Contacts of the helix formed by residues 63 - 88 (chain B) in PDB entry 2RGZ


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 LYS 63 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     61B  ASN*     5.5     2.7    -      -       -      +
     62B  ILE*     1.3    83.3    -      -       -      +
     64B  LYS*     1.3    50.4    +      -       -      +
     65B  GLU      2.6     3.5    +      -       -      +
     66B  LEU*     2.3    45.2    +      -       +      +
     67B  PHE      4.3     2.0    -      -       -      -
    241B  GLY*     5.9     0.7    -      -       -      +
    244B  LEU*     3.9    35.4    -      -       +      +
    245B  ALA*     5.8     5.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 64 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     63B  LYS*     1.3    66.7    -      -       -      +
     65B  GLU*     1.3    64.6    +      -       +      +
     66B  LEU      3.0     0.2    +      -       -      -
     67B  PHE*     3.0     8.4    +      -       -      +
     68B  LYS*     2.9    39.9    +      -       +      +
    115B  TYR*     5.4    11.0    +      -       -      -
    116B  PHE*     3.9    37.0    +      -       +      +
    175B  LEU*     3.3    37.2    -      -       +      +
    177B  LEU*     5.8     2.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 65 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     63B  LYS*     2.6     6.1    +      -       -      +
     64B  LYS*     1.3    81.4    -      -       +      +
     66B  LEU*     1.3    57.5    +      -       -      +
     68B  LYS*     2.7    45.0    +      -       -      +
     69B  LEU*     3.5    21.4    +      -       -      +
    117B  PHE*     4.9     6.4    -      -       -      -
    244B  LEU*     4.0    20.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 66 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     53B  PHE*     4.2    11.2    -      -       +      -
     62B  ILE*     3.4    29.6    -      -       +      -
     63B  LYS*     2.3    38.4    +      -       +      +
     65B  GLU*     1.3    65.0    -      -       -      +
     67B  PHE*     1.3    54.3    +      -       -      +
     68B  LYS      2.8     4.7    -      -       -      -
     69B  LEU*     2.6    49.7    +      -       +      +
     70B  ALA*     3.0    11.3    +      -       -      +
    237B  LEU*     3.2    35.0    -      -       +      +
    238B  ASP*     5.1     2.5    -      -       -      +
    241B  GLY*     3.6    27.1    -      -       -      +
    244B  LEU*     4.6     4.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 67 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     53B  PHE*     5.6     0.9    -      -       -      -
     57B  PHE*     3.4    42.2    -      +       -      -
     62B  ILE*     4.5    12.2    -      -       +      +
     63B  LYS      3.5     2.0    +      -       -      -
     64B  LYS*     3.3    11.0    -      -       -      +
     66B  LEU*     1.3    80.0    -      -       -      +
     68B  LYS*     1.3    51.9    +      -       -      +
     70B  ALA*     3.5    10.1    +      -       +      +
     71B  THR*     2.7    51.8    +      -       -      -
    112B  ASP*     6.3     0.2    -      -       +      -
    116B  PHE*     3.5    35.9    -      +       -      -
    171B  ALA*     3.7    18.4    -      -       +      -
    175B  LEU*     3.6    21.8    -      -       +      -
    184B  THR*     3.8    17.7    -      -       +      -
    187B  TYR*     4.0    17.7    -      +       -      -
----------------------------------------------------------
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Residues in contact with LYS 68 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     64B  LYS*     2.9    27.3    +      -       +      +
     65B  GLU*     2.7    45.4    +      -       -      +
     66B  LEU      2.8     0.2    -      -       -      -
     67B  PHE*     1.3    77.5    -      -       -      +
     69B  LEU*     1.3    57.3    +      -       -      +
     71B  THR*     4.3     5.4    -      -       -      -
     72B  THR*     2.7    34.3    +      -       -      -
    113B  MET*     3.4     1.0    -      -       -      +
    116B  PHE*     3.1    61.4    +      -       +      -
    117B  PHE*     3.1    40.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 69 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     65B  GLU      3.6    11.4    -      -       -      +
     66B  LEU*     2.6    38.3    +      -       +      +
     68B  LYS*     1.3    73.8    -      -       -      +
     70B  ALA*     1.3    62.1    +      -       -      +
     72B  THR*     3.0    10.8    +      -       -      -
     73B  ALA*     2.9    20.3    +      -       -      +
    117B  PHE*     5.6     5.4    -      -       +      -
    128B  PRO*     4.7    11.9    -      -       +      +
    236B  GLU*     5.6     0.7    -      -       -      +
    237B  LEU*     3.4    17.8    -      -       +      +
    240B  ALA*     3.7    23.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 70 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     53B  PHE*     4.2    15.5    -      -       +      -
     57B  PHE*     6.2     0.4    -      -       +      -
     66B  LEU      3.0     8.4    +      -       -      +
     67B  PHE*     3.6    13.9    -      -       +      +
     69B  LEU*     1.3    76.4    -      -       -      +
     71B  THR*     1.3    58.2    +      -       -      +
     73B  ALA*     2.8    24.3    +      -       -      +
     74B  LEU*     2.9    19.7    +      -       +      +
    237B  LEU*     3.4    28.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with THR 71 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     67B  PHE*     2.7    43.2    +      -       +      -
     68B  LYS*     4.0     1.7    -      -       -      -
     70B  ALA*     1.3    76.8    -      -       -      +
     72B  THR*     1.3    55.6    +      -       -      +
     74B  LEU*     3.3    13.8    +      -       +      +
     75B  TYR*     3.0    26.3    +      -       -      +
    109B  LEU*     3.8    20.7    -      -       +      +
    112B  ASP*     4.0    20.2    -      -       +      +
    113B  MET*     3.1    31.8    -      -       +      +
    116B  PHE*     4.8     1.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with THR 72 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     68B  LYS      2.7    18.8    +      -       -      -
     69B  LEU*     3.0    14.4    +      -       +      -
     71B  THR*     1.3    74.9    -      -       -      +
     73B  ALA*     1.3    66.5    +      -       -      +
     75B  TYR*     3.2     8.4    +      -       -      +
     76B  PHE*     3.1    47.5    +      -       +      -
    113B  MET*     3.3    12.7    -      -       -      +
    117B  PHE*     3.0    22.2    -      -       +      -
    125B  VAL*     4.4    11.9    -      -       +      +
    126B  GLN      3.8    14.4    -      -       -      +
    128B  PRO*     3.9     6.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 73 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     69B  LEU      2.9    10.1    +      -       -      +
     70B  ALA*     2.8    13.1    +      -       -      +
     72B  THR*     1.3    79.5    -      -       -      +
     74B  LEU*     1.3    58.7    +      -       +      +
     76B  PHE*     3.3     2.1    +      -       -      +
     77B  THR*     2.9    33.8    +      -       -      -
    128B  PRO*     4.0    22.2    -      -       +      +
    131B  ALA*     4.1     8.1    -      -       +      +
    233B  ILE*     4.1    27.6    -      -       +      -
    237B  LEU*     5.5     1.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 74 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     70B  ALA*     2.9    18.5    +      -       +      +
     71B  THR*     3.4    14.6    -      -       +      +
     73B  ALA*     1.3    78.8    -      -       +      +
     75B  TYR*     1.3    56.8    +      -       -      +
     77B  THR*     4.4     4.0    -      -       +      -
     78B  TYR*     2.8    60.2    +      -       +      +
    109B  LEU*     3.6    19.1    -      -       +      -
    156B  ARG*     3.8    19.1    -      -       -      +
    186B  PHE*     3.6    31.9    -      -       +      -
    187B  TYR*     4.7     8.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 75 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     71B  THR      3.0    13.4    +      -       -      +
     72B  THR*     3.2     9.4    +      -       -      +
     74B  LEU*     1.3    76.0    -      -       -      +
     76B  PHE*     1.3    88.1    +      +       -      +
     78B  TYR*     4.5     0.3    -      -       -      +
     79B  SER*     3.1    32.6    +      -       -      -
    106B  LYS*     3.7    30.7    +      -       +      +
    109B  LEU*     3.7    13.4    -      -       +      +
    110B  THR*     3.3    43.5    +      -       +      +
    113B  MET*     4.4    11.4    -      -       +      -
    121B  TRP*     4.3    11.2    -      +       -      -
    122B  GLU*     3.5    30.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with PHE 76 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     72B  THR*     3.1    44.4    +      -       +      +
     73B  ALA*     4.0     3.1    -      -       -      +
     75B  TYR*     1.3   100.9    -      +       -      +
     77B  THR*     1.3    67.6    +      -       -      +
     79B  SER*     3.6     4.3    +      -       -      -
     80B  ALA*     3.3    15.9    +      -       -      +
    121B  TRP*     5.8     0.2    -      +       -      -
    122B  GLU*     4.9     4.5    -      -       -      -
    125B  VAL*     3.9    21.8    -      -       +      -
    126B  GLN*     3.8     1.3    -      -       -      -
    127B  ALA*     3.4    47.6    -      -       +      -
    128B  PRO*     4.4     0.4    -      -       +      -
    131B  ALA*     5.3     2.2    -      -       +      -
    135B  VAL*     3.4    20.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with THR 77 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     73B  ALA      2.9    21.8    +      -       -      -
     74B  LEU*     3.8     6.5    -      -       +      -
     76B  PHE*     1.3    79.1    -      -       -      +
     78B  TYR*     1.3    71.4    +      -       +      +
     80B  ALA*     3.3     2.9    +      -       -      +
     81B  LEU*     3.0    27.9    +      -       +      +
    131B  ALA*     4.3    12.1    +      -       -      +
    134B  TYR*     3.7    39.1    -      -       +      -
    135B  VAL*     3.9    10.0    -      -       -      +
    138B  ILE*     4.0     7.7    -      -       +      +
    156B  ARG*     4.8     8.7    -      -       +      -
    233B  ILE*     4.4     4.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 78 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     74B  LEU*     2.8    59.9    +      -       +      +
     75B  TYR      4.5     0.7    -      -       -      +
     77B  THR*     1.3    75.6    -      -       +      +
     79B  SER*     1.3    59.8    +      -       -      +
     81B  LEU*     4.4     5.8    -      -       +      -
     82B  GLU*     2.8    43.7    +      -       -      +
    105B  ARG*     3.6    15.0    -      -       +      -
    106B  LYS*     4.8     2.7    -      -       -      +
    109B  LEU*     4.1    15.5    -      -       +      -
    156B  ARG*     2.9    34.1    +      -       +      +
    157B  TYR*     3.3    43.1    -      +       -      -
    160B  ASP*     2.6    34.9    +      -       -      -
    186B  PHE*     4.0     8.1    -      +       -      -
----------------------------------------------------------
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Residues in contact with SER 79 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75B  TYR*     3.1    29.4    +      -       -      -
     76B  PHE*     4.0     6.5    -      -       -      -
     77B  THR      3.3     0.4    -      -       -      -
     78B  TYR*     1.3    77.7    -      -       -      +
     80B  ALA*     1.3    62.2    +      -       -      +
     82B  GLU*     4.1     1.9    -      -       -      +
     83B  GLU*     3.1    23.6    +      -       -      +
    106B  LYS*     3.2    46.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 80 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     76B  PHE      3.3    16.1    +      -       -      +
     77B  THR      3.6     4.0    -      -       -      +
     78B  TYR      3.1     0.2    -      -       -      -
     79B  SER*     1.3    77.8    -      -       -      +
     81B  LEU*     1.3    66.2    +      -       -      +
     83B  GLU*     3.2     3.3    +      -       -      +
     84B  GLU*     3.1    26.9    +      -       -      +
    135B  VAL*     4.0    14.8    -      -       +      -
    138B  ILE*     3.8    12.3    -      -       +      -
    139B  HIS*     3.2    33.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 81 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     77B  THR*     3.0    19.0    +      -       +      +
     78B  TYR*     4.0     8.3    -      -       +      +
     80B  ALA*     1.3    76.5    -      -       -      +
     82B  GLU*     1.3    61.3    +      -       -      +
     84B  GLU*     3.5     1.4    +      -       -      +
     85B  MET*     3.1    34.7    +      -       +      +
    134B  TYR*     5.4     1.1    -      -       -      +
    138B  ILE*     3.4    28.6    -      -       +      +
    149B  LEU*     3.7    15.7    -      -       +      -
    152B  HIS*     3.7    42.4    -      -       +      +
    153B  ALA*     4.5     1.1    -      -       -      +
    156B  ARG*     4.5    13.0    -      -       +      -
    157B  TYR*     3.6    31.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 82 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     78B  TYR*     2.8    22.7    +      -       -      +
     79B  SER*     4.1     4.3    -      -       -      +
     81B  LEU*     1.3    75.5    -      -       -      +
     83B  GLU*     1.3    64.7    +      -       -      +
     85B  MET*     3.5     6.8    +      -       -      +
     86B  GLU*     3.1    21.8    +      -       -      +
    104B  HIS*     3.2    46.6    +      -       +      +
    105B  ARG*     2.6    26.6    +      -       -      -
    106B  LYS*     2.9    30.6    +      -       +      +
    157B  TYR*     3.2    22.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 83 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     79B  SER      3.1    20.2    +      -       -      +
     80B  ALA*     3.2     5.1    +      -       -      +
     82B  GLU*     1.3    76.3    -      -       -      +
     84B  GLU*     1.3    60.9    +      -       -      +
     86B  GLU*     3.0    11.3    +      -       +      +
     87B  ARG*     2.8    55.7    +      -       +      +
    139B  HIS*     4.3    12.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 84 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     80B  ALA      3.1    16.5    +      -       -      +
     81B  LEU      3.8     5.2    -      -       -      +
     83B  GLU*     1.3    79.0    -      -       -      +
     85B  MET*     1.3    56.6    +      -       -      +
     87B  ARG*     2.6    48.2    +      -       -      +
     88B  ASN*     2.8    34.7    +      -       -      -
    138B  ILE*     3.1    26.0    -      -       +      +
    139B  HIS*     2.8    33.3    +      -       -      +
    142B  GLY*     3.2    22.8    -      -       -      -
    143B  GLN*     3.3     4.0    +      -       -      -
    149B  LEU*     3.8    11.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with MET 85 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     81B  LEU*     3.1    25.2    +      -       +      +
     82B  GLU*     3.9     6.7    -      -       -      +
     84B  GLU*     1.3    73.5    -      -       -      +
     86B  GLU*     1.3    62.5    +      -       -      +
     88B  ASN      3.4     1.1    -      -       -      +
     89B  LYS*     2.8    31.2    +      -       -      +
     94B  PHE*     3.1    39.0    -      -       +      -
     97B  LEU      4.6     6.7    -      -       -      +
     98B  TYR*     3.8    13.9    -      -       +      -
     99B  PHE      6.3     0.4    -      -       -      -
    103B  LEU*     6.5     0.7    -      -       +      -
    104B  HIS*     4.5    10.3    -      -       -      +
    149B  LEU*     3.8    16.4    -      -       +      +
    153B  ALA*     3.2    30.7    -      -       +      -
    157B  TYR*     4.0    29.2    -      -       +      -
    202B  TYR*     4.9     0.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 86 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     82B  GLU      3.1    14.3    +      -       -      +
     83B  GLU*     3.0    15.0    +      -       +      +
     85B  MET*     1.3    77.6    -      -       -      +
     87B  ARG*     1.3    61.9    +      -       -      +
     89B  LYS*     3.1    41.1    +      -       -      +
     98B  TYR*     3.0    28.4    +      -       +      +
    104B  HIS*     5.7     2.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 87 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     83B  GLU*     2.8    33.3    +      -       -      +
     84B  GLU*     2.6    48.8    +      -       -      +
     86B  GLU*     1.3    78.6    -      -       -      +
     88B  ASN*     1.3    59.6    +      -       -      +
     89B  LYS*     3.4     2.6    +      -       -      +
     90B  ASP      4.9     1.0    +      -       -      -
    139B  HIS*     4.8     0.6    +      -       -      -
    142B  GLY      3.9    16.4    -      -       -      -
    143B  GLN*     3.7    25.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 88 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     84B  GLU      2.8    27.2    +      -       -      +
     85B  MET      3.2     2.7    +      -       -      +
     87B  ARG*     1.3    81.4    -      -       -      +
     89B  LYS*     1.3    64.8    +      -       -      +
     90B  ASP      3.2     3.1    -      -       -      -
     91B  HIS*     2.8    34.7    +      -       +      +
     94B  PHE*     3.8    16.2    -      -       +      +
    142B  GLY*     2.9    35.3    +      -       -      +
    146B  PRO*     3.3    26.7    -      -       -      +
    149B  LEU*     3.8    15.0    -      -       +      +
----------------------------------------------------------
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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