Contacts of the helix formed by residues 111 - 139 (chain A) in PDB entry 3KCN


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 111 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    109A  PRO      4.0     1.7    +      -       -      +
    110A  CYS*     1.3    72.8    -      -       -      +
    112A  MSE      1.3    67.9    +      -       -      +
    113A  SER*     4.2    11.4    +      -       -      +
    114A  ASP*     3.0    36.4    +      -       -      +
    115A  ILE*     3.1    12.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with MSE 112 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     21A  THR*     5.6     0.9    -      -       -      +
     22A  LEU*     4.3    19.3    -      -       -      -
     25A  ASN*     3.5    40.2    -      -       -      +
     26A  LEU*     3.3    31.4    -      -       +      -
    110A  CYS      3.7     2.6    +      -       -      -
    111A  GLN*     1.3    72.6    +      -       -      +
    113A  SER*     1.3    56.8    +      -       -      +
    115A  ILE*     3.1    23.4    +      -       +      +
    116A  LYS*     2.9    46.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 113 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    111A  GLN*     4.2    10.5    -      -       -      +
    112A  MSE      1.3    78.1    -      -       -      +
    114A  ASP*     1.3    60.8    +      -       -      +
    116A  LYS*     3.5     8.4    +      -       -      +
    117A  ALA*     3.0    30.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 114 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    106A  LEU*     3.7    18.0    -      -       +      +
    110A  CYS*     5.3     1.3    -      -       +      -
    111A  GLN*     3.0    32.0    +      -       -      +
    113A  SER*     1.3    81.9    -      -       -      +
    115A  ILE*     1.3    56.8    +      -       -      +
    117A  ALA*     3.4     6.1    +      -       -      +
    118A  ALA*     3.0    28.1    +      -       -      +
     99B  GLU*     6.2     0.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 115 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     22A  LEU*     3.9    27.8    -      -       +      -
     26A  LEU*     4.6     4.5    -      -       +      -
     55A  MSE      4.2    15.2    -      -       +      +
     84A  LEU*     5.0     9.6    -      -       +      -
    106A  LEU*     4.0    12.1    -      -       +      -
    110A  CYS*     3.9    32.8    -      -       +      +
    111A  GLN      3.5    13.9    -      -       -      +
    112A  MSE      3.1    22.1    +      -       +      +
    114A  ASP*     1.3    73.3    -      -       -      +
    116A  LYS*     1.3    61.0    +      -       -      +
    118A  ALA*     3.2     4.3    +      -       -      +
    119A  ILE*     3.0    45.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 116 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     25A  ASN*     3.6    23.5    +      -       -      +
     26A  LEU*     4.2    15.5    -      -       +      -
     29A  ASP*     4.0    21.7    +      -       -      +
     30A  PHE*     4.4     9.0    -      -       +      -
    112A  MSE      2.9    32.6    +      -       +      +
    113A  SER*     3.8     7.2    -      -       -      +
    115A  ILE*     1.3    74.5    -      -       -      +
    117A  ALA*     1.3    65.3    +      -       -      +
    119A  ILE*     4.0     7.2    -      -       -      +
    120A  ASN*     3.0    42.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 117 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    113A  SER      3.0    17.5    +      -       -      +
    114A  ASP*     3.7     7.4    -      -       -      +
    116A  LYS*     1.3    78.5    -      -       -      +
    118A  ALA*     1.3    56.3    +      -       -      +
    120A  ASN*     3.6     6.5    +      -       -      +
    121A  ALA*     2.9    30.5    +      -       -      +
     99B  GLU*     4.0    25.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 118 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     55A  MSE      6.4     0.2    -      -       -      -
     82A  LEU*     3.7    25.9    -      -       +      +
    103A  PHE*     5.2     1.0    -      -       -      -
    104A  ARG*     4.7    15.7    -      -       +      +
    106A  LEU*     3.8    22.2    -      -       +      -
    114A  ASP      3.0    14.7    +      -       -      +
    115A  ILE      3.2     8.5    +      -       -      +
    117A  ALA*     1.3    75.0    -      -       -      +
    119A  ILE*     1.3    57.0    +      -       -      +
    121A  ALA*     3.3     6.7    +      -       -      +
    122A  GLY*     2.8    26.3    +      -       -      -
     99B  GLU*     5.3     1.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 119 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      9A  ILE*     4.1    20.6    -      -       +      -
     26A  LEU*     3.5    36.6    -      -       +      -
     30A  PHE*     3.6    29.2    -      -       +      -
     53A  VAL*     3.8     9.2    -      -       +      +
     55A  MSE      4.5    11.2    -      -       +      -
     82A  LEU*     4.1    16.2    -      -       +      -
    115A  ILE*     3.0    35.8    +      -       +      +
    116A  LYS*     4.0     4.0    -      -       -      +
    118A  ALA*     1.3    73.8    -      -       -      +
    120A  ASN*     1.3    59.5    +      -       -      +
    122A  GLY*     3.1     2.3    +      -       -      -
    123A  ILE*     2.9    41.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 120 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      7A  GLU*     5.5     1.0    -      -       -      +
     30A  PHE*     3.5    22.5    -      -       -      -
    116A  LYS*     3.0    38.7    +      -       -      +
    117A  ALA*     3.8     6.3    -      -       -      +
    119A  ILE*     1.3    76.1    -      -       -      +
    121A  ALA*     1.3    61.0    +      -       -      +
    123A  ILE*     3.4     8.7    +      -       -      +
    124A  LYS*     3.3    24.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 121 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    103A  PHE*     4.0     4.8    -      -       +      -
    104A  ARG*     3.5    32.1    -      -       -      +
    117A  ALA      2.9    18.1    +      -       -      +
    118A  ALA      3.6     4.9    -      -       -      +
    119A  ILE      3.2     0.4    -      -       -      -
    120A  ASN*     1.3    74.4    -      -       -      +
    122A  GLY*     1.3    58.0    +      -       -      +
    124A  LYS*     3.4    12.8    +      -       -      +
    125A  GLN*     3.0    27.5    +      -       -      +
     99B  GLU*     3.9    11.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 122 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     53A  VAL*     3.5    14.6    -      -       -      -
     80A  VAL*     3.5    29.3    -      -       -      +
     82A  LEU*     5.0     1.3    -      -       -      -
    103A  PHE*     4.2     3.3    -      -       -      -
    118A  ALA      2.8    14.8    +      -       -      -
    119A  ILE      3.1     4.0    +      -       -      -
    121A  ALA*     1.3    76.0    -      -       -      +
    123A  ILE*     1.3    57.5    +      -       -      +
    125A  GLN*     3.3     2.3    +      -       -      -
    126A  TYR*     2.9    25.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 123 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      5A  LEU*     4.1    27.0    -      -       +      +
      6A  ASN      3.6    18.6    -      -       -      +
      7A  GLU*     4.4     9.4    -      -       +      +
      9A  ILE*     4.6     2.5    -      -       +      -
     30A  PHE*     3.5    37.7    -      -       +      -
     52A  SER*     3.7    18.4    -      -       -      +
     53A  VAL*     3.9     7.0    -      -       +      -
    119A  ILE*     2.9    24.5    +      -       +      +
    120A  ASN*     3.8     7.9    -      -       -      +
    121A  ALA      3.4     0.4    -      -       -      -
    122A  GLY*     1.3    75.4    -      -       -      +
    124A  LYS*     1.3    61.3    +      -       -      +
    126A  TYR*     3.4     8.4    +      -       -      +
    127A  ASP*     3.2    20.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 124 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      5A  LEU*     6.0     0.9    -      -       -      -
    120A  ASN      3.3    14.6    +      -       -      +
    121A  ALA*     3.5     9.9    -      -       -      +
    123A  ILE*     1.3    75.8    -      -       -      +
    125A  GLN*     1.3    65.9    +      -       -      +
    127A  ASP*     3.5     8.4    +      -       +      +
    128A  LEU*     3.2    38.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 125 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     80A  VAL*     3.7    16.8    -      -       +      -
    103A  PHE*     3.6    35.2    -      -       +      -
    121A  ALA      3.0    15.0    +      -       -      +
    122A  GLY      3.5     9.4    -      -       -      +
    124A  LYS*     1.3    76.1    -      -       -      +
    126A  TYR*     1.3    61.5    +      -       -      +
    128A  LEU*     3.3    14.8    +      -       -      +
    129A  VAL*     3.2    36.6    +      -       +      +
    103B  PHE*     5.8     0.2    -      -       -      -
    125B  GLN*     3.0    39.7    +      -       -      +
    128B  LEU*     4.1     4.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 126 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      6A  ASN*     3.6    32.1    +      -       +      -
     50A  PRO*     3.6    24.2    -      -       +      +
     51A  PHE      3.8    13.0    -      -       -      -
     52A  SER*     3.5    32.1    -      -       -      +
     78A  ASN*     3.5    41.5    +      -       +      +
     79A  SER      4.0     0.4    -      -       -      -
     80A  VAL*     4.0     5.2    -      -       +      -
    122A  GLY      2.9    17.0    +      -       -      +
    123A  ILE      3.6     6.5    -      -       -      +
    124A  LYS      3.3     0.2    -      -       -      -
    125A  GLN*     1.3    75.5    -      -       -      +
    127A  ASP*     1.3    59.9    +      -       +      +
    129A  VAL*     3.3     5.0    +      -       -      +
    130A  THR*     2.9    56.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with ASP 127 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      5A  LEU*     4.5    22.1    +      -       +      +
    123A  ILE      3.2     9.7    +      -       -      +
    124A  LYS*     3.6    11.8    -      -       -      +
    125A  GLN      3.2     0.6    -      -       -      -
    126A  TYR*     1.3    80.1    -      -       +      +
    128A  LEU*     1.3    63.4    +      -       -      +
    130A  THR*     3.9     7.1    +      -       -      -
    131A  SER*     2.8    35.0    +      -       -      -
    132B  LYS*     3.0    36.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 128 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    124A  LYS*     3.2    31.0    +      -       +      +
    125A  GLN*     3.4    27.4    -      -       -      +
    127A  ASP*     1.3    76.8    -      -       -      +
    129A  VAL*     1.3    63.3    +      -       -      +
    131A  SER*     3.8     3.5    -      -       -      -
    132A  LYS*     3.0    25.8    +      -       -      +
    125B  GLN*     4.1     4.5    -      -       -      +
    128B  LEU*     4.0    27.1    -      -       +      +
    129B  VAL*     3.8    30.7    -      -       +      +
    132B  LYS*     3.6    32.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 129 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     78A  ASN*     3.7    43.3    -      -       +      +
     80A  VAL*     5.6     0.9    -      -       +      -
    125A  GLN*     3.2    25.5    +      -       +      +
    126A  TYR*     3.6     9.6    -      -       -      +
    128A  LEU*     1.3    77.6    -      -       -      +
    130A  THR*     1.3    58.3    +      -       +      +
    132A  LYS*     3.7     2.8    -      -       -      +
    133A  GLU*     3.0    26.2    +      -       +      +
    124B  LYS*     6.1     1.1    -      -       -      +
    128B  LEU*     3.8    27.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with THR 130 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     78A  ASN*     3.9    22.7    -      -       +      +
    126A  TYR*     2.9    58.8    +      -       +      +
    127A  ASP*     3.9     8.0    +      -       -      -
    129A  VAL*     1.3    74.4    -      -       -      +
    131A  SER*     1.3    58.7    +      -       -      +
    133A  GLU*     3.7     9.6    -      -       -      +
    134A  GLU*     2.7    40.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 131 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    127A  ASP*     2.8    23.5    +      -       -      -
    128A  LEU      3.8     2.9    -      -       -      -
    130A  THR*     1.3    76.2    +      -       -      +
    132A  LYS*     1.3    66.1    +      -       -      +
    134A  GLU*     3.4    20.7    +      -       -      +
    135A  LEU*     3.2    23.2    +      -       -      +
    132B  LYS*     3.4    33.8    -      -       -      +
    135B  LEU*     3.6    15.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 132 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    128A  LEU      3.0    17.9    +      -       -      +
    129A  VAL      3.7     4.0    -      -       -      +
    130A  THR      3.3     0.2    -      -       -      -
    131A  SER*     1.3    76.1    +      -       -      +
    133A  GLU*     1.3    64.6    +      -       -      +
    135A  LEU*     3.2    16.9    +      -       +      +
    136A  LEU*     3.0    50.9    +      -       +      +
    127B  ASP*     3.1    31.4    +      -       -      +
    128B  LEU*     3.7    23.3    -      -       +      +
    131B  SER*     3.7    25.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 133 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     78A  ASN*     3.6    31.9    +      -       -      +
    129A  VAL*     3.0    17.8    +      -       +      +
    130A  THR*     3.8     8.3    -      -       -      +
    132A  LYS*     1.3    79.2    -      -       -      +
    134A  GLU*     1.3    58.7    +      -       -      +
    135A  LEU      3.0     0.4    +      -       -      -
    136A  LEU*     3.1     9.7    +      -       -      +
    137A  LYS*     2.9    42.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 134 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    130A  THR*     2.7    24.8    +      -       -      +
    131A  SER*     3.4    23.2    +      -       -      +
    132A  LYS      3.3     0.2    -      -       -      -
    133A  GLU*     1.3    75.1    -      -       -      +
    135A  LEU*     1.3    60.7    +      -       +      +
    137A  LYS*     3.9     8.5    +      -       -      +
    138A  LYS*     2.9    34.0    +      -       +      +
    135B  LEU*     6.5     0.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 135 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    131A  SER*     3.2    13.7    +      -       -      +
    132A  LYS*     3.2    19.8    +      -       +      +
    133A  GLU      3.0     1.0    -      -       -      -
    134A  GLU*     1.3    80.9    -      -       +      +
    136A  LEU*     1.3    74.3    +      -       +      +
    137A  LYS      3.4     0.2    -      -       -      -
    138A  LYS*     4.1     4.0    -      -       -      +
    139A  THR*     3.3    26.4    +      -       -      -
    131B  SER*     3.9    14.1    -      -       -      +
    135B  LEU*     3.4    39.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 136 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    132A  LYS*     3.0    47.5    +      -       +      +
    133A  GLU*     3.7    10.5    -      -       +      +
    135A  LEU*     1.3    85.2    -      -       +      +
    137A  LYS*     1.3    64.2    +      -       -      +
    138A  LYS      3.2     1.1    +      -       -      -
    139A  THR      3.3    17.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 137 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    133A  GLU*     2.9    30.8    +      -       +      +
    134A  GLU*     3.9     9.7    -      -       -      +
    135A  LEU      3.4     0.2    -      -       -      -
    136A  LEU*     1.3    78.3    -      -       -      +
    138A  LYS*     1.3    70.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 138 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    134A  GLU*     2.9    25.0    +      -       +      +
    135A  LEU*     4.8     2.7    -      -       -      +
    137A  LYS*     1.3    93.6    -      -       +      +
    139A  THR*     1.3    63.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 139 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    135A  LEU*     3.3    24.7    +      -       -      -
    136A  LEU*     3.3    17.6    +      -       -      -
    138A  LYS*     1.3    84.8    -      -       -      +
----------------------------------------------------------
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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