Amino Acids Amino Acids Amino Acids Amino Acids

Amino Acids

Amino Acids

Amino Acids

Amino Acids

Properties of Amino Acids • Ques. 4: Use the above structures to answer the questions below: • a. Which amino acid is most polar? • b. Which amino acid is least polar? • c. Which amino acid has an acidic side chain? • d. Which amino acid has a basic side chain?

Properties of Amino Acids • • • Ques. 5: Use the below structures to answer the questions: a. Which amino acid is most polar? b. Which amino acid is least polar? c. Which amino acid is the most polar looking at thr and ser? d. Which amino acid is the least polar looking at asp and glu?

Amino Acids • Zwitterion - acid and amine react with each other internally.

Amino Acids • -> -> Increasing p. H -> -> • p. H << p. K << p. H • Acids: HA molecular A- ionic • Bases: BH+ ionic B molecular

Amino Acids • -> -> Increasing p. H -> -> • p. H << p. K << p. H • Acids: HA molecular A- ionic • Bases: BH+ ionic B molecular

Amino Acids • -> -> Increasing p. H -> -> • p. H << p. K << p. H • Acids: HA molecular A- ionic • Bases: BH+ ionic B molecular

Amino Acids

Separations of Amino Acids

Amino Acids • • • -> -> Increasing p. H -> -> p. H << p. K << p. H Acids: HA molecular A- ionic Bases: BH+ ionic B molecular Mixture of val p. I = 6; asp p. I = 2. 8, lys p. I = 9. 7 in a buffer at p. H = 6. What is the form of each?

Reactions Amino Acids - Salt Formation • Acid + amine --> salt (acid donates H+ to amine)

Reactions Amino Acids - Disulfide • 2 thiols + (O) --> disulfide + HOH

Synthesis of a peptide • Amine + acid --> amide + HOH

Synthesis of a peptide • Amine + acid --> amide + HOH

Synthesis of a peptide • Write repeating units of backbone and add side chains