Connections between biomechanics and higher infectivity: a tale of the D614G mutation in the SARS-CoV-2 spike protein

Mutations are known to play a critical role in how a species evolves.In a recent article that appeared in the journal Cell,Yurkovetskiy et al.1 reported the structural and functional properties of the SARS-CoV-2 spike protein variant D614G that explains the basis of its increased infectivity.They observed that the mutant(D614G)was 4 to 9-fold more infectious than the wild type(D614),and the increased infectivity was not limited to human angiotensin-converting enzyme 2(ACE2).1 The cryo-EM structure suggested that D614G mutation weakens the stability of the homotrimer that shifts protein conformation towards an ACE2-binding fusion-competent state.1 The authors additionally showed that the D614G variant is neutralized by monoclonal antibodies targeting the spike protein receptor-binding domain(RBD).