Researchers at the Harbin Institute of Technology, China, found that the N439K mutant of SARS-CoV-2 virus binds more strongly with ACE-2 receptor cells than the original Wuhan strain.
The spike protein of the virus binds with the ACE-2 receptor to proliferate through the body and infect more cells. This spike is countered by the immunising antibodies produced by the host immune system to disrupt virus’s binding.
However, the efficacy of the antibodies may get disrupted due to the mutations. Currently, there are about 930 mutations reported worldwide. A mutation from ASP614 to GLY614 has made the virus more infectious, according to a report published in the journal News Medical and Life Sciences.
Earlier coronavirus infections, including SARS and MERS, showed a similar kind of resilience after their mutation.
Thus, researchers speculated that mutations in SARS-CoV-2 may also lead to strains that are resistant to the antibody treatments that are being developed.
Hence, it is necessary to monitor mutations in the circulating SARS-CoV-2 strains to develop better therapeutics, the researchers believe.
The molecular dynamics simulations carried out by the researchers showed more flexibility changes in the N439K variant, which could result in structural rearrangements in the SARS-CoV-2 RBD-ACE2 complex that led to a stronger binding.
Furthermore, the complex with the mutated virus forms more hydrogen bonds than the wild-type complex.
The researchers mentioned that although previous studies have suggested mutant versions of the virus may be less infectious, the stronger binding of human ACE2 with the N439K mutant suggests this mutant strain may be more infectious.
The N439K mutation is completely included in the D614G samples, which have been observed to be more infectious than the original strain.
The researchers reported their findings in a paper published in the journal bioRxiv* preprint server.