Contacts of the helix formed by residues 171 - 195 (chain B) in PDB entry 4P9U


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 LYS 171 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    167B  LYS      4.6     2.9    +      -       -      +
    168B  ASP*     2.3    31.3    +      -       -      +
    170B  LEU*     1.3    68.6    -      -       -      +
    172B  ARG*     1.3    57.6    +      -       -      -
    173B  GLN      3.2     0.7    -      -       -      -
    174B  GLU*     3.1    52.1    +      -       +      +
    175B  ILE*     2.9    36.6    +      -       +      +
    221B  SER*     4.3    19.3    +      -       -      +
    223B  PRO*     6.2     0.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 172 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    158B  GLN*     2.9    56.4    +      -       -      +
    159B  GLN*     5.7     0.6    -      -       -      +
    160B  HIS*     4.0    18.2    +      -       +      +
    168B  ASP*     2.3    49.7    +      -       -      +
    169B  GLU*     4.2    17.5    +      -       -      +
    171B  LYS*     1.3    70.8    -      -       -      +
    173B  GLN*     1.3    63.3    +      -       +      +
    176B  LEU*     2.9    32.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 173 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    142B  PRO*     3.0    41.6    -      -       +      +
    143B  SER*     3.3    26.0    +      -       -      +
    169B  GLU*     3.0    38.3    +      -       +      +
    170B  LEU*     3.9    15.0    -      -       -      +
    171B  LYS      3.2     0.2    -      -       -      -
    172B  ARG*     1.3    81.4    -      -       +      +
    174B  GLU*     1.3    53.2    -      -       -      +
    176B  LEU*     3.2    17.1    -      -       +      +
    177B  ILE*     2.8    36.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 174 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    142B  PRO*     4.4    15.8    -      -       -      +
    170B  LEU      3.0    25.7    -      -       -      +
    171B  LYS*     3.1    55.2    +      -       +      +
    173B  GLN*     1.3    72.9    -      -       -      +
    175B  ILE*     1.3    56.7    +      -       -      +
    176B  LEU      3.0     1.1    -      -       -      -
    177B  ILE*     3.0    27.9    +      -       -      +
    178B  ALA*     2.9    27.0    +      -       -      +
    221B  SER*     5.0     5.0    -      -       -      -
    226B  ARG*     5.2     7.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 175 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    158B  GLN*     3.1    35.2    -      -       -      +
    160B  HIS*     4.9     8.5    -      -       +      +
    168B  ASP*     4.5     8.1    -      -       -      +
    171B  LYS*     2.9    32.8    +      -       +      +
    174B  GLU*     1.3    75.1    -      -       -      +
    176B  LEU*     1.3    58.4    +      -       -      +
    178B  ALA*     3.4     7.1    +      -       -      +
    179B  LYS*     2.9    47.1    +      -       +      +
    217B  SER*     4.8     9.9    -      -       -      +
    221B  SER*     5.7     4.3    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 176 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    143B  SER*     6.3     2.2    -      -       -      -
    156B  LYS      3.8    21.5    -      -       -      +
    158B  GLN*     3.5    27.8    -      -       +      +
    172B  ARG*     2.9    46.7    +      -       -      +
    173B  GLN*     3.2    24.2    -      -       +      +
    174B  GLU      3.0     0.2    -      -       -      -
    175B  ILE*     1.3    76.6    -      -       -      +
    177B  ILE*     1.3    57.2    +      -       -      +
    179B  LYS*     3.6    11.8    -      -       +      +
    180B  THR*     2.9    31.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 177 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    137B  ALA*     4.7    21.5    -      -       +      +
    138B  LEU*     5.8     4.0    -      -       +      -
    142B  PRO*     4.4    25.4    -      -       +      +
    144B  TRP*     6.1     0.7    -      -       +      -
    173B  GLN      2.8    22.0    +      -       -      +
    174B  GLU*     3.0    34.7    +      -       -      +
    176B  LEU*     1.3    69.9    -      -       -      +
    178B  ALA*     1.3    59.7    +      -       -      +
    180B  THR*     3.1    12.3    -      -       +      +
    181B  PHE*     2.9    30.4    +      -       +      +
    226B  ARG*     3.5    38.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 178 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    174B  GLU      2.9    11.0    +      -       -      +
    175B  ILE*     3.4    10.1    -      -       -      +
    177B  ILE*     1.3    77.4    -      -       -      +
    179B  LYS*     1.3    56.7    +      -       -      +
    182B  ASN*     2.9    31.6    +      -       -      +
    216B  GLY      4.1     0.2    -      -       -      +
    217B  SER*     3.2    26.7    -      -       -      +
    220B  PHE*     3.2    35.2    +      -       -      +
    221B  SER*     3.6     8.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 179 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    155B  GLU      5.2     8.7    -      -       -      +
    156B  LYS*     5.6     2.5    -      -       -      -
    157B  ILE      3.1    26.4    +      -       -      +
    158B  GLN*     3.5    17.6    -      -       -      +
    175B  ILE*     2.9    39.6    +      -       +      +
    176B  LEU*     3.6    21.1    -      -       +      +
    178B  ALA*     1.3    77.6    -      -       -      +
    180B  THR*     1.3    56.9    +      -       -      +
    182B  ASN*     3.7     8.7    +      -       -      +
    183B  PHE*     2.9    26.9    +      -       -      +
    217B  SER*     4.0    24.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 180 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    137B  ALA*     4.5    11.2    -      -       +      -
    144B  TRP*     3.7    36.9    -      -       -      +
    153B  TYR*     5.6     2.4    -      -       -      -
    176B  LEU      2.9    18.0    +      -       -      +
    177B  ILE*     3.1    22.7    -      -       +      +
    179B  LYS*     1.3    73.7    -      -       -      +
    181B  PHE*     1.3    60.8    +      -       +      +
    183B  PHE*     3.2    11.0    -      -       -      +
    184B  TYR*     3.0    40.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with PHE 181 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    135B  CYS*     3.7    29.6    -      -       +      -
    137B  ALA*     6.3     3.1    -      -       +      -
    138B  LEU*     4.5     5.4    -      -       +      -
    177B  ILE*     2.9    19.1    +      -       +      +
    178B  ALA      3.9     2.5    -      -       -      +
    180B  THR*     1.3    79.0    -      -       +      +
    182B  ASN*     1.3    57.8    +      -       -      +
    184B  TYR*     3.3     6.0    +      -       -      +
    185B  ASP*     2.9    23.7    +      -       -      +
    220B  PHE*     3.4    27.8    -      +       +      -
    226B  ARG*     3.3    50.5    -      -       +      -
    229B  ALA*     3.5    23.6    -      -       +      -
    230B  MET*     3.6    22.0    -      -       +      -
    233B  TYR*     3.8    11.2    -      +       -      -
----------------------------------------------------------
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Residues in contact with ASN 182 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    178B  ALA      2.9    18.8    +      -       -      +
    179B  LYS*     3.7     6.3    +      -       -      +
    181B  PHE*     1.3    74.5    -      -       -      +
    183B  PHE*     1.3    67.7    +      -       -      +
    185B  ASP*     3.5     0.7    -      -       -      +
    186B  TYR*     2.9    23.7    +      -       -      +
    212B  TYR*     3.1    30.1    -      -       -      +
    213B  ASP*     3.1    36.4    +      -       -      +
    216B  GLY*     3.2    28.0    -      -       -      -
    217B  SER*     4.1     4.7    +      -       -      +
    220B  PHE*     3.5    12.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 183 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    152B  PRO      5.1     2.2    -      -       -      -
    153B  TYR*     3.7    33.2    -      +       -      -
    155B  GLU*     4.0    42.8    -      -       +      -
    179B  LYS      2.9    16.7    +      -       -      +
    180B  THR*     3.2    13.5    -      -       -      +
    182B  ASN*     1.3    80.1    -      -       -      +
    184B  TYR*     1.3    78.9    +      +       -      +
    186B  TYR*     3.5     7.4    +      +       -      +
    187B  MET*     2.9    58.3    +      -       +      +
    209B  LYS*     5.9     3.4    -      -       -      -
    213B  ASP*     5.5     1.1    -      -       -      -
----------------------------------------------------------
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Residues in contact with TYR 184 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    130B  ASN*     4.5     7.6    -      -       -      -
    131B  VAL*     3.8    20.7    -      -       +      +
    134B  SER*     3.4    46.4    +      -       -      -
    135B  CYS*     3.8    24.7    -      -       -      -
    144B  TRP*     4.0     8.0    -      +       -      -
    148B  ILE*     4.4     5.0    -      -       -      +
    153B  TYR*     2.6    28.3    +      +       -      -
    180B  THR*     3.0    42.6    +      -       -      +
    181B  PHE*     3.9     0.9    -      -       -      +
    183B  PHE*     1.3    85.3    -      +       -      +
    185B  ASP*     1.3    61.3    +      -       -      +
    187B  MET*     3.5    28.8    -      -       +      +
    188B  LEU*     2.9    28.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 185 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    105B  ARG*     3.7     3.5    +      -       -      -
    181B  PHE      2.9    16.7    +      -       -      +
    182B  ASN      3.3     5.6    +      -       -      +
    184B  TYR*     1.3    75.6    -      -       -      +
    186B  TYR*     1.3    62.0    +      -       -      +
    188B  LEU*     3.1     6.1    +      -       -      +
    189B  PHE*     3.0    37.0    +      -       -      -
    212B  TYR*     2.4    39.4    +      -       +      -
    220B  PHE*     3.4    29.1    -      -       +      -
    233B  TYR*     2.6    34.1    +      -       -      +
    255B  TYR*     4.2     6.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with TYR 186 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    182B  ASN      2.9    15.9    +      -       -      +
    183B  PHE*     3.8     7.0    -      +       -      +
    185B  ASP*     1.3    74.0    +      -       -      +
    187B  MET*     1.3    72.6    +      -       +      +
    189B  PHE*     4.1     0.8    -      -       -      +
    190B  GLN*     2.9    45.9    +      -       +      +
    205B  PHE*     3.3    42.3    +      +       +      -
    206B  ASN*     3.4    23.6    +      -       -      -
    209B  LYS*     3.4    47.9    -      -       +      +
    212B  TYR*     3.8    35.9    -      +       +      -
    213B  ASP*     4.4     8.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with MET 187 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    127B  ILE*     5.7     0.7    -      -       +      +
    130B  ASN*     4.2    18.4    -      -       -      +
    131B  VAL*     4.5     8.5    -      -       +      -
    183B  PHE*     2.9    49.6    +      -       +      +
    184B  TYR*     3.5    24.0    -      -       +      +
    185B  ASP      3.3     0.2    -      -       -      -
    186B  TYR*     1.3    81.6    -      -       +      +
    188B  LEU*     1.3    65.0    +      -       -      +
    190B  GLN*     4.9     1.6    -      -       -      -
    191B  ARG*     2.9    77.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 188 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    113B  MET*     4.4     6.7    -      -       +      -
    127B  ILE*     6.0     2.5    -      -       -      -
    128B  MET*     4.5    20.6    -      -       +      -
    131B  VAL*     3.7    30.7    -      -       +      +
    184B  TYR      2.9    14.2    +      -       -      +
    185B  ASP*     3.3     9.9    -      -       -      +
    187B  MET*     1.3    75.2    -      -       -      +
    189B  PHE*     1.3    85.2    +      -       +      +
    191B  ARG*     4.2     1.5    -      -       -      +
    192B  LEU*     2.9    51.5    +      -       +      +
    233B  TYR*     3.7    36.3    -      -       +      -
    236B  LEU*     4.4     6.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 189 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    105B  ARG*     3.6    32.5    -      -       +      -
    109B  SER*     3.6    22.4    -      -       -      -
    112B  PHE*     3.8    10.2    -      +       -      -
    113B  MET*     3.6    19.5    -      -       +      -
    185B  ASP*     3.0    33.9    +      -       -      +
    186B  TYR      4.1     2.2    -      -       -      +
    188B  LEU*     1.3    88.7    -      -       +      +
    190B  GLN*     1.3    57.8    +      -       -      +
    192B  LEU*     4.6     2.5    -      -       -      -
    193B  ALA*     2.9    28.8    +      -       -      +
    205B  PHE*     3.6    23.3    -      +       +      -
    212B  TYR*     3.2    23.8    -      -       +      +
    232B  PHE*     3.9    25.4    -      +       -      -
    233B  TYR*     4.9     2.2    -      +       -      -
    252B  ILE*     6.3     0.2    -      -       +      -
    255B  TYR*     4.6     5.2    -      +       -      -
----------------------------------------------------------
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Residues in contact with GLN 190 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     76A  GLU*     3.1    26.4    +      -       -      +
    186B  TYR*     2.9    47.5    +      -       +      +
    187B  MET*     4.3     1.6    -      -       -      +
    189B  PHE*     1.3    75.3    -      -       -      +
    191B  ARG*     1.3    84.1    +      -       -      +
    193B  ALA*     2.9    21.7    +      -       -      +
    194B  PHE*     3.0    26.7    +      -       +      -
    202B  GLY      4.2     7.0    -      -       -      +
    205B  PHE*     3.8    18.8    -      -       +      -
    206B  ASN*     2.9    31.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 191 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     76A  GLU*     5.5     5.6    +      -       -      +
    127B  ILE*     3.6    35.5    -      -       +      +
    131B  VAL*     6.0     0.7    -      -       -      -
    187B  MET*     2.9    64.9    +      -       -      +
    188B  LEU*     4.2     0.9    -      -       -      +
    190B  GLN*     1.3    89.7    +      -       -      +
    192B  LEU*     1.3    61.3    +      -       -      +
    194B  PHE*     3.3     5.3    +      -       -      +
    195B  HIS*     2.8    38.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 192 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    112B  PHE*     3.6    14.4    -      -       +      -
    113B  MET*     4.1    20.2    -      -       +      -
    116B  ALA*     3.5    27.6    -      -       +      +
    117B  PHE*     4.2    10.8    -      -       +      -
    124B  ALA*     3.8    25.8    -      -       +      -
    127B  ILE*     3.8    19.7    -      -       +      -
    128B  MET*     4.0    26.9    -      -       +      -
    188B  LEU*     2.9    42.3    +      -       +      +
    189B  PHE*     3.9     3.6    -      -       -      +
    191B  ARG*     1.3    77.1    -      -       -      +
    193B  ALA*     1.3    61.2    +      -       -      +
    194B  PHE      3.4     0.3    +      -       -      -
    195B  HIS*     3.5     5.9    +      -       +      +
    196B  SER*     3.8     1.2    +      -       -      -
    236B  LEU*     4.9     0.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 193 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    112B  PHE*     3.5    18.6    -      -       +      -
    189B  PHE      2.9    18.5    +      -       -      +
    190B  GLN      2.9     7.9    +      -       -      +
    192B  LEU*     1.3    77.5    -      -       -      +
    194B  PHE*     1.3    55.1    +      -       -      +
    196B  SER*     2.7    20.8    +      -       -      -
    198B  ASN      3.5     4.5    -      -       -      +
    201B  TYR*     3.4    37.1    -      -       +      +
    202B  GLY*     3.6     3.7    +      -       -      +
    205B  PHE*     3.8    11.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 194 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75A  MET*     3.1    32.8    -      -       +      -
     76A  GLU*     4.2     8.3    -      -       -      -
    190B  GLN*     3.0    34.3    +      -       -      -
    191B  ARG*     3.3     8.7    +      -       -      +
    192B  LEU      3.2     0.4    -      -       -      -
    193B  ALA*     1.3    77.1    -      -       -      +
    195B  HIS*     1.3    62.8    +      -       +      +
    196B  SER*     3.0    10.3    +      -       -      -
    197B  GLY*     3.6     9.7    +      -       -      -
    198B  ASN      4.7     3.8    +      -       -      +
    199B  GLN*     3.7    34.1    -      -       +      -
    202B  GLY*     3.5    17.0    -      -       -      -
    203B  LEU*     3.9     9.4    -      -       +      -
    206B  ASN*     3.1    27.4    -      -       -      -
----------------------------------------------------------
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Residues in contact with HIS 195 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    115B  TYR      4.6     0.2    -      -       -      +
    116B  ALA*     3.2    23.4    -      -       +      -
    119B  LEU*     4.6     0.7    -      -       -      +
    120B  ASN*     3.5    38.3    +      -       +      +
    123B  SER*     3.4    35.6    +      -       -      -
    124B  ALA*     5.3     2.7    -      -       +      +
    127B  ILE*     4.2    22.6    -      -       +      +
    191B  ARG*     2.8    31.7    +      -       +      +
    192B  LEU*     3.5     6.6    +      -       -      +
    194B  PHE*     1.3    80.6    -      -       +      +
    196B  SER*     1.3    59.0    +      -       -      +
    197B  GLY      3.4     1.3    -      -       -      -
----------------------------------------------------------
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A short description of the analytical approach
The contact analysis used in this page is based upon the approach developed in: Sobolev V., Wade R.C., Vriend G. and Edelman M. PROTEINS (1996) 25, 120-129. Contact legitimacy depends on the hydrophobic-hydrophilic properties of the contacting atoms. In order to define it, for each inter-atomic contact, eight atom classes have been introduced:


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

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

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