Contacts of the helix formed by residues 516 - 539 (chain B) 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 B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    225B  MET      4.8     3.0    -      -       -      +
    226B  ALA*     5.2     1.0    -      -       -      -
    229B  GLY*     3.4    27.1    -      -       -      +
    232B  TYR*     4.5     6.3    -      -       +      -
    233B  TYR*     3.7    25.1    -      -       +      +
    238B  GLU*     5.8     2.0    -      -       -      +
    246B  PHE*     3.6    25.8    -      -       +      -
    430B  ARG*     5.2     0.2    -      -       -      +
    512B  SER*     3.5    22.9    -      -       -      +
    513B  CYS      4.3     3.8    -      -       -      +
    514B  VAL      4.1     3.4    -      -       -      +
    515B  TYR*     1.3    84.6    -      -       -      +
    517B  LEU*     1.3    59.6    +      -       -      +
    518B  ALA      3.1     3.1    -      -       -      -
    519B  ALA*     3.0    30.5    +      -       +      +
    520B  ALA      4.1     0.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 517 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    229B  GLY      4.3     4.7    +      -       -      -
    230B  LEU*     3.7    29.2    -      -       +      +
    233B  TYR*     3.7    34.5    -      -       +      -
    234B  LEU*     5.9     2.2    -      -       +      -
    515B  TYR*     3.3    28.6    -      -       +      +
    516B  PRO*     1.3    82.0    -      -       -      +
    518B  ALA*     1.3    56.2    +      -       -      +
    520B  ALA*     2.9    35.9    +      -       +      +
    521B  PHE*     3.3    26.1    +      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 518 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    433B  LEU*     4.6     6.1    -      -       +      +
    437B  LEU*     3.6    22.9    -      -       +      +
    507B  TYR      4.3    14.8    -      -       -      +
    508B  VAL*     3.8     5.7    -      -       -      +
    515B  TYR*     3.7    31.8    +      -       +      +
    516B  PRO      3.1     0.4    -      -       -      -
    517B  LEU*     1.3    78.8    -      -       -      +
    519B  ALA*     1.3    57.7    +      -       -      +
    521B  PHE*     3.0    29.8    +      -       +      +
    522B  ALA      3.1     8.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 519 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    222B  LEU*     4.8     3.7    -      -       +      +
    225B  MET*     4.2    23.1    -      -       +      +
    226B  ALA*     4.1    10.3    -      -       -      +
    508B  VAL*     3.7    31.4    +      -       +      +
    512B  SER*     6.3     1.8    -      -       -      -
    516B  PRO*     3.0    16.7    +      -       +      +
    518B  ALA*     1.3    78.3    -      -       -      +
    520B  ALA*     1.3    60.8    +      -       -      +
    522B  ALA*     3.0    14.6    +      -       -      +
    523B  VAL*     3.3    15.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 520 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    226B  ALA*     3.8    25.3    -      -       +      +
    230B  LEU*     5.5     7.6    -      -       +      -
    516B  PRO      4.1     0.6    +      -       -      -
    517B  LEU*     2.9    26.5    +      -       +      +
    519B  ALA*     1.3    76.3    -      -       -      +
    521B  PHE*     1.3    63.2    +      -       +      +
    523B  VAL*     3.0    19.5    +      -       -      +
    524B  LEU*     3.0    24.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 521 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    434B  ALA*     4.2     9.0    -      -       +      -
    437B  LEU*     3.8    15.3    -      -       +      -
    438B  ILE*     3.8    38.1    -      -       +      -
    441B  GLN*     2.9    25.9    +      -       -      +
    515B  TYR*     3.8    22.4    -      +       -      -
    517B  LEU*     3.3    27.3    +      -       +      -
    518B  ALA*     3.0    26.1    +      -       +      +
    520B  ALA*     1.3    78.5    -      -       +      +
    522B  ALA*     1.3    59.3    +      -       -      +
    524B  LEU*     4.7    14.0    -      -       +      +
    525B  ASN*     3.7     7.3    +      -       -      +
    914B  UMQ      5.4     4.5    -      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 522 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    222B  LEU*     3.7    15.3    -      -       +      -
    437B  LEU*     4.8     0.6    -      -       +      +
    441B  GLN*     4.0    10.5    -      -       -      +
    504B  GLN*     3.7    16.6    -      -       +      +
    508B  VAL*     3.7    23.8    -      -       +      -
    518B  ALA      3.1     3.6    +      -       -      -
    519B  ALA      3.0    11.6    +      -       -      +
    521B  PHE*     1.3    79.0    -      -       -      +
    523B  VAL*     1.3    58.9    +      -       -      +
    525B  ASN*     3.0     6.6    +      -       -      +
    526B  ASN*     2.8    31.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 523 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    219B  THR*     4.5     6.7    -      -       +      +
    222B  LEU*     3.8    38.1    -      -       +      +
    223B  ILE*     4.1    15.3    -      -       +      +
    226B  ALA*     4.2     9.4    -      -       +      -
    519B  ALA      3.5    13.5    -      -       -      +
    520B  ALA*     3.0     7.7    +      -       -      +
    522B  ALA*     1.3    75.4    -      -       -      +
    524B  LEU*     1.3    59.5    +      -       +      +
    526B  ASN*     3.0     9.0    +      -       -      +
    527B  PHE*     3.0    58.9    +      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 524 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    520B  ALA*     3.0    22.5    +      -       +      +
    521B  PHE*     5.0    14.8    -      -       +      -
    523B  VAL*     1.3    75.9    -      -       +      +
    525B  ASN*     1.3    59.3    +      -       -      +
    527B  PHE*     4.3    19.1    +      -       +      +
    528B  THR*     3.5    19.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 525 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    441B  GLN*     3.3    49.0    -      -       -      +
    445B  GLN*     4.0    15.1    -      -       -      +
    500B  GLU*     3.8     2.0    +      -       -      +
    504B  GLN*     3.1    26.5    -      -       -      +
    521B  PHE      3.7     2.9    +      -       -      +
    522B  ALA      3.0    11.9    +      -       -      +
    524B  LEU*     1.3    77.6    -      -       -      +
    526B  ASN*     1.3    60.7    +      -       -      +
    527B  PHE      3.3     0.2    -      -       -      -
    528B  THR*     2.6    29.0    +      -       -      -
    529B  GLU*     2.9    26.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 526 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    215B  LEU*     4.1    15.7    -      -       +      +
    218B  PHE*     4.0    22.8    +      -       -      -
    219B  THR*     3.3    35.3    +      -       +      +
    222B  LEU*     4.7     4.0    -      -       -      +
    501B  LEU*     4.1     0.7    -      -       -      +
    504B  GLN*     2.9    33.5    +      -       -      +
    522B  ALA      2.8    17.8    +      -       -      +
    523B  VAL*     3.0     5.6    +      -       -      +
    525B  ASN*     1.3    76.8    +      -       -      +
    527B  PHE*     1.3    59.0    +      -       -      +
    529B  GLU*     4.0     6.1    -      -       -      +
    530B  VAL*     2.9    36.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 527 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    188B  THR*     5.0     3.3    +      -       -      +
    192B  LEU*     4.4    23.6    -      -       +      -
    219B  THR*     3.6    24.7    -      -       +      -
    220B  PHE*     4.5    11.2    -      +       -      -
    223B  ILE*     4.5     8.1    -      -       +      -
    523B  VAL*     3.0    36.8    +      -       +      +
    524B  LEU*     4.5    19.7    -      -       +      +
    526B  ASN*     1.3    76.8    -      -       -      +
    528B  THR*     1.3    59.3    +      -       +      +
    530B  VAL*     4.6     4.7    -      -       +      +
    531B  ASN*     3.7    21.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 528 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    445B  GLN*     2.6    30.6    +      -       -      +
    450B  PHE*     5.9     0.4    -      -       -      -
    524B  LEU      3.5    18.8    -      -       -      +
    525B  ASN*     2.6    16.4    +      -       -      -
    527B  PHE*     1.3    80.3    -      -       +      +
    529B  GLU*     1.3    50.6    +      -       -      +
    530B  VAL      3.3     0.4    -      -       -      -
    531B  ASN*     3.0     9.3    +      -       -      +
    532B  SER*     2.6    32.9    +      -       -      -
    908B  UMQ      4.0    31.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 529 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    211B  TYR*     4.6     1.1    -      -       -      +
    215B  LEU*     4.2    12.1    -      -       +      -
    445B  GLN*     2.6    24.9    -      -       -      +
    448B  GLU*     2.6    15.9    -      -       -      +
    500B  GLU*     2.5    24.7    -      -       -      +
    501B  LEU*     6.0     1.6    -      -       +      -
    504B  GLN*     5.5     0.4    -      -       -      +
    525B  ASN*     2.9    18.5    +      -       -      +
    526B  ASN*     3.0    13.2    +      -       -      +
    528B  THR*     1.3    76.2    +      -       -      +
    530B  VAL*     1.3    61.3    +      -       -      +
    532B  SER*     4.0     1.8    -      -       -      +
    533B  ASP*     2.8    51.8    +      -       -      +
    902B   CA      2.5     9.0    -      -       -      -
    903B   CA      2.5    24.4    -      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 530 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    186B  TRP*     4.5     3.6    +      -       -      +
    188B  THR*     4.7    13.5    -      -       +      +
    195B  GLN*     3.4    37.8    +      -       +      +
    212B  PHE*     4.1     2.0    -      -       -      -
    215B  LEU*     3.7    31.6    -      -       +      +
    216B  GLU*     5.0     2.2    -      -       -      +
    219B  THR*     4.1    13.2    -      -       +      +
    526B  ASN      2.9    20.0    +      -       -      +
    527B  PHE*     4.8     5.2    -      -       +      +
    529B  GLU*     1.3    76.0    -      -       -      +
    531B  ASN*     1.3    69.5    +      -       -      +
    534B  ALA*     3.3    18.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 531 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    186B  TRP      4.8     0.6    -      -       -      +
    187B  TYR*     3.9    13.8    -      -       +      +
    188B  THR*     3.4    43.5    +      -       -      -
    189B  ARG*     4.0    20.2    -      -       -      +
    527B  PHE      3.7    15.7    +      -       -      +
    528B  THR*     3.0     8.1    +      -       -      +
    530B  VAL*     1.3    81.1    -      -       -      +
    532B  SER*     1.3    59.3    +      -       -      +
    534B  ALA*     3.0     9.3    +      -       -      +
    535B  LEU*     2.9    25.3    +      -       -      +
    908B  UMQ      4.0    29.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with SER 532 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    445B  GLN*     3.3    31.4    +      -       -      -
    448B  GLU*     4.7     0.3    +      -       -      -
    449B  SER*     2.7    29.4    +      -       -      -
    450B  PHE*     4.4    12.0    -      -       -      -
    528B  THR      2.6    19.9    +      -       -      -
    529B  GLU      3.0     2.0    +      -       -      -
    531B  ASN*     1.3    71.8    -      -       -      +
    533B  ASP*     1.3    60.4    +      -       -      +
    535B  LEU*     3.0    10.9    +      -       -      +
    536B  LYS*     2.9    25.3    +      -       -      +
    908B  UMQ      4.9     5.4    -      -       -      -
----------------------------------------------------------
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Residues in contact with ASP 533 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    211B  TYR*     2.3    32.9    +      -       +      +
    212B  PHE*     3.7    19.7    -      -       +      -
    215B  LEU*     4.2     0.9    -      -       +      +
    448B  GLU*     2.7    30.0    -      -       -      +
    497B  ASP*     4.1     0.4    -      -       -      -
    529B  GLU*     2.8    29.4    +      -       -      +
    532B  SER*     1.3    72.9    +      -       -      +
    534B  ALA*     1.3    56.5    +      -       -      +
    536B  LYS*     2.9    19.9    +      -       -      +
    537B  MET*     2.9    31.0    +      -       -      +
    903B   CA      2.5    12.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 534 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    186B  TRP*     3.6    31.6    -      -       +      +
    187B  TYR*     3.7    17.5    -      -       +      -
    212B  PHE*     3.6    10.7    -      -       -      -
    530B  VAL      3.3    14.7    +      -       -      +
    531B  ASN      3.0    15.4    +      -       -      +
    533B  ASP*     1.3    76.8    -      -       -      +
    535B  LEU*     1.3    59.8    +      -       -      +
    537B  MET*     3.0    11.4    +      -       -      +
    538B  CYS*     3.0    19.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 535 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    187B  TYR*     3.4    19.4    +      -       -      +
    449B  SER*     4.7     3.8    -      -       -      +
    450B  PHE*     4.3    20.6    -      -       +      -
    453B  TYR*     3.8    55.6    -      -       +      -
    531B  ASN      2.9    11.3    +      -       -      +
    532B  SER      3.0     8.5    +      -       -      +
    534B  ALA*     1.3    75.3    -      -       -      +
    536B  LYS*     1.3    57.6    +      -       -      +
    538B  CYS      3.0    14.4    +      -       -      +
    539B  ARG*     3.0    25.7    +      -       +      -
    540B  VAL*     3.5     6.8    -      -       +      +
    908B  UMQ      3.9    34.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 536 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    448B  GLU*     2.5    49.3    +      -       +      +
    449B  SER*     4.1     6.7    -      -       -      -
    491B  TYR*     4.3    13.2    -      -       -      -
    497B  ASP*     2.4    40.7    +      -       -      -
    532B  SER      2.9    12.4    +      -       -      +
    533B  ASP*     2.9    21.5    +      -       -      +
    535B  LEU*     1.3    76.3    -      -       -      +
    537B  MET*     1.3    62.0    +      -       -      +
    540B  VAL*     3.9    14.1    -      -       +      -
    541B  PHE*     3.5    50.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with MET 537 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    174B  HIS*     3.9     9.7    +      -       -      -
    186B  TRP*     4.3     2.7    -      -       +      -
    204B  PHE*     3.3    36.1    -      -       +      -
    208B  ILE*     3.9    22.7    -      -       +      -
    212B  PHE*     3.9    22.4    -      -       +      -
    491B  TYR*     3.6    37.9    -      -       +      -
    533B  ASP      2.9    17.1    +      -       -      +
    534B  ALA      3.0     6.5    +      -       -      +
    536B  LYS*     1.3    86.2    -      -       -      +
    538B  CYS*     1.3    61.4    +      -       -      +
    540B  VAL      5.0     0.7    -      -       -      -
    541B  PHE*     4.8     5.6    -      -       +      +
    542B  LYS      5.0     3.3    -      -       -      +
    544B  PRO*     3.8    35.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with CYS 538 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    174B  HIS*     4.4     7.7    +      -       -      -
    179B  LEU*     3.5    36.3    -      -       +      +
    183B  GLU*     3.4    36.8    -      -       -      +
    186B  TRP*     3.5    26.7    -      -       -      -
    187B  TYR*     3.6    11.2    -      -       -      +
    204B  PHE*     4.8     0.4    -      -       -      -
    488B  MET*     5.7     1.7    -      -       -      +
    534B  ALA      3.0    18.3    +      -       -      +
    535B  LEU      3.0     2.3    +      -       -      +
    537B  MET*     1.3    82.7    -      -       -      +
    539B  ARG*     1.3    66.6    +      -       +      +
    540B  VAL      3.7     1.1    -      -       -      -
    541B  PHE      4.9     1.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 539 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    176B  SER*     5.2     7.5    +      -       -      +
    179B  LEU*     4.0    26.1    -      -       -      +
    180B  LYS*     4.6     8.3    -      -       -      +
    183B  GLU*     2.8    31.3    +      -       -      +
    187B  TYR*     5.0     0.2    -      -       -      +
    453B  TYR*     3.8    22.4    -      -       +      -
    456B  GLN*     3.3    22.0    -      -       -      +
    488B  MET*     4.5     9.3    -      -       -      +
    535B  LEU*     3.0    15.9    +      -       +      -
    538B  CYS*     1.3    78.9    +      -       +      +
    540B  VAL*     1.3    61.6    +      -       -      +
    541B  PHE      5.1     0.2    -      -       -      -
    908B  UMQ      3.4    77.7    +      -       -      +
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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