Amino Acids

Question 1

What are the 7 non-polar (hydrophobic) amino acids?

Answer 1

1. Glycine
2. Alanine
3. Valine
4. Leucine
5. Isoleucine
6. phenylalinine
7. Tryptophan

Question 2

Answer 2

Serine

1. Ser/S
2. Polar AA
3. Hydrophillic and interact with water whenever possible
   
   1. Can H-Bond with H2O, but does not act as an acid or base

Question 3

Answer 3

Glysine

1. Gly/G
2. Hydrophobic amino acid
3. Associates with other hydrophobic amino acids (usually in the core of proteins)

Question 4

Answer 4

Valine

1. Val/V
2. Hydrophobic amino acid
3. Associates with other hydrophobic amino acids (usually in the core of proteins)

Question 5

Answer 5

Arginine

1. Arg/R
2. Basic Amino Acid
3. Protonated (Cationic) at physiological pH
4. pKa ~ 12
5. pI above 6

Question 6

Answer 6

Cysteine

1. Cys/C
2. Fairly Polar
3. Forms disulfide Bridges

Question 7

What are the sulfur containing AA?

Answer 7

1. Cysteine
2. Methionine

Question 8

Answer 8

Asparagine

1. Asp/N
2. Polar AA
3. Hydrophillic and interact with water whenever possible
4. Can H-Bond with H2O, but does not act as an acid or base

Question 9

What are the two acidic amino acids? Why are they considered acidic?

Answer 9

1. Aspartic Acid (D)
2. Glutamic Acid (E)
3. These both contain COOH whithin their side chains

Question 10

What are the polar amino acids?

Answer 10

1. Serine
2. Threonine
3. Tyrosine
4. Asparigine
5. Glutamine

Question 11

Answer 11

Alanine

1. Ala/A
2. Hydrophobic amino acid
3. Associates with other hydrophobic amino acids (usually in the core of proteins)

Question 12

Answer 12

Phenylalanine

1. Phe/F
2. Hydrophobic amino acid
3. Associates with other hydrophobic amino acids (usually in the core of proteins)

Question 13

Answer 13

Glutamine

1. Gln/Q
2. Polar AA
3. Hydrophillic and interact with water whenever possible
4. Can H-Bond with H2O, but does not act as an acid or base

Question 14

Answer 14

Methionine

1. Met/M
2. Relatively Non-polar

Question 15

Answer 15

Tyrosine

1. Tyr/Y
2. Polar AA
3. Hydrophillic and interact with water whenever possible
4. Can H-Bond with H2O, but does not act as an acid or base

Question 16

Answer 16

Glutamic Acid

1. Glu/E
2. Acidic Amino Acid
3. Glutamate when deprotonated
4. Deprotonated (anionic) at Physiological pH
5. pKa ~ 4
6. pI below 6

Question 17

Answer 17

Isoleusine

1. Ile/I
2. Hydrophobic amino acid
3. Associates with other hydrophobic amino acids (usually in the core of proteins)

Question 18

Answer 18

Leucine

1. Leu/L
2. Hydrophobic amino acid
3. Associates with other hydrophobic amino acids (usually in the core of proteins)

Question 19

Answer 19

Aspartic Acid (D)

1. Asp/D
2. Acidic Amino Acid
3. Aspartate when deprotonated
4. Deprotonated (anionic) at Physiological pH
5. pKa ~ 4
6. pI below 6

Question 20

Answer 20

Tryptophan

1. Trp/W
2. Hydrophobic amino acid
3. Associates with other hydrophobic amino acids (usually in the core of proteins)

Question 21

Answer 21

Proline

1. Pro/P
2. Side group is covalently bound to amine group
3. Can never be present in alpha helices (because it disrupts hydrogen bonding between carbonyl oxygen and amine hydrogen)
4. When present, causes a “kink” in the polypeptode chain

Question 22

What are the basic amino acids? Why are they considered basic?

Answer 22

1. Lysine
2. Arganine
3. Histadine
4. They all contain amino side chains

Question 23

Answer 23

Histidine

1. His/H
2. Categorized as basic, but can act as a base or acid at physiological pH
3. Protonated (Cationic) or Deprotonated at physiological pH
4. pKa ~ 6.5
5. pI above 6

Question 24

Answer 24

Threonine

1. Thr/T
2. Polar AA
3. Hydrophillic and interact with water whenever possible
4. Can H-Bond with H2O, but does not act as an acid or base

Question 25

Answer 25

Lysine

1. Lys/K
2. Basic Amino Acid
3. Protonated (Cationic) at physiological pH
4. pKa ~ 10
5. pI above 6