1.Histidine has three ionizable functional groups. Write the equilibrium equations for its three ion-izationsand assign the proper pKa for each ionization. Draw the structure of histidine in each ionization state.What is the net charge on the histidine molecule in each ionization state? 2.Which structure drawn in (1) corresponds to theionization state of histidine at pH 1, 4, 8, and12?Note that the ionization state can be approximated by treating each ionizable group independently. 3.What is the net charge of histidine at pH 1, 4, 8, and 12? For each pH, will histidine migrate to-ward the anode (+) or cathode (-) when placed in an electric field?

1.Histidine has three ionizable functional groups. Write the equilibrium equations for its three ion-izationsand assign the proper pKa for each ionization. Draw the structure of histidine in each ionization state.What is the net charge on the histidine molecule in each ionization state? 2.Which structure drawn in (1) corresponds to theionization state of histidine at pH 1, 4, 8, and12?Note that the ionization state can be approximated by treating each ionizable group independently. 3.What is the net charge of histidine at pH 1, 4, 8, and 12? For each pH, will histidine migrate to-ward the anode (+) or cathode (-) when placed in an electric field?

Biochemistry

6th Edition

ISBN:9781305577206

Author:Reginald H. Garrett, Charles M. Grisham

Publisher:Reginald H. Garrett, Charles M. Grisham

Chapter31: Completing The Protein Life Cycle: Folding, Processing, And Degradation

Section: Chapter Questions

Problem 17P

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