Contacts of the helix formed by residues 90 - 115 (chain F) in PDB entry 4GTU


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 GLU 90 (chain F).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     67E  HIS*     5.4     6.5    -      -       +      +
     78E  TYR*     3.2    19.8    +      -       +      +
     81E  ARG*     2.9    46.4    +      -       -      +
     82E  LYS*     4.3    14.8    +      -       -      +
     89F  THR*     1.3    71.5    -      -       -      +
     91F  GLU*     1.3    61.1    +      -       +      +
     93F  LYS*     3.5    23.2    +      -       +      +
     94F  ILE*     3.0    34.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 91 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     67E  HIS*     5.7    10.8    -      -       +      +
     89F  THR*     2.9    12.8    +      -       -      +
     90F  GLU*     1.3    80.5    -      -       +      +
     92F  GLU*     1.3    61.9    +      -       +      +
     94F  ILE*     3.9     7.1    +      -       -      +
     95F  ARG*     2.8    29.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 92 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     87F  GLY*     4.3     2.7    -      -       -      -
     88F  GLU*     3.2    37.7    -      -       -      +
     89F  THR*     2.6    29.3    +      -       -      +
     91F  GLU*     1.3    72.5    -      -       +      +
     93F  LYS*     1.3    62.8    +      -       -      +
     95F  ARG*     3.5     7.7    +      -       -      -
     96F  VAL*     3.1    27.9    +      -       -      +
    148F  VAL*     3.4    26.7    -      -       +      +
    149F  GLY*     5.1     0.2    -      -       -      -
    150F  ASP*     4.9     2.9    +      -       -      +
    151F  LYS*     3.3    33.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 93 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     81E  ARG*     3.8    33.7    -      -       -      +
     87F  GLY*     4.1    19.3    -      -       -      -
     88F  GLU      3.4    25.0    +      -       -      -
     89F  THR      2.8     8.9    +      -       -      +
     90F  GLU*     3.5    30.9    +      -       -      +
     92F  GLU*     1.3    73.4    -      -       -      +
     94F  ILE*     1.3    66.6    +      -       -      +
     96F  VAL*     2.9    10.9    +      -       -      +
     97F  ASP*     2.9    26.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 94 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     67E  HIS*     4.1    22.2    -      -       +      -
     68E  LYS      5.2     1.1    -      -       -      +
     69E  ILE*     3.5    27.1    -      -       +      -
     78E  TYR*     3.4    27.8    -      -       +      -
     81E  ARG*     3.8    20.9    -      -       -      +
     90F  GLU*     3.0    21.8    +      -       +      +
     91F  GLU*     4.2     5.8    -      -       -      +
     93F  LYS*     1.3    74.0    -      -       -      +
     95F  ARG*     1.3    65.7    +      -       +      +
     97F  ASP*     3.0     4.1    +      -       +      +
     98F  ILE*     2.9    44.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 95 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     55E  ASP*     5.0     2.6    +      -       -      -
     91F  GLU*     2.8    23.3    +      -       -      +
     92F  GLU*     3.7     9.4    -      -       -      +
     93F  LYS      3.2     0.2    -      -       -      -
     94F  ILE*     1.3    74.1    -      -       +      +
     96F  VAL*     1.3    59.0    +      -       -      +
     98F  ILE*     4.0     0.8    -      -       -      +
     99F  LEU*     2.8    37.0    +      -       -      +
    140F  PHE*     3.4    60.9    +      -       +      +
    144F  ARG*     3.7    30.6    -      -       -      +
    147F  PHE      2.8    25.8    +      -       -      +
    148F  VAL*     3.9    28.0    -      -       +      +
    155F  VAL*     5.7     0.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 96 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     86F  CYS*     4.5     4.5    -      -       +      -
     87F  GLY*     4.1    20.4    -      -       -      +
     92F  GLU      3.1    15.7    +      -       -      +
     93F  LYS*     2.9    13.6    +      -       -      +
     95F  ARG*     1.3    76.1    -      -       -      +
     97F  ASP*     1.3    58.1    +      -       -      +
    100F  GLU*     2.8    40.7    +      -       -      +
    148F  VAL*     3.8    15.5    -      -       +      -
    153F  THR*     4.5     4.9    -      -       +      -
    154F  PHE*     3.6    32.5    -      -       +      -
    155F  VAL*     3.8    16.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASP 97 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     74E  ALA*     3.5    25.8    -      -       +      +
     77E  CYS*     3.2    30.5    -      -       -      +
     81E  ARG*     3.0    26.5    +      -       -      -
     93F  LYS*     2.9    18.9    +      -       -      +
     94F  ILE*     3.5     8.1    -      -       +      +
     96F  VAL*     1.3    79.6    -      -       -      +
     98F  ILE*     1.3    64.2    +      -       -      +
    100F  GLU*     3.2    25.0    -      -       -      +
    101F  ASN*     3.2    13.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 98 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     55E  ASP*     3.8    19.5    -      -       +      +
     56E  PHE*     3.4    35.0    -      -       +      -
     68E  LYS      3.8     4.0    -      -       -      +
     69E  ILE*     4.1     0.7    -      -       +      -
     70E  THR*     3.4    40.6    -      -       -      +
     71E  GLN*     4.7     1.2    -      -       -      +
     74E  ALA*     3.9    15.5    -      -       +      -
     94F  ILE*     2.9    39.8    +      -       +      +
     95F  ARG*     4.0     2.2    -      -       -      +
     97F  ASP*     1.3    74.9    -      -       -      +
     99F  LEU*     1.3    65.5    +      -       -      +
    101F  ASN*     4.1     1.7    -      -       -      +
    102F  GLN*     3.0    26.0    +      -       -      +
    140F  PHE*     4.3     9.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 99 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     56E  PHE*     3.6    28.3    -      -       +      -
     95F  ARG      2.8    24.3    +      -       -      +
     96F  VAL      4.1     0.9    -      -       -      +
     98F  ILE*     1.3    72.1    -      -       -      +
    100F  GLU*     1.3    65.9    +      -       -      +
    102F  GLN*     2.8     2.9    +      -       +      -
    103F  ALA*     2.7    36.5    +      -       +      +
    137F  PHE*     3.9    18.2    -      -       +      -
    140F  PHE*     4.0    12.6    -      -       +      -
    147F  PHE*     4.0    23.3    -      -       +      -
    155F  VAL*     3.8    39.0    -      -       +      +
    158F  LEU*     5.4     0.2    -      -       +      -
    159F  ALA*     4.5     9.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 100 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     73E  ASN*     5.1     0.3    +      -       -      -
     77E  CYS*     6.1     0.7    -      -       -      -
    100E  GLU*     4.0    14.4    -      -       -      +
    101E  ASN*     4.5     2.9    +      -       -      +
     73F  ASN*     3.6    32.4    +      -       -      +
     77F  CYS*     4.6     9.8    -      -       -      -
     96F  VAL*     2.8    29.0    +      -       -      +
     97F  ASP*     3.2    15.9    -      -       -      +
     99F  LEU*     1.3    74.1    -      -       -      +
    101F  ASN*     1.3    76.9    +      -       -      +
    103F  ALA*     3.4     4.3    +      -       -      +
    104F  MET*     3.4    20.0    +      -       -      +
    154F  PHE*     4.0    29.5    -      -       +      -
    155F  VAL*     4.4     1.7    -      -       -      +
    158F  LEU*     4.1    14.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 101 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     71E  GLN*     3.2    36.4    -      -       +      +
     72E  SER*     5.4     0.2    -      -       -      -
     73E  ASN*     3.0    41.2    +      -       -      +
     74E  ALA      3.5     4.3    +      -       -      -
     73F  ASN*     4.6     4.0    -      -       -      +
     97F  ASP*     3.2     9.1    +      -       -      +
    100F  GLU*     1.3   102.2    +      -       -      +
    102F  GLN*     1.3    57.2    +      -       -      +
    104F  MET*     3.3    10.4    +      -       -      +
    105F  ASP*     3.0    32.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 102 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     56E  PHE*     3.5    57.0    -      -       +      +
     57E  PRO      5.5     0.8    +      -       -      -
     58E  ASN*     5.1     9.4    +      -       -      +
     70E  THR      4.6     2.4    -      -       -      +
     71E  GLN*     2.8    33.5    +      -       -      +
     98F  ILE      3.0    19.5    +      -       -      +
     99F  LEU*     2.8    10.8    +      -       +      +
    101F  ASN*     1.3    74.1    -      -       -      +
    103F  ALA*     1.3    63.0    +      -       -      +
    105F  ASP*     3.2    11.6    +      -       -      +
    106F  VAL*     2.8    29.8    +      -       +      +
    137F  PHE*     4.2     6.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 103 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     99F  LEU*     2.7    28.2    +      -       +      +
    100F  GLU      3.7     4.5    -      -       -      +
    102F  GLN*     1.3    72.0    -      -       -      +
    104F  MET*     1.3    64.2    +      -       -      +
    106F  VAL*     3.3    13.1    +      -       -      +
    107F  SER*     3.4    15.8    +      -       -      -
    137F  PHE*     4.7     7.0    -      -       +      -
    158F  LEU*     4.0    32.5    -      -       +      -
    159F  ALA*     4.8     1.6    -      -       -      +
    162F  VAL*     3.5    19.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with MET 104 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12F  LEU*     3.6    32.5    -      -       +      -
     72F  SER*     4.0    17.7    -      -       -      +
     73F  ASN*     3.7    36.6    -      -       -      +
    100F  GLU      3.4     7.5    +      -       -      +
    101F  ASN*     3.3    11.9    -      -       -      +
    102F  GLN      3.2     0.2    -      -       -      -
    103F  ALA*     1.3    78.3    -      -       -      +
    105F  ASP*     1.3    58.0    +      -       -      +
    107F  SER*     2.9    10.0    +      -       -      +
    108F  ASN*     2.8    45.5    +      -       -      +
    158F  LEU*     5.0    11.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASP 105 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     71E  GLN*     4.0    20.2    +      -       -      +
    101F  ASN*     3.0    19.3    +      -       -      +
    102F  GLN*     3.2    16.8    +      -       -      +
    104F  MET*     1.3    75.5    -      -       -      +
    106F  VAL*     1.3    57.7    +      -       +      +
    108F  ASN*     3.5    13.4    -      -       -      +
    109F  GLN*     2.9    58.8    +      -       -      +
    112F  ARG*     5.1     5.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 106 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    102F  GLN*     2.8    21.3    -      -       +      +
    103F  ALA*     3.5     6.7    -      -       -      +
    104F  MET      3.2     0.4    -      -       -      -
    105F  ASP*     1.3    74.1    -      -       +      +
    107F  SER*     1.3    60.3    +      -       -      +
    109F  GLN*     4.1    10.2    -      -       -      +
    110F  LEU*     3.5    21.5    +      -       -      +
    126F  TYR*     3.9     8.1    +      -       -      +
    133F  MET*     5.4    12.6    -      -       +      -
    137F  PHE*     3.6    31.4    -      -       +      -
    162F  VAL*     3.7    13.7    -      -       +      -
    166F  HIS*     3.7    26.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with SER 107 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12F  LEU*     4.6    21.2    -      -       -      +
    103F  ALA      3.4    10.7    +      -       -      -
    104F  MET*     2.9    12.9    +      -       -      +
    106F  VAL*     1.3    76.0    -      -       -      +
    108F  ASN*     1.3    61.8    +      -       -      +
    110F  LEU*     3.5     4.0    +      -       -      +
    111F  ALA*     2.8    32.8    +      -       -      +
    161F  ASP*     6.0     1.0    -      -       -      -
    162F  VAL*     3.5    19.7    -      -       -      +
    165F  LEU*     5.7     6.6    -      -       -      +
    166F  HIS*     5.8     0.7    -      -       -      -
    208F  TYR*     4.8     1.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with ASN 108 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    108E  ASN*     5.9     2.6    -      -       -      -
     12F  LEU*     5.9     4.6    -      -       -      +
    104F  MET*     2.8    31.8    +      -       -      +
    105F  ASP*     3.5    15.5    +      -       -      +
    107F  SER*     1.3    75.7    -      -       -      +
    109F  GLN*     1.3    63.5    +      -       -      +
    111F  ALA*     2.9     9.4    +      -       -      +
    112F  ARG*     2.9    53.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 109 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    105F  ASP*     2.9    46.7    +      -       -      +
    106F  VAL*     4.1    11.5    -      -       -      +
    108F  ASN*     1.3    76.6    -      -       -      +
    110F  LEU*     1.3    61.3    +      -       -      +
    112F  ARG*     3.5    25.9    +      -       -      +
    113F  VAL*     3.3    25.8    +      -       -      +
    126F  TYR*     4.8    12.4    -      -       +      -
    133F  MET*     4.0    23.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 110 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    106F  VAL      3.5    15.0    +      -       -      +
    107F  SER*     3.5     5.0    +      -       -      +
    108F  ASN      3.2     0.6    -      -       -      -
    109F  GLN*     1.3    75.4    -      -       -      +
    111F  ALA*     1.3    67.7    +      -       -      +
    113F  VAL*     3.0     7.2    +      -       +      -
    114F  CYS*     2.8    22.1    +      -       -      +
    126F  TYR*     3.3    33.3    +      -       +      +
    165F  LEU*     3.3    33.4    -      -       +      -
    166F  HIS*     3.9    22.9    -      -       +      +
    169F  PHE*     3.8    35.9    -      -       +      -
    208F  TYR*     3.2     9.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 111 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12F  LEU*     5.9     7.0    -      -       +      -
    107F  SER      2.8    20.1    +      -       -      +
    108F  ASN*     2.9     8.9    +      -       -      +
    110F  LEU*     1.3    75.6    -      -       -      +
    112F  ARG*     1.3    63.0    +      -       +      +
    114F  CYS*     2.9     4.2    +      -       -      -
    115F  TYR*     2.8    39.9    +      -       +      -
    208F  TYR*     3.4    25.1    +      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 112 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    108E  ASN*     5.3    11.9    -      -       -      +
    112E  ARG*     4.5    29.7    -      -       -      +
    105F  ASP*     5.1     5.1    +      -       -      -
    108F  ASN*     2.9    42.7    +      -       -      +
    109F  GLN*     3.6    37.9    -      -       -      +
    111F  ALA*     1.3    75.7    -      -       +      +
    113F  VAL*     1.3    57.7    +      -       +      +
    115F  TYR*     2.9     9.3    +      -       -      +
    116F  SER*     2.8    31.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 113 (chain F). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    109F  GLN      3.3    15.0    -      -       -      +
    110F  LEU*     3.0    15.7    +      -       +      +
    112F  ARG*     1.3    78.6    -      -       +      +
    114F  CYS*     1.3    60.8    +      -       -      +
    115F  TYR      3.1     1.1    +      -       -      -
    116F  SER*     3.6    16.2    +      -       -      +
    119F  PHE*     3.7    19.6    -      -       +      -
    122F  LEU*     4.5    15.5    -      -       +      +
    123F  LYS*     4.1    35.2    -      -       +      +
    126F  TYR*     4.4    27.8    -      -       +      -
    169F  PHE*     5.1     1.6    -      -       +      -
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Residues in contact with CYS 114 (chain F). Click here for Legend to table.
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                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
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    110F  LEU*     2.8    13.0    +      -       -      +
    111F  ALA      2.9     8.0    +      -       -      +
    113F  VAL*     1.3    76.9    -      -       -      +
    115F  TYR*     1.3    59.7    +      -       -      +
    119F  PHE*     4.9     1.3    -      -       -      -
    169F  PHE*     3.6    20.4    -      -       -      -
    208F  TYR*     3.7    32.1    -      -       +      -
    212F  ALA*     3.7     5.7    -      -       -      -
    213F  VAL*     2.9    36.0    +      -       -      +
    214F  TRP*     3.4    41.7    -      -       +      +
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Residues in contact with TYR 115 (chain F). Click here for Legend to table.
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                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
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    111F  ALA*     2.8    31.4    +      -       +      +
    112F  ARG*     2.9     8.0    +      -       -      +
    114F  CYS*     1.3    83.8    -      -       -      +
    116F  SER*     1.3    61.3    +      -       -      +
    117F  PRO*     3.6     7.1    -      -       -      +
    208F  TYR*     4.0    20.9    -      +       -      -
    209F  THR*     3.1    31.8    +      -       -      +
    211F  VAL*     3.6    32.2    -      -       +      +
    212F  ALA*     3.9    17.5    -      -       +      -
    213F  VAL*     4.5     5.8    -      -       -      +
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A short description of the analytical approach
The contact analysis used in this page is based upon the approach developed in: Sobolev V., Wade R.C., Vriend G. and Edelman M. PROTEINS (1996) 25, 120-129. Contact legitimacy depends on the hydrophobic-hydrophilic properties of the contacting atoms. In order to define it, for each inter-atomic contact, eight atom classes have been introduced:


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

Legend:
+, legitimate
-, illegitimate
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  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) +   -    +    +   +   +    +    -
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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