A-4
H
C
H
H
3
N
+
C
O
O
H
C
CH
3
H
3
N
+
C
O
O
H
C
CH
H
3
N
+
C
O
O
CH
3
CH
3
H
C
CH
2
H
3
N
+
C
O
O
CH
CH
3
CH
3
H
C
CH
H
3
N
+
C
O
O
CH
2
H
3
C
CH
3
Glycine (Gly)
Nonpolar
Alanine (Ala)
Valine (Val)
Leucine (Leu)
Isoleucine (Ile)
H
C
CH
2
H
3
N
+
C
O
O
CH
2
S
CH
3
H
C
CH
2
H
3
N
+
C
O
O
H
C
CH
2
H
3
N
+
C
O
O
NH
H
C
CH
2
H
2
N
+
C
O
O
H
2
C
CH
2
Methionine (Met)
Phenylalanine (Phe)
Tryptophan (Trp)
Proline (Pro)
Polar
H
C
CH
2
H
3
N
+
C
O
O
OH
H
C
HCOH
H
3
N
+
C
O
O
CH
3
H
C
CH
2
H
3
N
+
C
O
O
SH
H
C
CH
2
H
3
N
+
C
O
O
OH
H
C
CH
2
H
3
N
+
C
O
O
C
NH
2
O
H
C
CH
2
H
3
N
+
C
O
O
C
NH
2
O
CH
2
Serine (Ser)
Threonine (Thr)
Cysteine (Cys)
Tyrosine (Tyr)
Asparagine (Asn)
Glutamine (Gln)
Electrically
charged
Acidic
H
C
CH
2
H
3
N
+
C
O
O
C
O
O
H
C
CH
2
H
3
N
+
C
O
O
C
O
O
CH
2
H
C
CH
2
H
3
N
+
C
O
O
CH
2
CH
2
CH
2
NH
3
+
H
C
CH
2
H
3
N
+
C
O
O
CH
2
CH
2
NH
C
NH
2
+
NH
2
H
C
CH
2
H
3
N
+
C
O
O
NH
NH
+
Aspartic acid (Asp)
Glutamic acid (Glu)
Lysine (Lys)
Arginine (Arg)
Histidine (His)
Basic
The Amino Acids
Appendix C
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