16: Amino Acids, Proteins, and Enzymes serine? 16.5 Draw the structure for each of the following amino acids at physiological pH: a. glycine b. T c. glutamate d. Phe 16.6 Draw the structure for each of the following amino acids at physiological pH: a. lysine b. proline c. V d. Tyr 16.7 Classify each of the amino acids in problem 16.5 as polar or nonpolar. If polar, indicate if the R group is neutral, acidic, or basic. Indicate if each is hydrophobic or hydrophilic. 16.8 Classify each of the amino acids in problem 16.6 as polar or nonpolar. If polar, indicate if the R group is neutral, acidic, or basic. Indicate if each is hydrophobic or hydrophilic. 16.9 Give the name for the amino acid represented by each of the following abbreviations: a. Ala b. Q c. K 552 口

Name each peptide using both the one-letter and the three-letter abbreviations for the names of the component amino acids.

The isoelectric point (p) of the following amino acid is determined to be 5.97. H2N. OH Which of the following is the dominant form at pH 6.5? Select one: H2N. OH H,N H,N 10

4. How is the following amino acid classified? H3Ñ-CHC-o CH2 a. nonpolar b. polar neutral c. polar acidic d. polar basic

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Choose from A-F. Two of this amino acid can react with each other (anoxidation reaction) and form a covalent bond. CO- COO COO H3N-C-H H,N-C-H CH2 H2N CH 2 Н-С—он CH2 H2C CH2 CH3 CH3 Choice "A" Choice "B" Choice "C" Coo H,N-C-H H,N-C-H H3N-C-H CH2 CH2 C=CH NH CH2 C-NH | CH SH C-N H Choice "E" Choice "F" Choice "D"

acids Identify which of the following are a-amino acids. CH₁ H₂N-C-COOH a. CH₁ H b. H₂N-C-CH₂-COOH 1 CH, H c. H₂N-CH₂-C-COOH H 1 d. H₂N-C-COOH CH₂CH,

Tetrapeptide example: C-A-F-E. 1. What is the structure of the tetrapeptide at pH 1.3. What is its charge at this point?  2. What is the structure of the tetrapeptide at pH 8.2. What is its charge at this point? 3. What is the structure of the tetrapeptide with 0 net charge. What is its isoelectric point?

is the amino acid above, acidic, basic or neutral?

Choose from A-F. Two of this amino acid can react with each other (anoxidation reaction) and form a covalent bond. COO CO0 H3 N-C-H H3N-C-H CH2 H2N CH 2 H-C-OH CH2 H2C CH2 CH3 CH3 Choice "A" Choice "B" Choice "C" COO- Co0 COO H,N-C-H H3N-C-H CH2 CH2 CH2 C=CH C-NH NH SH CH Choice "D" Choice "E" Choice "F"