An explanation of how it works.
The featured image is of a cell with hundreds of Corona viruses over it.
Where it all started
The renin -angiotensin system. This is all about enzymes – proteins that convert one thing into another thing like – starch to sugars – sugars to fats – etc,etc
If you get attacked by a large animal and lose lots of blood, one of your greatest risks is that your kidneys will fail and you will die because there is not enough blood going through your kidney to work the filter system.
The good thing is that when the kidney detects the inevitable drop in blood pressure it releases Renin. Renin is an enzyme in the kidney that makes Angiotensin 1. There’s always a bit of Renin around to make Angiotensin 1, so there’s always a bit of Angiotensin 1 around.
Angiotensin 1 is a hormone that at the blood vessel level causes a mild rise in blood pressure. That’s handy because the mild rise in blood pressure keeps the kidney working somewhat when you bleed a lot.
Now Angiotensin 2 comes into play
In the lung is another enzyme that converts Angiotensin 1 to Angiotensin 2. It’s called Angiotensin Converting Enzyme. It must be largely stuck to lung cells, but probably breaks free to float around in the serum. The Angiotensin Converting Enzyme makes Angiotensin 2 from Angiotensin 1. Angiotensin 2 is much more powerful at raising the blood pressure. So if you are bleeding, you maintain kidney blood flow and don’t accumulate toxins like creatinine. Over the past 35 years research has been to find medications that block the conversion of Angiotensin 1 to Angiotensin 2 – the ACE inhibitors. You or your parents or your grandparents are on them. They are fantastic for blood pressure control, and also protect the heart and blood vessels from damage. Good stuff.
On the other hand
But nature has a way of balancing things out. There is also an enzyme stuck to the cells that line the inside of the lung, gut and blood vessels (including the heart) that move things back the other way. This is the Angiotensin Converting Enzyme type 2. (ACE2) It makes Angiotensin 1 from Angiotensin 2. It also makes Angiotensins 3,4,5,6,7,8,9. Some of the enzymes are ok, some are dangerous. The Angiotensin Converting Enzyme type 2 (ACE2) can come unstuck from the cell surface and float around the body.
And that’s not all.
The coronavirus has little things all over its sphere. Little fingers. Little antennae. They are often called spikes, but they are far from spiky most of the time; more of a club.
At the end of the club shaped spike are three sugary proteins. That accounts for it sticking to stainless steel, copper, anything. A sticky sugar,
Anyway, the sugars break off and leave the spike exposed. It now looks like more the spike on a flu virus.
The spike has a protein on its end called Protein S. S for where it is – the end of the spike. It’s got a zinc atom involved there somewhere and that may increase its stickiness.
Either way, the important thing is that the coronavirus has a protein on the end of its spike, antenna, finger that looks like a mirror image of the Angiotensin Converting Enzyme type 2 (ACE2). It’s called Protein S. So part of the virus Protein S binds with the Angiotensin Converting Enzyme type 2 (ACE2) protein on the surface of the cell.
What the virus does next
The virus has a weak spot nearby that gets dissolved by passing enzymes, and so it breaks. My guess is that this causes the host cell membrane to break as well and allow the entry of viral RNA (Genetic material) into the cell where it encourages the cell to make more ACE2 proteins on its outside for more viruses to stick to and enter from the outside. And so on.
This all changes the structure of the cell and makes the cell more specialized.
Non-specialized cells are the least likely to be infected by the virus. Highly specialized (highly differentiated) cells are much more likely to be adversely affected. With a high level of specialization comes a poor tolerance of this new attack and the virus is not called a novel coronavirus for nothing.
The coronavirus also increases messenger RiboNucleic Acid (mRNA) – the messenger that makes more viral RNA for more copies of the virus RNA (genetic material).
Finally, the virus causes the release of destructive inflammatory enzymes and hormones that destroy the cell and the virus’s hundreds of progeny then exit trough the ruptured tip (apex) of the lung surface cell to be breathed out into the air where they can last for hours.
and so it goes.