Appropriately match each option to each description. Options m...

Question

Appropriately match each option to each description. Options may be used more than once.

a. Cyanogen bromide (CNBr). _____ An enzyme that cleaves specific peptide bonds.

b. Edman Degradation. _____ Nonspecifically cleaves all peptide bonds.

c. Elastase. _____ A chemical that breaks specific peptide bonds.

d. 6M HCl. _____ Used as an N-terminal protein sequencing technique.

_____ Used as a peptide cleavage technique.

_____ Results in smaller peptide fragments.

_____ Results in free amino acids.

Accepted Answer

Alright. So this practice problem wants us to match each option on the left over here with each description on the right. And it says that options may be used more than once. And the four options are cyanogen bromide, or CNBR, Edmond degradation, elastase, and 6 molar hydrochloric acid. Now 6 molar HCl and Edmond degradation should sound familiar to you guys from our previous lesson videos. But cyanogen bromide and elastase, we have not yet talked about. But just by looking at them a little bit closely, we can determine what they are. And so notice that cyanogen bromide or CNBR is really just a carbon atom, a nitrogen atom, and a bromine atom. And so really this is just a chemical, and indeed, it's used for chemical cleavage. Now elastase, on the other hand, ends with a s e. And so anything that ends in a s e is a good indicator that it's an enzyme. And, elastase is indeed an enzyme, more specifically, it's a peptidase, or an enzyme that cleaves peptide bonds. And so looking at our first description, an enzyme that cleaves specific peptide bonds, we know that multiple different reagents can be used to cleave specific peptide bonds, such as, many different types of chemicals and many many different types of peptidases. But because it specifically says enzyme, we know that it's referring to our peptidase here, elastase. And so we can go ahead and put option c for that description. Now the next description says, non specifically cleaves all peptide bonds. And the keyword here is actually all, because that eliminates cyanogen bromide and elastase, since we know they don't cleave all peptide bonds, they cleave very specific peptide bonds. And so we know that, 6 molar hydrochloric acid is used to induce amino acid hydrolysis, and that will non specifically cleave all peptide bonds. So for ops the next description, we can put d. Now the next one says, a chemical that breaks specific peptide bonds. And again, because it says specific peptide bonds, we know that it's not gonna be 6 molar hydrochloric acid. And because it says chemical, we know that it's not gonna be elastase, since elastase is not a chemical, it's an enzyme. And, of course, cyanogen bromide is the chemical that's going to be used to cleave these specific peptide bonds. So we can put option a for that description. Now the next, description says, use this n terminal protein sequencing technique. And there's only one protein sequencing technique that's listed here, and of course, that's Edmond degradation. And so we'll talk more about Edmond degradation later in our course, but for now, we can put option b for this description. Now the next one says, used as peptide cleavage technique. And it turns out that there's actually multiple different options for this one, because we know that cyanogen bromide is used as a peptide cleavage technique to cleave specific peptide bonds and so is elastase. It's a peptidase used to cleave specific peptide bonds. And also, 6 molar hydrochloric acid, even though it cleaves all of the peptide bonds, is still used as a peptide cleavage technique. So our answer for this one is actually going to be options a, option c, and Option D. Alright. So, the next description says, results in smaller peptide fragments. And so we know the fragments here is actually a key description, because that means that our peptide is being broken up into small pieces, but not all of the peptide bonds are being broken, which means that it's not gonna be 6 molar hydrochloric acid. But it is going to be either some type of peptidase, such as elastase, or some type of chemical, such as cyanogen bromide. And so we can go ahead and list either option a or option c are appropriate for this one. And then, of course, the last one says results in free amino acids. And that would mean that we cleave all of the peptide bonds. And so if we cleave all of the peptide bonds nonspecifically, we can generate free amino acids. And so that means that 6 molar hydrochloric acid is gonna be the correct option for this one, option d. And so that concludes this practice problem, and I'll see you guys in our next video.

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