The recombinant 2019-nCoV Spike protein, called S1 (D614G) (16-685), is expressed in CHO cells through a C-terminal His-tag. The purity of this protein was found to be around 90% by densitometry, with a molecular weight of approximately 76 kDa.
The activity is recognized by analyzing the binding ability of the 2019-nCoV Spike protein RBD (D614G) to the immobilized human ACE2 (19-740) protein through a functional ELISA.
Globally, the novel coronavirus SARS-CoV-2 has resulted in the pandemic of respiratory diseases (COVID-19) in 2020.1 The spike glycoprotein (S) of a coronavirus is a type I transmembrane protein comprising two subunits—S1 and S2. This glycoprotein is known to attach with host cells via the interaction with angiotensin-converting enzyme 2 (ACE2).2
In the recent past, a SARS-CoV-2 variant that carries D614G mutation in the spike protein has turned out to be the most common form in the global pandemic. This G614 variant of spike protein has been experimentally linked to higher infectivity and clinically with greater viral loads in infected patients.3
The binding of 2019-nCoV spike protein (D614G) (C19S1-G231H) to human ACE2(19-740) protein (A51C2-G341F) was determined by ELISA. Image Credit: SignalChem Biotech Inc.
- Zhou P, et al: A pneumonia outbreak associated with a new coronavirus of probable bat origin. Nature. 2020, 579:270-89.
- Lan J, et al: Crystal structure of the 2019-nCov spike receptor-binding domain bound with the ACE2 receptor. Nature. 2020, 581:215-220.
- Korber B, et al: Tracking changes in SARS-CoV-2 Spike: Evidence that D614G increases infectivity of the covid-19 virus. Cell. 2020, 182:812-82.