Contacts of the helix formed by residues 47 - 71 (chain A) in PDB entry 1ATT


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 ARG 47 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39A  GLN*     4.2     9.4    -      -       -      +
     42A  PRO*     3.4    43.3    -      -       +      +
     44A  ALA*     3.2    19.7    +      -       +      +
     45A  THR*     2.9    35.0    +      -       -      +
     46A  ASN*     1.4   112.0    +      -       -      +
     48A  ARG*     1.3    76.9    +      -       -      +
     49A  VAL*     4.8    11.8    -      -       -      +
     50A  TRP*     4.0    17.0    -      -       +      +
     51A  GLU*     3.8     9.2    -      -       -      +
    126A  LYS*     6.0     0.6    -      -       -      +
    130A  ARG*     4.0    21.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 48 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39A  GLN*     4.1     5.3    -      -       -      +
     45A  THR      4.6     2.7    +      -       -      -
     46A  ASN*     3.0    20.6    +      -       +      +
     47A  ARG*     1.3    89.1    +      -       -      +
     49A  VAL*     1.4    55.1    +      -       -      +
     50A  TRP      2.7     4.6    +      -       -      -
     51A  GLU*     2.5    72.9    +      -       -      +
     52A  LEU*     2.8    11.3    +      -       -      -
    112A  ILE*     4.3     4.5    -      -       +      -
    113A  SER*     2.6    43.3    +      -       -      -
    114A  GLU*     4.9     1.6    -      -       -      +
    123A  PHE*     3.5    50.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 49 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     46A  ASN*     3.9    11.2    +      -       -      +
     47A  ARG*     4.8     9.2    -      -       -      +
     48A  ARG*     1.4    74.8    -      -       +      +
     50A  TRP*     1.3    65.1    +      -       +      +
     52A  LEU*     3.4     8.7    -      -       -      +
     53A  SER*     2.9    21.0    +      -       -      -
    123A  PHE*     3.9    14.1    -      -       +      +
    126A  LYS*     3.7    34.3    -      -       +      -
    127A  LEU*     3.6    31.8    -      -       +      +
    130A  ARG*     5.6     7.2    -      -       +      -
    418A  LEU*     5.1     7.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with TRP 50 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     38A  GLU      3.1    27.6    +      -       -      -
     39A  GLN*     3.3    13.6    -      -       -      +
     40A  LYS*     3.5    54.1    -      -       +      +
     42A  PRO*     4.5     9.4    -      -       +      -
     47A  ARG*     4.0    21.2    -      -       +      +
     48A  ARG      2.7     3.8    +      -       -      +
     49A  VAL*     1.3    73.6    -      -       +      +
     51A  GLU*     1.3    56.2    +      -       -      +
     53A  SER*     2.5    30.5    +      -       -      -
     54A  LYS*     2.9    15.6    +      -       -      +
    416A  VAL      5.3     0.4    -      -       -      -
    417A  ALA      3.8    19.7    -      -       -      -
    418A  LEU*     3.9    14.8    -      -       -      -
    419A  ASN*     4.0    30.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 51 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     37A  SER      3.9    14.9    -      -       -      +
     38A  GLU      4.2     6.5    -      -       -      +
     39A  GLN*     2.7    28.9    +      -       +      +
     47A  ARG      3.8     8.5    -      -       -      +
     48A  ARG*     2.5    48.6    +      -       -      +
     50A  TRP*     1.3    68.8    -      -       +      +
     52A  LEU*     1.3    59.1    +      -       -      +
     54A  LYS*     3.7    11.0    -      -       -      +
     55A  ALA*     2.8    29.3    +      -       -      +
    111A  THR*     4.9     5.0    -      -       +      +
    112A  ILE*     3.8    13.8    +      -       -      +
    113A  SER*     2.9    36.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 52 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     48A  ARG      2.8    12.0    +      -       -      +
     49A  VAL*     3.4    13.7    -      -       -      +
     51A  GLU*     1.3    69.1    -      -       -      +
     53A  SER*     1.3    53.2    +      -       -      +
     55A  ALA*     2.7     7.2    +      -       +      +
     56A  ASN*     2.7    55.9    +      -       -      +
    109A  PHE*     4.2     7.2    -      -       +      -
    112A  ILE*     3.7    30.2    -      -       +      +
    120A  ILE*     5.2     2.2    -      -       +      -
    123A  PHE*     3.5    38.1    -      -       +      +
    124A  PHE*     3.8    24.9    -      -       +      +
    127A  LEU*     4.1    17.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 53 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     49A  VAL      2.9    11.6    +      -       -      -
     50A  TRP*     2.5    25.2    +      -       -      -
     52A  LEU*     1.3    73.7    -      -       -      +
     54A  LYS*     1.3    50.4    +      -       -      +
     56A  ASN*     3.4     6.9    +      -       -      +
     57A  SER*     2.7    42.0    +      -       -      -
    127A  LEU*     3.9     9.8    -      -       -      +
    418A  LEU      3.4     9.5    +      -       -      -
    419A  ASN*     2.8    40.9    +      -       -      -
    420A  THR*     3.8    11.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 54 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     37A  SER*     4.0    10.8    -      -       -      -
     38A  GLU*     3.0    57.1    +      -       -      +
     50A  TRP*     2.9    20.8    +      -       +      +
     51A  GLU*     3.7     9.9    -      -       -      +
     53A  SER*     1.3    77.8    +      -       -      +
     55A  ALA*     1.3    62.0    +      -       -      +
     57A  SER*     3.1     7.0    +      -       -      -
     58A  HIS*     2.9    22.3    +      -       +      +
    111A  THR*     6.4     1.6    -      -       +      -
    302A  PRO*     5.2     6.5    -      -       +      +
    303A  ASP*     4.2    20.9    +      -       -      +
    305A  LEU*     6.0     5.7    -      -       +      +
    419A  ASN*     4.9     4.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 55 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     51A  GLU      2.8    18.2    +      -       -      +
     52A  LEU*     2.7    13.1    +      -       +      +
     54A  LYS*     1.3    69.4    -      -       -      +
     56A  ASN*     1.3    65.1    +      -       -      +
     58A  HIS*     2.9    17.6    +      -       -      +
     59A  PHE*     3.0    10.9    +      -       -      +
    107A  PHE      4.6     1.8    -      -       -      +
    108A  LYS*     3.5    39.2    -      -       -      +
    109A  PHE*     4.7     1.3    -      -       +      +
    111A  THR*     4.3    13.4    -      -       -      +
    112A  ILE*     4.4     8.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASN 56 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     52A  LEU*     2.7    35.7    +      -       -      +
     53A  SER*     3.5    11.7    -      -       -      +
     55A  ALA*     1.3    77.4    -      -       -      +
     57A  SER*     1.3    60.0    +      -       -      +
     59A  PHE*     3.2    11.5    +      -       -      +
     60A  ALA*     2.9    24.9    +      -       -      +
     81A  PRO*     5.3     1.3    -      -       -      +
     82A  LEU*     4.6     9.6    -      -       +      +
     85A  SER*     3.3    34.0    +      -       -      +
    107A  PHE      4.9     2.6    +      -       -      -
    109A  PHE*     3.9    13.1    -      -       -      -
    124A  PHE*     3.8    13.6    -      -       -      -
    127A  LEU*     5.0     4.9    -      -       -      +
    420A  THR*     5.1     5.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with SER 57 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     53A  SER      2.7    22.0    +      -       -      -
     54A  LYS*     3.1     6.7    +      -       -      -
     56A  ASN*     1.3    73.9    -      -       -      +
     58A  HIS*     1.4    52.6    +      -       -      +
     60A  ALA*     3.2    11.8    +      -       -      +
     61A  THR*     2.7    31.6    +      -       -      -
    302A  PRO*     3.9    10.9    -      -       -      +
    419A  ASN*     4.1    12.2    +      -       -      -
    420A  THR*     4.3     1.6    -      -       -      -
    421A  ILE*     3.9    36.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 58 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     54A  LYS*     2.9    10.5    +      -       +      +
     55A  ALA*     2.9    11.8    +      -       -      +
     57A  SER*     1.4    71.1    -      -       -      +
     59A  PHE*     1.3    60.5    +      -       -      +
     61A  THR*     3.1     2.6    +      -       -      -
     62A  ALA*     2.8    46.2    +      -       +      +
    108A  LYS*     3.3    48.2    +      -       +      +
    302A  PRO*     3.6    32.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 59 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     55A  ALA      3.0    10.5    +      -       -      +
     56A  ASN*     3.2     8.9    +      -       -      +
     58A  HIS*     1.3    80.6    -      -       -      +
     60A  ALA*     1.3    55.2    +      -       -      +
     62A  ALA*     4.1     6.7    -      -       +      -
     63A  PHE*     2.6    57.8    +      +       +      +
     81A  PRO*     4.3     6.1    -      -       +      -
     84A  ILE*     3.4    29.8    -      -       +      -
     85A  SER*     3.5    19.7    -      -       -      +
    106A  VAL*     3.6    15.5    -      -       +      -
    107A  PHE*     3.3    49.6    -      +       -      +
    108A  LYS*     4.2     1.3    -      -       -      +
    336A  LEU*     3.9     4.9    -      -       +      -
    339A  MET*     3.4    25.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 60 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     56A  ASN      2.9    12.3    +      -       -      +
     57A  SER*     3.2    15.7    -      -       -      +
     58A  HIS      3.2     0.2    -      -       -      -
     59A  PHE*     1.3    76.6    -      -       -      +
     61A  THR*     1.3    57.4    +      -       -      +
     63A  PHE*     3.9     3.0    -      -       -      +
     64A  TYR*     3.0    27.9    +      -       -      +
     79A  LEU*     5.5     0.5    -      -       -      +
     81A  PRO*     3.4    38.7    -      -       +      +
    421A  ILE*     4.6    11.9    -      -       +      -
    424A  MET*     3.8    11.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 61 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     57A  SER      2.7    17.6    +      -       -      -
     58A  HIS      3.1     4.1    +      -       -      -
     60A  ALA*     1.3    73.8    -      -       -      +
     62A  ALA*     1.3    61.3    +      -       -      +
     64A  TYR*     3.3     3.7    +      -       -      +
     65A  GLN*     2.9    38.8    +      -       -      +
    300A  LEU*     3.6    51.1    -      -       +      -
    301A  THR      4.1     3.1    -      -       -      +
    302A  PRO*     3.4    27.1    -      -       +      +
    308A  TRP*     6.0     2.7    -      -       +      -
    421A  ILE*     5.3     4.1    -      -       +      +
    424A  MET*     4.5     8.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 62 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     58A  HIS*     2.8    36.7    +      -       +      +
     59A  PHE*     3.6     7.4    -      -       +      +
     61A  THR*     1.3    79.4    -      -       -      +
     63A  PHE*     1.3    60.8    +      -       -      +
     65A  GLN*     4.0    10.6    -      -       -      +
     66A  HIS*     3.1    31.6    +      -       +      +
    106A  VAL      5.9     1.3    -      -       -      +
    339A  MET*     4.2    10.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 63 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     59A  PHE*     2.6    42.9    +      +       +      +
     60A  ALA*     3.9     4.0    -      -       -      +
     62A  ALA*     1.3    70.9    -      -       -      +
     64A  TYR*     1.3    59.2    +      -       -      +
     66A  HIS*     3.6     2.3    +      -       -      +
     67A  LEU*     2.9    29.6    +      -       +      +
     79A  LEU*     3.3    35.7    -      -       +      -
     81A  PRO*     6.0     1.8    -      -       +      -
     84A  ILE*     3.9     8.5    -      -       +      -
    330A  PHE*     3.7    19.3    -      +       -      -
    332A  VAL*     3.5    34.8    -      -       +      -
    335A  GLN*     4.0    22.7    -      -       +      -
    336A  LEU*     4.4     3.1    -      -       +      -
    339A  MET*     3.2    30.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 64 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     60A  ALA      3.0    19.5    +      -       -      +
     61A  THR      3.8     3.4    -      -       -      +
     63A  PHE*     1.3    77.5    -      -       -      +
     65A  GLN*     1.3    61.6    +      -       +      +
     67A  LEU*     3.1     4.2    +      -       -      +
     68A  ALA*     2.7    42.5    +      -       +      +
     77A  ILE*     3.6    31.9    -      -       +      +
     79A  LEU*     5.0     8.1    -      -       +      -
    297A  GLU*     2.7    43.4    +      -       +      +
    300A  LEU*     4.4    20.0    -      -       +      -
    410A  LEU*     4.5     8.3    -      -       +      +
    424A  MET*     3.8    29.4    -      -       +      -
    425A  GLY*     3.8    16.7    +      -       -      -
    426A  ARG*     3.3    20.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 65 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     61A  THR*     2.9    24.0    +      -       -      +
     62A  ALA*     4.0     8.3    -      -       -      +
     64A  TYR*     1.3    79.4    -      -       +      +
     66A  HIS*     1.3    66.1    +      -       +      +
     68A  ALA*     3.5     3.3    +      -       -      +
     69A  ASP*     3.2    22.2    +      -       -      +
    297A  GLU      3.1    22.4    -      -       -      +
    298A  GLN*     2.8    29.5    -      -       -      +
    299A  GLU      3.8     0.2    -      -       -      -
    300A  LEU*     3.1    32.6    +      -       +      +
    301A  THR*     5.7     0.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 66 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     62A  ALA*     3.1    18.5    +      -       +      +
     63A  PHE      3.6     5.8    -      -       -      +
     64A  TYR      3.2     0.2    -      -       -      -
     65A  GLN*     1.3    80.3    -      -       +      +
     67A  LEU*     1.3    64.5    +      -       -      +
     68A  ALA      3.0     1.0    +      -       -      -
     69A  ASP*     3.0    15.9    +      -       -      +
     70A  SER*     3.1    14.6    +      -       -      -
    335A  GLN*     4.5    13.2    -      -       +      -
    338A  ASP*     4.1    32.1    +      -       +      +
    339A  MET*     3.0    39.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 67 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     63A  PHE*     2.9    23.8    +      -       +      +
     64A  TYR*     3.1     3.8    +      -       -      +
     66A  HIS*     1.3    71.2    -      -       -      +
     68A  ALA*     1.3    56.7    +      -       -      +
     70A  SER*     3.2     5.8    +      -       -      -
     71A  LYS*     2.9    54.6    +      -       +      +
     77A  ILE*     3.5    19.3    -      -       +      -
     79A  LEU*     3.5    17.7    -      -       +      -
    330A  PHE*     3.4    45.8    -      -       +      -
    335A  GLN*     4.0    22.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 68 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     64A  TYR*     2.7    30.0    +      -       +      +
     65A  GLN*     3.9     4.7    -      -       -      +
     67A  LEU*     1.3    69.6    -      -       -      +
     69A  ASP*     1.3    61.6    +      -       -      +
     71A  LYS      2.8    25.9    -      -       -      +
     73A  ASN*     4.6     4.9    +      -       -      -
     77A  ILE*     3.6    27.3    -      -       +      +
    297A  GLU*     3.8    24.6    -      -       +      +
    426A  ARG*     4.2     5.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 69 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     65A  GLN      3.2    16.6    +      -       -      +
     66A  HIS*     3.3     8.8    +      -       -      +
     68A  ALA*     1.3    80.5    -      -       -      +
     70A  SER*     1.3    65.7    +      -       -      +
     71A  LYS      3.0     5.0    +      -       -      +
     73A  ASN*     5.7     1.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 70 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     66A  HIS      3.1    13.0    +      -       -      -
     67A  LEU*     3.2    11.0    +      -       -      -
     69A  ASP*     1.3    79.4    +      -       -      +
     71A  LYS*     1.3    59.5    +      -       -      +
     72A  ASN      3.8     1.4    +      -       -      -
    334A  GLU*     5.3     3.6    -      -       -      -
    335A  GLN*     3.5    26.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 71 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     67A  LEU*     2.9    39.6    +      -       +      +
     68A  ALA      2.8    20.5    -      -       -      +
     69A  ASP      3.0     4.3    +      -       -      +
     70A  SER*     1.3    77.0    -      -       -      +
     72A  ASN*     1.3    68.9    +      -       -      +
     73A  ASN*     3.2     5.9    +      -       -      -
     75A  ASP*     4.3    15.7    +      -       +      +
     76A  ASN      3.6     9.9    +      -       -      +
     77A  ILE*     3.8    19.3    -      -       +      -
    328A  ASP*     3.2    31.4    +      -       -      -
    329A  SER      5.1     4.1    +      -       -      -
    330A  PHE*     5.0     7.0    -      -       -      -
    426A  ARG*     3.8    12.3    +      -       -      +
----------------------------------------------------------
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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