28. Calculate the overall net charge for the tripeptide leucine-lysine-histidine for pH = 1, 3, 5, 7, 10, and 12 given the following pKa values: amino-terminal amino 9.0; carboxy-terminal carboxyl 2.0; side-chain amino 10.5, and imidazole 6.0. Net charge at pH 1 = Net charge at pH 3 = Net charge at pH 5 = Net charge at pH 7= Net charge at pH 10 = Net charge at pH 12 = 29. What is pl for the tripeptide from previous question? 30. Draw the structure of this tripeptide (leucine-lysine-histidine) with the charges as it would exist at pH S. You do not have to depict the proper stereochemistry in the structure.

28. Calculate the overall net charge for the tripeptide leucine-lysine-histidine for pH = 1, 3, 5, 7, 10, and 12 given the following pKa values: amino-terminal amino 9.0; carboxy-terminal carboxyl 2.0; side-chain amino 10.5, and imidazole 6.0. Net charge at pH 1 = Net charge at pH 3 = Net charge at pH 5 = Net charge at pH 7= Net charge at pH 10 = Net charge at pH 12 = 29. What is pl for the tripeptide from previous question? 30. Draw the structure of this tripeptide (leucine-lysine-histidine) with the charges as it would exist at pH S. You do not have to depict the proper stereochemistry in the structure.

Introduction to General, Organic and Biochemistry

11th Edition

ISBN:9781285869759

Author:Frederick A. Bettelheim, William H. Brown, Mary K. Campbell, Shawn O. Farrell, Omar Torres

Publisher:Frederick A. Bettelheim, William H. Brown, Mary K. Campbell, Shawn O. Farrell, Omar Torres

Chapter22: Proteins

Section: Chapter Questions

Problem 22.69P

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