Amide...?

[AWolfman]

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Where is the amide group in this bad boy?
Answer says water (normally in the place of glycine) is made more nucleophilic by deprotonation to make the carbonyl carbon of the amide group more electrophilic.

 

[cwillman044]

This might be very wrong but I think its referring to the amide and carbonyl on glutamate 148.
Edit: just kidding, glutamate definitely doesn't have an amide group

 

[aldol16]

This might be very wrong but I think its referring to the amide and carbonyl on glutamate 148.
Edit: just kidding, glutamate definitely doesn't have an amide group

Yes it does. Because the residues are numbered, that means they are part of a polypeptide backbone, which must be linked via amide bonds. However, I'm not sure whether that's what the passage is referring to.

OP, I believe this is a zinc metalloprotease so the amide they are referring to should be the scissile amide bond, which may not be shown in this figure.

 

[cwillman044]

Yes it does. Because the residues are numbered, that means they are part of a polypeptide backbone, which must be linked via amide bonds. However, I'm not sure whether that's what the passage is referring to.

OP, I believe this is a zinc metalloprotease so the amide they are referring to should be the scissile amide bond, which may not be shown in this figure.

ahh I see, I'm partially right for all the wrong reasons even though I think I'm wrong. Such is life for the MCAT.

 

[popopopop]

Where was this from again? I did this passage. SB?

 

[AWolfman]

C/P section bank

 

[popopopop]

Alright, here's my stab at it. So the first sentence stated in the passage stated "Human acylase-1 (hAcyl) is a homodimeric enzyme that catalyzes the hydrolysis of the terminal peptide bond in a protein or the hydrolysis of N-acyl amino acids." What we're looking at in the picture is the enzyme aminoacyclase, which does the following.

The passage also stated "The proposed mechanism of action by hAcyl involves binding of the substrate, deprotonation of the bound water by a glutamate at position 147 (not shown), and subsequent reaction with the substrate." This is basically where I got the answer from for the question, and I basically stopped there.

Here's the proposed mechanism from wiki and you can see how glutamate is interacting with aminoacyclase, and that deprotonated water is now the hydroxide and attacking the carbonyl carbon.

https://en.wikipedia.org/wiki/Aminoacylase

 

[Formation]

The enzyme hydrolyzes amide bonds, so the amide they're referring to isn't in the structure of the enzyme but in the structure of the substrate.