The correct answer is option [E]. Aspartic acid is protonated at the beginning o
ID: 699776 • Letter: T
Question
The correct answer is option [E].
Aspartic acid is protonated at the beginning of reaction cycle in aspartyl process. The group similar to this function is Aspartic Acid 102.
Since asparate is acidic, it will be deprotonated first by bases. Aspartate that flanks the histidine residue also provides it with favorable electrostatic effects and makes it a better proton acceptor. So after asparate is deprotonated, proton transfer from histidine goes to aspartate. Now that histidine is deprotonated, it grabs the proton from serine's hydroxyl group. This creates a much more reactive alkoxide group on serine.