A portion of a polypeptide chain contains the following sequence of amino acids:
—Leu—Val—Cys—Asp—
c. How does the primary structure of a protein affect its tertiary structure?

Question

A portion of a polypeptide chain contains the following sequence of amino acids:

—Leu—Val—Cys—Asp—

c. How does the primary structure of a protein affect its tertiary structure?

Accepted Answer

All right. Hello everyone. So this question says that a segment of a protein consists of the following amino acid sequence. We have iso lucine phenylalanine thine and aspartic acid based on their properties, identify the amino acids found in the interior and exterior of the protein. What is the relationship between a protein's primary structure and its tertiary structure? So let's actually begin with the second part of the question. What is the relationship between the primary and tertiary structures of a protein? Well, recall first and foremost that the primary structure of a protein simply refers to the sequence of amino acids that are going to eventually make up the protein. So for example, the amino acid sequence that we're given is an example of primary structure. Now, on the other hand, the tertiary structure of a protein is the three dimensional structure of the protein unit. And so depending on the amino acids that are present and the interactions between those amino acids, the primary structure ultimately is going to in part dictate the unique tertiary structure of the protein. This is because once again, the amino acids that are present are going to affect the interactions and therefore folding patterns that result in the tertiary structure. So how do we determine then the relationship between interior and exterior proteins in that 3d shape? Well, here recall that amino acids have different polarities to them. We can talk about polar neutral amino acids, we can talk about polar charged amino acids. The in other words, the acidic or basic amino acids and we can just talk about nonpolar amino acids. Now, the polar, neutral and polar charged amino acids are both hydrophilic, whereas nonpolar amino acids are hydrophobic. Now, in this particular case, a protein that's going to be present in our body is more than likely going to be surrounded by aqueous extracellular fluid or aqueous intracellular fluid. And so the idea here is for the protein to have favorable interactions with its environment so that it can blend in well, right, it can dissolve well in its environment. And so because this this environment that's outside of the protein is aqueous and therefore polar, the hydrophilic amino acids are more commonly found or more likely to be found on the outside. Whereas the hydrophobic amino acids are more likely found on the inside away from that aqueous environment. And so with this in mind, let's talk about the specific amino acids that were given here. Once again, we have isoleucine, pheno alanine, thine and aspartic acid or aspartate. If you recall isoleucine and phenyl alanine are examples of nonpolar amino acids because their side chains are hydrocarbon groups. On the other hand, thine is a polar neutral amino acid because its side chain contains a hydroxy group. And aspartic acid or aspartate is an example of a polar charged amino acid because it's an acidic amino acid. Therefore, it would have a negative charge on the side chain. So all this is to say that thine and aspartic acid are hydrophilic and isol loin and pheno alanine are hydrophobic. Therefore, thine and aspartic acid are found on the outside or are likely to be found on the outside. While isoleucine and phenylalanine are more likely found on the inside of the three dimensional protein and there you have it. So now we've arrived at our final answer which I've placed here at the bottom of the screen. It says that isoleucine and phenylalanine are likely to be found in the interior of the protein. While renin and aspartic acid are likely found on the exterior of the protein. The primary structure dictates the specific interactions and folding patterns that result in the unique tertiary structure of the protein. And so with that being said, thank you so very much for watching. And I hope you found this helpful.

A portion of a polypeptide chain contains the following sequence of amino acids:
—Leu—Val—Cys—Asp—
c. How does the primary structure of a protein affect its tertiary structure?

Verified video answer for a similar problem:

Key Concepts

Primary Structure of Proteins

Tertiary Structure of Proteins

Structure-Function Relationship

A portion of a polypeptide chain contains the following sequence of amino acids:—Leu—Val—Cys—Asp—c. How does the primary structure of a protein affect its tertiary structure?

Verified video answer for a similar problem:

Key Concepts

Primary Structure of Proteins

Tertiary Structure of Proteins

Structure-Function Relationship

A portion of a polypeptide chain contains the following sequence of amino acids:
—Leu—Val—Cys—Asp—
c. How does the primary structure of a protein affect its tertiary structure?