Question: What proteins are in our red blood cells, and how do they help?

Peter Elliott answered on 23 Jun 2014:

There are many proteins that are present in a red blood cell, mostly for structural and identification processes but possibly the most important one is the haemoglobin found in the middle of the red blood cell (rbc).

Haemoglobin is a protein that contains an iron atom. Because of the way the iron is placed within the haemoglobin it is able to bind oxygen. This is obviously very important as you probably are aware rbcs are used by the body to transport oxygen from the lungs to the rest of the body. Without rbc we wouldn’t be alive in our present state as we could not get enough oxygen through our bodies. The structure of haemoglobin means that it can carry four oxygen (O2) molecules, which is actually very efficient. However, if you happen to smoke you’ll find that your rbc cannot carry as much oxygen. This is because when you smoke a chemical called carbon monoxide enters your blood and competes with oxygen to bind to the rbcs. It actually binds a lot better than oxygen and is not released. So if you smoke you limit the amount of oxygen your blood can carry which is why often people who smoke cannot do so much sport.

As I mentioned their are also proteins used for recognition. These particular proteins we call antigens. Antigen are on the surface of all your cells and is a way for them to communicate with your immune system to let it know if the cell is from your body or a foreign body. This is important so that your immune system destroys unwanted cells whilst leaving your own cells to do their normal work.
You may have heard of the blood groups; A, B, AB and O. These are determined by the antigens on the surface of the rbc. Your immune system knows what type of rbcs your body produces and will target any rbcs that are not yours. That is why it is important when people get a blood transfusion doctors know the blood type of the donor and receiver as introducing the wrong blood can be fatal.

The final set of major proteins are structural. These help give the rbc its doughnut-like shape. This shape is optimal for the pick up and delivery of oxygen round the body.

Sorry that’s quite a long answer but I hope you find it helpful.