Contacts of the helix formed by residues 63 - 93 (chain A) in PDB entry 1J5N


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 THR 63 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     59A  TRP      4.4     1.2    +      -       -      -
     60A  LYS*     3.8    10.0    +      -       -      +
     61A  ALA      3.6     3.6    +      -       -      -
     62A  LEU*     1.3    91.0    +      -       -      +
     64A  PRO*     1.3    85.8    -      -       +      +
     65A  GLU*     3.6    17.0    -      -       +      +
     66A  GLU*     2.7    27.2    +      -       -      +
     67A  LYS*     3.0    14.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with PRO 64 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     60A  LYS      5.6     1.3    -      -       -      +
     63A  THR*     1.3    91.6    -      -       +      +
     65A  GLU*     1.3    61.3    +      -       -      +
     67A  LYS*     2.9    41.0    +      -       +      +
     68A  GLN*     3.0    13.1    +      -       -      +
     71A  GLU*     3.9     5.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 65 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     63A  THR*     3.1    10.2    -      -       +      +
     64A  PRO*     1.3    82.4    -      -       -      +
     66A  GLU*     1.3    73.4    +      -       -      +
     68A  GLN*     2.8    48.1    +      -       +      +
     69A  PRO*     3.4     2.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 66 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     62A  LEU*     3.1    59.5    -      -       +      +
     63A  THR*     2.7    15.3    +      -       -      +
     65A  GLU*     1.3    88.2    -      -       -      +
     67A  LYS*     1.3    49.1    +      -       -      -
     69A  PRO*     3.0    12.6    -      -       -      +
     70A  TYR*     2.7    31.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 67 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     59A  TRP*     3.4    48.1    -      -       +      +
     60A  LYS*     5.4     6.2    -      -       +      +
     62A  LEU*     5.2     0.2    -      -       +      -
     63A  THR      3.1    18.6    -      -       -      +
     64A  PRO*     2.9    25.0    +      -       +      +
     66A  GLU*     1.3    75.5    -      -       +      +
     68A  GLN*     1.3    66.0    +      -       -      +
     69A  PRO*     3.0     4.3    -      -       -      -
     70A  TYR*     2.7    13.4    +      -       -      -
     71A  GLU*     2.7    57.9    +      -       +      +
    123C    A      5.2     8.7    +      -       -      -
    124C    T      4.5     6.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLN 68 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     64A  PRO      3.0     8.9    +      -       -      +
     65A  GLU*     2.8    45.5    +      -       -      +
     67A  LYS*     1.3    73.8    -      -       -      +
     69A  PRO*     1.3    60.0    -      -       +      +
     71A  GLU*     4.6     3.1    -      -       -      -
     72A  ALA*     2.5    41.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with PRO 69 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     34A  GLU*     6.1     0.9    -      -       -      +
     65A  GLU      3.4     4.0    -      -       -      +
     66A  GLU*     3.0    21.8    -      -       -      +
     67A  LYS      3.0     0.7    -      -       -      -
     68A  GLN*     1.3    97.6    -      -       +      +
     70A  TYR*     1.3    72.7    +      -       +      +
     72A  ALA*     4.1     1.1    -      -       +      +
     73A  LYS*     3.0    28.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 70 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27A  ALA      3.7     4.0    -      -       -      +
     30A  PHE*     3.6    12.1    -      -       +      -
     31A  PHE*     3.2    57.8    -      +       +      +
     34A  GLU*     4.2    21.1    -      -       +      -
     35A  ASN*     4.8     1.0    +      -       -      -
     59A  TRP*     3.2    27.4    -      +       -      -
     62A  LEU*     4.4    10.3    -      -       +      +
     66A  GLU*     2.7    29.2    +      -       -      +
     67A  LYS*     2.7    17.6    +      -       -      -
     69A  PRO*     1.3    80.4    -      -       +      +
     71A  GLU*     1.3    50.7    +      -       -      +
     72A  ALA      3.0     1.6    -      -       -      -
     73A  LYS*     2.4    34.1    +      -       -      +
     74A  ALA*     2.5    16.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 71 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27A  ALA*     3.5    19.3    -      -       +      +
     64A  PRO*     3.9     8.5    -      -       -      +
     67A  LYS*     2.7    59.6    +      -       +      +
     68A  GLN*     4.4     2.3    +      -       -      +
     70A  TYR*     1.3    72.7    -      -       -      +
     72A  ALA*     1.3    53.1    +      -       -      +
     74A  ALA*     2.6    30.2    +      -       +      +
     75A  GLN*     3.2    21.8    +      -       -      +
    124C    T      3.9    21.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 72 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     68A  GLN*     2.5    27.5    +      -       +      +
     69A  PRO*     4.1     1.3    -      -       +      +
     71A  GLU*     1.3    72.0    -      -       -      +
     73A  LYS*     1.3    58.3    +      -       -      +
     74A  ALA      2.9     9.6    +      -       -      -
     75A  GLN*     3.0    30.0    +      -       -      +
     76A  ALA*     3.0    11.9    +      -       -      +
     79A  LYS*     5.6     0.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 73 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30A  PHE*     3.8    29.7    -      -       +      -
     69A  PRO      3.0    20.3    +      -       -      +
     70A  TYR*     2.4    26.9    +      -       -      +
     72A  ALA*     1.3    69.2    -      -       -      +
     74A  ALA*     1.3    54.7    +      -       -      -
     76A  ALA*     3.4    18.0    -      -       +      +
     77A  ASP*     3.0    30.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 74 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24A  ALA*     5.0     0.9    -      -       -      +
     25A  LEU      5.1     2.7    -      -       -      +
     26A  SER*     4.2     0.7    -      -       -      -
     27A  ALA*     3.7    15.0    -      -       +      +
     30A  PHE*     2.9    26.4    -      -       +      -
     70A  TYR      2.5     8.0    +      -       -      +
     71A  GLU*     2.6    22.1    +      -       +      +
     73A  LYS*     1.3    72.1    -      -       -      +
     75A  GLN*     1.3    50.9    +      -       +      +
     76A  ALA      3.1     1.1    -      -       -      -
     77A  ASP*     3.1     3.5    +      -       -      +
     78A  LYS*     2.7    35.9    +      -       -      +
    124C    T      4.8     2.5    -      -       -      +
    125C    C      4.3    15.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 75 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     71A  GLU*     3.5    32.6    +      -       -      +
     72A  ALA*     3.0    18.8    +      -       -      +
     74A  ALA*     1.3    76.4    -      -       -      +
     76A  ALA*     1.3    58.8    +      -       -      +
     78A  LYS*     3.2    10.8    -      -       -      +
     79A  LYS*     3.0    47.4    +      -       -      +
    125C    C      4.7    15.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 76 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     72A  ALA      3.0    11.3    +      -       -      +
     73A  LYS*     3.4    25.6    -      -       +      +
     75A  GLN*     1.3    79.3    -      -       -      +
     77A  ASP*     1.3    57.6    +      -       -      +
     79A  LYS*     3.4    15.0    +      -       -      +
     80A  ARG*     3.1    23.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 77 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24A  ALA*     2.9    19.3    -      -       -      +
     25A  LEU*     3.0    41.1    +      -       -      +
     30A  PHE*     3.4    29.0    -      -       +      -
     73A  LYS*     3.0    13.3    +      -       -      +
     74A  ALA      3.1     0.4    +      -       -      +
     76A  ALA*     1.3    73.5    -      -       -      +
     78A  LYS*     1.3    65.2    +      -       -      +
     80A  ARG*     3.1    29.3    -      -       -      +
     81A  TYR*     3.2     4.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 78 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24A  ALA*     3.3    13.2    -      -       +      +
     74A  ALA      2.7    14.3    +      -       -      +
     75A  GLN*     3.2    16.8    -      -       +      +
     77A  ASP*     1.3    76.0    -      -       -      +
     79A  LYS*     1.3    62.5    +      -       -      +
     81A  TYR*     3.2    10.7    -      -       +      -
     82A  GLU*     2.9    57.6    +      -       -      +
     85A  LYS*     4.4     3.8    -      -       -      +
    125C    C      3.2    20.6    -      -       -      +
    126C    A      2.5    59.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 79 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75A  GLN*     3.0    41.0    +      -       -      +
     76A  ALA*     3.8    10.6    -      -       -      +
     78A  LYS*     1.3    78.5    -      -       +      +
     80A  ARG*     1.3    62.6    +      -       -      +
     82A  GLU*     2.6    47.0    +      -       +      +
     83A  SER*     3.0    10.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 80 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     76A  ALA      3.1     9.1    +      -       -      +
     77A  ASP*     3.1    32.8    -      -       -      +
     79A  LYS*     1.3    77.0    -      -       -      +
     81A  TYR*     1.3    63.8    +      -       +      +
     83A  SER*     2.9    29.5    +      -       -      -
     84A  GLU*     4.0     9.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 81 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     21A  PRO*     3.3    25.7    -      -       +      +
     23A  ARG*     2.5    63.9    +      -       -      +
     24A  ALA*     4.1     2.9    -      -       +      -
     77A  ASP*     3.2     6.9    +      -       -      +
     78A  LYS*     3.2    12.6    -      -       -      +
     79A  LYS      3.2     0.4    -      -       -      -
     80A  ARG*     1.3    77.5    -      -       +      +
     82A  GLU*     1.3    70.0    +      -       -      +
     83A  SER      2.6     7.1    +      -       -      -
     84A  GLU*     2.6    57.8    +      -       -      +
     85A  LYS*     2.9    33.9    +      -       +      +
    126C    A      3.3    39.3    +      -       -      -
    127C    C      3.8    11.6    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 82 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     78A  LYS*     2.9    25.1    +      -       -      +
     79A  LYS*     2.6    33.4    +      -       -      +
     81A  TYR*     1.3    84.2    -      -       -      +
     83A  SER*     1.3    57.5    +      -       -      -
     85A  LYS*     3.1    27.6    -      -       -      +
     86A  GLU*     3.0    37.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with SER 83 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     79A  LYS      3.0     7.2    +      -       -      -
     80A  ARG*     2.9    33.1    +      -       -      -
     81A  TYR      2.6     4.8    +      -       -      -
     82A  GLU*     1.3    74.3    +      -       -      +
     84A  GLU*     1.3    60.6    +      -       -      -
     85A  LYS      3.0     4.0    -      -       -      -
     86A  GLU*     2.9    34.6    -      -       -      +
     87A  LEU*     3.1     8.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 84 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19A  ASN*     5.1     1.2    -      -       -      +
     21A  PRO*     2.7    43.9    -      -       +      +
     23A  ARG      3.6     1.7    -      -       -      +
     80A  ARG*     4.0    11.9    +      -       -      +
     81A  TYR*     2.6    53.1    +      -       -      +
     83A  SER*     1.3    75.0    -      -       -      +
     85A  LYS*     1.3    54.0    +      -       -      -
     87A  LEU*     3.4    15.1    -      -       +      +
     88A  TYR*     2.9    27.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 85 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     21A  PRO*     3.8     5.6    -      -       +      -
     78A  LYS*     4.4     2.2    -      -       -      +
     81A  TYR*     2.9    40.4    +      -       +      +
     82A  GLU*     3.1    30.5    -      -       -      +
     84A  GLU*     1.3    76.9    -      -       -      +
     86A  GLU*     1.3    74.5    +      -       -      +
     87A  LEU      3.0     1.3    -      -       -      -
     88A  TYR*     2.9    26.9    +      -       +      +
     89A  ASN*     3.0    13.4    +      -       -      +
    126C    A      2.8    28.6    +      -       -      +
    127C    C      2.9    29.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 86 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     82A  GLU*     3.0    17.9    +      -       +      +
     83A  SER*     2.9    35.3    -      -       -      +
     85A  LYS*     1.3    86.9    -      -       +      +
     87A  LEU*     1.3    58.8    +      -       +      +
     89A  ASN*     2.7    24.9    +      -       -      +
     90A  ALA*     3.0    17.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 87 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19A  ASN*     4.9     6.7    -      -       +      -
     83A  SER      3.1     9.1    +      -       -      +
     84A  GLU*     3.4    19.3    -      -       +      +
     85A  LYS      3.0     0.4    -      -       -      -
     86A  GLU*     1.3    82.0    -      -       +      +
     88A  TYR*     1.3    76.2    +      -       -      +
     89A  ASN      2.9     2.2    -      -       -      -
     90A  ALA*     2.5    30.7    +      -       +      +
     91A  THR*     2.6    35.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 88 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     17A  ASP*     2.5    36.4    +      -       -      -
     18A  PRO*     3.1    22.8    -      -       +      +
     19A  ASN*     2.3    47.6    -      -       +      +
     20A  ALA      3.2    15.9    -      -       -      -
     21A  PRO*     3.2    23.1    -      -       +      -
     84A  GLU      2.9    21.0    +      -       -      +
     85A  LYS*     3.0    18.2    -      -       +      +
     87A  LEU*     1.3    74.7    -      -       -      +
     89A  ASN*     1.3    55.6    +      -       +      -
     92A  LEU*     2.6    49.1    +      -       +      +
    127C    C      5.3     9.6    -      -       -      -
    128C    C      4.5    15.9    -      -       -      -
----------------------------------------------------------
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Residues in contact with ASN 89 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     85A  LYS*     3.0    20.8    +      -       -      +
     86A  GLU*     2.7    26.6    +      -       -      +
     87A  LEU      2.7     2.6    +      -       -      -
     88A  TYR*     1.3    80.3    -      -       +      +
     90A  ALA*     1.3    61.4    +      -       -      +
     91A  THR      3.0     9.2    +      -       -      -
     92A  LEU*     3.9    10.1    -      -       +      -
     93A  ALA*     2.5    37.8    +      -       +      +
    127C    C      5.8     0.6    +      -       -      -
    128C    C      5.7     3.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 90 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     86A  GLU*     3.0    19.7    +      -       +      +
     87A  LEU*     2.5    17.9    +      -       +      +
     89A  ASN*     1.3    79.8    +      -       -      +
     91A  THR*     1.3    55.8    +      -       -      +
     93A  ALA*     4.6     3.8    -      -       -      -
----------------------------------------------------------
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Residues in contact with THR 91 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19A  ASN*     2.7    34.1    -      -       -      +
     87A  LEU*     2.6    40.2    +      -       +      +
     89A  ASN      3.0     1.0    -      -       -      -
     90A  ALA*     1.3    76.2    +      -       -      +
     92A  LEU*     1.3    63.6    +      -       -      +
     93A  ALA*     3.3     3.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 92 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     18A  PRO*     2.9    44.4    -      -       +      +
     19A  ASN*     3.1     6.1    -      -       -      +
     88A  TYR*     2.6    55.3    +      -       +      +
     89A  ASN*     3.9     5.2    -      -       +      -
     91A  THR*     1.3    82.3    -      -       -      +
     93A  ALA*     1.3    76.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 93 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     89A  ASN*     2.5    27.7    +      -       +      +
     90A  ALA*     4.6     2.8    -      -       -      -
     91A  THR      3.3     4.7    +      -       -      +
     92A  LEU*     1.3    99.7    -      -       +      +
----------------------------------------------------------
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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