Amino Acid Properties

Question 1

Non polar/ hydrophobic amino acids

Answer 1

Glycine, Alanine, Valine, Leucine, Isoleucine, Methionine, Proline

Question 2

Non polar/hydrophobic aromatic amino acids

Answer 2

Phenylalanine, Tryptophan

Question 3

Polar/hydrophillic uncharged amino acids

Answer 3

Serine, Threonine, Cysteine, Asparagine, Glutamine

Question 4

Polar aromatic amino acid

Answer 4

Tyrosine

Question 5

Polar charged amino acids

Answer 5

Negative: Aspartic Acid, Glutamic Acid Positive: Lysine, Arginine, Histidine

Question 6

Nonpolar, non aromatic qualities

Answer 6

Hydrophobic side chains that avoid water and stabilize protein structure by aligning towards the interior of the protein

Question 7

Proline unique quality…

Answer 7

Proline has an R group that links back to its amino group, which causes a ring structure (restricts flexibility, turns and loops of proteins).

Question 8

Ala, Val, Leu, Ile

Answer 8

have alkyl side chains of varying lengths (hydrophobic core of proteins)

Question 9

Met

Answer 9

contains sulfur atom within a thioether group (often involved in initiating protein synthesis)

Question 10

Aromatic Amino Acids Qualities

Answer 10

have aromatic rings in side chain, which can absorb UV light, making them useful in determining protein concentration via spectometry

Question 11

Phe

Answer 11

nonpolar with a benzyl side chain, contributing to hydrophobic core

Question 12

Tyr

Answer 12

polar due to hydroxyl group attached to the benzyl ring. Structure is vital to signaling pathways using tyrosine kinase receptors

Question 13

Trp

Answer 13

largest amino acid with a complex double ring that includes a nitrogen atom, plays an important role in protein-to-protein interactions

Question 14

Polar, uncharged amino acids qualities

Answer 14

have side chains that can form hydrogen bonds with water, making them hydrophillic

Question 15

Ser and Thr

Answer 15

Both contain a hydroxyl groups, which are often involved in phosphorylation

Question 16

Cysteine unique quality…

Answer 16

Cysteine contains a thiol (-SH group) which can form covalent bonds with other cysteines (disulfide bonds, protein stability)

Question 17

Asn and Gln

Answer 17

Contain amide groups that do not gain or lose protons, remaining neutral in charge and often involved in hydrogen bonding

Question 18

Charged Amino Acids qualities

Answer 18

Important for enzymatic activity and for creating electrostatic interactions that help stabilize protein structure

Question 19

Asp and Glu

Answer 19

have carboxyl group in side chain, which loses protons and become negatively charged (involved in active sites in enzymes)

Question 20

Lys

Answer 20

This amino acid has a terminal primary amino group, often involved in binding to negatively charged molecules

Question 21

Arg

Answer 21

contains guanidinium making it highly basic and often involved in protein binding

Question 22

His

Answer 22

contains imidazole ring which can shuttle protons, playing a crucial role in enzyme active sites and buffering

Question 23

Essential amino acids

Answer 23

Cannot be synthesized by body, obtained from diet: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine

Question 24

Nonessential amino acids

Answer 24

Can be synthesized in the human body: alanine, asparagine, glutamic acid, serine, arginine, cysteine, glutamine, glycine, proline, tyrosine

Question 25

Phosphorylation

Answer 25

addition of phosphate groups (Ser, Thr, Tyr), signaling pathways

Question 26

Glycosylation

Answer 26

addition of carbohydrate group (affects protein folding, stability, cell recognition)

Question 27

acetylation/methylation

Answer 27

in lysine residues, impacts gene expression and protein function

Question 28

Ubiquitination

Answer 28

attachment of ubiquitin to lysine residues, tagging proteins for degradation