Histidine is an important catalytic residue found at the active sites of many enzymes. In many cases, histidine appears toremove protons or to transfer protons from one location to another.(a) Show which nitrogen atom of the histidine heterocycle is basic and which is not.(b) Use resonance forms to show why the protonated form of histidine is a particularly stable cation.(c) Show the structure that results when histidine accepts a proton on the basic nitrogen of the heterocycle and then isdeprotonated on the other heterocyclic nitrogen. Explain how histidine might function as a pipeline to transfer protonsbetween sites within an enzyme and its substrate

Histidine is an important catalytic residue found at the active sites of many enzymes. In many cases, histidine appears toremove protons or to transfer protons from one location to another.(a) Show which nitrogen atom of the histidine heterocycle is basic and which is not.(b) Use resonance forms to show why the protonated form of histidine is a particularly stable cation.(c) Show the structure that results when histidine accepts a proton on the basic nitrogen of the heterocycle and then isdeprotonated on the other heterocyclic nitrogen. Explain how histidine might function as a pipeline to transfer protonsbetween sites within an enzyme and its substrate

Organic Chemistry

9th Edition

ISBN:9781305080485

Author:John E. McMurry

Publisher:John E. McMurry

Chapter21: Carboxylic Acid Derivatives: Nucleophilic Acyl Substitution Reactions

Section21.SE: Something Extra

Problem 35MP

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