Contacts of the helix formed by residues 343 - 367 (chain A) in PDB entry 3QJQ


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 ASN 343 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    254A  GLN*     4.3    24.7    +      -       -      +
    340A  PRO*     3.1    21.5    +      -       +      +
    341A  TRP      3.2     0.8    -      -       -      -
    342A  ASP*     1.3    79.0    +      -       -      +
    344A  PRO*     1.3    74.6    -      -       -      +
    345A  ALA*     2.8    19.6    +      -       -      +
    346A  PHE*     2.8    24.4    +      -       -      +
    347A  VAL*     3.1    13.4    +      -       -      +
    402A  TYR*     5.4     1.0    -      -       -      +
    418A  ARG*     5.2     2.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with PRO 344 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    342A  ASP      3.5     9.2    -      -       -      +
    343A  ASN*     1.3    89.4    -      -       -      +
    345A  ALA*     1.3    56.8    -      -       -      +
    347A  VAL*     3.8     8.5    -      -       +      -
    348A  ALA*     2.9    35.2    +      -       -      +
    399A  GLY*     4.0     2.5    -      -       -      +
    402A  TYR*     3.8    38.4    -      -       +      -
    418A  ARG*     3.7    26.2    -      -       +      +
    421A  GLY*     4.7     4.0    -      -       -      -
    422A  LEU*     4.4    23.7    -      -       +      +
    425A  VAL*     4.7     7.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 345 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    251A  LEU*     4.2     3.7    -      -       -      +
    254A  GLN*     3.7    14.5    -      -       -      +
    343A  ASN*     2.8    16.4    +      -       -      +
    344A  PRO*     1.3    77.1    -      -       -      +
    346A  PHE*     1.3    62.4    +      -       -      +
    349A  PRO*     3.2    19.2    -      -       -      +
    399A  GLY      3.0    22.0    +      -       -      +
    400A  SER*     5.3     0.5    +      -       -      -
    402A  TYR*     4.6     8.9    -      -       +      +
    403A  TRP*     3.6    25.6    +      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 346 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    251A  LEU*     4.0    13.4    -      -       +      +
    254A  GLN*     4.8     5.6    -      -       +      +
    255A  ALA*     4.2    10.8    -      -       +      -
    320A  LEU*     3.6    25.6    -      -       +      -
    339A  LEU*     3.4    31.0    -      -       +      -
    340A  PRO*     3.6    38.1    -      -       +      +
    341A  TRP*     3.5    42.6    -      +       -      -
    343A  ASN*     2.8    14.2    +      -       -      +
    345A  ALA*     1.3    75.8    -      -       -      +
    347A  VAL*     1.3    85.1    +      -       +      +
    349A  PRO*     3.0    13.2    -      -       -      +
    350A  VAL*     3.1    34.0    -      -       +      +
    801A  HAS      6.1     0.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 347 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    341A  TRP*     3.3    52.5    -      -       +      +
    343A  ASN      3.1    13.2    +      -       -      +
    344A  PRO*     4.0     4.3    -      -       +      +
    346A  PHE*     1.3    82.5    -      -       +      +
    348A  ALA*     1.3    65.8    +      -       -      +
    350A  VAL*     2.8    14.0    +      -       -      -
    351A  LEU*     2.9    39.0    +      -       +      +
    422A  LEU*     4.0    10.3    -      -       +      -
    425A  VAL*     4.2     8.7    -      -       +      -
    426A  TRP*     3.9    13.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 348 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    344A  PRO      2.9    21.0    +      -       -      +
    347A  VAL*     1.3    72.9    -      -       -      +
    349A  PRO*     1.4    64.6    -      -       +      +
    351A  LEU*     4.2     0.4    -      -       -      +
    352A  GLY      3.0    18.7    +      -       -      -
    395A  LEU*     3.2    43.3    -      -       +      +
    399A  GLY*     3.4    13.2    -      -       -      +
    425A  VAL*     3.8    24.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with PRO 349 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    246A  ILE*     5.8     3.4    -      -       +      -
    247A  ILE*     4.5    11.7    -      -       +      -
    251A  LEU*     4.0    18.3    -      -       +      +
    345A  ALA*     3.2    19.1    -      -       -      +
    346A  PHE      3.0    21.5    -      -       -      +
    348A  ALA*     1.4    86.7    -      -       +      +
    350A  VAL*     1.3    58.2    +      -       -      -
    352A  GLY*     3.5     3.3    -      -       -      +
    353A  LEU*     3.0    30.2    +      -       -      +
    392A  LEU*     3.8     2.4    -      -       -      +
    396A  THR*     3.5    38.1    -      -       +      +
    399A  GLY      5.2     1.6    -      -       -      +
    400A  SER*     5.6     2.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 350 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    251A  LEU*     4.3    14.8    -      -       +      -
    320A  LEU*     4.7     7.6    -      -       +      -
    341A  TRP*     4.2    15.7    -      -       +      -
    346A  PHE*     3.1    48.0    -      -       +      +
    347A  VAL*     2.8     8.0    +      -       -      +
    349A  PRO*     1.3    74.9    -      -       -      +
    351A  LEU*     1.3    63.1    +      -       +      +
    352A  GLY      3.0     1.1    -      -       -      -
    353A  LEU*     3.1    10.4    +      -       +      +
    354A  LEU*     2.9    28.1    +      -       +      +
    801A  HAS      3.7    36.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 351 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    341A  TRP*     4.3    15.0    -      -       +      -
    347A  VAL*     2.9    36.8    +      -       +      +
    348A  ALA      4.2     3.1    -      -       -      +
    350A  VAL*     1.3    71.3    -      -       +      +
    352A  GLY*     1.3    67.4    +      -       -      +
    354A  LEU*     2.9    34.5    +      -       +      +
    355A  GLY*     3.0    11.8    +      -       -      -
    395A  LEU*     4.6     1.1    -      -       +      -
    425A  VAL*     4.3     8.1    -      -       +      -
    426A  TRP*     3.8    50.5    -      -       +      -
    429A  PHE*     3.2    39.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 352 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    348A  ALA      3.0    17.6    +      -       -      -
    349A  PRO      3.6     5.2    -      -       -      -
    350A  VAL      3.0     0.4    -      -       -      -
    351A  LEU*     1.3    79.7    -      -       -      +
    353A  LEU*     1.3    61.4    +      -       -      +
    355A  GLY*     3.0    10.6    +      -       -      -
    356A  PHE*     3.1    10.6    +      -       -      +
    391A  SER*     4.0     3.2    +      -       -      -
    392A  LEU*     3.3    33.1    -      -       -      +
    395A  LEU*     4.0     7.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 353 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    244A  TYR*     5.7     2.5    -      -       +      -
    247A  ILE*     4.3    23.6    -      -       +      -
    251A  LEU*     5.3     1.8    -      -       +      -
    312A  THR*     6.3     1.1    -      -       +      -
    316A  VAL*     3.8    20.6    -      -       +      -
    320A  LEU*     4.5     6.5    -      -       +      -
    349A  PRO      3.0    20.1    +      -       -      +
    350A  VAL*     3.1    10.3    +      -       -      +
    352A  GLY*     1.3    73.4    -      -       -      +
    354A  LEU*     1.3    62.8    +      -       -      +
    356A  PHE*     2.9    17.5    +      -       +      +
    357A  ILE*     3.1    16.8    +      -       -      +
    392A  LEU*     3.2    22.0    -      -       +      +
    801A  HAS      3.5    61.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 354 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    341A  TRP*     6.2     1.3    -      -       +      -
    350A  VAL*     2.9    19.1    +      -       +      +
    351A  LEU*     2.9    31.6    +      -       +      +
    353A  LEU*     1.3    77.8    -      -       -      +
    355A  GLY*     1.3    57.2    +      -       -      +
    356A  PHE      3.2     0.5    +      -       -      -
    357A  ILE*     3.3    18.7    -      -       +      +
    358A  PRO*     3.1    21.5    -      -       -      +
    429A  PHE*     4.0    16.4    -      -       +      -
    433A  MET*     5.3     2.4    -      -       -      +
    801A  HAS      4.0    41.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 355 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    351A  LEU      3.0    12.0    +      -       -      -
    352A  GLY      3.0     4.9    +      -       -      -
    354A  LEU*     1.3    76.0    -      -       -      +
    356A  PHE*     1.3    60.6    +      -       -      +
    357A  ILE      3.4     0.2    -      -       -      -
    358A  PRO*     3.3     8.0    -      -       -      +
    359A  GLY      3.4     0.7    +      -       -      -
    387A  LEU*     3.1    48.2    -      -       -      +
    391A  SER*     4.5     4.9    -      -       -      -
    429A  PHE*     3.9     2.8    -      -       -      -
    433A  MET*     4.2    11.4    -      -       -      -
----------------------------------------------------------
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Residues in contact with PHE 356 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    240A  LEU*     3.8    26.5    -      -       +      -
    244A  TYR*     3.5    25.1    -      +       -      -
    309A  SER*     5.0     0.2    -      -       -      -
    352A  GLY      3.1     9.1    +      -       -      +
    353A  LEU*     2.9    17.6    +      -       +      +
    355A  GLY*     1.3    77.8    -      -       -      +
    357A  ILE*     1.3    68.5    +      -       -      +
    360A  GLY*     2.9    23.4    +      -       -      -
    387A  LEU      4.1     4.7    -      -       -      -
    388A  GLN*     3.0    47.1    -      -       +      +
    392A  LEU*     3.3    25.4    -      -       +      -
    801A  HAS      3.5    56.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 357 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    353A  LEU      3.1     7.7    +      -       -      +
    354A  LEU*     3.3    36.8    -      -       +      +
    356A  PHE*     1.3    79.0    -      -       -      +
    358A  PRO*     1.4    67.2    -      -       +      +
    360A  GLY*     3.5     5.4    +      -       -      -
    361A  ALA*     3.7     9.2    +      -       -      +
    801A  HAS      3.9    34.4    -      -       +      +
     11C  VAL*     5.7     5.6    -      -       +      -
     14C  VAL*     4.5     9.9    -      -       +      -
     15C  LEU*     3.8    37.5    -      -       +      +
     18C  THR*     4.1    22.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with PRO 358 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    354A  LEU      3.1    25.8    -      -       -      +
    355A  GLY*     3.3    13.5    -      -       -      +
    357A  ILE*     1.4    84.1    -      -       +      +
    359A  GLY*     1.3    62.2    +      -       -      +
    360A  GLY      3.1     2.2    -      -       -      -
    361A  ALA*     3.2    14.4    +      -       +      +
    362A  GLY*     3.3     8.5    +      -       -      -
    387A  LEU*     3.8    15.4    -      -       +      +
    433A  MET*     5.1    10.8    -      -       +      -
    440A  HIS*     5.0     0.9    +      -       -      -
     18C  THR*     4.6    15.0    -      -       +      -
     22C  PHE*     3.9    23.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 359 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    355A  GLY      3.4     5.9    +      -       -      -
    356A  PHE      3.1     3.2    +      -       -      -
    358A  PRO*     1.3    77.1    -      -       -      +
    360A  GLY*     1.3    59.0    +      -       -      +
    362A  GLY      3.4     2.6    +      -       -      -
    384A  HIS*     3.0    34.0    +      -       -      -
    387A  LEU*     3.5    16.7    -      -       -      +
    388A  GLN*     3.0    30.4    -      -       -      +
    440A  HIS*     5.7     0.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLY 360 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    356A  PHE      2.9    13.1    +      -       -      -
    357A  ILE      4.0     1.6    -      -       -      -
    358A  PRO      3.1     0.2    -      -       -      -
    359A  GLY*     1.3    73.4    -      -       -      +
    361A  ALA*     1.3    55.9    +      -       -      +
    362A  GLY      3.0     5.4    -      -       -      -
    363A  GLY*     3.3     1.9    +      -       -      -
    364A  ILE*     3.2    36.7    +      -       -      +
    388A  GLN*     3.4     3.3    +      -       -      -
    801A  HAS      3.7    35.4    -      -       -      +
     15C  LEU*     6.1     0.2    -      -       -      -
     19C  ILE*     5.8     0.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 361 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    357A  ILE      3.7    10.8    +      -       -      +
    358A  PRO*     3.2     6.9    +      -       +      +
    360A  GLY*     1.3    73.6    -      -       -      +
    362A  GLY*     1.3    59.7    +      -       -      +
    364A  ILE*     4.2     9.1    -      -       -      +
    365A  VAL*     3.2    21.7    +      -       -      +
     15C  LEU*     5.8     0.2    -      -       -      +
     18C  THR      3.5    26.5    -      -       -      +
     19C  ILE*     3.7    18.7    -      -       +      +
     22C  PHE*     3.0    31.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 362 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    358A  PRO      3.3     8.1    +      -       -      -
    359A  GLY      3.4     4.7    +      -       -      -
    360A  GLY      3.0     0.8    -      -       -      -
    361A  ALA*     1.3    79.7    -      -       -      +
    363A  GLY*     1.3    51.8    +      -       -      +
    365A  VAL*     3.1     7.6    +      -       -      +
    366A  ASN*     2.7    38.4    +      -       -      +
    380A  TRP*     4.0    10.6    +      -       -      -
    384A  HIS*     3.9    10.1    -      -       -      -
    440A  HIS*     5.0     1.8    -      -       -      -
     22C  PHE*     3.9    15.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLY 363 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    359A  GLY      3.5     1.4    +      -       -      -
    360A  GLY      3.3     5.3    +      -       -      -
    362A  GLY*     1.3    74.8    -      -       -      +
    364A  ILE*     1.3    54.4    +      -       -      +
    365A  VAL      3.2     0.2    -      -       -      -
    366A  ASN*     3.6     7.4    -      -       -      -
    367A  ALA*     2.7    34.7    +      -       -      +
    384A  HIS*     3.3    27.4    +      -       -      -
    801A  HAS      3.2    23.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 364 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    303A  LEU*     3.8    19.6    -      -       +      +
    306A  ALA*     4.6    23.3    -      -       +      -
    310A  LEU*     5.4     1.1    -      -       +      -
    360A  GLY      3.2    18.2    +      -       -      +
    361A  ALA*     4.7     4.3    -      -       -      +
    362A  GLY      3.3     0.2    -      -       -      -
    363A  GLY*     1.3    74.0    -      -       -      +
    365A  VAL*     1.3    55.4    -      -       -      +
    367A  ALA*     3.3    10.5    +      -       -      +
    368A  SER*     2.1    33.6    +      -       -      -
    801A  HAS      4.6    13.7    -      -       +      -
     26B  LEU*     4.9     7.2    -      -       +      -
     29B  PHE*     4.1    13.0    -      -       +      -
     19C  ILE*     3.7    40.2    -      -       +      -
     23C  TRP*     3.6    20.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 365 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    361A  ALA      3.2    16.8    -      -       -      +
    362A  GLY*     3.1    11.0    +      -       -      +
    364A  ILE*     1.3    74.8    -      -       +      +
    366A  ASN*     1.3    67.4    +      -       -      +
    368A  SER*     3.1    18.0    +      -       -      -
    371A  LEU*     3.8    18.5    -      -       +      +
    375A  VAL*     5.0     4.3    -      -       +      -
    380A  TRP*     4.1    12.8    -      -       +      +
     22C  PHE*     3.5     8.5    -      -       +      +
     23C  TRP*     3.4    44.0    -      -       +      +
     26C  VAL*     3.8    33.9    -      -       +      -
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Residues in contact with ASN 366 (chain A). Click here for Legend to table.
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                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
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    285A  PHE*     4.2     1.0    -      -       -      -
    362A  GLY      2.7    13.5    +      -       -      +
    363A  GLY*     3.2     9.5    -      -       -      +
    365A  VAL*     1.3    75.5    -      -       -      +
    367A  ALA*     1.3    58.7    +      -       -      +
    368A  SER      3.0     5.7    +      -       -      -
    372A  ASP*     3.3    26.7    -      -       -      +
    375A  VAL*     3.7     9.4    -      -       -      +
    380A  TRP*     3.5    22.2    +      -       -      -
    381A  VAL*     4.8     0.6    -      -       -      +
    384A  HIS*     3.5    28.7    +      -       -      +
    801A  HAS      3.2    62.2    +      -       -      +
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Residues in contact with ALA 367 (chain A). Click here for Legend to table.
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                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
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    285A  PHE*     3.4    11.0    -      -       -      -
    299A  SER*     3.2    20.3    +      -       -      +
    302A  THR*     3.4    23.5    -      -       +      -
    303A  LEU*     4.5     9.4    -      -       +      -
    363A  GLY      2.7    22.1    +      -       -      +
    364A  ILE*     3.5    11.0    -      -       -      +
    365A  VAL      3.1     1.4    -      -       -      -
    366A  ASN*     1.3    72.6    -      -       -      +
    368A  SER*     1.3    57.2    +      -       -      +
    369A  PHE      3.4     3.3    +      -       -      -
    801A  HAS      2.8    20.2    -      -       +      +
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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
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  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) +   -    +    +   +   +    +    -
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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