Contacts of the helix formed by residues 131 - 154 (chain J) in PDB entry 2YW7


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 ASP 131 (chain J).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    121E  ARG*     3.7    12.7    +      -       -      +
     13J  LYS*     6.0     0.2    -      -       +      -
     17J  VAL*     4.0    20.9    -      -       +      +
     71J  ARG*     2.8    24.6    +      -       -      -
     75J  LEU*     3.6    17.7    -      -       -      +
    127J  LEU*     3.2    15.0    +      -       +      +
    130J  LEU*     1.3    81.2    -      -       -      +
    132J  LEU*     1.3    63.6    +      -       -      +
    133J  VAL*     2.9     6.2    +      -       -      +
    134J  SER*     2.6    41.2    +      -       -      -
    135J  GLN*     3.3    17.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 132 (chain J). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    121E  ARG*     4.5     4.4    -      -       -      +
    124E  ILE*     4.9    10.3    -      -       +      -
    125E  GLU*     5.5     7.9    -      -       +      -
    128E  GLU*     4.0    24.2    -      -       -      +
    135E  GLN*     4.1    13.0    -      -       -      +
    139E  ILE*     3.7    32.5    -      -       +      +
    127J  LEU      4.9     0.2    -      -       -      -
    128J  GLU*     3.9    29.8    -      -       -      +
    129J  ASP      5.7     1.3    -      -       -      -
    130J  LEU      5.5     1.8    -      -       -      +
    131J  ASP*     1.3    73.0    -      -       -      +
    133J  VAL*     1.3    61.2    +      -       +      +
    135J  GLN*     3.6    22.6    -      -       -      +
    136J  ASP*     2.9    30.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 133 (chain J). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    121E  ARG*     3.6    23.6    -      -       -      +
    124E  ILE*     4.9     6.5    -      -       +      -
    139E  ILE*     4.4     9.6    -      -       +      +
    142E  ALA*     4.0    18.8    -      -       +      -
    143E  GLY*     3.7    22.9    -      -       -      -
    146E  GLU*     4.0     7.9    -      -       -      +
     71J  ARG*     3.3    31.4    -      -       -      +
    131J  ASP*     2.9     6.2    +      -       -      +
    132J  LEU*     1.3    80.3    -      -       -      +
    134J  SER*     1.3    64.1    -      -       -      +
    135J  GLN      3.0     0.9    +      -       -      -
    136J  ASP*     3.2    12.1    +      -       -      +
    137J  LEU*     3.3    12.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with SER 134 (chain J). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     17J  VAL*     4.6     0.2    -      -       -      -
     21J  LEU*     3.5    28.5    -      -       -      +
     71J  ARG*     3.0    31.2    +      -       -      +
     75J  LEU*     3.8     0.5    -      -       -      +
    127J  LEU*     4.2    11.2    -      -       -      -
    131J  ASP*     2.6    31.4    +      -       -      -
    133J  VAL*     1.3    72.2    -      -       -      +
    135J  GLN*     1.3    56.5    +      -       -      +
    137J  LEU*     3.2    12.6    -      -       -      +
    138J  LEU*     3.1    27.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 135 (chain J). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    132C  LEU*     4.2     4.9    -      -       -      +
    124J  ILE*     3.1    37.9    +      -       +      +
    127J  LEU*     4.0    14.8    -      -       +      +
    128J  GLU*     2.8    44.6    +      -       -      +
    131J  ASP      3.3    12.4    +      -       -      +
    132J  LEU*     3.6    22.3    -      -       -      +
    133J  VAL      3.1     0.6    -      -       -      -
    134J  SER*     1.3    73.8    -      -       -      +
    136J  ASP*     1.3    53.8    +      -       -      +
    137J  LEU      2.9     4.0    -      -       -      -
    138J  LEU*     2.7     8.4    +      -       -      +
    139J  ILE*     2.7    49.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with ASP 136 (chain J). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    136C  ASP*     3.4    23.9    -      -       -      +
    136E  ASP*     4.6     2.2    -      -       -      +
    139E  ILE*     3.5    31.1    -      -       +      +
    140E  ALA*     4.6     8.5    -      -       -      +
    132J  LEU      2.9    20.4    +      -       -      +
    133J  VAL*     3.7     5.2    -      -       -      +
    135J  GLN*     1.3    74.8    +      -       -      +
    137J  LEU*     1.3    58.9    +      -       -      +
    139J  ILE*     3.6    10.1    -      -       -      +
    140J  ALA*     3.3    19.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 137 (chain J). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     21J  LEU*     5.4     0.9    -      -       +      -
     67J  GLU*     2.9    32.8    -      -       +      +
     68J  VAL*     4.3    20.2    -      -       +      +
     71J  ARG*     4.0    33.0    -      -       +      -
    133J  VAL*     3.3    10.6    +      -       +      +
    134J  SER*     3.2    12.3    -      -       -      +
    135J  GLN      2.9     0.8    -      -       -      -
    136J  ASP*     1.3    77.1    -      -       -      +
    138J  LEU*     1.3    64.3    +      -       +      +
    140J  ALA*     3.5    14.4    -      -       +      +
    141J  HIS*     3.4    24.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 138 (chain J). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     20J  LEU*     6.1     0.2    -      -       +      -
     21J  LEU*     4.6     7.6    -      -       +      -
     24J  GLN*     3.7    32.8    -      -       +      +
     28J  TYR*     4.2     2.0    -      -       -      +
     68J  VAL*     4.5    12.3    -      -       +      -
    120J  THR*     4.4     4.9    -      -       +      +
    123J  SER*     3.5    36.8    -      -       -      +
    124J  ILE*     3.7    16.8    -      -       +      +
    127J  LEU*     3.9    17.9    -      -       +      -
    134J  SER      3.1    14.3    +      -       -      +
    135J  GLN*     2.7    12.9    +      -       -      +
    137J  LEU*     1.3    69.7    -      -       +      +
    139J  ILE*     1.3    55.6    +      -       -      +
    140J  ALA      2.8     3.1    +      -       -      -
    141J  HIS*     2.9    18.7    +      -       +      +
    142J  ALA*     2.7    33.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 139 (chain J). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    132C  LEU*     3.8    19.5    -      -       +      +
    133C  VAL*     3.7    37.3    -      -       +      +
    136C  ASP*     3.9    33.9    -      -       +      +
    124J  ILE*     3.5    23.4    -      -       +      +
    135J  GLN*     2.7    38.5    +      -       +      +
    136J  ASP*     3.6    12.8    -      -       -      +
    138J  LEU*     1.3    71.3    -      -       -      +
    140J  ALA*     1.3    63.4    +      -       -      +
    142J  ALA*     3.4     1.7    -      -       -      +
    143J  GLY*     3.3    14.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 140 (chain J). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     64J  TYR*     5.7     0.2    -      -       -      -
    136J  ASP      3.3    12.0    +      -       -      +
    137J  LEU*     3.5    15.3    -      -       +      +
    138J  LEU      2.8     1.4    +      -       -      -
    139J  ILE*     1.3    80.6    -      -       -      +
    141J  HIS*     1.3    71.8    +      -       +      +
    142J  ALA      3.1     1.4    +      -       -      -
    143J  GLY*     3.2     1.2    +      -       -      -
    144J  GLU*     3.2    23.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 141 (chain J). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     28J  TYR*     3.2    31.3    +      +       +      +
     64J  TYR*     3.0    73.1    -      +       +      +
     67J  GLU*     3.4    20.3    +      -       +      -
     68J  VAL*     4.9     2.5    -      -       +      -
    137J  LEU*     3.4    33.9    +      -       +      +
    138J  LEU*     2.9    13.9    +      -       +      +
    140J  ALA*     1.3    77.0    -      -       +      +
    142J  ALA*     1.3    68.6    -      -       -      +
    144J  GLU*     3.3     1.1    +      -       -      +
    145J  LEU*     2.7    28.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 142 (chain J). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    133C  VAL*     3.7    13.0    -      -       +      -
    117J  ILE*     6.2     0.7    -      -       -      +
    120J  THR*     4.4    14.4    -      -       +      +
    121J  ARG*     5.5     2.2    -      -       +      +
    124J  ILE*     3.7    22.0    -      -       +      -
    138J  LEU      2.7    20.3    +      -       -      +
    139J  ILE      3.4     7.9    -      -       -      +
    140J  ALA      3.1     0.2    -      -       -      -
    141J  HIS*     1.3    78.3    -      -       -      +
    143J  GLY*     1.3    56.8    +      -       -      +
    145J  LEU*     2.7    22.3    +      -       -      +
    146J  GLU*     3.0    22.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 143 (chain J). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     71C  ARG*     4.5    11.8    +      -       -      -
    133C  VAL*     3.4    22.7    -      -       -      +
    139J  ILE      3.3     4.0    +      -       -      -
    140J  ALA      3.2     5.8    +      -       -      -
    142J  ALA*     1.3    78.3    -      -       -      +
    144J  GLU*     1.3    59.3    +      -       -      +
    146J  GLU*     3.9     4.8    +      -       -      +
    147J  LYS*     3.3    30.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 144 (chain J). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     57J  GLN*     5.0     3.5    -      -       -      +
     60J  LEU*     4.6    19.4    -      -       +      +
     64J  TYR*     3.2    28.1    +      -       +      +
    140J  ALA      3.2    12.3    +      -       -      +
    141J  HIS      3.7     6.1    -      -       -      +
    142J  ALA      2.8     5.1    +      -       -      -
    143J  GLY*     1.3    72.3    -      -       -      +
    145J  LEU*     1.3    65.2    +      -       -      +
    147J  LYS*     3.1    51.6    +      -       -      +
    148J  PHE*     3.3     5.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 145 (chain J). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     28J  TYR*     4.3    14.8    -      -       +      +
     31J  LEU*     5.1     1.8    -      -       +      -
     57J  GLN*     4.0    21.1    -      -       -      +
     61J  VAL*     4.8     6.1    -      -       +      -
     64J  TYR*     3.7    28.7    -      -       +      -
    113J  TYR*     4.1    11.7    -      -       +      -
    116J  VAL*     3.8    28.5    -      -       +      -
    117J  ILE*     4.1    17.7    -      -       +      +
    120J  THR*     3.9    16.6    -      -       +      +
    141J  HIS      2.7    27.9    +      -       -      +
    142J  ALA*     2.7    10.0    +      -       -      +
    144J  GLU*     1.3    71.1    -      -       -      +
    146J  GLU*     1.3    58.4    +      -       -      +
    148J  PHE*     2.8    22.7    +      -       -      +
    149J  GLN      3.0     8.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 146 (chain J). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     71C  ARG*     3.0    24.0    +      -       -      +
     74C  THR*     3.2    22.7    -      -       +      +
     75C  LEU*     4.1     3.5    -      -       -      +
    133C  VAL*     4.3    10.7    -      -       -      +
    117J  ILE*     3.7    19.7    -      -       +      -
    121J  ARG*     2.7    54.4    +      -       -      +
    142J  ALA*     3.0    18.1    +      -       -      +
    143J  GLY*     4.0     5.6    -      -       -      +
    145J  LEU*     1.3    75.6    -      -       -      +
    147J  LYS*     1.3    62.0    +      -       -      +
    149J  GLN*     3.0    25.1    +      -       +      +
    150J  TRP      3.1     5.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 147 (chain J). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     70C  GLU*     4.2    26.5    +      -       +      +
     71C  ARG*     5.9     1.1    -      -       -      +
     74C  THR*     4.1    15.7    -      -       +      +
    143J  GLY      3.3    17.7    +      -       -      +
    144J  GLU*     3.1    38.5    +      -       -      +
    146J  GLU*     1.3    76.6    -      -       -      +
    148J  PHE*     1.3    52.6    +      -       -      +
    149J  GLN      3.0     0.9    +      -       -      -
    150J  TRP*     3.1     7.8    +      -       +      +
    151J  PHE*     2.7    37.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 148 (chain J). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     35J  LEU*     4.4     8.7    -      -       +      -
     53J  MET*     3.2    52.9    -      -       +      -
     54J  ILE*     4.5    12.1    -      -       +      -
     57J  GLN*     3.4    39.5    -      -       +      +
    109J  LEU*     5.1     2.9    -      -       +      -
    113J  TYR*     3.2    39.6    -      +       +      -
    144J  GLU      3.3     3.4    +      -       -      +
    145J  LEU      2.8    13.9    +      -       -      +
    147J  LYS*     1.3    71.3    -      -       -      +
    149J  GLN*     1.3    66.4    +      -       -      +
    151J  PHE*     3.7    18.8    -      +       +      -
    152J  VAL*     3.0    39.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 149 (chain J). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     74C  THR*     5.3     1.1    -      -       +      -
    110J  ASP*     2.7    30.6    +      -       -      +
    113J  TYR*     3.9    13.4    -      -       +      -
    114J  ASN*     2.9    25.4    +      -       -      +
    117J  ILE*     3.7    31.8    -      -       +      +
    145J  LEU      3.0     5.7    +      -       -      -
    146J  GLU*     3.0    15.5    -      -       +      +
    148J  PHE*     1.3    73.2    -      -       -      +
    150J  TRP*     1.3    68.8    +      -       -      +
    152J  VAL*     2.8     8.3    +      -       -      +
    153J  ARG*     2.7    59.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with TRP 150 (chain J). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     70C  GLU*     5.8     1.1    -      -       +      -
     73C  ALA*     3.3    22.8    +      -       +      +
     74C  THR*     3.9    28.6    -      -       +      +
     40F  TRP      4.4    16.6    -      -       -      -
     42F  VAL      4.6     3.6    -      -       -      -
     43F  VAL*     3.9    18.4    -      -       +      +
     47F  PHE*     3.9    31.2    -      +       -      -
     51F  HIS*     4.8     9.4    -      +       -      -
     99F  ARG*     3.0    46.4    -      -       +      +
    146J  GLU      3.1     2.0    +      -       -      -
    147J  LYS*     3.5     9.0    -      -       +      +
    149J  GLN*     1.3    77.8    -      -       -      +
    151J  PHE*     1.3    83.0    +      +       +      +
    153J  ARG*     3.2    14.8    +      -       +      +
    154J  ALA*     2.6    46.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 151 (chain J). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     47F  PHE*     3.8    27.6    -      +       -      -
     48F  ILE*     4.5    12.8    -      -       +      -
     53J  MET*     4.0    22.2    -      -       +      -
    147J  LYS*     2.7    21.3    +      -       +      +
    148J  PHE*     3.6    26.9    -      +       +      +
    149J  GLN      2.9     0.2    +      -       -      -
    150J  TRP*     1.3    86.1    -      +       +      +
    152J  VAL*     1.3    56.3    -      -       -      +
    154J  ALA*     2.9    14.6    +      -       -      +
    155J  HIS*     2.7    52.0    +      +       +      -
----------------------------------------------------------
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Residues in contact with VAL 152 (chain J). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     53J  MET*     4.2     4.3    -      -       -      -
    106J  LEU*     3.2    44.3    -      -       +      +
    109J  LEU*     4.9     8.5    -      -       +      -
    110J  ASP*     4.4    15.3    -      -       +      +
    113J  TYR*     6.1     1.1    -      -       +      -
    148J  PHE*     3.0    47.0    +      -       +      +
    149J  GLN*     2.8     9.1    +      -       -      +
    151J  PHE*     1.3    74.3    -      -       -      +
    153J  ARG*     1.3    64.9    -      -       -      +
    155J  HIS*     2.8    34.7    +      -       +      +
    156J  LEU*     4.1     2.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 153 (chain J). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     74C  THR      4.9    10.9    +      -       -      -
     76C  GLY*     6.0     2.6    -      -       -      +
     99F  ARG*     6.0     3.6    -      -       -      +
    110J  ASP*     3.6    25.8    +      -       -      +
    114J  ASN*     3.1    22.2    +      -       -      +
    149J  GLN*     2.7    54.4    +      -       -      +
    150J  TRP*     3.4    15.7    -      -       +      +
    152J  VAL*     1.3    74.9    -      -       -      +
    154J  ALA*     1.3    57.8    +      -       +      +
    155J  HIS      3.6     0.7    +      -       -      -
    156J  LEU*     3.6    17.3    +      -       -      +
    157J  GLU      5.0     0.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 154 (chain J). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     43F  VAL*     4.0    28.9    -      -       +      -
     44F  GLY*     2.8    35.3    +      -       -      +
     47F  PHE*     4.1     6.3    -      -       +      -
     99F  ARG*     5.4     2.7    -      -       -      +
    150J  TRP*     2.6    39.4    +      -       +      +
    151J  PHE*     2.9     6.7    +      -       -      +
    152J  VAL      2.9     0.2    +      -       -      -
    153J  ARG*     1.3    72.4    -      -       +      +
    155J  HIS*     1.3    52.0    +      -       -      +
    156J  LEU      3.3     2.0    -      -       -      -
    157J  GLU      4.1     4.1    -      -       -      +
----------------------------------------------------------
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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