00:03
Hi there.
00:03
This question is about the tertiary structure of proteins, and the tertiary structure comes from interactions of the side chains on the amino acids.
00:27
And there are four basic types of interactions.
00:34
There are the hydrophobic interactions.
00:42
In other words, the interactions between non -polar portions.
00:47
Those are going to be on the inside of the protein structure, because they are trying to stay away from water.
00:59
So we're going to have hydrophobic interactions.
01:03
We will, of course, have hydrogen bonds, which could be thought of as hydrophilic.
01:11
Because hydrogen bonds, of course, love water.
01:16
There are salt bridges, so ionic bonding, and disulfide, covalent bonds.
01:30
So bonds between two sulfurs.
01:33
So a sulfur to sulfur covalent bond.
01:42
All right, so these would be the four types of bonds we see.
01:45
Well, this question asks which of these following is not responsible for the stability.
01:52
So we have a, b, c, and d.
01:56
A is, basically, it's none of the above, but it's at the start.
02:00
So we'll have to come back to that after we look at b, c, and d.
02:04
So we want to know which are not responsible...