yu Gruzinov / Cy M Jeffries / Melissa A ...著者: Tânia F Custódio / Hrishikesh Das / Daniel J Sheward / Leo Hanke / Samuel Pazicky / Joanna Pieprzyk / Michèle Sorgenfrei / Martin A Schroer / Andrey Yu Gruzinov / Cy M Jeffries / Melissa A Graewert / Dmitri I Svergun / Nikolay Dobrev / Kim Remans / Markus A Seeger / Gerald M McInerney / Ben Murrell / B Martin Hällberg / Christian Löw / 要旨: The coronavirus SARS-CoV-2 is the cause of the ongoing COVID-19 pandemic. Therapeutic neutralizing antibodies constitute a key short-to-medium term approach to tackle COVID-19. However, traditional ...The coronavirus SARS-CoV-2 is the cause of the ongoing COVID-19 pandemic. Therapeutic neutralizing antibodies constitute a key short-to-medium term approach to tackle COVID-19. However, traditional antibody production is hampered by long development times and costly production. Here, we report the rapid isolation and characterization of nanobodies from a synthetic library, known as sybodies (Sb), that target the receptor-binding domain (RBD) of the SARS-CoV-2 spike protein. Several binders with low nanomolar affinities and efficient neutralization activity were identified of which Sb23 displayed high affinity and neutralized pseudovirus with an IC of 0.6 µg/ml. A cryo-EM structure of the spike bound to Sb23 showed that Sb23 binds competitively in the ACE2 binding site. Furthermore, the cryo-EM reconstruction revealed an unusual conformation of the spike where two RBDs are in the 'up' ACE2-binding conformation. The combined approach represents an alternative, fast workflow to select binders with neutralizing activity against newly emerging viruses.
Locally refined focussed map on the C and F chain interaction. ResolveCryoEM from the Phenix suite generated the map from the respective half maps in the local refinement in CryoSparc.