Contacts of the helix formed by residues 325 - 346 (chain O) in PDB entry 2I2X


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 THR 325 (chain O).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    315O  VAL*     3.3    30.0    -      -       +      +
    316O  GLU      2.7    29.0    +      -       -      +
    317O  TYR*     3.6    14.8    -      -       +      -
    318O  HIS*     2.8    23.1    +      -       -      -
    320O  GLU*     3.7    24.2    +      -       -      +
    323O  GLY      3.6     0.8    +      -       -      -
    324O  THR*     1.3    73.1    -      -       -      +
    326O  VAL*     1.3    69.6    +      -       +      +
    328O  CYS*     3.5     1.5    +      -       -      +
    329O  TRP*     3.1    35.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 326 (chain O). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     43O  ILE*     3.6    11.0    -      -       +      +
     44O  ASN      4.3     4.9    -      -       -      +
     45O  TYR*     3.6    37.5    -      -       +      -
     65O  ILE*     3.9    16.2    -      -       +      +
     68O  ASP*     4.1     4.9    -      -       +      -
     69O  VAL*     3.5    25.6    -      -       +      +
    315O  VAL*     4.4     2.2    -      -       +      -
    317O  TYR*     4.2     9.4    -      -       +      -
    324O  THR*     3.3    19.1    -      -       +      -
    325O  THR*     1.3    91.1    -      -       +      +
    327O  GLN*     1.3    53.1    +      -       -      +
    330O  SER*     2.8    36.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLN 327 (chain O). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     68O  ASP*     3.2    42.6    +      -       +      +
     69O  VAL*     5.4     0.2    -      -       -      +
     71O  GLU*     4.9     6.7    -      -       -      +
     72O  ARG*     3.5    51.0    +      -       +      +
    323O  GLY*     3.6     3.6    -      -       -      -
    324O  THR*     2.7    46.2    +      -       +      +
    326O  VAL*     1.3    77.0    -      -       -      +
    328O  CYS*     1.3    68.1    +      -       -      +
    330O  SER*     3.3     6.2    +      -       -      -
    331O  GLU*     3.2    18.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with CYS 328 (chain O). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    292M  THR*     3.0    56.3    +      -       -      +
    293M  CYS*     4.1     3.6    -      -       -      +
    329M  TRP*     4.6     4.9    -      -       +      -
     72O  ARG*     4.4     2.7    -      -       -      +
    320O  GLU*     4.0    19.7    -      -       +      -
    322O  GLY      4.1     5.2    -      -       -      -
    323O  GLY      3.7    17.3    -      -       -      -
    324O  THR      3.0    21.0    +      -       -      -
    325O  THR      3.8     5.2    -      -       -      +
    327O  GLN*     1.3    78.2    -      -       -      +
    329O  TRP*     1.3    69.0    +      -       +      +
    331O  GLU      3.3     6.8    +      -       -      -
    332O  THR*     3.3     5.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with TRP 329 (chain O). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    320M  GLU*     5.4     4.2    +      -       +      -
    328M  CYS*     4.7     4.9    -      -       +      -
    329M  TRP*     3.3    54.9    -      +       -      +
    332M  THR*     4.3     6.7    -      -       +      -
     43O  ILE*     4.1     7.2    -      -       +      -
    290O  THR*     3.7    40.1    -      -       +      +
    292O  THR*     3.5    26.2    -      -       -      -
    293O  CYS*     3.5    34.0    -      -       +      +
    312O  ASN*     4.1    18.4    -      -       +      +
    315O  VAL*     4.1    19.0    -      -       +      +
    320O  GLU*     5.7     3.6    +      -       -      +
    325O  THR*     3.1    31.3    +      -       -      +
    328O  CYS*     1.3    80.1    -      -       +      +
    330O  SER*     1.3    66.5    +      -       -      +
    332O  THR*     3.3     4.9    +      -       +      +
    333O  LEU*     3.0    26.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 330 (chain O). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     41O  PRO*     4.7     2.4    -      -       -      +
     43O  ILE*     3.8    24.7    -      -       -      +
     69O  VAL*     4.5     7.7    -      -       -      +
     72O  ARG*     4.4     7.3    -      -       -      +
     73O  MET*     4.3    20.6    -      -       -      +
     81O  ILE*     5.2     2.5    -      -       -      -
    326O  VAL      2.8    26.0    +      -       -      -
    327O  GLN*     3.3    10.9    +      -       -      -
    328O  CYS      3.4     0.2    -      -       -      -
    329O  TRP*     1.3    77.1    -      -       -      +
    331O  GLU*     1.3    57.1    +      -       -      +
    333O  LEU*     3.8     6.4    -      -       -      +
    334O  ALA*     2.8    32.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 331 (chain O). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    288M  GLY      5.5     0.7    -      -       -      +
    289M  LYS*     5.5     0.3    -      -       -      -
    292M  THR*     3.5    23.7    -      -       +      +
    296M  SER*     2.6    23.0    +      -       -      -
    297M  ASP*     3.1    34.5    +      -       -      +
     72O  ARG*     3.1    17.9    +      -       +      +
     73O  MET*     5.5     0.2    -      -       -      -
     76O  VAL*     3.5     8.5    -      -       -      +
     78O  PHE*     4.1    14.4    -      -       +      -
    327O  GLN      3.2    12.3    +      -       -      +
    328O  CYS      3.6     9.4    -      -       -      +
    329O  TRP      3.2     0.2    -      -       -      -
    330O  SER*     1.3    77.2    +      -       -      +
    332O  THR*     1.3    56.1    +      -       -      +
    334O  ALA*     3.3     1.6    +      -       -      +
    335O  TYR*     2.9    53.9    +      -       +      -
----------------------------------------------------------
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Residues in contact with THR 332 (chain O). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    289M  LYS*     2.6    36.3    +      -       +      +
    290M  THR*     4.3    12.3    -      -       +      +
    292M  THR*     2.8    19.9    +      -       -      -
    329M  TRP*     4.4     5.1    -      -       +      -
    332M  THR*     4.9     6.1    -      -       +      -
    290O  THR*     3.4    28.7    -      -       +      +
    328O  CYS      3.3     2.3    +      -       -      -
    329O  TRP*     3.3    10.2    +      -       +      -
    330O  SER      3.3     0.6    -      -       -      -
    331O  GLU*     1.3    74.3    -      -       -      +
    333O  LEU*     1.3    66.3    +      -       -      +
    335O  TYR*     3.3     4.5    +      -       -      +
    336O  ASP*     3.0    30.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 333 (chain O). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     41O  PRO*     3.8    14.1    -      -       +      -
     42O  GLU      3.8    19.1    -      -       -      +
     43O  ILE*     4.2     6.3    -      -       +      +
    290O  THR*     3.7    18.6    -      -       +      +
    310O  TRP*     3.5    36.5    -      -       +      +
    311O  SER      3.5    19.3    -      -       -      +
    312O  ASN*     3.7    29.8    -      -       +      +
    329O  TRP      3.0    22.8    +      -       -      +
    330O  SER*     3.8     4.9    -      -       -      +
    332O  THR*     1.3    74.6    -      -       -      +
    334O  ALA*     1.3    58.6    +      -       -      +
    336O  ASP*     3.1     5.7    +      -       -      +
    337O  CYS*     3.0    31.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 334 (chain O). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     41O  PRO*     3.8    13.0    -      -       +      +
     73O  MET*     3.6    13.5    -      -       +      -
     78O  PHE*     3.5    43.7    -      -       +      -
    330O  SER      2.8    23.0    +      -       -      +
    331O  GLU      3.7     0.2    -      -       -      +
    333O  LEU*     1.3    72.5    -      -       -      +
    335O  TYR*     1.3    57.7    +      -       -      +
    337O  CYS*     3.4     4.9    +      -       -      +
    338O  ALA*     3.0    24.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 335 (chain O). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    289M  LYS*     3.7    28.5    -      -       +      -
    297M  ASP      3.0    20.0    +      -       -      -
    298M  VAL*     3.3    12.5    -      -       -      -
    300M  GLY*     3.2    26.4    +      -       -      -
    301M  ASN*     2.9    38.4    -      -       -      +
    359M  SER*     4.6     0.2    -      -       -      -
    360M  ASP*     3.3    23.3    -      -       -      -
    363M  ARG*     3.6    11.7    -      -       -      -
     76O  VAL*     3.4    10.5    -      -       +      +
     78O  PHE*     3.7    10.1    -      +       -      -
    331O  GLU*     2.9    53.1    +      -       +      +
    332O  THR      3.7     4.0    -      -       -      +
    333O  LEU      3.2     0.2    -      -       -      -
    334O  ALA*     1.3    73.8    -      -       -      +
    336O  ASP*     1.3    66.0    +      -       -      +
    337O  CYS      3.0     1.3    -      -       -      -
    338O  ALA*     2.8    12.9    +      -       +      +
    339O  LEU      2.9     3.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with ASP 336 (chain O). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    289M  LYS*     2.8    36.4    +      -       -      +
    289O  LYS*     3.9    12.9    +      -       -      -
    290O  THR*     2.7    29.2    +      -       -      +
    304O  MET*     4.7     5.9    -      -       -      +
    310O  TRP*     2.8    25.2    +      -       +      +
    332O  THR*     3.0    18.7    +      -       -      +
    333O  LEU      3.4     7.6    -      -       -      +
    335O  TYR*     1.3    75.6    -      -       -      +
    337O  CYS*     1.3    62.3    +      -       -      +
    339O  LEU*     3.3     7.2    +      -       -      +
    340O  MET*     3.2    28.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with CYS 337 (chain O). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39O  THR*     3.1    32.4    +      -       -      +
     40O  ILE      3.6     7.2    -      -       -      -
     41O  PRO*     3.6    30.5    -      -       +      -
    310O  TRP*     3.8    21.8    -      -       -      -
    333O  LEU      3.0    16.7    +      -       -      -
    334O  ALA      3.6     8.5    -      -       -      +
    335O  TYR      3.0     0.2    -      -       -      -
    336O  ASP*     1.3    76.3    -      -       -      +
    338O  ALA*     1.3    64.6    +      -       -      +
    340O  MET*     3.3     3.5    +      -       -      -
    341O  ASN*     2.9    32.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 338 (chain O). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    301M  ASN*     4.1     1.1    -      -       -      +
    359M  SER*     3.6    17.5    -      -       -      +
    363M  ARG*     3.8    20.9    -      -       -      +
     12N  VAL*     4.6    12.1    -      -       +      +
     78O  PHE*     5.0     1.8    -      -       +      -
    334O  ALA      3.0    13.4    +      -       -      +
    335O  TYR*     2.8    12.6    +      -       +      +
    337O  CYS*     1.3    76.3    -      -       -      +
    339O  LEU*     1.3    63.3    +      -       -      +
    341O  ASN*     3.9     6.7    -      -       -      +
    342O  THR*     2.8    30.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 339 (chain O). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    289M  LYS*     4.5    14.4    -      -       -      +
    301M  ASN*     3.8    13.1    +      -       +      +
    304M  MET*     5.2     2.9    -      -       +      -
    339M  LEU*     4.4    22.2    -      -       +      -
    352M  LEU*     4.5     9.4    -      -       +      -
    355M  LEU*     3.9    13.3    -      -       +      +
    356M  MET*     3.8    43.1    -      -       +      +
    359M  SER*     4.6     2.0    -      -       -      -
    289O  LYS*     6.1     0.4    -      -       -      +
    304O  MET*     6.5     0.7    -      -       +      -
    335O  TYR      2.9     9.9    +      -       -      +
    336O  ASP*     3.5    10.8    -      -       -      +
    338O  ALA*     1.3    78.5    -      -       -      +
    340O  MET*     1.3    64.1    +      -       +      +
    342O  THR*     3.3     6.5    +      -       -      -
    343O  ALA*     3.1    20.3    +      -       -      +
    352O  LEU*     4.4    14.8    -      -       +      -
    356O  MET*     6.5     0.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with MET 340 (chain O). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19O  PHE*     3.4    41.9    -      -       +      -
     39O  THR*     3.8    19.1    -      -       +      +
    304O  MET*     4.1    26.2    -      -       -      +
    307O  CYS*     3.7    32.5    -      -       -      -
    310O  TRP*     4.6     5.2    -      -       +      -
    336O  ASP      3.2    22.3    +      -       -      +
    337O  CYS*     3.3    22.4    +      -       -      +
    339O  LEU*     1.3    81.2    -      -       +      +
    341O  ASN*     1.3    57.0    +      -       -      +
    343O  ALA*     3.0     6.6    +      -       -      +
    344O  LEU*     2.9    24.4    +      -       -      +
    352O  LEU*     4.1    10.8    -      -       +      -
    356O  MET*     4.6     4.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with ASN 341 (chain O). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     11N  LYS      5.7     1.4    +      -       -      -
     12N  VAL*     4.2    21.2    +      -       +      +
     37O  GLY      5.5     0.7    -      -       -      +
     38O  TYR*     3.6    17.7    -      -       +      +
     39O  THR*     2.8    51.4    +      -       -      +
     79O  PRO*     5.7     5.9    -      -       -      +
    337O  CYS*     2.9    24.1    +      -       -      +
    338O  ALA*     3.9     6.0    -      -       -      +
    339O  LEU      3.2     0.2    -      -       -      -
    340O  MET*     1.3    73.4    -      -       -      +
    342O  THR*     1.3    60.6    +      -       -      +
    344O  LEU*     3.4     8.7    +      -       +      +
    345O  GLU*     2.9    38.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with THR 342 (chain O). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    355M  LEU*     3.5    32.3    -      -       +      +
    358M  LEU*     3.8    26.0    -      -       +      -
    359M  SER*     3.4    17.2    -      -       -      -
      4N  PHE*     3.6    23.6    -      -       +      -
     12N  VAL*     4.1     3.7    -      -       -      +
    338O  ALA      2.8    21.1    +      -       -      -
    339O  LEU      3.5     5.8    -      -       -      -
    340O  MET      3.3     0.2    -      -       -      -
    341O  ASN*     1.3    76.7    -      -       -      +
    343O  ALA*     1.3    54.9    +      -       -      +
    345O  GLU*     3.3     0.7    +      -       -      -
    346O  THR*     2.8    35.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 343 (chain O). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    355M  LEU*     4.0    13.2    -      -       +      +
     19O  PHE*     4.2     0.7    -      -       +      -
    339O  LEU      3.1    10.9    +      -       -      +
    340O  MET      3.0    10.6    +      -       -      +
    342O  THR*     1.3    78.4    -      -       -      +
    344O  LEU*     1.3    61.2    -      -       -      +
    346O  THR*     3.4     4.4    +      -       -      -
    347O  LYS      3.1     4.3    +      -       -      -
    348O  ASN      2.7    47.0    +      -       -      +
    349O  ASP*     3.8     7.4    -      -       -      -
    352O  LEU*     3.8    20.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 344 (chain O). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19O  PHE*     3.4    34.3    -      -       +      +
     20O  GLY*     4.1     4.0    -      -       -      -
     21O  VAL*     3.8    17.5    -      -       +      -
     37O  GLY*     3.5    33.7    -      -       -      +
     38O  TYR*     4.0     2.2    -      -       -      -
    340O  MET      2.9    12.5    +      -       -      +
    341O  ASN*     3.6    25.6    -      -       -      +
    343O  ALA*     1.3    75.9    -      -       -      +
    345O  GLU*     1.3    64.9    +      -       -      +
    347O  LYS*     3.5    17.2    +      -       -      +
    349O  ASP*     3.6    29.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 345 (chain O). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12C  ALA*     5.8     3.3    -      -       -      +
      4N  PHE*     4.0     8.5    -      -       +      -
      7N  ALA      5.2     0.2    -      -       -      -
      8N  SER*     2.6    45.9    +      -       -      +
     11N  LYS*     3.2    40.7    +      -       -      +
     12N  VAL*     3.8    20.1    -      -       +      +
     37O  GLY      4.1     7.8    -      -       -      +
     38O  TYR*     5.8     0.2    -      -       -      +
    341O  ASN*     2.9    25.9    +      -       +      +
    342O  THR      3.9     3.6    -      -       -      +
    343O  ALA      3.2     0.6    -      -       -      -
    344O  LEU*     1.3    79.2    -      -       -      +
    346O  THR*     1.3    58.9    +      -       -      +
    347O  LYS*     3.3    16.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 346 (chain O). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    355M  LEU*     3.5     9.7    -      -       -      +
    358M  LEU*     3.6    29.6    -      -       +      -
      2N  LEU*     4.4    13.7    -      -       +      +
      3N  ASP      3.8    14.4    -      -       -      +
      4N  PHE*     4.3     8.1    -      -       +      -
    342O  THR*     2.8    21.6    +      -       +      +
    343O  ALA      3.5     2.8    +      -       -      -
    345O  GLU*     1.3    77.6    -      -       -      +
    347O  LYS*     1.3    66.0    +      -       -      +
    348O  ASN*     3.0    25.8    +      -       -      +
----------------------------------------------------------
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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