SARS-CoV-2 Recombinant Proteins

SARS-CoV-2 is the causative viral agent of the disease COVID-19. It bears several key proteins within its structure which have been the focus of research the past number of months due to their potential to be therapeutic targets in COVID-19.

The spike protein is the one of the four main proteins found on the surface of the coronavirus virion. These transmembrane glycoprotein spikes consists of two components; S1 and S2. S1 and S2 proteins have been shown to play a major role in receptor binding and membrane fusion. The receptor-binding domain (RBD) of the S protein can be found at the N-Terminal end of the S1 domain. It is responsible for host cell entry of the virus via the ACE2 receptor. Upon binding of the Spike S1 domain to ACE2 a conformational change is initiated in the Spike S2 domain; this facilitates the attachment of the virus to the host cell membrane which results in subsequent nucleocapsid transfer into cell.

Angiotensin II converting enzyme (ACE2), a carboxypeptidase, is an enzyme involved in the renin-angiotensin system (RAS). It has been shown to play an important role in regulating the heart function. ACE2 is a receptor of human coronaviruses, such as SARS and HCoV-NL63. This receptor facilitates the uptake of SARS-CoV-2 into host cells. ACE2 is expressed in multiple locations and cell types, notably including alveolar epithelial cells, surface enterocytes within the small intestine, and vascular endothelial cells of the lung, kidneys and heart.

Coronavirus N protein is the most abundant protein expressed on the surface of the coronavirus. It is required for coronavirus RNA synthesis and packaging, and has RNA chaperone activity that may be involved in template switch. The N has also been suggested to play a role in virus particle release.

The envelope protein is one of the four integral proteins found on SARS-CoV-2 viral particles. The protein has a central role in virus morphogenesis and assembly, acting as a viroporin and self-assembling in host membranes to form pentameric protein-lipid pores that allow ion transport. The E protein also plays a role in the induction of apoptosis (by similarity).

With the rapid progression of the global pandemic, COVID-19, over the past number of months, there must come innovative drug development and research strategies to battle and overcome this infectious disease.

At ELISA Genie we have developed 58 novel recombinant proteins to aid COVID-19 Research.

Our proteins are highly pure, ranging between 90-98% in purity. They are also physiologically relevant; ELISA Genie recombinant proteins are expressed in mammalian expression systems, meaning that they are synthesized, processed, and secreted in a manner similar to in humans. For this reason, as well as the fact they have been shown to have low endotoxin, our recombinant proteins do not elicit an immune response in vivo. This makes ELISA Genie recombinant proteins hugely relevant to the area of vaccine development for COVID-19.

We have synthesized recombinant versions of the key proteins involved in the process of viral infection by COVID-19. These include the integral proteins expressed on the surface of the coronavirus; spike (S) protein, envelope (E) protein, and nucleocapsid protein (N).We have also created recombinant proteins of other proteins involved in the mechanism of infection with coronavirus. These include proteinases, proteases, and helicases essential for coronaviral replication and host cell invasion, as well as human proteins implicated in coronavirus uptake into host cells, such as CD147/Basigin Protein, APN Protein, and the human receptor for SARS-CoV-2; ACE2,

Our recombinant proteins allow scientists to both recapitulate the endogenous activity of key proteins involved in coronavirus infection, as well as develop potential therapies by targeting such proteins.