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PolyAmino Acids

 Amino Acids Reference Chart

Peptide Explorer
 
  Hydrophobic - aliphatic
Hydrophobic - aromatic
Neutral - polar side chains
Acidic
Basic
Unique
Properties of Common Amino Acids
Hydrophobicity Index
 
Hydrophobic - aliphatic
 
Alanine, Ala, A
Isoleucine, Ile, I
Leucine, Leu, L
Valine, Val, V
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Hydrophobic - aromatic
 
Phenylalanine, Phe, F
Tryptophan, Trp, W
Tyrosine, Tyr, Y
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Neutral - polar side chains
 
Asparagine, Asn, N
Cysteine, Cys, C
Glutamine, Gln, Q
Methionine, Met, M
Serine, Ser, S
Threonine, Thr, T
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Acidic
 
Aspartic acid, Asp, D
Glutamic acid, Glu, E
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Basic
 
Arginine, Arg, R
Histidine, His, H
Lysine, Lys, K
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Unique
 
Glycine, Gly, G
Proline, Pro, P
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Properties of Common Amino Acids
 
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Hydrophobicity Index for Common Amino Acids

The hydrophobicity index is a measure of the relative hydrophobicity, or how soluble an amino acid is in water. In a protein, hydrophobic amino acids are likely to be found in the interior, whereas hydrophilic amino acids are likely to be in contact with the aqueous environment.

The values in the table below are normalized so that the most hydrophobic residue is given a value of 100 relative to glycine, which is considered neutral (0 value). The scales were extrapolated to residues which are more hydrophilic than glycine.

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Small
 
Glycine, Gly, G
Alanine, Ala, A
Serine, Ser, S
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Polar
 
Asparagine, Asn, N
Cysteine, Cys, C
Glutamine, Gln, Q
Methionine, Met, M
Serine, Ser, S
Threonine, Thr, T
Aspartic acid, Asp, D
Glutamic acid, Glu, E
Tyrosine, Tyr, Y
Arginine, Arg, R
Histidine, His, H
Lysine, Lys, K
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