Today, since we’re going to talk about Anfinsen’s experiments I thought I would talk about the interesting concept of renatured proteins.
I still think that this ability to renature after being denatured is a pretty amazing concept, almost paradoxical, simply because it’s like reversing the clock! I have always been fascinated with concepts like time-turning or stopping time, mostly because I wish that there were more hours in the day (Don’t we all!) Also, I feel like this is a fairly rare phenomenon in the physical world because many of our everyday actions seem irreversible. The following are a few examples of what I mean by “irreversible”:
1.When you fry an egg – you’ve essentially and completely altered your egg. There is no way you can go back to the point where the egg was raw (or liquid-y!)
2. When you burn a piece of paper there is no way you can (on this timescale) retrieve that same piece of paper – it’s gone and lost to the world, existing now as bits of ash and ember.
Essentially we can see it’s because the disruption of noncovalent interactions (and disulfide bonds) is much less impactful than the disruption of covalent bonds – in the sense that we can disrupt noncovalent interactions in proteins to denature them, yet they can reform. However, once we disrupt the covalent linkages between proteins, that’s when we’ve dug ourselves into a hole that is hard for us to reverse the process.
Main point of this rather abstract article is this – science is very humbling and try not to . mess with your covalent bonds.
I guess then that the conformation of proteins can be constantly altered (changing interactions) as in the egg example but if the bonds are being broken, the structure of the protein will never be the same as it once was anymore.
A very good point you’ve raised! I knew but I did not really assimilate that we only disrupted non-covalent interactions to denature proteins but left the covalent untouched. Non-covalent bonds really are resilient!
I can particularly imagine this topic being relevant to experimental design. Scientists have to constantly think of procedures that don’t interfere with covalent bonds of the protein of interest.