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Structure and Property of the Naturally-Occurring Amino Acids

  • Page ID
    4687
  • [ "article:topic", "authorname:jjakubowskih", "license:ccbyncsa" ]

    Amino Acid 3 Letter Code 1 Letter Code Structure pKa1
    (
    α-carboxyl)
    pka2 (α-amino) pka3 (side chain)

    Nonpolar Side Chains

    Glycine Gly G 2.35 9.78 .
    Alanine Ala A 2.35 9.87 .
    Valine Val V 2.29 9.74 .
    Leucine Leu L 2.33 9.74 .
    Isoleucine Ile I 2.32 9.76 .
    Methionine Met M 2.13 9.28 .
    Proline Pro P 1.95 10.64 .
    Phenylalanine Phe F 2.20 9.31 .
    Tryptophan Trp W 2.46 9.41 .

    Uncharged Polar Side Chains

    Serine Ser S 2.19 9.21 .
    Threonine Thr T 2.09 9.10 .
    Asparagine Asn N 2.14 8.72 .
    Glutamine Gln Q 2.17 9.13 .
    Tyrosine Tyr Y 2.20 9.21 10.46
    Cysteine Cys C 1.92 10.70 8.37

    Charged Polar Side Chains10.54

    Lysine Lys K 2.16 9.06 10.54
    Arginine Arg R 1.82 8.99 12.48
    Histidine His H 1.80 9.33 6.04
    Aspartic Acid Asp D 1.99 9.90 3.90
    Glutamic Acid Glu E 2.10 9.47 4.07