Contacts of the helix formed by residues 568 - 593 (chain B) in PDB entry 3U1K


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 ILE 568 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    224B  SER*     3.7    21.0    +      -       -      +
    226B  ILE*     4.1    22.9    -      -       +      -
    245B  ILE*     5.3     1.1    -      -       +      -
    246B  LYS*     4.3    30.5    -      -       +      +
    249B  VAL*     3.7    29.6    -      -       +      -
    566B  ILE      3.7     1.0    +      -       -      -
    567B  PRO*     1.3    72.4    -      -       -      +
    569B  LYS*     1.3    64.5    +      -       -      +
    571B  VAL*     3.1     3.5    +      -       -      +
    572B  MET*     3.0    41.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 569 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    527B  TYR*     3.4    30.9    +      -       -      +
    567B  PRO*     3.1    14.6    -      -       +      +
    568B  ILE*     1.3    78.6    -      -       -      +
    570B  ILE*     1.3    64.4    +      -       -      +
    572B  MET*     3.4     9.0    +      -       -      +
    573B  GLU*     3.0    47.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 570 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    513B  LEU*     4.0    15.5    -      -       +      -
    524B  ILE*     3.9    15.3    -      -       +      -
    527B  TYR*     3.9    43.1    -      -       +      -
    529B  LEU*     3.8    25.7    -      -       +      +
    543B  MET*     5.2     1.6    -      -       +      -
    566B  ILE*     4.2    17.3    -      -       +      -
    567B  PRO*     3.2    31.9    +      -       +      +
    568B  ILE      3.2     0.6    -      -       -      -
    569B  LYS*     1.3    84.7    -      -       -      +
    571B  VAL*     1.3    57.5    +      -       -      +
    573B  GLU*     3.5     4.9    +      -       -      -
    574B  ALA*     3.0    25.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 571 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    226B  ILE*     3.6    31.0    -      -       +      -
    229B  LEU*     4.1    15.7    -      -       +      -
    245B  ILE*     4.4     1.1    -      -       +      -
    543B  MET*     6.1     0.2    -      -       -      -
    545B  PHE*     4.0    15.7    -      -       +      -
    561B  ILE*     5.3     0.7    -      -       +      -
    566B  ILE*     3.8    22.9    -      -       +      -
    567B  PRO      3.6    15.0    -      -       -      +
    568B  ILE      3.1     3.2    +      -       -      +
    570B  ILE*     1.3    74.6    -      -       -      +
    572B  MET*     1.3    85.0    +      -       +      +
    574B  ALA*     3.4     6.1    +      -       -      +
    575B  ILE*     3.0    39.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with MET 572 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    238B  GLN*     5.5     0.5    +      -       -      -
    242B  CYS*     3.6    32.6    -      -       -      +
    245B  ILE*     3.9    29.6    -      -       +      -
    246B  LYS*     4.0    22.9    -      -       -      +
    568B  ILE*     3.0    30.9    +      -       +      +
    569B  LYS*     3.7     9.0    -      -       -      +
    571B  VAL*     1.3   107.4    -      -       +      +
    573B  GLU*     1.3    63.1    +      -       +      +
    575B  ILE*     3.3    11.2    +      -       +      +
    576B  GLN*     3.1    22.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 573 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    527B  TYR*     2.5    40.8    +      -       -      -
    529B  LEU*     3.6    14.1    -      -       +      +
    569B  LYS*     3.0    35.9    +      -       +      +
    570B  ILE*     3.9     1.1    -      -       -      +
    572B  MET*     1.3    74.1    -      -       +      +
    574B  ALA*     1.3    59.9    +      -       -      +
    576B  GLN*     3.3     6.3    +      -       -      +
    577B  GLN*     2.9    31.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 574 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    511B  ILE*     3.9    12.9    -      -       +      +
    529B  LEU*     3.6    11.8    -      -       +      +
    543B  MET*     4.0    26.7    -      -       +      -
    545B  PHE*     4.2    12.8    -      -       +      -
    570B  ILE      3.0    18.5    +      -       -      +
    571B  VAL*     3.6     8.5    -      -       -      +
    572B  MET      3.3     0.2    -      -       -      -
    573B  GLU*     1.3    76.6    -      -       -      +
    575B  ILE*     1.3    57.3    +      -       -      +
    577B  GLN*     3.4     1.7    +      -       -      -
    578B  ALA*     2.8    32.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 575 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    238B  GLN*     3.9    28.0    -      -       +      +
    241B  PHE*     4.2    10.3    -      -       +      -
    242B  CYS*     3.7    18.8    -      -       -      -
    245B  ILE*     3.6    30.7    -      -       +      -
    545B  PHE*     3.6    21.3    -      -       +      -
    547B  ILE*     4.3     9.1    -      -       +      +
    554B  ILE*     4.2    14.6    -      -       +      -
    571B  VAL*     3.0    21.3    +      -       +      +
    572B  MET*     3.5     9.4    -      -       +      +
    573B  GLU      3.3     0.2    -      -       -      -
    574B  ALA*     1.3    75.4    -      -       -      +
    576B  GLN*     1.3    57.4    +      -       -      +
    578B  ALA*     3.3     7.2    +      -       -      +
    579B  SER*     2.9    26.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLN 576 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    238B  GLN*     2.8    37.7    +      -       -      +
    572B  MET      3.1    12.9    +      -       -      +
    573B  GLU*     3.8     8.7    -      -       -      +
    575B  ILE*     1.3    75.6    -      -       -      +
    577B  GLN*     1.3    60.0    +      -       -      +
    579B  SER*     2.9    28.2    +      -       -      -
    580B  VAL*     3.1    24.7    +      -       +      +
    583B  LYS*     6.1     1.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 577 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    364B  LEU*     3.6     2.4    +      -       -      +
    365B  THR*     4.1    18.0    -      -       +      +
    511B  ILE*     4.5     4.8    -      -       +      +
    529B  LEU*     3.1    47.4    +      -       -      +
    530B  LEU      3.7     1.2    -      -       -      -
    531B  THR*     2.8    40.7    -      -       +      +
    573B  GLU      2.9    17.0    +      -       -      +
    574B  ALA*     3.9     4.7    -      -       -      +
    576B  GLN*     1.3    77.1    -      -       -      +
    578B  ALA*     1.3    62.0    +      -       -      +
    580B  VAL*     3.4    12.2    +      -       +      +
    581B  ALA*     3.3    20.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 578 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    509B  VAL*     3.9     8.5    -      -       +      +
    511B  ILE*     3.7    21.2    -      -       +      +
    547B  ILE*     3.2    34.8    -      -       +      -
    574B  ALA      2.8    19.3    +      -       -      +
    575B  ILE      3.6     4.3    -      -       -      +
    577B  GLN*     1.3    76.5    -      -       -      +
    579B  SER*     1.3    58.2    +      -       -      +
    581B  ALA*     3.3     1.5    +      -       -      +
    582B  LYS*     2.8    32.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 579 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    238B  GLN*     3.4    26.3    +      -       -      -
    575B  ILE      2.9     9.6    +      -       -      -
    576B  GLN*     2.9    19.9    +      -       -      -
    578B  ALA*     1.3    77.9    -      -       -      +
    580B  VAL*     1.3    61.4    +      -       -      +
    582B  LYS*     3.4    18.1    +      -       -      +
    583B  LYS*     3.2    46.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 580 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    365B  THR*     5.6     9.0    -      -       -      +
    531B  THR*     6.5     0.7    -      -       +      -
    576B  GLN*     3.1    32.7    +      -       +      +
    577B  GLN*     3.4    10.7    +      -       +      +
    578B  ALA      3.3     0.2    -      -       -      -
    579B  SER*     1.3    78.2    -      -       -      +
    581B  ALA*     1.3    64.4    +      -       +      +
    583B  LYS*     3.4    10.1    +      -       -      +
    584B  GLU*     3.1    41.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 581 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    365B  THR      5.4     1.3    -      -       -      +
    367B  LEU*     3.8    14.1    -      -       +      +
    509B  VAL*     4.2    13.5    -      -       +      -
    531B  THR*     4.0    23.1    -      -       +      +
    577B  GLN      3.3    10.7    +      -       -      +
    578B  ALA*     3.7     6.7    -      -       -      +
    579B  SER      3.3     0.2    -      -       -      -
    580B  VAL*     1.3    81.8    -      -       +      +
    582B  LYS*     1.3    63.8    +      -       -      +
    584B  GLU*     3.2    13.4    +      -       -      +
    585B  ILE*     2.9    29.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 582 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    507B  ALA*     3.8    15.7    -      -       +      +
    508B  GLY*     5.7     0.7    -      -       -      -
    509B  VAL*     4.6     6.2    -      -       +      +
    547B  ILE      5.7     1.6    -      -       -      +
    548B  ALA*     4.4     3.1    -      -       -      -
    549B  GLY*     3.7    24.8    -      -       -      +
    550B  THR      2.9    27.7    +      -       -      +
    551B  ASN*     5.1     1.5    -      -       -      +
    553B  GLY      3.0    22.2    +      -       -      +
    554B  ILE*     4.4    10.1    -      -       -      +
    578B  ALA      2.8    16.5    +      -       -      +
    579B  SER*     3.6    20.9    +      -       -      +
    580B  VAL      3.3     0.2    -      -       -      -
    581B  ALA*     1.3    75.3    -      -       -      +
    583B  LYS*     1.3    64.0    +      -       -      +
    585B  ILE*     3.2    13.1    +      -       -      +
    586B  LEU*     2.9    38.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 583 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    551B  ASN*     3.6    37.9    -      -       +      -
    576B  GLN*     6.1     0.8    -      -       -      +
    579B  SER*     3.2    33.5    +      -       -      +
    580B  VAL*     3.8     7.1    -      -       -      +
    582B  LYS*     1.3    80.4    -      -       -      +
    584B  GLU*     1.3    65.6    +      -       +      +
    586B  LEU*     3.4     9.1    +      -       -      +
    587B  GLN*     3.0    29.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 584 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    365B  THR      4.8     8.1    -      -       -      +
    367B  LEU*     3.5    30.7    +      -       +      +
    580B  VAL*     3.1    35.2    +      -       +      +
    581B  ALA*     3.5    10.0    -      -       -      +
    583B  LYS*     1.3    78.0    -      -       +      +
    585B  ILE*     1.3    62.2    +      -       -      +
    587B  GLN*     3.2     8.5    +      -       -      +
    588B  ILE*     3.2    28.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 585 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    367B  LEU*     3.7    30.5    -      -       +      -
    370B  VAL*     5.0     9.6    -      -       +      -
    386B  PHE*     4.1    11.4    -      -       +      -
    388B  ARG*     4.5    10.3    -      -       -      +
    489B  CYS*     3.9     8.7    -      -       -      -
    507B  ALA*     3.7    15.9    -      -       +      -
    508B  GLY      3.4    25.6    -      -       -      +
    509B  VAL*     4.0    11.0    -      -       +      -
    581B  ALA      2.9    19.8    +      -       -      +
    582B  LYS*     3.2     8.3    +      -       -      +
    584B  GLU*     1.3    77.0    -      -       -      +
    586B  LEU*     1.3    58.0    +      -       -      +
    588B  ILE*     3.1     9.9    +      -       -      +
    589B  MET*     2.8    38.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 586 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    505B  ALA*     3.7    25.8    -      -       +      +
    506B  VAL      3.7     8.1    -      -       -      +
    507B  ALA*     3.5    28.0    -      -       +      +
    549B  GLY      4.5     0.2    -      -       -      +
    550B  THR*     3.7     7.4    -      -       -      -
    551B  ASN*     3.4    42.2    -      -       +      +
    582B  LYS*     2.9    30.2    +      -       +      +
    583B  LYS*     3.8     7.4    -      -       -      +
    584B  GLU      3.3     0.2    -      -       -      -
    585B  ILE*     1.3    76.0    -      -       -      +
    587B  GLN*     1.3    57.7    +      -       -      +
    589B  MET*     3.7     8.2    -      -       +      +
    590B  ASN*     2.9    44.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 587 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    583B  LYS*     3.0    19.9    +      -       +      +
    584B  GLU*     3.5    11.2    -      -       -      +
    585B  ILE      3.2     0.2    -      -       -      -
    586B  LEU*     1.3    76.6    -      -       +      +
    588B  ILE*     1.3    63.5    +      -       +      +
    590B  ASN*     3.6    12.5    +      -       -      +
    591B  LYS*     3.4    45.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 588 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    367B  LEU*     4.8     7.9    -      -       +      -
    368B  ARG      5.7     1.1    -      -       -      +
    369B  ASN*     6.3     0.2    -      -       -      -
    370B  VAL*     3.4    52.9    -      -       +      +
    371B  SER*     5.5     0.2    -      -       -      -
    372B  CYS*     4.7     4.7    -      -       -      -
    584B  GLU*     3.2    18.6    +      -       +      +
    585B  ILE*     3.1     8.6    +      -       -      +
    587B  GLN*     1.3    76.0    -      -       +      +
    589B  MET*     1.3    65.1    +      -       -      +
    591B  LYS*     3.1    26.6    +      -       +      +
    592B  THR*     3.7     6.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with MET 589 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    370B  VAL*     5.6     0.2    -      -       +      -
    372B  CYS*     4.2    11.7    -      -       -      -
    386B  PHE*     4.1    18.4    -      -       +      -
    489B  CYS*     3.5    31.6    -      -       -      +
    492B  SER*     3.8    12.3    -      -       -      +
    493B  LEU*     3.9    22.0    -      -       +      +
    505B  ALA*     4.7     4.5    -      -       +      -
    506B  VAL      3.4    25.4    -      -       -      +
    507B  ALA*     4.0     6.7    -      -       -      -
    585B  ILE*     2.8    38.4    +      -       -      +
    586B  LEU*     3.7    13.2    -      -       +      +
    588B  ILE*     1.3    74.6    -      -       +      +
    590B  ASN*     1.3    60.8    +      -       -      +
    592B  THR*     3.1    19.4    +      -       -      -
    593B  ILE      3.1    14.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 590 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    496B  MET*     5.2     0.2    -      -       -      +
    505B  ALA*     4.0    21.3    -      -       -      +
    586B  LEU*     2.9    33.8    +      -       -      +
    587B  GLN*     4.0    14.4    +      -       -      +
    588B  ILE      3.2     0.4    -      -       -      -
    589B  MET*     1.3    74.9    -      -       -      +
    591B  LYS*     1.3    64.5    +      -       -      +
    592B  THR      3.2     0.4    +      -       -      -
    593B  ILE*     3.4    16.6    +      -       -      +
    594B  SER*     3.3    36.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 591 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     43A  MET      5.7     1.0    +      -       -      -
     61A  GLY      5.6     0.2    -      -       -      +
     65A  ARG*     3.3    29.3    +      -       -      +
    587B  GLN*     3.4    38.8    +      -       -      +
    588B  ILE*     3.1    16.2    +      -       +      +
    590B  ASN*     1.3    78.6    -      -       -      +
    592B  THR*     1.3    60.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 592 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     43A  MET*     3.8    18.5    +      -       -      -
     44A  ALA*     4.2     6.0    +      -       +      -
     61A  GLY      5.0     3.6    -      -       -      +
     65A  ARG*     4.8     5.4    +      -       -      +
    372B  CYS*     3.5    47.2    +      -       +      +
    373B  GLU*     4.3     8.5    -      -       -      -
    374B  VAL*     4.4    19.4    -      -       +      +
    493B  LEU*     5.0     0.7    -      -       +      -
    588B  ILE      3.7     3.9    +      -       -      -
    589B  MET      3.1    10.1    +      -       -      -
    590B  ASN      4.3     0.2    -      -       -      -
    591B  LYS*     1.3    81.4    -      -       -      +
    593B  ILE*     1.3    61.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 593 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     43A  MET*     3.7    32.1    -      -       +      +
    374B  VAL*     4.2    19.3    -      -       +      -
    493B  LEU*     3.6    31.4    -      -       +      +
    496B  MET*     3.7    29.5    -      -       +      +
    497B  ASP*     3.7    19.1    -      -       -      +
    589B  MET      3.1    12.4    +      -       -      +
    590B  ASN*     3.4    11.1    -      -       -      +
    591B  LYS      3.7     0.2    -      -       -      -
    592B  THR*     1.3    79.3    -      -       +      +
    594B  SER*     1.3    60.5    +      -       -      +
    595B  LYS      3.3    24.7    -      -       -      +
    597B  ARG*     5.0     0.4    -      -       -      +
----------------------------------------------------------
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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