Contacts of the helix formed by residues 180 - 206 (chain E) in PDB entry 4PHZ


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 GLY 180 (chain E).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    178E  HIS      3.2     1.6    +      -       -      -
    179E  TYR*     1.3    83.2    -      -       -      +
    181E  ILE*     1.3    62.2    +      -       -      +
    182E  SER*     3.2     3.7    -      -       -      +
    183E  ARG*     3.2    21.3    +      -       -      +
    184E  VAL*     3.3    14.0    +      -       -      +
    171F  ALA*     4.7    10.5    -      -       -      +
    172F  PHE*     3.8    19.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 181 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    177E  GLU      3.8    22.7    -      -       -      +
    178E  HIS*     3.4    17.2    +      -       -      +
    179E  TYR      3.3     0.4    -      -       -      -
    180E  GLY*     1.3    76.2    -      -       -      +
    182E  SER*     1.3    61.6    +      -       -      +
    184E  VAL*     3.4    10.6    +      -       -      +
    185E  TYR*     3.3    48.6    +      -       +      +
    120F  PRO*     4.4     2.5    -      -       +      -
    121F  ILE*     4.0    20.6    -      -       +      +
    122F  SER*     3.6    42.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with SER 182 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    178E  HIS      4.6     2.4    +      -       -      -
    180E  GLY      3.2     2.0    -      -       -      +
    181E  ILE*     1.3    74.3    -      -       -      +
    183E  ARG*     1.3    55.3    +      -       -      +
    184E  VAL      3.2     0.2    +      -       -      -
    185E  TYR*     3.3    11.1    +      -       -      +
    186E  ALA*     2.8    34.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 183 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    180E  GLY*     3.5    12.3    -      -       -      +
    182E  SER*     1.3    79.2    -      -       -      +
    184E  VAL*     1.3    62.6    +      -       +      +
    186E  ALA*     3.2    10.3    +      -       +      +
    187E  TRP*     3.0    24.5    +      -       +      +
    249E  VAL*     5.2     4.4    -      -       -      +
    250E  THR*     3.5    25.4    -      -       +      +
    253E  THR*     3.5    28.5    +      -       -      +
    254E  PHE*     3.4    33.0    -      -       -      -
    167F  PRO      3.9    21.0    -      -       -      +
    168F  ALA*     5.4     2.2    -      -       -      +
    171F  ALA*     4.2    11.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 184 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    180E  GLY      3.3    13.8    +      -       -      +
    181E  ILE*     3.5    11.0    -      -       -      +
    182E  SER      3.1     0.6    -      -       -      -
    183E  ARG*     1.3    75.5    -      -       +      +
    185E  TYR*     1.3    59.8    +      -       -      +
    187E  TRP*     3.1     5.5    +      -       -      +
    188E  HIS*     2.8    32.3    +      -       +      +
    106F  TRP*     3.6    30.3    -      -       +      -
    121F  ILE*     4.8     4.5    -      -       +      +
    125F  PHE*     3.8    29.2    -      -       +      -
    168F  ALA*     3.8    30.5    -      -       +      +
    172F  PHE*     4.1    13.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 185 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    181E  ILE*     3.3    36.1    +      -       +      +
    182E  SER*     3.6     8.3    -      -       -      +
    184E  VAL*     1.3    77.0    -      -       +      +
    186E  ALA*     1.3    62.8    +      -       -      +
    188E  HIS*     4.4     2.0    -      -       -      +
    189E  LEU*     3.0    52.8    +      -       +      +
    190E  PRO*     3.5     4.3    -      -       -      +
    106F  TRP*     3.7    33.9    -      +       -      -
    110F  TYR*     3.7    23.5    -      +       -      -
    121F  ILE*     3.5    23.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 186 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    182E  SER      2.8    17.7    +      -       -      +
    183E  ARG*     3.2    15.7    +      -       +      +
    185E  TYR*     1.3    73.0    -      -       -      +
    187E  TRP*     1.3    59.7    +      -       -      +
    190E  PRO*     2.9    25.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with TRP 187 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    183E  ARG      3.0    12.0    +      -       -      +
    184E  VAL      3.6     6.1    -      -       -      +
    186E  ALA*     1.3    80.7    -      -       -      +
    188E  HIS*     1.3    79.0    +      +       +      +
    189E  LEU      3.5     0.2    -      -       -      -
    190E  PRO*     3.8     3.1    -      -       +      +
    191E  TRP*     3.2    66.2    +      +       -      -
    242E  ALA*     3.8    22.0    -      -       +      -
    243E  THR*     4.7     7.0    -      -       -      -
    246E  GLY*     4.0    22.2    -      -       -      -
    128F  ALA*     4.8     4.2    -      -       +      +
    163F  PRO      5.2     0.2    -      -       -      -
    164F  ASN*     2.8    34.8    +      -       +      -
    167F  PRO*     3.7    33.7    -      -       +      +
    168F  ALA*     4.3    12.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with HIS 188 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    184E  VAL*     2.8    25.8    +      -       +      +
    185E  TYR*     4.6     0.2    -      -       -      -
    187E  TRP*     1.3    82.3    -      +       -      +
    189E  LEU*     1.3    68.1    +      -       +      +
    191E  TRP*     3.4     6.8    +      -       -      +
    192E  MET*     3.1    25.7    +      -       -      +
    102F  LEU*     4.6     5.3    -      -       +      +
    106F  TRP*     2.9    46.8    +      +       +      +
    125F  PHE*     4.5     2.6    -      +       -      -
    126F  PRO*     3.1    31.3    +      -       +      -
    127F  SER      4.1     4.3    -      -       -      -
    128F  ALA*     3.9    24.4    +      -       +      +
    165F  ASN*     4.9     0.8    +      -       -      -
    168F  ALA*     4.1    24.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 189 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    185E  TYR*     3.0    43.7    +      -       +      +
    188E  HIS*     1.3    84.1    -      -       +      +
    190E  PRO*     1.3    74.0    -      -       +      +
    192E  MET*     3.2    20.0    +      -       +      +
    193E  ALA*     2.8    24.6    +      -       -      +
    106F  TRP*     4.9     9.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with PRO 190 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    185E  TYR      3.5     5.2    -      -       -      +
    186E  ALA*     2.9    29.8    -      -       -      +
    187E  TRP*     3.8     4.7    -      -       +      +
    189E  LEU*     1.3    89.8    -      -       +      +
    191E  TRP*     1.3    54.7    +      -       +      +
    193E  ALA*     3.1     9.8    +      -       +      +
    194E  VAL*     2.7    40.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with TRP 191 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    187E  TRP*     3.2    63.8    +      +       -      +
    188E  HIS*     3.4     9.0    +      -       -      +
    189E  LEU      3.3     0.8    -      -       -      -
    190E  PRO*     1.3    80.8    -      -       +      +
    192E  MET*     1.3    57.9    +      -       -      +
    194E  VAL*     3.2    28.2    +      -       +      +
    195E  GLY      2.8    25.6    +      -       -      -
    239E  THR*     3.6    32.5    -      -       +      -
    242E  ALA*     4.0    21.8    -      -       +      -
    243E  THR*     4.1     7.0    -      -       -      -
    130F  ILE*     3.6    36.9    -      -       +      +
    131F  VAL*     3.5    31.3    -      -       +      +
    134F  ILE*     4.2     3.1    -      -       +      -
    164F  ASN*     5.6     3.1    -      -       -      -
----------------------------------------------------------
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Residues in contact with MET 192 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    188E  HIS*     3.1    19.0    +      -       -      +
    189E  LEU*     3.2    19.7    +      -       +      +
    191E  TRP*     1.3    75.6    -      -       -      +
    193E  ALA*     1.3    58.2    -      -       -      +
    195E  GLY      3.3     0.5    +      -       -      -
    196E  ALA*     2.9    29.6    +      -       -      +
     99F  LEU*     3.7    17.9    -      -       +      +
    102F  LEU*     3.9     9.4    -      -       +      -
    103F  ILE*     3.3    46.2    -      -       +      +
    106F  TRP*     3.6    32.1    -      -       +      -
    130F  ILE*     3.8    16.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 193 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    189E  LEU      2.8    13.8    +      -       -      +
    190E  PRO*     3.2    13.2    -      -       +      +
    192E  MET*     1.3    74.6    -      -       -      +
    194E  VAL*     1.3    57.8    +      -       +      +
    196E  ALA*     3.2     8.0    +      -       -      +
    197E  ALA*     2.8    29.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 194 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    190E  PRO*     2.7    22.1    +      -       +      +
    191E  TRP*     3.5    36.6    -      -       +      +
    193E  ALA*     1.3    70.2    -      -       +      +
    195E  GLY*     1.3    66.3    +      -       -      +
    197E  ALA*     3.1     9.6    +      -       -      +
    198E  TRP*     3.0    25.0    +      -       +      +
    235E  VAL*     5.8     6.3    -      -       +      -
    239E  THR*     5.5     2.2    -      -       -      +
    134F  ILE*     4.4    10.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 195 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    191E  TRP      2.8    17.9    +      -       -      -
    192E  MET      3.7     3.6    -      -       -      -
    194E  VAL*     1.3    76.9    -      -       -      +
    196E  ALA*     1.3    60.7    +      -       -      +
    198E  TRP*     3.2     5.6    +      -       -      +
    199E  ILE*     3.1    23.9    +      -       -      +
     95F  VAL*     3.7    21.2    -      -       -      +
     99F  LEU*     4.3     4.5    -      -       -      -
    130F  ILE*     4.5    12.1    -      -       -      -
    134F  ILE*     5.6     1.6    -      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 196 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    192E  MET      2.9    13.5    +      -       -      +
    193E  ALA*     3.6     8.7    -      -       -      +
    195E  GLY*     1.3    72.2    -      -       -      +
    197E  ALA*     1.3    66.5    +      -       -      +
    198E  TRP      3.2     0.2    +      -       -      -
    199E  ILE*     3.2     4.5    +      -       -      +
    200E  PHE*     2.8    46.2    +      -       +      -
     99F  LEU*     3.8    19.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 197 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    193E  ALA      2.8    16.9    +      -       -      +
    194E  VAL*     3.4    13.2    -      -       -      +
    196E  ALA*     1.3    72.7    -      -       -      +
    198E  TRP*     1.3    51.1    +      -       -      +
    200E  PHE*     3.1     6.8    +      -       -      +
    201E  PHE*     2.7    36.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with TRP 198 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    194E  VAL*     3.0    13.8    +      -       +      +
    195E  GLY*     3.5     9.0    -      -       -      +
    196E  ALA      3.2     0.2    -      -       -      -
    197E  ALA*     1.3    71.9    -      -       -      +
    199E  ILE*     1.3    67.5    +      -       -      +
    201E  PHE*     3.5     7.6    +      +       -      +
    202E  TRP*     2.9    69.2    +      +       -      -
    231E  ILE*     5.1     1.6    -      -       +      -
    232E  GLY*     4.2     9.0    -      -       -      -
    235E  VAL*     3.8    43.3    -      -       +      -
     91F  PRO      3.5    25.6    +      -       -      -
     92F  PHE*     3.6    17.0    -      -       +      +
     95F  VAL*     4.0    26.4    -      -       +      +
    134F  ILE*     5.6     9.0    -      -       +      -
    137F  ASP*     4.4     5.1    +      -       +      -
    138F  VAL*     3.7    28.5    -      -       +      -
    141F  LEU*     4.2     6.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 199 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    195E  GLY      3.1     8.1    +      -       -      +
    196E  ALA*     3.6     6.7    -      -       -      +
    198E  TRP*     1.3    81.0    -      -       -      +
    200E  PHE*     1.3    72.2    +      -       +      +
    202E  TRP      3.3     0.7    +      -       -      -
    203E  PHE*     3.0    19.2    +      -       +      +
     31F  LEU*     4.5    19.7    -      -       +      -
     35F  PHE*     4.9     4.9    -      -       +      -
     92F  PHE*     3.8    38.4    -      -       +      -
     95F  VAL*     4.0    11.9    -      -       +      +
     96F  PHE*     3.7    36.1    -      -       +      +
     99F  LEU*     3.8    28.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 200 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    196E  ALA*     2.8    49.2    +      -       +      -
    197E  ALA*     3.6     7.4    -      -       -      +
    199E  ILE*     1.3    78.2    -      -       +      +
    201E  PHE*     1.3    70.3    +      -       -      +
    203E  PHE*     3.3    11.4    +      +       -      +
    204E  VAL*     3.0    27.8    +      -       +      +
     28F  TRP*     3.6    39.7    -      +       -      -
     31F  LEU*     4.9     8.5    -      -       +      -
     99F  LEU*     6.2     0.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 201 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    197E  ALA      2.7    16.5    +      -       -      +
    198E  TRP*     3.5    14.4    -      +       -      +
    199E  ILE      3.2     0.2    -      -       -      -
    200E  PHE*     1.3    77.0    -      -       -      +
    202E  TRP*     1.3   113.5    +      +       -      +
    204E  VAL*     2.9    16.2    +      -       +      +
    205E  ARG*     3.0    54.6    +      -       +      +
    228E  ASP*     5.9     0.2    -      -       -      -
    231E  ILE*     3.7    33.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with TRP 202 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    198E  TRP*     2.9    74.2    -      +       -      -
    199E  ILE      3.3     1.4    +      -       -      -
    201E  PHE*     1.3   101.8    -      +       -      +
    203E  PHE*     1.3    62.8    +      -       -      +
    204E  VAL      3.1     0.9    +      -       -      -
    205E  ARG*     4.6     1.6    -      -       -      +
    206E  LYS*     3.1    42.8    +      -       +      +
    224E  ILE*     3.8    17.0    -      -       +      -
    228E  ASP*     3.7    45.5    -      -       +      -
    231E  ILE*     4.5     5.6    -      -       +      -
     90F  LEU*     3.8     7.2    -      -       +      +
     91F  PRO*     3.6    28.5    -      -       +      -
     92F  PHE*     3.7    20.4    -      +       +      -
    141F  LEU*     4.1    11.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 203 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    199E  ILE      3.0    17.2    +      -       -      +
    200E  PHE*     3.7    10.3    -      +       -      +
    201E  PHE      3.2     0.4    -      -       -      -
    202E  TRP*     1.3    77.3    -      -       -      +
    204E  VAL*     1.3    68.2    +      -       +      +
    206E  LYS      2.6    17.3    -      -       -      +
    207E  GLY*     4.1     4.4    -      -       -      -
    208E  ILE*     3.5    29.8    -      -       +      -
     24F  GLN*     4.2     8.5    -      -       -      -
     27F  ASP*     3.5    45.7    -      -       +      +
     28F  TRP*     3.8    44.0    -      +       -      -
     31F  LEU*     4.0    23.1    -      -       +      -
     90F  LEU*     5.0     2.5    -      -       -      -
     92F  PHE*     4.1    10.5    -      +       +      -
----------------------------------------------------------
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Residues in contact with VAL 204 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    200E  PHE*     3.0    20.5    +      -       +      +
    201E  PHE*     2.9     5.0    +      -       -      +
    203E  PHE*     1.3    90.9    -      -       +      +
    205E  ARG*     1.3    70.2    +      -       +      +
    206E  LYS      2.8    16.2    +      -       -      +
    207E  GLY*     5.0     0.3    -      -       -      -
     28F  TRP*     5.6     5.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 205 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    201E  PHE*     3.0    59.7    +      -       +      +
    202E  TRP*     4.6     2.0    -      -       +      +
    204E  VAL*     1.3    80.7    -      -       +      +
    206E  LYS*     1.3    83.3    +      -       +      +
    231E  ILE*     4.7     8.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 206 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    202E  TRP*     3.1    31.0    +      -       +      +
    203E  PHE      2.6    23.4    -      -       -      +
    204E  VAL      3.4     4.2    -      -       -      +
    205E  ARG*     1.3   103.7    -      -       +      +
    207E  GLY*     1.3    62.8    +      -       -      +
    210E  THR*     5.7     2.7    -      -       +      -
    211E  SER*     3.3    19.7    -      -       -      +
    214E  ARG*     5.4     7.4    -      -       -      +
    222E  ASP      5.3     1.7    +      -       -      +
    223E  VAL*     2.8    38.3    +      -       +      +
    224E  ILE*     5.4     0.7    -      -       +      -
    228E  ASP*     2.7    34.8    +      -       -      -
     90F  LEU*     4.1    10.8    -      -       +      -
----------------------------------------------------------
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A short description of the analytical approach
The contact analysis used in this page is based upon the approach developed in: Sobolev V., Wade R.C., Vriend G. and Edelman M. PROTEINS (1996) 25, 120-129. Contact legitimacy depends on the hydrophobic-hydrophilic properties of the contacting atoms. In order to define it, for each inter-atomic contact, eight atom classes have been introduced:


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

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