Contacts of the helix formed by residues 516 - 539 (chain A) in PDB entry 6R7X


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 PRO 516 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    225A  MET      4.8     2.9    -      -       -      +
    226A  ALA*     5.2     0.9    -      -       -      -
    229A  GLY*     3.4    27.7    -      -       -      +
    232A  TYR*     4.5     6.1    -      -       +      -
    233A  TYR*     3.7    24.9    -      -       +      +
    238A  GLU*     5.8     2.7    -      -       -      +
    246A  PHE*     3.6    26.5    -      -       +      -
    512A  SER*     3.5    22.2    -      -       -      +
    513A  CYS      4.3     4.0    -      -       -      +
    514A  VAL      4.1     3.6    -      -       -      +
    515A  TYR*     1.3    83.9    -      -       -      +
    517A  LEU*     1.3    59.4    +      -       -      +
    518A  ALA      3.1     2.9    -      -       -      -
    519A  ALA*     3.0    30.8    +      -       +      +
    520A  ALA      4.1     0.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 517 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    229A  GLY      4.7     4.7    -      -       -      -
    230A  LEU*     3.7    29.4    -      -       +      +
    233A  TYR*     3.7    35.4    -      -       +      +
    234A  LEU*     5.9     1.6    -      -       +      -
    515A  TYR*     3.3    27.8    -      -       +      +
    516A  PRO*     1.3    80.9    -      -       -      +
    518A  ALA*     1.3    56.2    +      -       -      +
    520A  ALA*     2.9    36.8    +      -       +      +
    521A  PHE*     3.3    27.0    +      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 518 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    433A  LEU*     4.6     6.7    -      -       +      +
    437A  LEU*     3.6    22.0    -      -       +      +
    507A  TYR      4.3    14.6    -      -       -      +
    508A  VAL*     3.8     6.0    -      -       -      +
    515A  TYR*     3.7    32.5    +      -       +      +
    516A  PRO      3.1     0.8    -      -       -      -
    517A  LEU*     1.3    77.0    -      -       -      +
    519A  ALA*     1.3    57.7    +      -       -      +
    521A  PHE*     3.0    30.6    +      -       +      +
    522A  ALA      3.1     9.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 519 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    222A  LEU*     4.8     3.2    -      -       +      +
    225A  MET*     4.2    23.1    -      -       +      +
    226A  ALA*     4.1    10.3    -      -       +      +
    508A  VAL*     3.7    31.8    +      -       +      +
    512A  SER*     6.3     1.3    -      -       -      -
    515A  TYR      4.9     0.2    +      -       -      -
    516A  PRO*     3.0    16.7    +      -       +      +
    518A  ALA*     1.3    78.0    -      -       -      +
    520A  ALA*     1.3    61.5    +      -       -      +
    522A  ALA*     3.0    15.1    +      -       -      +
    523A  VAL*     3.3    14.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 520 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    226A  ALA*     3.8    24.2    -      -       +      +
    230A  LEU*     5.5     7.4    -      -       +      -
    516A  PRO      4.1     0.8    +      -       -      -
    517A  LEU*     2.9    26.6    +      -       +      +
    519A  ALA*     1.3    77.2    -      -       -      +
    521A  PHE*     1.3    61.3    +      -       +      +
    523A  VAL*     3.0    19.2    +      -       -      +
    524A  LEU*     3.0    23.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 521 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    434A  ALA*     4.2     9.2    -      -       +      -
    437A  LEU*     3.8    15.7    -      -       +      -
    438A  ILE*     3.8    37.7    -      -       +      -
    441A  GLN*     2.9    25.5    -      -       -      +
    515A  TYR*     3.8    21.8    -      +       -      -
    517A  LEU*     3.3    28.7    +      -       +      -
    518A  ALA*     3.0    25.8    +      -       +      +
    520A  ALA*     1.3    79.8    -      -       +      +
    522A  ALA*     1.3    58.6    +      -       -      +
    524A  LEU*     4.7    14.7    -      -       +      +
    525A  ASN*     3.7     7.6    +      -       -      +
    713A  UMQ      5.4     4.9    -      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 522 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    222A  LEU*     3.7    16.2    -      -       +      -
    437A  LEU*     4.8     0.6    -      -       +      +
    441A  GLN*     4.0     9.6    -      -       -      +
    504A  GLN*     3.7    15.9    -      -       +      +
    508A  VAL*     3.7    24.2    -      -       +      -
    518A  ALA      3.1     3.6    +      -       -      -
    519A  ALA      3.0    11.5    +      -       -      +
    521A  PHE*     1.3    78.6    -      -       -      +
    523A  VAL*     1.3    59.2    +      -       -      +
    525A  ASN*     3.0     5.2    +      -       -      +
    526A  ASN*     2.8    31.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 523 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    219A  THR*     4.5     7.2    -      -       +      +
    222A  LEU*     3.8    37.5    -      -       +      +
    223A  ILE*     4.1    15.9    -      -       +      +
    226A  ALA*     4.2     8.5    -      -       +      -
    519A  ALA      3.5    13.7    -      -       -      +
    520A  ALA*     3.0     8.1    +      -       -      +
    522A  ALA*     1.3    74.7    -      -       -      +
    524A  LEU*     1.3    59.0    +      -       +      +
    526A  ASN*     3.0     9.3    +      -       -      +
    527A  PHE*     3.0    59.3    +      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 524 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    520A  ALA*     3.0    22.3    +      -       +      +
    521A  PHE*     5.0    15.0    -      -       +      +
    523A  VAL*     1.3    74.8    -      -       +      +
    525A  ASN*     1.3    58.8    +      -       -      +
    527A  PHE*     4.3    18.7    -      -       +      +
    528A  THR*     3.5    19.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 525 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    441A  GLN*     3.3    48.3    -      -       -      +
    445A  GLN*     4.0    15.1    -      -       -      +
    500A  GLU*     3.8     2.2    +      -       -      +
    504A  GLN*     3.1    26.1    -      -       -      +
    521A  PHE      3.7     3.3    +      -       -      +
    522A  ALA      3.0    10.9    +      -       -      +
    524A  LEU*     1.3    77.8    -      -       -      +
    526A  ASN*     1.3    62.0    +      -       -      +
    527A  PHE      3.3     0.2    -      -       -      -
    528A  THR*     2.6    28.7    +      -       -      -
    529A  GLU*     2.9    26.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 526 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    215A  LEU*     4.1    15.4    -      -       +      +
    218A  PHE*     4.0    23.2    +      -       -      -
    219A  THR*     3.3    35.5    +      -       +      +
    222A  LEU*     4.7     4.0    -      -       -      +
    501A  LEU*     4.1     0.9    -      -       -      +
    504A  GLN*     2.9    33.2    +      -       -      +
    522A  ALA      2.8    17.9    +      -       -      +
    523A  VAL*     3.0     5.0    +      -       -      +
    525A  ASN*     1.3    77.1    +      -       -      +
    527A  PHE*     1.3    60.1    +      -       -      +
    529A  GLU*     3.0     6.8    +      -       -      +
    530A  VAL*     2.9    36.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 527 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    188A  THR*     5.0     4.2    +      -       -      +
    192A  LEU*     4.4    23.3    -      -       +      -
    219A  THR*     3.6    24.0    -      -       +      -
    220A  PHE*     4.5    11.9    -      +       -      -
    223A  ILE*     4.5     7.9    -      -       +      -
    523A  VAL*     3.0    38.1    +      -       +      +
    524A  LEU*     4.5    20.6    -      -       +      +
    525A  ASN      3.3     0.2    -      -       -      -
    526A  ASN*     1.3    75.7    -      -       -      +
    528A  THR*     1.3    58.8    +      -       +      +
    530A  VAL*     4.6     4.9    -      -       +      +
    531A  ASN*     3.7    21.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 528 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    445A  GLN*     2.6    31.0    +      -       -      +
    450A  PHE*     6.2     0.2    -      -       -      -
    524A  LEU      3.5    18.8    -      -       -      +
    525A  ASN*     2.6    16.0    +      -       -      -
    527A  PHE*     1.3    79.6    -      -       +      +
    529A  GLU*     1.3    49.8    +      -       -      +
    530A  VAL      3.3     0.4    -      -       -      -
    531A  ASN*     3.0     9.2    +      -       -      +
    532A  SER*     2.6    33.6    +      -       -      -
    707A  UMQ      4.0    31.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 529 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    211A  TYR*     4.6     1.3    -      -       -      +
    215A  LEU*     4.2    12.8    -      -       +      -
    445A  GLN*     2.6    24.8    -      -       -      +
    448A  GLU*     2.6    16.6    -      -       -      +
    500A  GLU*     2.5    24.9    -      -       -      +
    501A  LEU*     6.0     1.6    -      -       +      -
    504A  GLN*     5.5     0.9    -      -       -      +
    525A  ASN*     2.9    19.8    +      -       -      +
    526A  ASN*     3.0    12.7    +      -       -      +
    528A  THR*     1.3    75.6    +      -       -      +
    530A  VAL*     1.3    61.9    +      -       -      +
    532A  SER*     4.0     1.3    -      -       -      +
    533A  ASP*     2.8    51.8    +      -       -      +
    701A   CA      2.5     9.0    -      -       -      -
    702A   CA      2.5    23.6    -      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 530 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    186A  TRP*     4.5     4.0    +      -       -      +
    188A  THR*     4.7    15.0    -      -       +      +
    195A  GLN*     3.4    35.8    +      -       +      +
    212A  PHE*     4.1     1.8    -      -       -      -
    215A  LEU*     3.7    31.4    -      -       +      +
    216A  GLU*     5.0     2.7    -      -       -      +
    219A  THR*     4.1    13.2    -      -       +      +
    526A  ASN      2.9    19.6    +      -       -      +
    527A  PHE*     4.8     6.1    -      -       +      +
    529A  GLU*     1.3    76.3    -      -       -      +
    531A  ASN*     1.3    67.0    +      -       -      +
    534A  ALA*     3.3    18.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 531 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    186A  TRP      4.8     0.4    -      -       -      +
    187A  TYR*     3.9    13.4    -      -       +      +
    188A  THR*     3.4    42.5    +      -       -      -
    189A  ARG*     4.0    19.8    -      -       -      +
    527A  PHE      3.7    16.2    +      -       -      +
    528A  THR*     3.0     7.8    +      -       -      +
    530A  VAL*     1.3    82.5    -      -       -      +
    532A  SER*     1.3    58.8    +      -       -      +
    534A  ALA*     3.0     9.3    +      -       -      +
    535A  LEU*     2.9    25.8    +      -       -      +
    707A  UMQ      4.0    30.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with SER 532 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    445A  GLN*     3.3    32.3    +      -       -      -
    448A  GLU*     4.7     0.2    +      -       -      -
    449A  SER*     2.7    29.1    +      -       -      -
    450A  PHE*     4.4    12.3    -      -       -      -
    528A  THR      2.6    18.9    +      -       -      -
    529A  GLU*     3.0     2.4    +      -       -      -
    531A  ASN*     1.3    72.3    -      -       -      +
    533A  ASP*     1.3    59.9    +      -       -      +
    535A  LEU*     3.0    11.7    +      -       -      +
    536A  LYS*     2.9    24.1    +      -       -      +
    707A  UMQ      4.9     4.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with ASP 533 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    211A  TYR*     2.3    33.2    +      -       +      +
    212A  PHE*     3.7    19.5    -      -       +      -
    215A  LEU*     4.2     0.8    -      -       +      +
    448A  GLU*     2.7    30.0    -      -       -      +
    497A  ASP*     4.1     0.4    -      -       -      -
    529A  GLU*     2.8    28.7    +      -       -      +
    532A  SER*     1.3    74.4    +      -       -      +
    534A  ALA*     1.3    57.8    +      -       -      +
    536A  LYS*     2.9    20.7    +      -       -      +
    537A  MET*     2.9    30.9    +      -       +      +
    702A   CA      2.5    10.6    -      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 534 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    186A  TRP*     3.6    31.9    -      -       +      +
    187A  TYR*     3.7    18.4    -      -       +      -
    212A  PHE*     3.6    10.9    -      -       +      -
    530A  VAL      3.3    15.3    +      -       -      +
    531A  ASN      3.0    14.1    +      -       -      +
    533A  ASP*     1.3    78.6    -      -       -      +
    535A  LEU*     1.3    59.4    +      -       -      +
    537A  MET*     3.0    11.4    +      -       -      +
    538A  CYS*     3.0    19.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 535 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    187A  TYR*     3.4    18.5    +      -       -      +
    449A  SER*     4.7     3.6    -      -       -      +
    450A  PHE*     4.3    21.3    -      -       +      -
    453A  TYR*     3.8    55.4    -      -       +      -
    531A  ASN      2.9    11.1    +      -       -      +
    532A  SER      3.0     8.5    +      -       -      +
    534A  ALA*     1.3    73.7    -      -       -      +
    536A  LYS*     1.3    59.2    +      -       -      +
    538A  CYS      3.0    14.8    +      -       -      +
    539A  ARG*     3.0    24.2    +      -       +      -
    540A  VAL*     3.5     7.5    -      -       +      +
    707A  UMQ      3.9    34.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 536 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    448A  GLU*     2.5    46.8    +      -       +      +
    449A  SER*     4.1     6.1    -      -       -      -
    491A  TYR*     4.3    13.2    -      -       -      -
    497A  ASP*     2.4    40.3    +      -       -      -
    532A  SER      2.9    12.7    +      -       -      +
    533A  ASP*     2.9    21.7    +      -       -      +
    535A  LEU*     1.3    76.5    -      -       -      +
    537A  MET*     1.3    62.2    +      -       -      +
    540A  VAL*     3.9    14.1    -      -       +      -
    541A  PHE*     3.5    50.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with MET 537 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    174A  HIS*     4.0     9.7    +      -       -      -
    186A  TRP*     4.3     2.9    -      -       +      -
    204A  PHE*     3.3    36.1    -      -       +      -
    208A  ILE*     3.9    22.9    -      -       +      -
    212A  PHE*     3.9    22.7    -      -       +      -
    491A  TYR*     3.6    37.5    -      -       +      -
    533A  ASP*     2.9    18.1    +      -       +      +
    534A  ALA      3.0     7.1    +      -       -      +
    536A  LYS*     1.3    85.5    -      -       -      +
    538A  CYS*     1.3    60.0    +      -       -      +
    540A  VAL      5.0     0.2    -      -       -      -
    541A  PHE*     4.8     5.7    -      -       +      +
    542A  LYS      5.0     3.6    -      -       -      +
    544A  PRO*     3.8    33.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with CYS 538 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    174A  HIS*     4.4     7.3    +      -       -      -
    179A  LEU*     3.5    35.3    -      -       -      +
    183A  GLU*     3.4    36.8    -      -       -      +
    186A  TRP*     3.5    27.1    -      -       -      -
    187A  TYR*     3.6    11.2    -      -       -      +
    204A  PHE*     4.8     0.7    -      -       -      -
    488A  MET*     5.7     1.9    -      -       -      +
    534A  ALA      3.0    18.4    +      -       -      +
    535A  LEU      3.0     2.3    +      -       -      +
    537A  MET*     1.3    82.5    -      -       -      +
    539A  ARG*     1.3    67.4    +      -       +      +
    540A  VAL      3.7     0.9    -      -       -      -
    541A  PHE      4.9     2.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 539 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    176A  SER*     5.2     7.7    +      -       -      +
    179A  LEU*     4.0    25.2    -      -       -      +
    180A  LYS*     4.6     8.5    -      -       -      +
    183A  GLU*     2.8    33.0    +      -       -      +
    453A  TYR*     3.8    22.4    -      -       +      -
    456A  GLN*     3.3    21.7    -      -       -      +
    488A  MET*     4.5     9.8    -      -       -      +
    535A  LEU*     3.0    16.9    +      -       +      -
    538A  CYS*     1.3    80.0    +      -       +      +
    540A  VAL*     1.3    62.1    +      -       -      +
    541A  PHE      5.1     0.2    -      -       -      -
    707A  UMQ      3.4    76.7    +      -       -      +
----------------------------------------------------------
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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