Chapter 1 - Amino Acids, Peptides, and Proteins Flashcards
1
Q
Structure of an amino acid
A
- carboxyl group, amino group (NH2), a hydrogen, and an R group, all attached to an alpha carbon
2
Q
Which amino acid is achiral?
A
- Glycine (R group is an H)
3
Q
What is the one chiral amino acid that is in R configuration instead of S?
A
- Cysteine (R group is a CH2SH group and takes priority over carboxyl group)
4
Q
Alanine R-group
A
- 1 Carbon
- A (Ala)
5
Q
Valine R-group
A
- 2 Carbons
- V (Val)
6
Q
Leucine R-group
A
- 3 Carbons
- L (Leu)
7
Q
Isoleucine R-group
A
- 4 Carbons
- I (Ile)
8
Q
Methionine R-group
A
- 2 Carbons, S, then another Carbon
- M (Met)
9
Q
Proline R-group
A
- forms cyclic amino acid
- nitrogen becomes part of a 5-membered ring ( 3 Carbons in R-group)
- P (Pro)
10
Q
Tryptophan R-group
A
- double ring system including another nitrogen
- W (Trp)
11
Q
Phenylalanine R-group
A
- benzyl group (benzene ring + CH2 group)
- F (Phe)
12
Q
Tyrosine R-group
A
- benzyl group (benzene ring + CH2 group) + Hydroxyl group off the ring
- Y (Tyr)
13
Q
Serine R-group
A
- two carbons + hydroxyl group
- hydroxyl group is on tertiary carbon
- S (Ser)
14
Q
Threonine R-group
A
- two carbons + hydroxyl group
- hydroxyl group is on first carbon of R group
- T (Thr)
15
Q
Asparagine R-group
A
- amide group and 1 carbon
- N (Asn)
