1. a) Classify the amino acids according to the nature of their side chains (R groups), stating which are polar, non-polar, acidic and basic. Draw the structure of the amino acid glutamic acid in neutral solution at pH7.0. b) What is meant by the term isoelectric point of an amino acid? Discuss how is it related to the pKa values of an amino acid? c) What practical technique would you use to separate a mixture of the amino acids arginine, valine and glutamic acid? State briefly how it works. d) Describe in detail the two analytical methods that can be used to separate a complex mixture of proteins, yielding individual proteins with different amino acid sequences.

1. a) Classify the amino acids according to the nature of their side chains (R groups), stating which are polar, non-polar, acidic and basic. Draw the structure of the amino acid glutamic acid in neutral solution at pH7.0. b) What is meant by the term isoelectric point of an amino acid? Discuss how is it related to the pKa values of an amino acid? c) What practical technique would you use to separate a mixture of the amino acids arginine, valine and glutamic acid? State briefly how it works. d) Describe in detail the two analytical methods that can be used to separate a complex mixture of proteins, yielding individual proteins with different amino acid sequences.

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 22.68P

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