Structure and Functions of AA and Proteins

Question 1

name the nonpolar (only carbons and hydrogens), aliphatic side chains

Answer 1

• Glycine
• Alanine
• Proline

Question 2

name the nonpolar, aliphatic side chains that are branched

Answer 2

• Valine
• Leucine
• Isoleucine

Question 3

name the aromatic side chains

Answer 3

• Phenylalanine
• Tyrosine
• Tryptophan (absorbs UV light)

Question 4

name the 2 sulfur containing AA

Answer 4

• Methionine (nonpolar)
• Cysteine (uncharged polar)

Question 5

name the polar uncharged AA

Answer 5

• Asparagine (amine group on side)
• Glutamine (amine group on side)
• Serine (contain a hydroxyl group)
• Threonine (contain a hydroxyl group, also tyrosine)

Question 6

define zwitterion

Answer 6

• an AA having separate positively and negatively charged groups.

Question 7

name the basic (positive side chains) AA

Answer 7

• Histidine
• Lysine
• Arginine

Question 8

describe the synthesis of GABA

Answer 8

• Formed by decarboxylation of the alpha-carboxyl group of glutamate

Question 9

describe the synthesis of histidine

Answer 9

• Decarboxylation of histidine

Question 10

describe the synthesis of serotonin

Answer 10

• Tryptophan is hydroxylated
• Hydroxytryptophahn is decarboxylated to serotonin

Question 11

describe the synthesis of catecholamines

Answer 11

• Catecholamines: dopamin, norepinephrine and epinephrine
• Formed from tyrosine
  
  • Hydroxylated to dihydroxy-phenylalanine (L-DOPA)
• L-DOPA is decarboxylated to dopamine