Contacts of the helix formed by residues 145 - 169 (chain D) in PDB entry 3BUW


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 SER 145 (chain D).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    139D  ARG*     2.8    32.9    +      -       -      -
    142D  GLU*     2.8    21.6    +      -       -      -
    143D  GLU      3.1     2.6    +      -       -      -
    144D  ASN*     1.3    82.3    -      -       -      +
    146D  GLN*     1.3    59.2    +      -       -      +
    147D  PRO*     3.5     8.4    -      -       -      +
    148D  ARG*     3.2    13.7    +      -       -      +
    149D  ARG*     3.0    26.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 146 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    203B  LYS*     4.6    23.8    -      -       +      +
    139D  ARG*     5.2     7.5    -      -       -      +
    144D  ASN      4.0     0.6    +      -       -      +
    145D  SER*     1.3    69.1    -      -       -      +
    147D  PRO*     1.3    75.5    -      -       +      +
    149D  ARG*     3.1    16.6    +      -       -      +
    150D  ASN*     2.8    45.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with PRO 147 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    132D  LEU*     3.4    19.4    -      -       +      +
    136D  GLY*     4.3    11.9    -      -       -      -
    139D  ARG*     3.5    45.8    -      -       +      +
    140D  MET*     3.4    25.5    -      -       -      +
    145D  SER*     3.5    14.8    -      -       -      +
    146D  GLN*     1.3    92.5    -      -       +      +
    148D  ARG*     1.3    60.0    +      -       -      +
    150D  ASN*     3.4     9.7    +      -       -      +
    151D  LEU*     3.1    17.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 148 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75D  LEU*     2.7    38.6    +      -       -      +
     76D  ALA      4.4     1.8    +      -       -      -
     77D  LEU*     3.6    27.5    -      -       -      +
     78D  LYS*     6.1     2.6    -      -       -      +
    139D  ARG      4.8     0.2    +      -       -      -
    140D  MET*     3.1    30.6    +      -       -      +
    141D  TYR*     4.4    10.3    +      -       -      +
    142D  GLU      4.1     6.1    -      -       -      +
    143D  GLU*     3.6    34.7    +      -       -      +
    144D  ASN      4.9     0.2    -      -       -      +
    145D  SER*     3.2    22.0    +      -       -      +
    146D  GLN      3.1     0.2    -      -       -      -
    147D  PRO*     1.3    80.0    -      -       -      +
    149D  ARG*     1.3    64.3    +      -       -      +
    151D  LEU*     3.1    20.5    +      -       -      +
    152D  THR*     3.0    28.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 149 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    144D  ASN      5.8     1.3    -      -       -      +
    145D  SER      3.0    13.3    +      -       -      +
    146D  GLN*     3.6    24.0    -      -       -      +
    148D  ARG*     1.3    75.3    -      -       -      +
    150D  ASN*     1.3    61.3    +      -       -      +
    152D  THR*     3.1     6.4    +      -       -      -
    153D  LYS*     2.9    65.1    +      -       -      +
    271D  PHE*     3.2    33.6    +      -       -      +
    272D  LEU*     4.6     7.3    -      -       -      +
    276D  GLU*     3.3    25.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with ASN 150 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    132D  LEU*     3.9    20.1    -      -       +      +
    146D  GLN*     2.8    42.6    +      -       -      +
    147D  PRO*     3.5    11.6    -      -       -      +
    148D  ARG      3.2     0.2    -      -       -      -
    149D  ARG*     1.3    80.8    +      -       -      +
    151D  LEU*     1.3    54.6    +      -       -      +
    153D  LYS*     3.3     8.1    +      -       -      +
    154D  LEU*     2.7    43.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 151 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     70D  CYS*     4.2    13.7    -      -       -      -
     75D  LEU*     4.5     4.5    -      -       +      -
     77D  LEU*     4.4    19.1    -      -       +      -
     84D  ILE*     5.5     4.3    -      -       +      -
    129D  THR*     3.9    28.5    -      -       +      -
    132D  LEU*     3.6     9.8    -      -       +      +
    133D  PHE*     4.1    27.1    -      -       +      -
    140D  MET*     4.2     7.2    -      -       +      -
    147D  PRO      3.1    13.4    +      -       -      +
    148D  ARG*     3.1    24.0    +      -       -      +
    150D  ASN*     1.3    76.0    -      -       -      +
    152D  THR*     1.3    59.9    +      -       -      +
    154D  LEU*     3.2     4.9    +      -       +      +
    155D  SER*     2.8    39.1    +      -       -      +
    158D  PHE*     6.4     0.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 152 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     78D  LYS*     5.9     0.7    +      -       -      -
     82D  PRO*     5.5     0.4    -      -       +      -
    148D  ARG*     3.0    19.1    +      -       -      +
    149D  ARG*     3.3    12.4    -      -       -      +
    151D  LEU*     1.3    74.2    -      -       -      +
    153D  LYS*     1.3    60.2    +      -       -      +
    155D  SER*     3.1    14.1    +      -       -      -
    156D  LEU*     2.7    29.5    -      -       +      +
    271D  PHE      5.5     0.2    -      -       -      +
    273D  THR*     3.6    19.3    -      -       +      +
    276D  GLU*     3.5    36.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 153 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    149D  ARG*     2.9    38.6    +      -       -      +
    150D  ASN*     3.7    10.3    -      -       -      +
    152D  THR*     1.3    76.6    -      -       -      +
    154D  LEU*     1.3    69.3    +      -       +      +
    156D  LEU*     3.1    12.0    +      -       -      +
    157D  ILE*     3.0    31.4    +      -       +      +
    232D  CYS*     4.4    10.8    -      -       -      -
    271D  PHE*     2.8    54.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 154 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    125D  LYS*     3.9    31.0    -      -       +      +
    128D  GLN*     3.9    17.7    -      -       +      +
    129D  THR*     3.9    28.0    -      -       -      +
    132D  LEU*     5.3     4.0    -      -       +      -
    150D  ASN*     2.7    37.6    +      -       +      +
    151D  LEU*     3.5    12.3    -      -       +      +
    153D  LYS*     1.3    86.9    -      -       +      +
    155D  SER*     1.3    56.4    +      -       -      +
    157D  ILE*     3.1     9.8    +      -       +      +
    158D  PHE*     2.8    40.9    +      -       +      -
----------------------------------------------------------
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Residues in contact with SER 155 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     82D  PRO*     3.7    25.5    +      -       -      +
     84D  ILE*     3.8    24.4    +      -       -      +
     87D  LEU*     3.5    12.0    -      -       -      +
    151D  LEU*     2.8    24.3    +      -       -      +
    152D  THR*     3.1    12.9    +      -       -      -
    154D  LEU*     1.3    77.1    -      -       -      +
    156D  LEU*     1.3    61.2    +      -       -      +
    158D  PHE*     3.3    10.1    +      -       -      +
    159D  SER      3.0    17.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 156 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     82D  PRO*     3.2    16.8    -      -       +      -
    152D  THR*     2.7    28.9    +      -       +      +
    153D  LYS*     3.1     6.9    +      -       -      +
    155D  SER*     1.3    72.6    -      -       -      +
    157D  ILE*     1.3    65.7    +      -       -      +
    159D  SER*     3.0     4.7    +      -       -      -
    160D  HIS*     2.9    42.1    +      -       +      +
    271D  PHE*     3.3    49.1    -      -       +      +
    272D  LEU      3.7    14.4    -      -       -      +
    273D  THR*     3.0    29.6    -      -       +      -
    297D  CYS*     5.5     5.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 157 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    125D  LYS*     3.9    14.4    -      -       +      -
    153D  LYS*     3.0    27.9    +      -       +      +
    154D  LEU*     3.1    13.9    +      -       +      +
    156D  LEU*     1.3    76.3    -      -       -      +
    158D  PHE*     1.3    57.3    +      -       -      +
    160D  HIS*     3.1     3.4    +      -       -      +
    161D  MET*     2.8    51.9    +      -       +      +
    230D  LEU      2.9    29.8    -      -       -      +
    231D  THR      3.8    21.5    -      -       -      +
    232D  CYS*     3.3    18.8    -      -       +      -
    271D  PHE*     3.2    26.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 158 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     66D  VAL*     5.1     0.7    -      -       +      -
     84D  ILE*     3.2    35.0    -      -       +      -
     87D  LEU*     4.3    10.7    -      -       +      +
     88D  LEU*     3.8    23.1    -      -       +      -
     91D  THR*     4.9     5.3    +      -       +      -
    122D  LEU*     4.0     9.9    -      -       +      -
    125D  LYS*     3.9    25.4    -      -       +      -
    126D  THR*     4.0    17.7    -      -       +      -
    129D  THR*     3.6    28.7    -      -       +      -
    151D  LEU*     6.4     0.4    -      -       +      -
    154D  LEU*     2.8    32.6    +      -       +      -
    155D  SER      3.6     6.5    -      -       -      +
    156D  LEU      3.2     0.2    -      -       -      -
    157D  ILE*     1.3    74.6    -      -       -      +
    159D  SER*     1.3    62.3    +      -       -      +
    161D  MET*     3.0    34.1    +      -       +      +
    162D  LEU*     3.0    23.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 159 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     82D  PRO*     4.1    10.2    -      -       -      +
     87D  LEU*     3.7    28.0    -      -       -      +
    155D  SER      3.0    13.0    +      -       -      -
    156D  LEU*     3.0     9.6    +      -       -      -
    158D  PHE*     1.3    78.1    -      -       -      +
    160D  HIS*     1.3    65.3    +      -       -      +
    162D  LEU*     3.3     3.5    +      -       -      +
    163D  ALA*     3.0    23.3    +      -       -      +
    297D  CYS*     3.8    27.4    +      -       -      +
    300D  LEU*     5.6     0.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with HIS 160 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    156D  LEU*     2.9    34.7    +      -       +      +
    157D  ILE      3.6     5.4    -      -       -      +
    159D  SER*     1.3    78.4    +      -       -      +
    161D  MET*     1.3    57.5    +      -       -      +
    163D  ALA*     3.4     2.8    +      -       -      +
    164D  GLU*     3.0    29.5    +      -       -      +
    230D  LEU*     3.7    48.8    -      -       +      +
    231D  THR*     4.3     3.4    -      -       +      +
    239D  PHE*     4.3     3.5    -      -       +      -
    271D  PHE*     4.3    14.0    -      +       -      -
    295D  LEU*     5.0    10.4    -      -       +      +
    296D  SER      5.0     0.7    -      -       -      -
    297D  CYS*     4.6    19.5    +      -       +      -
    300D  LEU*     3.7    37.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with MET 161 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     91D  THR*     6.5     0.2    -      -       +      -
    118D  PHE*     3.4    29.2    -      -       +      -
    121D  ASN*     3.6    23.1    -      -       -      +
    122D  LEU*     5.2     8.1    -      -       +      -
    125D  LYS*     4.0    11.7    -      -       +      -
    157D  ILE*     2.8    31.9    +      -       +      +
    158D  PHE*     3.0    64.6    -      -       +      +
    159D  SER      3.2     0.2    -      -       -      -
    160D  HIS*     1.3    74.3    -      -       -      +
    162D  LEU*     1.3    60.0    +      -       -      +
    164D  GLU*     3.3     1.6    +      -       -      +
    165D  LEU*     2.9    23.7    +      -       -      +
    231D  THR*     3.8    27.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 162 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     87D  LEU*     4.1    20.9    -      -       +      +
     90D  ASP*     3.8    28.5    -      -       +      +
     91D  THR*     3.7    36.5    +      -       +      +
     94D  HIS*     4.5     5.8    -      -       +      -
    118D  PHE*     5.1     1.5    -      -       -      -
    158D  PHE      3.0    16.7    +      -       -      +
    159D  SER*     3.3     4.2    +      -       -      +
    161D  MET*     1.3    75.9    -      -       -      +
    163D  ALA*     1.3    64.0    +      -       -      +
    165D  LEU*     3.3     7.4    +      -       +      +
    166D  LYS*     3.0    57.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 163 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    159D  SER*     3.0    15.4    +      -       -      +
    160D  HIS      3.6     1.1    -      -       -      +
    162D  LEU*     1.3    79.1    -      -       -      +
    164D  GLU*     1.3    56.8    +      -       -      +
    166D  LYS*     3.5     5.3    +      -       -      +
    167D  GLY      3.0    23.0    +      -       -      -
    239D  PHE*     3.5    13.5    -      -       +      -
    297D  CYS      5.8     1.6    -      -       -      +
    300D  LEU*     3.4    34.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 164 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    114D  TYR*     2.6    35.8    +      -       +      +
    118D  PHE*     3.9    10.4    -      -       -      -
    160D  HIS      3.0    17.9    +      -       -      +
    161D  MET*     3.5     3.6    -      -       -      +
    163D  ALA*     1.3    74.9    -      -       -      +
    165D  LEU*     1.3    59.4    +      -       -      +
    167D  GLY*     3.1     1.7    +      -       -      -
    168D  ILE*     2.9    35.4    +      -       +      +
    199D  ILE*     5.8     0.5    -      -       -      +
    231D  THR*     3.9    17.3    +      -       +      +
    233D  ASN*     5.5     4.2    +      -       -      -
    237D  SER*     2.7    27.9    +      -       -      +
    239D  PHE*     3.5    30.1    -      -       +      -
    240D  GLU*     3.7    16.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 165 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     91D  THR*     4.6     7.9    -      -       +      -
     94D  HIS*     3.7    29.6    -      -       +      +
     95D  LEU*     4.1    19.7    -      -       +      -
     98D  ILE*     4.0    16.2    -      -       +      -
    114D  TYR*     3.5    10.7    +      -       +      +
    115D  PHE*     4.8     2.7    -      -       +      -
    118D  PHE*     3.9    42.8    -      -       +      -
    161D  MET      2.9    17.6    +      -       -      +
    162D  LEU*     3.3     7.6    +      -       +      +
    164D  GLU*     1.3    76.3    -      -       -      +
    166D  LYS*     1.3    56.6    +      -       -      +
    168D  ILE      3.8     0.2    -      -       -      -
    169D  PHE*     2.8    47.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 166 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     90D  ASP*     4.9    11.4    +      -       -      +
     94D  HIS*     3.7    40.8    -      -       +      +
    162D  LEU*     3.0    49.9    +      -       +      +
    163D  ALA*     4.0     6.3    -      -       -      +
    165D  LEU*     1.3    75.8    -      -       -      +
    167D  GLY*     1.3    61.1    +      -       -      +
    170D  PRO*     3.3    26.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 167 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    163D  ALA      3.0    15.5    +      -       -      -
    164D  GLU      3.1     4.2    +      -       -      -
    166D  LYS*     1.3    79.2    -      -       -      +
    168D  ILE*     1.3    63.5    +      -       -      +
    170D  PRO*     3.6     9.9    -      -       -      +
    175D  GLN*     5.3     2.1    -      -       -      +
    179D  PHE*     3.8    19.2    -      -       -      -
    239D  PHE*     4.4    13.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 168 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    114D  TYR*     3.6    35.2    -      -       +      -
    164D  GLU*     2.9    20.7    +      -       +      +
    165D  LEU      4.1     0.7    -      -       -      +
    167D  GLY*     1.3    76.7    -      -       -      +
    169D  PHE*     1.3    53.4    +      -       +      +
    170D  PRO*     3.2     8.1    -      -       -      +
    174D  PHE*     3.4    32.9    -      -       +      -
    175D  GLN*     2.8    31.7    +      -       -      -
    176D  GLY*     3.6    10.3    +      -       -      +
    179D  PHE*     3.9    23.6    -      -       +      -
    198D  THR*     3.9    18.4    -      -       +      -
    237D  SER*     5.7     0.7    -      -       -      +
    238D  VAL*     3.9    10.8    -      -       +      -
    239D  PHE*     4.2     8.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 169 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     94D  HIS*     3.0    13.0    -      -       +      -
     98D  ILE*     3.6    28.3    -      -       +      -
    102D  TYR*     4.0     3.4    -      +       -      -
    109D  LEU*     3.9    30.1    -      -       +      -
    112D  ASN*     4.6     2.9    -      -       -      -
    114D  TYR*     3.7    25.6    -      +       -      -
    115D  PHE*     4.0    21.3    -      +       +      -
    165D  LEU*     2.8    23.6    +      -       +      +
    166D  LYS      3.6     3.8    -      -       -      -
    168D  ILE*     1.3    83.1    -      -       +      +
    170D  PRO*     1.3    64.8    -      -       -      +
    172D  GLY      2.9    23.7    +      -       -      -
    173D  LEU      3.4     4.0    -      -       -      -
    174D  PHE*     3.3    47.6    -      +       +      -
----------------------------------------------------------
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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