What is meant by the following terms as they apply to protein ...

Question

What is meant by the following terms as they apply to protein structure, and what bonds or molecular interactions stabilize that level of structure?

a. Primary structure

Accepted Answer

Hi, everybody. Let's look at our next problem. What is described by the primary structure of a protein, identify the types of bonds or molecular interactions that stabilize the structure. A, the primary structure is the overall three dimensional shape of the protein stabilized by covalent or non covalent side chain interactions. B the primary structure is the sequence or order of amino acids in a protein chain held together by peptide bonds. See, the primary structure is the organization of sub units to form a more complex protein unit held together by covalent or non covalent interactions or d the primary structure is the spatial arrangement of the peptide backbone stabilized by hydrogen bonds. So let's think about what a protein is and a protein is made up of a sequence of amino acids joined by peptide bonds in a chain. And if we can't remember which type of structure is, which let's think of going from the smallest level of organization to the largest. So if we're talking about primary structure, we want to talk about the lowest level of organization of our protein. So that would be the sequence of amino acids itself. Every protein has its own unique arrangement or order of amino acids, that signifies that specific protein. If you have a different arrangement of those amino acids, even if it's the same amino acids, if they're in a different order, you have a different protein. So this identifies the specific protein. And as we said in that chain of amino acids, each amino acid is linked to the next biopeptide bond. So that matches our choice B or the primary structure is the sequence or order of sub units or excuse me, the sequence or order of amino acids in a protein chain. And they're held together by peptide bonds. We'll just briefly look at our other answer choices to understand why they are not correct choice. A saying the primary structure is the overall three dimensional shape of the protein stabilized by covalent or non covalent side chain interactions. And this would be the tertiary structure. So two levels up, we have the primary structure, just the order in which the amino acids are and then the amino acid backbone, that backbone of the protein chain itself, the carbonyl oxygen and the hydrogen of the amy amid group can form hydrogen bonds between the backbone atoms themselves that forms structural units like alpha helices and beta sheets. That would be secondary structure. Then we have this overall three dimensional shape, often called the folding of the protein. And that's determined by interactions between the side chains. So the secondary level we're talking about interactions between the backbone atoms at the tertiary level, tertiary level, the interactions between side chain atoms and that is covalent or non covalent interactions between them. So there can actually be bonds formed like diy vte bridges or just hydrogen bonds or dipole interactions. Choice C So that's why choice A is incorrect. Since that's tertiary choice C says the primary structure is the organization of sub units to form a more complex protein unit held together by covalent or non covalent interactions. Well, this is the highest level of organization, the quaternary structure because sometimes we have multiple peptide chains coming together to make a protein. So a protein isn't necessarily just one chain of amino acids. It can be multiple subunits together as in hemoglobin where you have four subunits. So you need to describe that level how the different chains are put together. So choice C not our correct answer. And then finally, choice t the primary structure is a spatial arrangement of the peptide backbone stabilized by hydrogen bonds and that would be secondary structure. So hydrogen bonding between the atoms of the protein backbone forms the secondary structure of the protein. So that's why choice D is not correct. So once again, primary structure of the protein and the types of bonds or interactions that stabilize it. This choice B it's the sequence or order of amino acids in a protein chain and they're held together by peptide bonds. See you in the next video.

Struggling with GOB Chemistry?

What is meant by the following terms as they apply to protein structure, and what bonds or molecular interactions stabilize that level of structure?
a. Primary structure

Watch next

Primary Protein Structure practice set

Struggling with GOB Chemistry?

What is meant by the following terms as they apply to protein structure, and what bonds or molecular interactions stabilize that level of structure?a. Primary structure

Watch next

Primary Protein Structure practice set

What is meant by the following terms as they apply to protein structure, and what bonds or molecular interactions stabilize that level of structure?
a. Primary structure