Contacts of the helix formed by residues 2 - 32 (chain A) in PDB entry 1UCU


Residue contacts within the protein are derived with the CSU software (Sobolev V., Sorokine A., Prilusky J., Abola E.E. and Edelman M. (1999) Automated analysis of interatomic contacts in proteins. Bioinformatics, 15, 327-332). A short description of the analytical approach is given at the end of the page.
For CSU analysis of other PDB entry

Note:
Non-standard 3 letter residue codes indicate a heterogroup. To identify and analyse, use LPC software

Legend:
Dist - nearest distance (Å) between atoms of two residues
Surf - contact surface area (Å2) between two residues
HB   - hydrophilic-hydrophilic contact (hydrogen bond)
Arom - aromatic-aromatic contact
Phob - hydrophobic-hydrophobic contact
DC   - hydrophobic-hydrophilic contact (destabilizing contact)
+/-  - indicates presence/absence of a specific contacts
*    - indicates residues forming contacts  by their side chain
       (including CA atoms)
Residues in contact with GLN 2 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      1A  ALA*     1.3    70.3    -      -       -      +
      3A  VAL*     1.3    54.1    +      -       +      +
      4A  ILE      3.1     2.9    -      -       -      -
      5A  ASN*     2.9    24.6    +      -       +      +
      6A  THR*     2.8    50.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 3 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      1A  ALA*     3.0    22.0    -      -       +      +
      2A  GLN*     1.3    78.7    +      -       +      +
      4A  ILE*     1.3    55.0    +      -       -      +
      6A  THR*     3.4    17.3    -      -       +      -
      7A  ASN*     2.7    51.5    +      -       +      +
    490A  LEU*     4.6     7.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 4 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      1A  ALA      3.4    18.6    +      -       -      +
      2A  GLN*     5.3     0.2    -      -       -      -
      3A  VAL*     1.3    73.3    -      -       -      +
      5A  ASN*     1.3    76.8    +      -       -      +
      7A  ASN*     3.9     1.9    -      -       -      +
      8A  SER*     3.0    25.3    +      -       -      -
    490A  LEU*     4.2    37.3    -      -       +      +
    493A  LEU*     6.4     0.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASN 5 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      2A  GLN*     2.9    26.2    +      -       +      +
      4A  ILE*     1.3    93.3    -      -       -      +
      6A  THR*     1.3    64.9    +      -       -      +
      7A  ASN      3.1     1.8    -      -       -      -
      8A  SER*     3.0    17.2    +      -       -      -
      9A  LEU*     3.0    22.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with THR 6 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      2A  GLN*     2.8    28.3    +      -       -      +
      3A  VAL*     3.4    32.1    -      -       +      +
      5A  ASN*     1.3    73.1    -      -       -      +
      7A  ASN*     1.3    62.9    +      -       -      +
      9A  LEU*     3.0    29.6    -      -       -      +
     10A  SER*     3.1     6.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with ASN 7 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      3A  VAL*     2.7    33.3    +      -       +      +
      4A  ILE      3.9     1.1    -      -       -      +
      6A  THR*     1.3    70.6    -      -       -      +
      8A  SER*     1.3    53.8    +      -       -      +
      9A  LEU      2.9     2.0    -      -       -      -
     10A  SER*     2.7    15.5    +      -       -      -
     11A  LEU*     2.6    67.5    +      -       -      +
    486A  PRO*     3.4    14.1    -      -       -      +
    489A  VAL*     5.4     7.3    -      -       -      +
    490A  LEU*     3.4    26.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with SER 8 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      4A  ILE      3.0    16.7    +      -       -      -
      5A  ASN*     3.0    17.9    +      -       -      -
      7A  ASN*     1.3    76.7    -      -       -      +
      9A  LEU*     1.3    52.0    +      -       -      +
     11A  LEU*     3.1    18.0    +      -       -      +
     12A  LEU*     2.6    33.3    +      -       -      +
     15A  ASN*     5.3     0.5    +      -       -      -
    490A  LEU*     6.2     0.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 9 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      5A  ASN*     3.0    27.7    +      -       +      +
      6A  THR*     3.0    17.9    -      -       -      +
      7A  ASN      2.9     0.4    -      -       -      -
      8A  SER*     1.3    77.5    -      -       -      +
     10A  SER*     1.3    54.9    +      -       -      +
     11A  LEU      2.9     5.4    -      -       -      -
     12A  LEU*     2.9    43.0    +      -       +      +
     13A  THR*     3.0    19.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with SER 10 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      6A  THR      3.1     5.5    +      -       -      -
      7A  ASN*     2.7    24.6    +      -       -      -
      9A  LEU*     1.3    76.6    -      -       -      +
     11A  LEU*     1.3    60.8    +      -       -      +
     13A  THR*     2.6    23.3    +      -       -      -
     14A  GLN*     3.2    19.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 11 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      7A  ASN*     2.6    41.5    +      -       -      +
      8A  SER*     3.3    14.1    -      -       -      +
      9A  LEU      2.9     0.2    -      -       -      -
     10A  SER*     1.3    81.6    -      -       -      +
     12A  LEU*     1.3    53.9    +      -       -      +
     13A  THR      3.1     1.8    -      -       -      -
     14A  GLN*     3.0    25.3    +      -       -      +
     15A  ASN*     2.6    42.7    +      -       -      +
    483A  ASN      5.5     0.4    -      -       -      +
    486A  PRO*     3.1    33.2    -      -       +      -
    487A  GLN*     4.6    13.0    -      -       +      +
    490A  LEU*     4.5    12.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 12 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      8A  SER      2.6    13.2    +      -       -      +
      9A  LEU*     2.9    33.4    +      -       +      +
     11A  LEU*     1.3    76.4    -      -       -      +
     13A  THR*     1.3    52.7    +      -       +      +
     15A  ASN*     3.2    21.1    +      -       +      +
     16A  ASN*     2.6    43.7    +      -       -      +
     19A  LYS*     5.4     9.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 13 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      9A  LEU*     3.0    14.1    +      -       +      +
     10A  SER*     2.6    31.7    +      -       -      -
     12A  LEU*     1.3    77.1    -      -       +      +
     14A  GLN*     1.3    58.4    +      -       -      +
     16A  ASN*     3.0    29.8    +      -       +      +
     17A  LEU*     3.1    10.6    +      -       -      +
    479A  LEU*     4.2     4.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 14 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     10A  SER*     3.2    20.1    +      -       -      +
     11A  LEU*     3.0    31.7    +      -       -      +
     13A  THR*     1.3    76.9    +      -       -      +
     15A  ASN*     1.3    59.7    +      -       -      +
     16A  ASN      3.1     0.2    -      -       -      -
     17A  LEU*     3.0    22.2    +      -       -      +
     18A  ASN*     3.4     8.0    +      -       -      -
    479A  LEU*     3.4    37.3    -      -       +      +
    482A  ALA*     2.9    39.1    +      -       -      +
    483A  ASN*     4.1     5.2    -      -       +      -
    486A  PRO*     3.6     6.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 15 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      8A  SER      5.3     0.4    +      -       -      -
     11A  LEU*     2.6    30.4    +      -       -      +
     12A  LEU*     3.3    23.5    -      -       +      +
     14A  GLN*     1.3    70.6    -      -       -      +
     16A  ASN*     1.3    60.7    +      -       -      +
     17A  LEU      3.0     1.8    -      -       -      -
     18A  ASN*     2.9    42.3    +      -       +      +
     19A  LYS*     3.1    13.4    +      -       -      +
    483A  ASN*     5.8     2.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with ASN 16 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12A  LEU*     2.6    23.9    +      -       -      +
     13A  THR*     3.0    22.0    +      -       +      +
     15A  ASN*     1.3    76.4    -      -       -      +
     17A  LEU*     1.3    52.7    +      -       -      +
     18A  ASN      3.1     0.7    -      -       -      -
     19A  LYS*     3.0    43.2    +      -       -      +
     20A  SER*     2.7    33.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 17 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     13A  THR      3.1     5.2    +      -       -      +
     14A  GLN      3.0    14.7    +      -       -      +
     15A  ASN      3.0     0.6    -      -       -      -
     16A  ASN*     1.3    78.0    -      -       -      +
     18A  ASN*     1.3    54.1    +      -       -      +
     19A  LYS      3.0     0.4    -      -       -      -
     20A  SER*     3.0    23.0    +      -       -      +
     21A  GLN*     2.6    30.0    +      -       -      +
     24A  LEU*     5.7     0.2    -      -       +      -
    472A  GLN*     4.4     5.4    -      -       +      +
    475A  GLY*     3.8     6.3    -      -       -      +
    476A  THR*     3.5    37.9    +      -       -      +
    479A  LEU*     3.4    36.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASN 18 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     14A  GLN      3.4     4.0    +      -       -      -
     15A  ASN*     2.9    40.9    +      -       +      +
     17A  LEU*     1.3    78.3    -      -       -      +
     19A  LYS*     1.3    58.3    +      -       +      +
     21A  GLN*     3.0    33.7    +      -       -      +
     22A  SER*     2.9    21.8    +      -       -      -
    476A  THR*     5.2     1.1    +      -       -      -
    483A  ASN*     6.2     0.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 19 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12A  LEU*     5.4    10.2    -      -       -      +
     15A  ASN*     3.1    11.6    +      -       -      +
     16A  ASN*     3.0    47.0    +      -       -      +
     18A  ASN*     1.3    77.4    -      -       +      +
     20A  SER*     1.3    53.3    +      -       -      +
     21A  GLN      3.0     5.6    -      -       -      -
     22A  SER*     3.1    13.6    +      -       -      -
     23A  ALA*     2.9    21.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 20 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     16A  ASN      2.7    17.8    +      -       -      -
     17A  LEU*     3.0    36.1    +      -       -      +
     19A  LYS*     1.3    73.8    -      -       -      +
     21A  GLN*     1.3    55.0    +      -       -      +
     22A  SER      3.2     0.7    -      -       -      -
     23A  ALA*     3.1    15.1    +      -       -      +
     24A  LEU*     2.8    33.0    +      -       -      +
    472A  GLN*     4.2     9.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 21 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     17A  LEU      2.6    11.7    +      -       -      +
     18A  ASN*     3.0    35.5    +      -       -      +
     20A  SER*     1.3    74.2    -      -       -      +
     22A  SER*     1.3    55.9    +      -       -      +
     23A  ALA      3.0     1.3    -      -       -      -
     24A  LEU*     3.0    23.6    +      -       +      +
     25A  GLY*     2.8    28.9    +      -       -      -
    476A  THR*     3.8    17.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with SER 22 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     18A  ASN      2.9    10.7    +      -       -      -
     19A  LYS*     3.1    20.4    -      -       -      -
     21A  GLN*     1.3    79.5    -      -       -      +
     23A  ALA*     1.3    48.6    +      -       -      -
     25A  GLY*     3.4     2.8    +      -       -      +
     26A  THR*     2.7    34.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 23 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19A  LYS      2.9     7.4    +      -       -      +
     20A  SER*     3.1    22.7    -      -       -      +
     21A  GLN      3.0     0.2    -      -       -      -
     22A  SER*     1.3    77.3    -      -       -      +
     24A  LEU*     1.3    53.1    +      -       -      +
     26A  THR*     3.3    15.0    -      -       +      +
     27A  ALA*     2.6    34.8    +      -       -      +
    472A  GLN*     4.2    13.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 24 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     17A  LEU*     5.7     0.4    -      -       +      -
     20A  SER      2.8    15.7    +      -       -      +
     21A  GLN*     3.0    27.5    +      -       +      +
     23A  ALA*     1.3    75.2    -      -       -      +
     25A  GLY*     1.3    53.2    +      -       -      +
     27A  ALA*     3.3     7.2    +      -       +      +
     28A  ILE*     2.8    36.2    +      -       -      +
    469A  GLN*     3.3    38.0    -      -       +      +
    472A  GLN*     3.4    25.4    -      -       +      +
    473A  GLN*     3.8    21.3    -      -       +      +
    476A  THR*     4.0    24.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 25 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     21A  GLN      2.8    13.7    +      -       -      -
     22A  SER*     3.6     4.7    -      -       -      -
     24A  LEU*     1.3    77.8    -      -       -      +
     26A  THR*     1.3    52.4    +      -       -      +
     28A  ILE*     3.2    15.1    +      -       -      +
     29A  GLU*     2.7    32.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 26 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     22A  SER*     2.7    21.1    +      -       -      -
     23A  ALA*     3.2    17.7    +      -       +      +
     25A  GLY*     1.3    70.6    -      -       -      +
     27A  ALA*     1.3    59.3    +      -       +      +
     29A  GLU*     3.2    10.6    +      -       -      +
     30A  ARG*     2.8    72.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 27 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     23A  ALA      2.6    20.9    +      -       -      +
     24A  LEU*     3.4     9.6    -      -       +      +
     26A  THR*     1.3    72.9    -      -       +      +
     28A  ILE*     1.3    55.4    +      -       -      +
     29A  GLU      3.0     1.1    -      -       -      -
     30A  ARG*     2.9    12.0    +      -       -      +
     31A  LEU*     2.7    52.2    +      -       +      +
    465A  MET*     4.8    14.1    -      -       +      +
    469A  GLN*     4.7     9.0    -      -       +      -
    472A  GLN*     5.0    10.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 28 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24A  LEU      2.8    17.5    +      -       -      +
     25A  GLY*     3.3    15.9    -      -       -      +
     27A  ALA*     1.3    76.4    -      -       -      +
     29A  GLU*     1.3    53.0    +      -       -      +
     31A  LEU*     3.5     8.6    -      -       +      +
     32A  SER*     2.7    36.2    +      -       -      -
    469A  GLN*     3.9    26.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 29 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     25A  GLY      2.7    13.2    +      -       -      +
     26A  THR*     3.2    15.9    -      -       -      +
     27A  ALA      3.0     0.2    -      -       -      -
     28A  ILE*     1.3    77.1    -      -       +      +
     30A  ARG*     1.3    61.5    +      -       +      +
     31A  LEU      3.1     1.6    -      -       -      -
     32A  SER*     3.0    36.1    +      -       -      -
     33A  SER*     3.5     5.7    +      -       -      -
     34A  GLY      4.4     0.3    +      -       -      -
     35A  LEU      5.5     0.2    -      -       -      +
     36A  ARG*     4.3    31.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 30 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     26A  THR*     2.8    49.4    +      -       -      +
     27A  ALA*     3.5     8.9    -      -       -      +
     29A  GLU*     1.3    73.3    -      -       +      +
     31A  LEU*     1.3    59.1    +      -       +      +
     34A  GLY*     2.9    34.5    -      -       -      +
     36A  ARG*     5.5    11.0    -      -       +      -
    457A  ASP*     5.0     4.8    -      -       -      +
    465A  MET*     4.9    20.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 31 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27A  ALA*     2.7    30.5    +      -       +      +
     28A  ILE*     3.5     8.1    -      -       +      +
     30A  ARG*     1.3    79.4    -      -       +      +
     32A  SER*     1.3    64.7    -      -       -      +
     33A  SER      3.4     1.6    +      -       -      -
     34A  GLY*     3.9     6.0    +      -       -      +
    457A  ASP*     3.6    31.3    -      -       +      +
    462A  VAL*     3.5    33.2    -      -       +      -
    465A  MET*     3.8    26.0    -      -       +      +
    469A  GLN*     3.1    34.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with SER 32 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     28A  ILE*     2.7    21.5    +      -       -      -
     29A  GLU*     3.0    26.3    +      -       -      -
     31A  LEU*     1.3    79.6    -      -       -      +
     33A  SER*     1.3    60.6    +      -       -      +
----------------------------------------------------------
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A short description of the analytical approach
The contact analysis used in this page is based upon the approach developed in: Sobolev V., Wade R.C., Vriend G. and Edelman M. PROTEINS (1996) 25, 120-129. Contact legitimacy depends on the hydrophobic-hydrophilic properties of the contacting atoms. In order to define it, for each inter-atomic contact, eight atom classes have been introduced:


   I  Hydrophilic      - N and O that can donate and accept hydrogen bonds
                         (e.g., oxygen of hydroxyl group of Ser. or Thr)
  II  Acceptor         - N or O that can only accept a hydrogen bond
 III  Donor            - N that can only donate a hydrogen bond
  IV  Hydrophobic      - Cl, Br, I and all C atoms that are not in
                         aromatic rings and do not have a covalent bond to
                         a N or O atom
   V  Aromatic         - C in aromatic rings irrespective of any other 
                         bonds formed by the atom
  VI  Neutral          - C atoms that have a covalent bond to at least one
                         atom of class I or two or more atoms from class II
                         or III; atoms; S, F, P, and metal atoms in all cases
 VII  Neutral-donor    - C atoms that have a covalent bond with only one
                         atom of class III
VIII  Neutral-acceptor - C atoms that have a covalent bond with only 
                         one atom of class II
For each pair of contacts the state of legitimacy is shown below:

Legend:
+, legitimate
-, illegitimate
------------------------------------------------------------
  Atomic class           I  II  III   IV   V   VI  VII  VIII
------------------------------------------------------------
   I  (Hydrophilic)      +   +    +    -   +   +    +    +
  II  (Acceptor)         +   -    +    -   +   +    +    -
 III  (Donor)            +   +    -    -   +   +    -    +
  IV  (Hydrophobic)      -   -    -    +   +   +    +    +
   V  (Aromatic)         +   +    +    +   +   +    +    +
  VI  (Neutral)          +   +    +    +   +   +    +    +
 VII  (Neutral-donor)    +   +    -    +   +   +    -    +
VIII  (Neutral-acceptor) +   -    +    +   +   +    +    -
------------------------------------------------------------
Warning!
Atom classes for heterogroups are automatically assigned based on the atomic coordinates. However, in three cases (see below) the automatic assignment is currently ambiguous. In these cases, the user is advised to manually analyse the full list of contacts using LPC software.
1. Carbon atoms belonging to a 4-, 5- or 6-member ring are 
   considered "aromatic" (Class V) if the ring is approximately
   planar, and "hydrophobic" (Class IV) or "neutral" (Classes
   VI, VII, VIII) if the ring is non-planar.
2. The oxygen atom of a carbonyl or hydroxy group is considered
   "hydroxy" (Class I) if the CO bond is longer than 1.29 Å, and
   "carbonyl" (Class II) if shorter.
3. All nitrogen atoms are considered "hydrophilic" (Class I).

Please E-mail any questions and/or suggestions concerning this page to Vladimir.Sobolev@weizmann.ac.il