Contacts of the helix formed by residues 37 - 64 (chain A) in PDB entry 2GS4


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 ASN 37 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     35A  THR*     3.1     8.0    +      -       -      +
     36A  SER*     1.3    76.2    +      -       -      +
     38A  GLU*     1.3    57.8    +      -       -      +
     39A  LYS*     2.9    14.0    +      -       -      +
     40A  LEU*     2.6    39.2    +      -       +      +
     41A  SER*     2.8    25.7    +      -       -      -
     99A  ASP*     3.4    27.3    +      -       -      +
    103A  ILE*     5.8     2.8    -      -       -      +
    153A  LEU*     5.8     3.6    +      -       -      +
    157A  ASN*     5.3     5.9    +      -       -      +
    160A  LYS*     4.2    22.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 38 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     36A  SER      3.2     9.0    +      -       -      +
     37A  ASN*     1.3    71.2    +      -       -      +
     39A  LYS*     1.3    63.1    +      -       +      +
     41A  SER*     3.4     9.7    +      -       -      -
     42A  GLN*     3.0    61.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 39 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     37A  ASN*     2.9     9.0    +      -       -      +
     38A  GLU*     1.3    82.3    -      -       +      +
     40A  LEU*     1.3    62.0    +      -       -      +
     42A  GLN*     3.6    21.0    +      -       -      +
     43A  ALA*     3.2    20.6    +      -       -      +
    153A  LEU*     4.4    19.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 40 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     35A  THR*     3.9    19.5    -      -       +      +
     37A  ASN*     2.6    28.8    +      -       +      +
     39A  LYS*     1.3    71.1    -      -       -      +
     41A  SER*     1.3    65.9    +      -       -      +
     43A  ALA*     3.0    13.4    +      -       +      +
     44A  PHE*     3.0    46.9    +      -       +      -
     99A  ASP*     4.0    19.5    -      -       +      +
    102A  LEU*     4.3     5.4    -      -       +      -
    103A  ILE*     3.8    32.8    -      -       +      -
    150A  LEU*     4.6     5.8    -      -       +      -
    153A  LEU*     4.2    19.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with SER 41 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     32A  ALA*     2.7    38.4    +      -       -      +
     35A  THR*     3.9    13.1    +      -       -      +
     37A  ASN      2.8    15.5    +      -       -      -
     38A  GLU*     3.5    13.2    +      -       -      -
     40A  LEU*     1.3    76.8    -      -       -      +
     42A  GLN*     1.3    58.5    +      -       -      +
     44A  PHE*     3.3     2.3    +      -       -      -
     45A  HIS*     3.0    27.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 42 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     38A  GLU*     3.0    46.3    +      -       +      +
     39A  LYS*     3.8    24.1    -      -       -      +
     40A  LEU      3.1     0.2    -      -       -      -
     41A  SER*     1.3    76.2    -      -       -      +
     43A  ALA*     1.3    54.6    +      -       -      +
     45A  HIS*     3.2     7.7    +      -       -      +
     46A  ALA*     2.7    35.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 43 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39A  LYS      3.2    13.5    +      -       -      +
     40A  LEU*     3.0    12.2    +      -       +      +
     42A  GLN*     1.3    76.7    -      -       -      +
     44A  PHE*     1.3    59.2    +      -       -      +
     46A  ALA*     3.7     6.9    -      -       -      +
     47A  HIS*     2.9    29.1    +      -       -      +
    146A  THR*     5.7     1.0    -      -       -      +
    149A  LYS*     4.7    12.3    -      -       +      -
    150A  LEU*     5.3     6.7    -      -       +      -
    153A  LEU*     3.8    23.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 44 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     28A  LEU*     4.0    19.7    -      -       +      +
     31A  LEU*     3.6    53.2    -      -       +      -
     32A  ALA*     3.8    17.7    -      -       +      +
     35A  THR*     4.6     1.6    -      -       +      -
     40A  LEU*     3.0    54.5    +      -       +      -
     41A  SER*     3.6     5.8    -      -       -      +
     43A  ALA*     1.3    75.0    -      -       -      +
     45A  HIS*     1.3    62.0    +      -       -      +
     47A  HIS*     3.3     5.6    +      -       +      +
     48A  LEU*     2.9    28.6    +      -       -      +
    102A  LEU*     4.0    23.8    -      -       +      -
    106A  ALA*     3.6    24.5    -      -       +      -
    150A  LEU*     4.7     6.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with HIS 45 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     32A  ALA*     4.1    11.2    -      -       +      +
     41A  SER      3.0    17.4    +      -       -      +
     42A  GLN*     3.6     8.3    -      -       -      +
     44A  PHE*     1.3    75.2    -      -       -      +
     46A  ALA*     1.3    66.0    +      -       -      +
     48A  LEU*     3.2    19.5    +      -       +      +
     49A  GLU*     3.2    48.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 46 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     42A  GLN      2.7    21.7    +      -       -      +
     43A  ALA*     3.7     8.1    -      -       -      +
     45A  HIS*     1.3    76.0    -      -       -      +
     47A  HIS*     1.3    61.9    +      -       -      +
     49A  GLU*     3.2     9.1    +      -       -      +
     50A  GLU*     3.0    22.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 47 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24A  LEU*     4.2    12.8    -      -       +      -
     28A  LEU*     3.8    20.4    -      -       +      +
     43A  ALA      2.9    18.0    +      -       -      +
     44A  PHE*     3.8     6.0    -      -       +      +
     45A  HIS      3.3     0.2    -      -       -      -
     46A  ALA*     1.3    74.0    -      -       -      +
     48A  LEU*     1.3    60.5    +      -       -      +
     50A  GLU*     3.6    25.1    -      -       +      -
     51A  THR*     2.8    49.0    +      -       -      -
     54A  GLN*     4.4     0.2    +      -       -      -
    109A  VAL*     5.4     0.2    -      -       +      -
    110A  GLU*     2.9    31.2    +      -       -      -
    143A  GLU*     3.0    25.6    +      -       -      -
    146A  THR*     3.8    20.4    -      -       +      +
    150A  LEU*     6.3     0.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 48 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     25A  THR*     3.4    30.3    -      -       -      +
     28A  LEU*     3.7    14.3    -      -       +      +
     29A  ALA*     4.0    28.9    -      -       +      -
     44A  PHE      2.9    14.3    +      -       -      +
     45A  HIS*     3.3    27.4    -      -       +      +
     46A  ALA      3.2     0.2    -      -       -      -
     47A  HIS*     1.3    76.3    -      -       -      +
     49A  GLU*     1.3    73.0    +      -       -      +
     51A  THR*     3.5     1.6    +      -       -      -
     52A  HIS*     3.3    41.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 49 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     45A  HIS*     3.2    39.8    +      -       +      +
     46A  ALA*     3.6     8.3    -      -       -      +
     47A  HIS      3.2     0.2    -      -       -      -
     48A  LEU*     1.3    85.1    -      -       -      +
     50A  GLU*     1.3    66.0    +      -       -      +
     52A  HIS*     3.1    17.1    +      -       -      +
     53A  GLY*     3.1    17.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 50 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     46A  ALA      3.0    15.6    +      -       -      +
     47A  HIS*     3.6    10.6    -      -       +      +
     49A  GLU*     1.3    75.7    -      -       -      +
     51A  THR*     1.3    56.3    +      -       -      +
     53A  GLY*     3.1     3.8    +      -       -      +
     54A  GLN*     2.9    48.6    +      -       -      +
    142A  GLU*     3.4    29.5    -      -       -      +
    143A  GLU*     2.9    18.7    -      -       -      +
    146A  THR*     2.9    27.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with THR 51 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     21A  GLU*     3.3    45.8    +      -       +      +
     24A  LEU*     4.3     7.8    -      -       +      +
     25A  THR*     4.0    10.5    -      -       +      +
     28A  LEU*     3.4    15.7    -      -       -      +
     47A  HIS*     2.8    39.1    +      -       -      -
     48A  LEU      3.7     5.8    -      -       -      -
     49A  GLU      3.1     0.4    -      -       -      -
     50A  GLU*     1.3    71.1    -      -       -      +
     52A  HIS*     1.3    65.3    +      -       -      +
     54A  GLN*     3.1    11.4    +      -       -      +
     55A  ILE*     3.0    22.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 52 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     25A  THR*     3.8    22.7    -      -       +      +
     48A  LEU*     3.3    39.0    +      -       +      +
     49A  GLU*     3.1    18.7    +      -       -      +
     51A  THR*     1.3    78.4    -      -       -      +
     53A  GLY*     1.3    62.6    +      -       -      +
     55A  ILE*     3.3    14.6    +      -       +      +
     56A  GLU*     3.2    25.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 53 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     49A  GLU      3.1    12.6    +      -       -      -
     50A  GLU*     3.1     6.0    +      -       -      -
     51A  THR      3.1     0.2    -      -       -      -
     52A  HIS*     1.3    79.3    -      -       -      +
     54A  GLN*     1.3    56.6    +      -       -      +
     56A  GLU*     3.2    11.5    +      -       -      +
     57A  ARG*     3.1    30.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 54 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     21A  GLU*     3.4    26.5    -      -       -      +
     50A  GLU*     2.9    31.1    +      -       -      +
     51A  THR*     3.1    17.8    +      -       -      +
     53A  GLY*     1.3    74.5    -      -       -      +
     55A  ILE*     1.3    67.0    +      -       -      +
     57A  ARG*     3.2    11.5    +      -       -      +
     58A  ILE*     3.0    26.8    +      -       -      +
    117A  TYR*     4.5     1.2    +      -       -      +
    139A  THR*     3.7    24.4    +      -       +      +
    142A  GLU*     3.0    30.5    +      -       -      +
    143A  GLU*     2.7    31.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 55 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     18A  TYR*     3.6    31.6    -      -       +      +
     21A  GLU*     3.5    38.1    -      -       +      -
     22A  LYS*     3.9    24.0    -      -       +      +
     25A  THR*     4.0    19.1    -      -       +      -
     51A  THR      3.0    11.2    +      -       -      +
     52A  HIS*     3.6    14.4    -      -       +      +
     53A  GLY      3.2     0.4    -      -       -      -
     54A  GLN*     1.3    75.7    -      -       -      +
     56A  GLU*     1.3    66.9    +      -       -      +
     58A  ILE*     3.0    20.0    +      -       +      +
     59A  ASP*     3.1    16.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 56 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     52A  HIS      3.2    13.8    +      -       -      +
     53A  GLY*     3.2    12.9    +      -       -      +
     55A  ILE*     1.3    82.8    -      -       -      +
     57A  ARG*     1.3    61.5    +      -       -      +
     59A  ASP*     3.1    30.3    +      -       -      +
     60A  GLN*     3.1    18.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 57 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     53A  GLY      3.1    18.6    +      -       -      +
     54A  GLN*     3.4    14.3    -      -       -      +
     55A  ILE      3.1     0.2    -      -       -      -
     56A  GLU*     1.3    78.1    -      -       -      +
     58A  ILE*     1.3    56.9    +      -       +      +
     60A  GLN*     3.1    25.6    +      -       -      +
     61A  VAL*     2.9    28.5    +      -       +      +
    135A  LEU*     3.3    39.6    -      -       +      +
    138A  GLU*     3.6    23.5    +      -       -      +
    139A  THR*     3.0    31.6    +      -       -      +
    142A  GLU*     3.2    36.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 58 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     14A  LEU*     4.4    20.2    -      -       +      +
     17A  THR*     4.1     9.0    -      -       +      -
     18A  TYR*     3.5    48.0    -      -       +      +
     21A  GLU*     4.2     8.3    -      -       +      -
     54A  GLN      3.0    15.7    +      -       -      +
     55A  ILE*     3.0    12.5    +      -       -      +
     57A  ARG*     1.3    73.8    -      -       +      +
     59A  ASP*     1.3    66.4    +      -       -      +
     61A  VAL*     3.1     9.0    +      -       +      +
     62A  VAL*     3.0    22.5    +      -       +      +
     70A  ILE*     4.0    17.9    -      -       +      -
    117A  TYR*     3.7    26.7    -      -       +      +
    136A  LEU*     5.7     1.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASP 59 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     18A  TYR*     3.7    25.6    +      -       -      -
     55A  ILE*     3.1    14.2    +      -       -      +
     56A  GLU*     3.1    30.1    +      -       -      +
     58A  ILE*     1.3    75.3    -      -       -      +
     60A  GLN*     1.3    58.2    +      -       +      +
     62A  VAL*     3.3     7.5    +      -       -      +
     63A  GLU*     3.0    45.4    +      -       -      +
     70A  ILE*     5.8     1.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 60 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     56A  GLU*     3.1    10.8    +      -       +      +
     57A  ARG*     3.1    36.7    +      -       -      +
     58A  ILE      3.1     0.2    -      -       -      -
     59A  ASP*     1.3    78.3    -      -       +      +
     61A  VAL*     1.3    64.7    +      -       -      +
     63A  GLU*     3.3    13.2    +      -       -      +
     64A  SER*     3.0    23.9    +      -       -      -
    131A  LYS*     4.7    14.9    +      -       -      -
    135A  LEU*     3.8    23.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 61 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     10A  PHE*     4.4     8.1    -      -       +      -
     14A  LEU*     3.9    24.2    -      -       +      -
     57A  ARG*     2.9    18.6    +      -       +      +
     58A  ILE*     3.1    12.1    +      -       -      +
     60A  GLN*     1.3    75.9    -      -       -      +
     62A  VAL*     1.3    62.9    +      -       -      +
     64A  SER*     2.6    24.7    +      -       -      -
     68A  LEU*     3.4    14.1    -      -       +      +
    132A  ALA*     3.9    19.1    -      -       +      -
    135A  LEU*     3.9    26.5    -      -       +      -
    136A  LEU*     4.1    22.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 62 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     14A  LEU*     3.9    12.6    -      -       +      -
     58A  ILE*     3.0    13.9    +      -       +      +
     59A  ASP*     3.6    11.0    -      -       -      +
     60A  GLN      3.3     0.2    -      -       -      -
     61A  VAL*     1.3    78.3    -      -       -      +
     63A  GLU*     1.3    60.4    +      -       +      +
     64A  SER      3.4     0.3    +      -       -      -
     65A  GLU      3.0    24.4    +      -       -      +
     68A  LEU*     3.5    31.1    -      -       +      +
     69A  LYS*     4.1    10.8    -      -       -      +
     70A  ILE*     3.6    35.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 63 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     59A  ASP*     3.0    31.5    +      -       -      +
     60A  GLN*     3.8    14.5    -      -       -      +
     62A  VAL*     1.3    74.6    -      -       +      +
     64A  SER*     1.3    59.8    +      -       -      +
     65A  GLU*     3.1     9.9    +      -       -      -
     66A  SER*     4.9     0.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with SER 64 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     60A  GLN      3.0    13.9    +      -       -      -
     61A  VAL*     2.6    22.9    +      -       -      -
     63A  GLU*     1.3    77.2    -      -       -      +
     65A  GLU*     1.3    79.0    +      -       -      +
    131A  LYS*     4.1    34.9    -      -       -      +
    132A  ALA*     4.0    11.6    +      -       -      +
----------------------------------------------------------
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A short description of the analytical approach
The contact analysis used in this page is based upon the approach developed in: Sobolev V., Wade R.C., Vriend G. and Edelman M. PROTEINS (1996) 25, 120-129. Contact legitimacy depends on the hydrophobic-hydrophilic properties of the contacting atoms. In order to define it, for each inter-atomic contact, eight atom classes have been introduced:


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

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

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