Mutations: A new life? The emergence of SARS-CoV2

I came across this article from The Indian Express which tells us about the frequent mutations taking place in SARS-CoV2.

"Dr Dhiraj Paul of NCCS, the lead author of the study, said due to frequent mutations, the novel Coronavirus was able to modify itself into different sub-types in a very short period of time.

“In our study, we have found newly-evolved mutation pattern and sub-type which is not yet reported from any other part of the country. This sub-type has reached almost 50 per cent in our study population in Maharashtra."

They found specific age-wise patterns of mutations similar in different age groups!

A few days back in one of the CUBE Chatshaalas, we were discussing about the mutations taking place in the SARS-CoV2 and we also discussed the ancestry of this virus.

This directly hints towards evolution! There’s a lot of talk on how the virus emerged suddenly from bats and has now become a pandemic.
How does this virus and its ability to infect differ from SARS-CoV (2003) and possibly MERS-CoV (2012)?

Now there is an opportunity for us to actually make a proposition on what is actually happening to the virus which is giving rise to frequent mutations? and the fate of the mutation!

Please read this article and let us follow-up with a discussion leading to a proposition which shall help us in decoding some myths and will also help us in understanding the current situation!

Post Script:- SARS-CoV (2003), MERS-CoV (2012) and SARS-CoV2 (2019) belong to the family of Coronaviruses but differ a lot when seen closely (through literature :stuck_out_tongue_winking_eye:).
The example of earlier two viruses is just given as a reference.

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Could you briefly state the differences and the refrences. The litreature I refer to which is mainly about methods of filtration of the virus or disruption of infectivity or destruction of the virus suggests that the covid family are very similar wrt to efficacy of such methods.

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Most of the findings are discussed in two articles posted as:

Regarding the differences of SARS-CoV and SARS-CoV-2, it is said that the latter has evolved into developing stronger affinities to the ACE receptors than the former one…

SARS-CoV-2 being a RNA virus has a higher mutation rate than those compared with DNA virus…

You may also want to read a related post:

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Similarities between SARS-CoV (2003) and SARS-CoV2 (2019)
→ Both SARS-CoV (2003) and SARS-CoV2 (2019) belong to the family of Coronaviruses.
→ They are SARSs (Severe Acute Respiratory Syndromes), both affect the respiratory tract of the host.
Both share around 70-80% of their genome (total gene sequence).
→ Both the viruses use the ACE-2 (Angiotensin-converting enzyme-2) receptor to enter the host’s cells.

Differences between SARS-CoV (2003) and SARS-CoV2 (2019):
SARS-CoV2 shares around 70-80% of its genome with SARS-CoV, but the former shows to have the highest level of similarity with a horseshoe bat coronavirus"
SARS-CoV2 is thought to be a recombinant virus transmitted from bats to human hosts by the mean of an intermediate host

Reference: https://www.europeanreview.org/wp/wp-content/uploads/2781-2783.pdf

SARS-CoV-2 is closely related to two bat-derived severe acute respiratory syndrome-like coronaviruses, bat-SL-CoVZC45 and bat-SL-CoVZXC21.

Reference: https://pubmed.ncbi.nlm.nih.gov/32081636/

SARS-CoV-2’s (2019) Spike protein is longer than SARS-CoV (2003) Spike protein (embedded in the lipid envelope) and its receptor binding region is different.
→ Also, the SARS-CoV nucleocapsid protein has the ability to neutralize the immune response of the host, it is not known if SARS-CoV-2 N protein shares the same ability.

Reference:
Genomic characterisation and epidemiology of 2019 novel coronavirus: implications for virus origins and receptor binding. Lancet 2020; 395: 565-574.
https://www.thelancet.com/article/S0140-6736(20)30251-8/fulltext

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Yes, I did have a look at these threads. They have useful references.
The findings (on the frequent mutations of the virus) in the article from The Indian Express was eye-catching for me, so I thought that I will create a new thread from where I shall get inputs from everyone!

Thanks for the link! :raised_hands:

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In the past 3 months (and even now), we have been seeing that new strains of the SARS-CoV are (re)emerging.
Why is it that these strains are emerging all of a sudden?
This (alongwith few other) question(s) come in my mind when I hear about new strains!
I am pretty sure that the possible answer or even something close to the answer will be interesting to know.

Why didn’t the CoronaViruses that broke out in 2003 as SARS-CoV and in 2012 as MERS-CoV continue for so long…?
Even though SARS-CoV2 has a better affinity towards the ACE2 (angiotensin-converting enzyme 2) receptor and now too it is mutating and is on the verge of creating a new phenotype, why didn’t it happen with the viruses that emerged earlier?

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We at Commons have compiled the timeline of the new strains and related evidence to the vaccine efficacy.

https://common.page/covid-19/Variants

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ALONG WITH THE ORIGIN OF SARS COV 2 LETS ALSO DISCUSS THE IMMUNE RESPONSE
What do we mean by an immune response? When an antigen for example coronavirus invades a body. The cell like macrophage by the process of phagocytosis engulf the antigen and break it down, it is an antigen presenting cell, that is the parts of the antigen will be presented by macrophage. this presented antigen can be recognised by T helper cell which can signal more T cell to kill the antigen (helper T cell will produce cytotoxic T cell) The helper T cells will of course from memory T cells. So if the same antigen invade again the response will be comparatively faster as the memory cell can recognise the antigenWhatsApp Image 2021-05-16 at 10.07.38 PM

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WhatsApp Image 2021-05-16 at 10.07.40 PM
Another type of response is Through B cells. B cells can bind to the antigen through antigen receptor which will activate the B cell and there would be the production of the antibody also memory B-cell will be formed so if the same antigen is invading at the time The memory B-cell can recognise the antigen and start producing antibodies

WhatsApp Image 2021-05-16 at 10.07.42 PM

How does coronavirus infect humans? coronavirus with the help of its spike protein binds to a human cell receptor, leaving the out of phone behind it transfers its genetic material that is RNA inside the host (human) cell. This genetic material is +ve RNA is used as a template by viral RNA polymerases to produce -ve RNA Which is further used as a template for +ve RNA which can be used as core RNA (genetic material)It further gets translated to produce coat protein

Antibody test Are carried out especially for plasma therapy so that the antibodies can be transferred to another patient suffering from Covid 19. How is this antibody test carried out?

We also discussed what are antibodies Antibody is a protein that binds to antigen and neutralises it The first step of infection by coronavirus is the outer protein coat the spike protein binds to the (human cell)receptor. So if a vaccine is developed of this spike protein we can produce antibody against this spike protein And hence the infection will not start in the first place that is the coronavirus will never be able to invade our cells because the spike proteins are bounded with antigenWhatsApp Image 2021-05-16 at 10.07.45 PM

(How Bharat Biotech’s Covaxin Vaccine Works - The New York Times)

Vaccines are helping us produce antibodies against coronavirus and memory cells Which can recognise the antigen then why does it happen so that some people after taking vaccines get affected by coronavirus?
There could be several reasons to it!
one could be that immune response is developed over a period of time and that differs from person to person so in case the corona virus infects before the immune response is generated the person will get affected by COVID
so if the coronavirus invade the body before the immune response is generated by vaccine, is the case more dangerous? as the immune system will be encountering both the vaccine as well as the coronavirus!
Also one important point in the discussion was that precaution is very necessary in this period of pandemic even if you take vaccines you should still continue to take precautions because immune response may develop over a period of time and in that period coronavirus can infect you