Contacts of the helix formed by residues 220 - 246 (chain C) in PDB entry 1L0N


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 PHE 220 (chain C).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     17C  ALA      5.2     2.2    -      -       -      -
     18C  PHE*     3.0    50.3    -      +       +      +
     19C  ILE      3.5     3.5    +      -       -      +
     21C  LEU*     2.8    39.8    +      -       +      +
     23C  ALA*     4.6     5.6    -      -       +      -
     27C  ILE*     6.0     2.5    -      -       +      -
    218C  ILE      4.4     0.9    -      -       -      -
    219C  PRO*     1.3    72.4    -      -       -      +
    221C  HIS*     1.3    66.7    +      -       -      +
    224C  TYR*     3.2    45.8    +      +       +      -
    225C  THR*     3.4    20.9    +      -       +      -
    228C  ASP*     3.4    24.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with HIS 221 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    436A  ARG*     3.8    21.1    -      -       +      +
     18C  PHE      4.0     7.9    -      -       -      +
     19C  ILE*     3.1    30.8    +      -       +      +
    219C  PRO*     2.9     7.5    -      -       -      +
    220C  PHE*     1.3    87.4    -      -       -      +
    222C  PRO*     1.3    95.0    -      -       +      +
    223C  TYR*     2.1     6.9    +      -       -      +
    225C  THR*     3.0    32.7    +      -       +      +
    226D  LYS*     6.3     0.4    -      -       -      -
----------------------------------------------------------
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Residues in contact with PRO 222 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    433A  ASP*     4.8     3.4    -      -       -      +
    435A  ASN*     3.7    29.4    -      -       +      +
    436A  ARG*     3.5    23.8    -      -       +      -
    439A  SER*     6.5     0.2    -      -       -      -
    219C  PRO*     5.0     4.9    -      -       +      -
    221C  HIS*     1.3   107.4    -      -       +      +
    223C  TYR*     1.3    66.2    +      -       +      +
    225C  THR*     3.1    14.7    +      -       -      +
    226C  ILE*     3.1    18.9    +      -       +      +
    226D  LYS*     3.6    34.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 223 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    433A  ASP*     2.8    47.2    +      -       +      -
    435A  ASN*     2.9    13.9    +      -       -      -
    218C  ILE*     3.6    30.7    -      -       +      -
    219C  PRO*     3.8    18.2    -      -       +      +
    221C  HIS      2.1     9.1    +      -       -      +
    222C  PRO*     1.3    73.2    -      -       +      +
    224C  TYR*     1.3    61.7    +      -       +      +
    227C  LYS*     3.3    12.6    +      -       -      +
    226D  LYS      3.1    25.8    -      -       -      -
    227D  TRP*     2.8    52.3    +      +       +      +
    229D  VAL*     3.7     7.8    -      -       -      +
    230D  LEU*     3.5    31.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 224 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     23C  ALA*     3.9    21.3    -      -       +      -
     24C  PRO      2.7    28.6    +      -       -      -
     25C  SER      3.6     3.6    -      -       -      -
     27C  ILE*     3.0    41.5    +      -       +      +
     32C  ASN*     5.8     1.3    -      -       -      -
    218C  ILE*     3.8    14.6    -      -       +      -
    220C  PHE*     3.2    35.2    +      +       +      -
    221C  HIS      3.2     3.6    +      -       -      -
    223C  TYR*     1.3    81.5    -      -       +      +
    225C  THR*     1.3    62.7    +      -       -      +
    226C  ILE      3.4     0.4    -      -       -      -
    227C  LYS*     3.8    24.9    -      -       +      +
    228C  ASP*     2.9    33.1    +      -       -      +
    227D  TRP*     3.5    30.3    -      +       -      -
----------------------------------------------------------
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Residues in contact with THR 225 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     18C  PHE*     3.9    10.1    -      -       +      +
     19C  ILE*     5.8     1.6    -      -       +      -
    220C  PHE*     3.4    29.2    +      -       +      +
    221C  HIS*     3.0    35.6    +      -       +      +
    222C  PRO*     3.1     7.8    +      -       -      +
    224C  TYR*     1.3    74.8    -      -       -      +
    226C  ILE*     1.3    65.0    +      -       -      +
    228C  ASP*     2.9    21.9    +      -       -      +
    229C  ILE*     2.9    22.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 226 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    222C  PRO*     3.1    17.3    +      -       +      +
    223C  TYR      4.1     3.8    -      -       -      +
    225C  THR*     1.3    84.4    +      -       -      +
    227C  LYS*     1.3    62.6    +      -       -      +
    229C  ILE*     3.5    14.6    +      -       +      +
    230C  LEU*     3.3    18.7    +      -       -      +
    219D  VAL*     4.1     5.8    -      -       +      +
    222D  MET*     3.8    29.6    -      -       +      +
    223D  LYS*     3.7    47.0    -      -       +      +
    226D  LYS*     4.9    14.8    -      -       +      -
    227D  TRP*     4.4     5.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 227 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27C  ILE*     3.3    26.6    +      -       -      -
     28C  SER*     4.1    12.9    -      -       -      +
     29C  SER*     4.3     5.2    +      -       -      +
     32C  ASN*     3.5    32.8    -      -       -      +
    223C  TYR      3.3    18.3    +      -       -      +
    224C  TYR*     4.0    24.7    -      -       +      -
    225C  THR      3.2     0.8    -      -       -      -
    226C  ILE*     1.3    79.1    -      -       -      +
    228C  ASP*     1.3    61.0    +      -       -      +
    230C  LEU*     3.7     5.5    +      -       +      +
    231C  GLY      3.0    19.2    +      -       -      -
    223D  LYS*     3.9    37.0    -      -       +      +
    227D  TRP*     4.3     7.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASP 228 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31C  TRP      5.4     0.5    -      -       -      +
     32C  ASN*     4.1    18.7    +      -       -      +
     35C  SER*     3.5    35.3    +      -       -      +
     36C  LEU*     5.1     0.2    -      -       -      +
    220C  PHE*     3.4    19.5    -      -       -      -
    224C  TYR*     2.9    24.6    +      -       -      +
    225C  THR*     2.9     6.5    +      -       -      +
    227C  LYS*     1.3    78.6    -      -       -      +
    229C  ILE*     1.3    56.8    +      -       +      +
    231C  GLY*     3.1     1.3    +      -       -      +
    232C  ALA*     2.6    36.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 229 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    225C  THR*     2.9    20.7    +      -       -      +
    226C  ILE*     3.6    20.6    -      -       +      +
    227C  LYS      3.3     0.2    -      -       -      -
    228C  ASP*     1.3    75.0    -      -       +      +
    230C  LEU*     1.3    56.5    +      -       -      +
    232C  ALA*     2.7    30.2    +      -       -      +
    233C  LEU*     2.9    13.2    +      -       +      +
    219D  VAL*     4.2    18.2    -      -       +      -
    222D  MET*     5.4     5.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 230 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    226C  ILE      3.3    12.2    +      -       -      +
    227C  LYS*     3.9     6.3    -      -       +      +
    229C  ILE*     1.3    78.3    -      -       -      +
    231C  GLY*     1.3    62.2    +      -       -      +
    233C  LEU*     3.3    18.0    -      -       +      +
    234C  LEU*     3.3    18.5    +      -       +      +
    216D  LEU*     4.0    24.7    -      -       +      +
    219D  VAL*     3.7    29.8    -      -       +      +
    220D  TYR*     4.0    35.4    -      -       +      +
    223D  LYS*     4.2    30.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 231 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     32C  ASN*     4.1    13.5    -      -       -      -
     36C  LEU*     3.5    19.8    -      -       -      +
    227C  LYS      3.0    15.3    +      -       -      -
    228C  ASP      3.1     5.6    +      -       -      -
    229C  ILE      2.8     2.6    +      -       -      -
    230C  LEU*     1.3    74.5    -      -       -      +
    232C  ALA*     1.3    61.9    +      -       -      -
    234C  LEU*     3.3    18.3    +      -       -      +
    235C  LEU      3.3     8.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 232 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     36C  LEU*     3.6    11.6    -      -       +      +
     39C  ILE*     3.9    32.7    -      -       +      +
    228C  ASP      2.6    16.1    +      -       -      +
    229C  ILE*     2.7    11.5    +      -       -      +
    231C  GLY*     1.3    72.3    -      -       -      -
    233C  LEU*     1.3    55.8    +      -       -      +
    235C  LEU*     3.0     5.1    +      -       -      +
    236C  ILE*     2.9    33.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 233 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    229C  ILE*     2.9    11.6    +      -       +      +
    230C  LEU*     3.3    11.7    -      -       -      +
    232C  ALA*     1.3    78.6    -      -       -      +
    234C  LEU*     1.3    56.9    +      -       -      +
    236C  ILE*     3.2    11.7    +      -       +      +
    237C  LEU*     3.0    26.0    +      -       -      +
    212D  MET*     4.1    20.1    -      -       +      +
    215D  LEU*     4.2    16.2    -      -       +      -
    216D  LEU*     3.9    37.0    -      -       +      +
    219D  VAL*     3.8    33.0    -      -       +      -
     47E  VAL*     6.1     3.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 234 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    230C  LEU*     3.3    23.3    +      -       +      +
    231C  GLY*     3.3    11.5    +      -       -      +
    232C  ALA      3.2     0.6    -      -       -      -
    233C  LEU*     1.3    74.2    -      -       -      +
    235C  LEU*     1.4    64.9    +      -       -      +
    237C  LEU*     3.4    11.1    +      -       +      +
    238C  ALA*     3.0    23.4    +      -       -      +
    216D  LEU*     3.8    34.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 235 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     36C  LEU*     3.8    27.6    -      -       +      +
     39C  ILE*     3.8    26.2    -      -       +      -
     40C  CYS*     3.6    25.4    -      -       -      -
     43C  LEU*     5.8     4.5    -      -       +      -
     89C  MET*     3.7    19.7    -      -       +      -
     93C  CYS*     3.6    30.7    -      -       -      -
    231C  GLY      3.3     4.4    +      -       -      -
    232C  ALA      3.0    10.6    +      -       -      +
    234C  LEU*     1.4    75.0    -      -       -      +
    236C  ILE*     1.3    59.2    +      -       +      +
    238C  ALA*     3.3     5.9    +      -       -      +
    239C  LEU*     2.8    36.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 236 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39C  ILE*     5.5     5.6    -      -       +      -
     43C  LEU*     4.4    23.1    -      -       +      -
    232C  ALA*     2.9    19.9    +      -       +      +
    233C  LEU*     3.5    13.9    -      -       +      +
    235C  LEU*     1.3    81.9    -      -       +      +
    237C  LEU*     1.3    54.0    +      -       -      +
    239C  LEU*     3.1    10.4    +      -       +      -
    240C  MET*     2.6    52.9    +      -       +      +
    212D  MET*     3.8    16.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 237 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    233C  LEU      3.0    13.4    +      -       -      +
    234C  LEU*     3.6    17.3    -      -       +      +
    236C  ILE*     1.3    75.2    -      -       -      +
    238C  ALA*     1.3    56.0    +      -       -      +
    241C  LEU*     2.7    61.4    +      -       +      +
    208D  MET*     3.7    22.9    -      -       -      -
    209D  LEU*     4.9     6.1    -      -       +      -
    212D  MET*     3.8    23.1    -      -       +      +
    216D  LEU*     3.8    25.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 238 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     89C  MET*     3.7    23.3    -      -       +      -
    234C  LEU      3.0    14.3    +      -       -      +
    235C  LEU*     3.7     7.9    -      -       -      +
    237C  LEU*     1.3    75.8    -      -       -      +
    239C  LEU*     1.3    64.2    +      -       -      +
    241C  LEU*     3.6     8.1    -      -       -      +
    242C  LEU*     2.9    27.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 239 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     43C  LEU*     3.6    36.6    -      -       +      -
     82C  MET*     4.0     8.1    -      -       +      +
     85C  ASN*     3.7    15.0    -      -       +      -
     86C  GLY*     3.6    29.8    -      -       -      +
     89C  MET*     3.7    20.1    -      -       +      -
    235C  LEU*     2.8    25.7    +      -       +      +
    236C  ILE*     3.5    11.0    -      -       +      +
    238C  ALA*     1.3    72.4    -      -       -      +
    240C  MET*     1.3    77.9    +      -       +      +
    242C  LEU*     3.0     7.8    +      -       -      +
    243C  VAL*     2.8    33.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with MET 240 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     82C  MET*     3.6    45.5    -      -       +      -
    236C  ILE*     2.6    42.3    +      -       +      +
    239C  LEU*     1.3    85.0    -      -       +      +
    241C  LEU*     1.3    60.2    +      -       -      +
    243C  VAL*     3.8    12.3    -      -       +      +
    244C  LEU*     2.8    48.0    +      -       +      +
    208D  MET*     3.7    29.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 241 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    237C  LEU*     2.7    38.8    +      -       +      +
    238C  ALA*     3.6     7.0    -      -       -      +
    240C  MET*     1.3    70.5    -      -       -      +
    242C  LEU*     1.3    66.4    +      -       +      +
    245C  PHE*     3.3    50.0    +      -       +      +
    246C  ALA*     3.7     1.9    +      -       -      +
    208D  MET*     3.6    15.1    -      -       +      +
    209D  LEU*     3.9    15.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 242 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     85C  ASN*     3.3    37.0    -      -       +      +
     88C  SER*     5.1     0.2    -      -       -      -
     89C  MET*     5.0    11.7    -      -       -      -
    238C  ALA*     2.9    15.2    +      -       +      +
    239C  LEU*     3.0    10.2    +      -       -      +
    241C  LEU*     1.3    75.8    -      -       +      +
    243C  VAL*     1.3    58.0    +      -       -      +
    246C  ALA*     2.9    46.4    +      -       +      +
    249C  LEU*     4.9    17.3    -      -       +      -
    250C  LEU*     3.8    29.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 243 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     77C  TRP*     5.4     0.6    -      -       +      -
     78C  ILE*     4.3     8.5    -      -       +      -
     81C  TYR*     3.8    26.6    -      -       +      +
     82C  MET*     4.0    12.1    -      -       +      -
     85C  ASN*     3.5    33.4    -      -       +      +
    239C  LEU*     2.8    24.2    +      -       +      +
    240C  MET*     3.8    27.1    -      -       +      -
    242C  LEU*     1.3    71.8    -      -       -      +
    244C  LEU*     1.3    73.6    +      -       +      +
    247C  PRO*     3.2    20.3    -      -       -      +
    201D  ARG*     4.6     2.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 244 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     77C  TRP*     4.2    11.9    -      -       +      -
     78C  ILE*     4.1    25.4    -      -       +      -
    240C  MET*     2.8    33.9    +      -       +      +
    243C  VAL*     1.3    79.1    -      -       +      +
    245C  PHE*     1.3    60.5    +      -       +      +
    247C  PRO*     3.9     0.3    -      -       -      +
    201D  ARG*     2.4    57.6    +      -       -      +
    204D  MET*     4.1    13.2    -      -       +      -
    205D  GLY*     3.7    31.0    -      -       -      +
    208D  MET*     3.9    23.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 245 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    241C  LEU*     3.3    44.6    +      -       +      +
    244C  LEU*     1.3    79.4    -      -       +      +
    246C  ALA*     1.3    59.8    +      -       +      +
    247C  PRO*     3.5     3.1    -      -       -      +
     17D  LEU*     3.7    42.4    -      -       +      -
     18D  LEU*     3.8    21.8    -      -       +      -
    201D  ARG*     3.0    20.4    +      -       -      +
    202D  LYS*     4.8    11.4    -      -       +      -
    205D  GLY*     3.6    41.1    -      -       -      -
    208D  MET*     4.1     4.5    -      -       +      -
    209D  LEU*     3.7    20.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 246 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     85C  ASN*     4.7     1.0    +      -       -      +
    241C  LEU      3.7     1.7    +      -       -      +
    242C  LEU*     2.9    29.1    +      -       +      +
    245C  PHE*     1.3    77.4    -      -       +      +
    247C  PRO*     1.3    64.6    -      -       -      +
    248C  ASP      3.3     2.5    -      -       -      -
    249C  LEU*     3.2    44.3    +      -       +      +
----------------------------------------------------------
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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