Amino Acid Browser

Alanine Ala    A
Cysteine Cys    C
Aspartic Acid Asp    D
Glutamic Acid Glu    E
Phenylalanine Phe    F
Glycine Gly    G
Histidine His    H
Isoleucine Ile    I
Lysine Lys    K
Leucine Leu    L
Methionine Met    M
Asparagine Asn    N
Proline Pro    P
Glutamine Gln    Q
Arginine Arg    R
Serine Ser    S
Threonine Thr    T
Valine Val    V
Tryptophan Trp    W
Tyrosine Tyr    Y
Positively charged R group
- Essential in mammals
Codon Sequences:
AAA AAG
Lysine image
C6H14N2O2
Mass Peptide
mass
Monoisotopic
mass
Occurence
in Protein
(%)
pKa 1
(-COOH)
pKa 2
(-NH3)
pKa R
(Side Chain)
pI Hydropathy
Index*
Hydrophobicity
Designation**
146.19 128.17 128.09 5.9 2.2 9.2 11.0
+/- 0.1
9.74 -3.9 W

For the designation of atoms, IUPAC recommends the substitution of Greek letters by the equivalent uppercase Roman letters.

*A scale combining hydrophobicity and hydrophilicity of R groups; negative numbers tend to be hydrophilic, positive numbers tend to be hydrophobic.
**Hydrophobic = L, Hydrophilic = W, Neutral = N
André I, Linse S, Mulder FA. J Am Chem Soc. 2007 Dec 26;129(51):15805-13. Epub 2007 Nov 29.
References for information in the above tables and figures.