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COVID-19: N501Y mutant recombinant protein
COVID-19: N501Y mutant recombinant protein. China Yiqiao Shenzhou successfully expresses N501Y mutant recombinant protein again with high efficiency. After the announcement of the British mutant sequence, Yiqiao Shenzhou immediately started R&D and production, and quickly launched the N501Y mutant protein (Cat: 40592-V08H82) in only 10 days.
Recently, the emergence of new coronavirus mutants in the UK has attracted worldwide attention, such as “70% higher infectivity”, “London emergency lockdown”, “large numbers of people fleeing” and so on. In response to new variants of the new coronavirus, more than 40 countries have imposed entry bans on the UK. According to WHO, similar cases have appeared in 5 countries. On the 23rd, new strains of the virus also appeared in Israel, Singapore and Hong Kong SAR.
So how dangerous is the new strain? How much does the scientific community know about it?
The number of mutation sites in the UK mutants hit a record high
We combined the sequence of the new mutant strain uploaded by British scientists on virological.org and a report published in “Science” magazine, and the new strain temporarily named as B.1.1.7 subtype (the virus named “VUI- 202012/01”, that is, “the strains under investigation that appeared on December 1, 2020”) the known situation was sorted out.
Note: Cyan blue is 69-70 deletion, 145 deletion, royal blue is D614G, A570D, P681H, T716I, S982A, D1118H mutation, and yellow is N501Y mutation
The sequence uploaded by Andrew Rambaut of the University of Edinburgh points out that this new strain has 23 special mutations. This is the first time that so many mutations have been found in one strain. The sequence shows that the B.1.1.7 subtype is mutated on the basis of the widely popular D614G mutant strain. Among them, 8 mutations occurred on the spike protein Spike, including 69-70 deletion, 145 deletion, and N501Y, A570D, D614G, P681H, T716I, S982A, D1118H mutations; secondly, ORF8 and ORF1ab also had multiple mutations.
About the N501Y mutation
According to “Cell” report, the spike protein is the site of the new coronavirus that binds to the ACE2 receptor of human cells, and the spike protein Q493, Q498 and N501 site mutations will increase the affinity of the virus to the ACE2 receptor on the human cell surface, and enhance COVID-19 The infectivity of the virus. Therefore, scientists speculate that the infectivity of the mutant strain in the UK increased by 70%, which is most likely related to the N501Y mutation.
There are six key receptor contact residues in the receptor binding domain RBD of the spike protein, and N501 is one of them. In mouse models, experiments have confirmed that N501Y can enhance the binding affinity of the virus to human and mouse ACEs.
Recently, it has been reported that a new virus mutant appeared in South Africa, and the N501Y mutation was also found. The South African health department found that the mutant has three mutations in the receptor binding domain of the spike protein: K417N, E484K and N501Y. Among them, E484K and N501Y belong to receptor binding motifs, which are the main sites for binding to human ACE2 receptors.
(Source: GISAID, 3D structure of the COVID-19 Spike mutant)
Note: The left side is the ON state and the right side is the OFF state. The black is the mutation of D80A, D215G, the blue is the mutation of D614G, A701V, the yellow is the mutation of N501Y, E484K, K417N, and the green is the ACE2
However, whether the N501Y mutation will affect the infectivity of the mutated virus and its impact on the severity of the disease is still unknown, and more experiments are needed to verify it.
About 69-70 missing
The 69-70 deletion will result in the deletion of two amino acids at positions 69-70 of the spike protein. It has been found in multiple lineages of RBD-related mutations, such as the Danish mink mutant, where there are also 69-70 deletions. In some patients with weakened immune system, researchers found that this mutation may help the virus escape the host’s immune response. That is to say, the 69-70 deletion may cause the human immune system to fail to recognize the new coronavirus, so it is particularly important to strengthen the monitoring of the 69-70 deletion mutant.
Yiqiao Shenzhou successfully expresses N501Y mutant again at a high rate
After the announcement of the British mutant sequence, Yiqiao Shenzhou immediately started R&D and production, and quickly launched the N501Y mutant protein (Cat: 40592-V08H82) in only 10 days. The relevant purity test data are as follows:
South African mutant recombinant protein and recombinant protein S1 (△H69/△V70, N501Y, D614G) products containing 69-70 deletions are in hot schedule~
About the new coronavirus mutation
In July, Chinese scientists published a paper in “Cell” to systematically study and introduce the mutation of the new coronavirus, and identified 106 mutation sites from the known spike protein gene sequence. “Science” also has related reports, claiming that there are at least 200 differences in the virus strains in December, compared with the “first generation” new coronavirus.
In March, the D614G mutant strain became the main epidemic strain in Europe, increasing the infection rate of the virus by 2.4-7.7 times. Since then, most mutant strains have been mutated on this basis, such as the Danish mink mutation Y453F, and the recent British mutation N501Y and South African mutants.
Regarding mutants, people are concerned about whether their infectious ability is enhanced, and more attention is paid to whether the vaccine is still useful. Professor Wang Chenguang from China once wrote in “Is the mutation of the COVID-19 virus terrible?” The article pointed out that although the new British mutant strain has 8 mutations in the spike protein, it is less likely to cause larger protein conformation changes. “Science”, The Associated Press and other media also quoted the analysis of many experts that the mutation has little effect on the vaccine, but more experimental data are needed to confirm.
China Yiqiao Shenzhou has established the world’s leading novel coronavirus mutant antigen library, and currently has online RBD mutant recombinant proteins and more than 70 types, supporting researchers in research on the impact of mutant strains on the spread, clinical, diagnosis, vaccine and drug development of the new coronavirus .
(source:internet, reference only)