At pH 9.5, the charge on the side chain of Arg is +1 Peptide lonization Consider a peptide with the sequence Ser-His-Glu-Cys-Arg-Gln. You will be asked to state the charge on the functional groups of this peptide at pH 1 and pH 9.5. You will also be asked to calculate the net charge on the peptide. You may find it convenient to write down the charge on each group on a piece of paper as you go along, so that you can add them up at the end. Assume the following generic pK, values for ionizable functional groups: a-carboxyl: side-chain carboxyl: imidazole: 3.1 4.1 6.0 a-amino: 8.0 thiol: 8.3 E-amino: 10.8 aromatic hydroxyl: guanidino: 10.9 12.5

At pH 9.5, the charge on the side chain of Arg is +1 Peptide lonization Consider a peptide with the sequence Ser-His-Glu-Cys-Arg-Gln. You will be asked to state the charge on the functional groups of this peptide at pH 1 and pH 9.5. You will also be asked to calculate the net charge on the peptide. You may find it convenient to write down the charge on each group on a piece of paper as you go along, so that you can add them up at the end. Assume the following generic pK, values for ionizable functional groups: a-carboxyl: side-chain carboxyl: imidazole: 3.1 4.1 6.0 a-amino: 8.0 thiol: 8.3 E-amino: 10.8 aromatic hydroxyl: guanidino: 10.9 12.5

Biology 2e

2nd Edition

ISBN:9781947172517

Author:Matthew Douglas, Jung Choi, Mary Ann Clark

Publisher:Matthew Douglas, Jung Choi, Mary Ann Clark

Chapter3: Biological Macromolecules

Section: Chapter Questions

Problem 23CTQ: Amino acids have the generic structure seen below, where R represents different carbon-based side...

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