1) Find the pH of 0.1 M of the differnet forms histidine species. (See image for equation and pKa values)2) What is the principal specis at pH 1, pH 5, pH 8, and pH 11? ### Chemical Structure of Histidine and Its Ionization States**Histidine Structure:**- The image shows the molecular structure of histidine, an essential amino acid.- The structure includes an imidazole ring, which is aromatic and contains two nitrogen atoms.- An amino group (\( \text{-NH}_2 \)), a carboxyl group (\( \text{-COOH} \)), and a side chain are also depicted. **Ionization States of Histidine:**- The image describes the ionization sequence of histidine, showing the removal of protons and the corresponding pKa values.1. **\( \text{H}_3\text{His}^{2+} \rightarrow \text{H}_2\text{His}^{+} \)** - The first dissociation involves the removal of a proton, resulting in a singly charged ion. - \( \text{pK}_\text{a1} = 1.60 \)2. **\( \text{H}_2\text{His}^{+} \rightarrow \text{HHis} \)** - The second dissociation removes another proton, resulting in the neutral form. - \( \text{pK}_\text{a2} = 5.97 \)3. **\( \text{HHis} \rightarrow \text{His}^- \)** - The final dissociation results in a negatively charged histidine ion. - \( \text{pK}_\text{a3} = 9.28 \)These transitions are crucial in understanding the chemical behavior of histidine in different pH environments, which affects its role in biological systems like enzyme active sites and protein structures.

Amino acids are building blocks of the proteins. Alpha carbon of amino acids consist of carboxyl…

Answered: 1) Find the pH of 0.1 M of the…

1) Find the pH of 0.1 M of the differnet forms histidine species. (See image for equation and pKa values) 2) What is the principal specis at pH 1, pH 5, pH 8, and pH 11?

Biochemistry

9th Edition

ISBN:9781319114671

Author:Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.

Publisher:Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.

Chapter1: Biochemistry: An Evolving Science

Section: Chapter Questions

Problem 1P

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