Indicate what type(s) of intermolecular forces are disrupted a...

Question

Indicate what type(s) of intermolecular forces are disrupted and what level of protein structure is changed by the following denaturing treatments:

a. an egg placed in water at 100 °C and boiled for 10 minutes

Accepted Answer

Alright, hello everyone. So this question is asking us what type or types of ancient molecular forces are primarily affected and which level or levels of protein structures are altered when brewing coffee at 90 °C. So here on the screen, we also have four different answer options labeled A through D proposing different possible interactions and also different levels of protein structure that could be affected. So first, let's gain a little bit of context into what kinds of information we need to know for this question right now, recall first and foremost that there are multiple different types of intermolecular forces or IMF s for short, that work to stabilize proteins. Some examples include hydrogen bonds or H bonds as I'm writing here on the screen. But we can also see things like ionic bonds. These can otherwise be referred to as salt bridges. But we can also see van der Waals forces and we can also see even hydrophobic interactions. And so these are the kinds of intermolecular forces that we think about when trying to answer a question like this. So the question now is which ones are vulnerable to the change described in the question. Now, the change just so we're clear is this high temperature, which I MFS are vulnerable to this high temperature at 90 °C. And the answer would be numbers one and four, right, because hydrogen bonds and hydrophobic interactions are both vulnerable at higher temperatures because of the increased molecular motion associated with these high temperatures. And so now that we have a sense of what interactions are vulnerable, what levels of protein structure are going to be affected? So let's talk about the levels very quickly starting off with primary structure. Primary structure put simply is simply the sequence of amino acids that make up a polypeptide. And so because of this is characterized bi covalent bonds between peptides are peptide bonds. These are not typically disrupted by heat. So we're not going to see a change in primary structure. Now, on the other hand, secondary structure is characterized by intermolecular forces within that peptide bond backbone that was created after primary structure or after the primary structure was completed. So just to reiterate secondary structure is characterized by intermolecular forces within the atoms of the peptide bond backbone to create structures like alpha helices and beta sheets. And so this level of protein structure is characterized by H bonds because hydrogen bonds are what create these structural elements, these alpha helices and beta sheets. So secondary structure is vulnerable to high heat. So now tertiary structure now taking things a step further is characterized by intermolecular forces within or actually, I should say between its intermolecular forces between amino acid side chains. And so the tertiary structure is what results in the mature three dimensional shape of a polypeptide. Because the amino acid side chains can be classified in different ways depending on their polarity. We can see the four different types of IMF S that we talked about earlier h bonds, ionic bonds, vander Waals forces and hydrophobic interactions. All of these are possible in tertiary structure, which means that tertiary structure is also vulnerable to high heat. And last but not least, we have ordinary structure, which is really only applicable to specific proteins that are made up of multiple subunits. Because in ordinary structure, we talk about the IMF between individual subunits to create that larger complete protein. So not every protein has a ordinary structure but for the proteins that do have ordinary structure, they're stabilized by the same forces as tertiary structure, which means that it is also vulnerable to high heat. So therefore, our answer is going to be option a in the multiple choice because the IMF vulnerable to high heat are hydrogen bonds and hydrophobic interactions, which means that secondary tertiary and ordinary structures are vulnerable to this change and there you have it. So with that being said, thank you so very much for watching and I hope you found this helpful

Indicate what type(s) of intermolecular forces are disrupted and what level of protein structure is changed by the following denaturing treatments:
a. an egg placed in water at 100 °C and boiled for 10 minutes

Key Concepts

Intermolecular Forces

Protein Structure Levels

Denaturation

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