Indicate whether each of the following statements describes primary, secondary, tertiary, or quaternary protein structure:
b. Protein chains of collagen form a triple helix.

Question

Indicate whether each of the following statements describes primary, secondary, tertiary, or quaternary protein structure:

b. Protein chains of collagen form a triple helix.

Accepted Answer

All right. Hello everyone. So this question is asking to identify if the scenario below describes the primary secondary tertiary or quaternary protein structure. And the statement says three helical polypeptide chains tightly twisted around each other in a right-handed super helix option A says primary structure option B says secondary structure C says tertiary structure and D says ordinary structure. So very quickly, let's talk about the levels of protein structure. Proteins being three dimensional compounds are going to undergo a series of different interactions that are responsible for each protein's unique shape starting off with the primary structure, which is kind of like the blueprint, right. The primary structure refers only to the sequence of amino acids within the polypeptide chain. From there, those amino acids are going to interact with each other in different ways to produce the overall structure. So moving on now to the tertiary structure, excuse me, secondary structure, I skipped one secondary structure is characterized by localized folding. So what does that mean? Right, primarily localized folding refers to hydrogen bonding between atoms of the polypeptide chains backbone. In other words, the atoms of the peptide bonds that hold the chain together engage in hydrogen bonding to form a series of different structures. Those structures, if you recall include alpha helices and beta sheets. Moving on now to tertiary structure, the tertiary structure is categorized by the interactions between the amino acid side chains. Now, depending on the specific amino acid, right, their polarity and therefore, their properties are different, which results in a variety of different interactions between these amino acids. And because that secondary folding has already taken place in the tertiary structure of a protein amino acids that are far away from each other in the polypeptide chain can interact with each other. Now, at this point, it is the tertiary structure that determines the structure of one protein, one polypeptide chain. And so the ordinary structure applies only to proteins that have multiple subunits. The ordinary structure refers to interactions between the sub units. And again, this is only for proteins that have multiple sub units, not all of them do so. Now that we know more about the differences between each level of protein structure. Let's go back to the statement given it said the three helical polypeptide chains are tightly twisted around each other in a right-handed superhelix. So importantly, it's mentioning here, a superhelix between three polypeptide chains. This if you recall can be described as a triple helix or a collagen helix. This is characteristically a secondary protein structure and the reason it's called a collagen protein or collagen helix, excuse me is because it's found in collagen, it's what gives collagen its strength and stability. So once again, the answer is going to be option B in the multiple choice because that is secondary structure 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 whether each of the following statements describes primary, secondary, tertiary, or quaternary protein structure:
b. Protein chains of collagen form a triple helix.

Verified video answer for a similar problem:

Key Concepts

Protein Structure Levels

Collagen Structure

Helical Structures in Proteins

Indicate whether each of the following statements describes primary, secondary, tertiary, or quaternary protein structure:b. Protein chains of collagen form a triple helix.

Verified video answer for a similar problem:

Key Concepts

Protein Structure Levels

Collagen Structure

Helical Structures in Proteins

Indicate whether each of the following statements describes primary, secondary, tertiary, or quaternary protein structure:
b. Protein chains of collagen form a triple helix.