Contacts of the helix formed by residues 555 - 580 (chain D) in PDB entry 1P93


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 SER 555 (chain D).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    553D  PRO      3.8     1.1    +      -       -      -
    554D  ASP*     1.3    79.0    -      -       -      +
    556D  THR*     1.3    65.7    +      -       -      +
    557D  TRP*     3.1    31.3    +      -       -      -
    558D  ARG*     3.3    23.5    -      -       -      +
    559D  ILE*     2.9    31.3    +      -       -      +
    636D  LEU*     4.8     2.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 556 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    555D  SER*     1.3    70.5    +      -       -      +
    557D  TRP*     1.3    68.0    +      -       +      +
    559D  ILE*     2.9    14.4    +      -       -      +
    560D  MET*     3.1    29.3    +      -       +      +
    636D  LEU*     3.8     9.1    -      -       -      +
    637D  PRO*     3.1    47.7    +      -       -      +
    638D  ASP*     4.7     7.2    -      -       +      +
    639D  MET*     4.1    18.4    -      -       +      -
    642D  GLN*     5.4     0.2    -      -       -      +
    747D  ILE*     5.2     4.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with TRP 557 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    555D  SER*     3.1    25.4    +      -       -      -
    556D  THR*     1.3    80.4    -      -       +      +
    558D  ARG*     1.3    75.2    +      -       +      +
    559D  ILE      3.3     0.3    +      -       -      -
    560D  MET*     4.1     0.4    -      -       -      -
    561D  THR*     2.7    44.0    +      -       +      -
    745D  MET      3.5    20.6    -      -       -      +
    746D  SER*     2.7    43.3    -      -       -      -
    747D  ILE*     3.6    18.6    -      -       +      +
    748D  GLU*     6.3     0.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 558 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    548D  TYR*     2.6    51.6    +      -       +      +
    549D  ASP*     4.3     5.7    -      -       -      +
    550D  SER      3.6    11.5    +      -       -      +
    552D  VAL*     2.2    57.2    +      -       -      +
    553D  PRO      3.0    20.0    +      -       -      -
    554D  ASP*     3.8     4.4    +      -       -      +
    555D  SER*     3.2    26.6    +      -       -      +
    556D  THR      3.1     0.2    -      -       -      -
    557D  TRP*     1.3   103.2    -      -       +      +
    559D  ILE*     1.3    52.6    +      -       -      +
    561D  THR*     3.9     4.0    -      -       -      -
    562D  THR*     2.7    27.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 559 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    548D  TYR*     3.5    23.1    -      -       +      +
    554D  ASP*     4.3     9.2    -      -       -      +
    555D  SER      2.9    27.2    +      -       -      +
    556D  THR*     2.9     8.0    +      -       -      +
    558D  ARG*     1.3    74.4    -      -       -      +
    560D  MET*     1.3    71.2    +      -       -      +
    561D  THR      3.2     1.6    -      -       -      -
    562D  THR*     2.9    19.3    +      -       -      -
    563D  LEU*     3.0    33.8    +      -       +      +
    627D  LEU*     5.5     9.6    -      -       +      -
    629D  ILE*     5.9     5.4    -      -       +      -
    633D  ARG*     4.8     9.9    -      -       +      +
    636D  LEU*     3.5    30.7    -      -       +      -
    639D  MET*     4.3    11.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with MET 560 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    556D  THR*     3.1    28.0    +      -       +      +
    559D  ILE*     1.3    78.7    -      -       -      +
    561D  THR*     1.3    53.2    +      -       -      +
    563D  LEU*     2.8    22.5    +      -       +      +
    564D  ASN*     2.6    38.1    +      -       -      -
    639D  MET*     4.9     8.5    -      -       -      +
    642D  GLN*     3.0    43.7    -      -       -      +
    739D  THR*     5.6     2.0    -      -       +      -
    747D  ILE*     3.3    34.5    -      -       +      -
   4999D  DEX      3.1    33.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 561 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    557D  TRP*     2.7    34.2    +      -       +      -
    558D  ARG      3.9     6.3    -      -       -      -
    559D  ILE      3.2     0.2    -      -       -      -
    560D  MET*     1.3    78.1    -      -       -      +
    562D  THR*     1.3    59.6    +      -       -      +
    564D  ASN*     3.7     1.1    +      -       -      +
    565D  MET*     3.0    38.7    +      -       +      +
    747D  ILE*     3.4     5.9    -      -       -      -
    748D  GLU*     3.1    52.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with THR 562 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    546D  ALA*     4.5    10.8    -      -       +      +
    547D  GLY      4.7     1.6    -      -       -      -
    548D  TYR*     4.0    44.0    -      -       +      +
    558D  ARG      2.7    21.0    +      -       -      -
    559D  ILE*     2.9    10.2    +      -       -      -
    561D  THR*     1.3    75.6    -      -       -      +
    563D  LEU*     1.3    54.8    +      -       -      +
    565D  MET*     2.9    12.3    +      -       +      +
    566D  LEU*     2.7    33.8    +      -       -      +
    627D  LEU*     5.0     9.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 563 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    559D  ILE*     3.0    30.3    +      -       +      +
    560D  MET*     2.8    21.7    +      -       +      +
    562D  THR*     1.3    77.4    -      -       -      +
    564D  ASN*     1.3    52.4    +      -       -      +
    566D  LEU*     3.0     8.5    +      -       +      +
    567D  GLY*     2.5    36.2    +      -       -      -
    623D  PHE*     3.9    44.0    -      -       +      -
    627D  LEU*     3.7    30.1    -      -       +      -
    629D  ILE*     5.5     3.6    -      -       +      -
    639D  MET*     6.5     0.4    -      -       -      -
   4999D  DEX      3.7    25.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 564 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    560D  MET      2.6    24.2    +      -       -      +
    561D  THR      3.9     1.3    -      -       -      +
    563D  LEU*     1.3    70.9    -      -       -      +
    565D  MET*     1.3    56.4    +      -       -      +
    568D  GLY      2.9    21.8    +      -       -      -
    747D  ILE*     3.4    21.2    -      -       -      +
    748D  GLU      3.0    28.3    +      -       -      +
    749D  PHE*     3.8    13.2    -      -       +      -
    750D  PRO*     3.0    26.5    -      -       +      +
    753D  LEU*     3.4     2.7    -      -       +      +
   4999D  DEX      2.9    48.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with MET 565 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    546D  ALA      6.1     0.9    -      -       -      +
    561D  THR*     3.0    35.4    +      -       +      +
    562D  THR*     2.9    16.9    +      -       +      +
    564D  ASN*     1.3    77.7    -      -       -      +
    566D  LEU*     1.3    59.9    +      -       -      +
    568D  GLY*     3.7     1.4    +      -       -      -
    569D  ARG*     3.2    31.0    +      -       -      +
    748D  GLU*     4.5     5.2    -      -       +      +
    749D  PHE      3.6     7.2    -      -       -      +
    750D  PRO*     3.1    49.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 566 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    544D  LEU*     3.6    25.6    -      -       +      +
    545D  TYR      4.1     7.4    -      -       -      +
    546D  ALA*     4.5    10.5    +      -       +      +
    562D  THR      2.7    11.3    +      -       -      +
    563D  LEU*     3.4    15.0    -      -       +      +
    565D  MET*     1.3    75.1    -      -       -      +
    567D  GLY*     1.3    69.1    +      -       -      +
    569D  ARG*     2.8    41.7    +      -       -      +
    570D  GLN*     2.9    25.2    +      -       -      +
    623D  PHE*     3.8    32.8    -      -       +      +
    624D  ALA*     3.9    13.9    -      -       +      -
    627D  LEU*     6.2     0.2    -      -       +      -
   4999D  DEX      4.5     7.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 567 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    563D  LEU      2.5    20.2    +      -       -      -
    564D  ASN      4.1     0.9    -      -       -      -
    566D  LEU*     1.3    71.5    -      -       -      +
    568D  GLY*     1.3    53.4    +      -       -      +
    570D  GLN*     2.6    28.5    +      -       -      +
    571D  VAL*     2.9    18.0    +      -       -      +
    604D  MET*     4.6     0.7    -      -       -      +
    753D  LEU*     4.5     2.2    -      -       -      -
   4999D  DEX      3.4    35.4    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLY 568 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    564D  ASN      2.9    20.5    +      -       -      -
    565D  MET      4.0     1.8    -      -       -      -
    566D  LEU      3.1     0.4    -      -       -      -
    567D  GLY*     1.3    76.1    -      -       -      +
    569D  ARG*     1.3    58.9    +      -       -      +
    571D  VAL*     3.6     8.2    +      -       -      +
    572D  ILE*     3.3    22.0    +      -       -      +
    750D  PRO*     3.8    17.7    -      -       -      -
    752D  MET*     3.9     7.5    -      -       -      +
    753D  LEU*     3.9    15.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 569 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    544D  LEU*     3.2    47.0    -      -       +      +
    545D  TYR      3.1    27.1    +      -       -      +
    546D  ALA      3.7     9.3    +      -       -      -
    565D  MET*     3.2    17.8    +      -       -      +
    566D  LEU*     2.8    28.6    +      -       -      +
    568D  GLY*     1.3    72.6    -      -       -      +
    570D  GLN*     1.3    62.9    +      -       -      +
    571D  VAL      3.3     0.2    -      -       -      -
    572D  ILE*     3.5    17.5    -      -       +      +
    573D  ALA*     3.2    19.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 570 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    543D  VAL*     5.3     1.4    -      -       -      -
    544D  LEU*     4.0    26.7    +      -       +      +
    566D  LEU*     3.1    30.3    -      -       +      +
    567D  GLY      2.6     9.4    +      -       -      +
    569D  ARG*     1.3    78.4    -      -       -      +
    571D  VAL*     1.3    57.6    +      -       -      -
    573D  ALA*     3.3     8.9    +      -       -      +
    574D  ALA*     2.9    27.5    +      -       -      +
    604D  MET*     3.9    22.0    -      -       +      +
    607D  ALA*     6.2     0.6    -      -       -      +
    611D  ARG*     4.3    16.6    +      -       -      +
    623D  PHE      4.4     1.9    -      -       -      +
   4999D  DEX      3.0    42.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 571 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    567D  GLY      2.9    13.1    +      -       -      +
    568D  GLY      3.7     8.7    -      -       -      +
    569D  ARG      3.3     0.4    -      -       -      -
    570D  GLN*     1.3    70.9    -      -       -      +
    572D  ILE*     1.3    55.9    +      -       -      +
    574D  ALA*     2.7    30.1    +      -       +      +
    575D  VAL*     2.7    28.0    +      -       +      +
    600D  TRP*     4.1    25.6    -      -       +      -
    604D  MET*     4.9     5.6    -      -       -      -
    752D  MET*     4.3    12.8    -      -       +      -
    753D  LEU*     3.5    31.9    -      -       +      -
    756D  ILE*     4.3    17.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 572 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    631A  GLU*     6.4     3.1    -      -       +      -
    632A  GLN*     5.6     7.0    -      -       +      -
    635A  THR*     3.8    33.7    -      -       +      +
    568D  GLY      3.3    19.1    -      -       -      +
    569D  ARG*     3.5    18.2    -      -       +      +
    571D  VAL*     1.3    76.9    -      -       -      +
    573D  ALA*     1.3    63.2    +      -       -      +
    575D  VAL*     3.1    20.4    +      -       +      +
    576D  LYS*     3.2    13.9    +      -       +      +
    752D  MET*     3.9    18.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 573 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    541D  PRO*     4.3    22.7    -      -       +      +
    542D  GLU      6.0     0.2    -      -       -      +
    544D  LEU*     5.3    11.0    -      -       +      -
    569D  ARG      3.2    11.3    +      -       -      +
    570D  GLN*     3.5    12.3    -      -       -      +
    571D  VAL      3.2     0.4    -      -       -      -
    572D  ILE*     1.3    80.5    -      -       -      +
    574D  ALA*     1.3    56.9    +      -       -      +
    576D  LYS*     3.6     8.6    +      -       -      +
    577D  TRP*     2.8    29.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 574 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    541D  PRO*     5.6     1.8    -      -       -      +
    570D  GLN      2.9    13.1    +      -       -      +
    571D  VAL*     2.7    23.9    +      -       +      +
    573D  ALA*     1.3    68.4    -      -       -      +
    575D  VAL*     1.3    68.8    +      -       +      +
    577D  TRP*     3.0    19.5    +      -       +      +
    578D  ALA*     2.7    20.7    +      -       -      +
    596D  LEU*     5.1     5.4    -      -       +      -
    603D  LEU*     5.5     9.6    -      -       +      -
    604D  MET*     4.8    12.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 575 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    571D  VAL*     2.7    31.7    +      -       +      +
    572D  ILE*     3.3    13.0    -      -       +      +
    574D  ALA*     1.3    70.6    -      -       -      +
    576D  LYS*     1.3    57.3    +      -       -      +
    578D  ALA*     2.5    32.8    +      -       -      +
    579D  LYS*     3.0    21.5    +      -       +      +
    596D  LEU*     4.5    25.1    -      -       +      -
    752D  MET*     6.1     2.2    -      -       -      -
    944H  LEU*     5.6     4.9    -      -       +      +
    947H  LEU*     4.1    37.2    -      -       +      +
    948H  LEU*     4.7     3.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 576 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    538C  VAL      5.3     6.1    +      -       -      -
    540C  GLU      5.6     3.6    +      -       -      -
    542C  GLU*     3.4    43.4    -      -       -      +
    572D  ILE*     3.2     7.8    +      -       +      +
    573D  ALA*     3.7    10.3    -      -       -      +
    575D  VAL*     1.3    81.6    -      -       -      +
    577D  TRP*     1.3    62.3    -      -       -      +
    579D  LYS*     3.3    14.1    +      -       +      +
    580D  ALA*     3.1    25.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with TRP 577 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    536D  LEU*     4.3     0.8    +      -       +      +
    539D  ILE*     3.0    54.0    -      -       +      +
    540D  GLU*     3.5    12.0    +      -       -      -
    541D  PRO*     3.3    17.9    -      -       +      -
    573D  ALA      2.8    16.6    +      -       -      +
    574D  ALA*     3.0    25.8    -      -       +      +
    575D  VAL      2.8     3.2    +      -       -      -
    576D  LYS*     1.3    74.3    -      -       -      +
    578D  ALA*     1.3    73.1    +      -       +      +
    580D  ALA*     3.1    20.2    +      -       -      +
    581D  ILE*     3.3    25.2    -      -       +      +
    596D  LEU*     6.1     1.1    -      -       +      -
    603D  LEU*     4.0    20.2    -      -       +      -
    667D  LYS*     2.6    55.7    -      -       +      +
    668D  THR*     4.1    13.7    -      -       -      -
    671D  LEU*     4.2    10.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 578 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    574D  ALA      2.7    10.4    +      -       -      +
    575D  VAL*     2.5    14.8    +      -       -      +
    577D  TRP*     1.3    73.6    -      -       +      +
    579D  LYS*     1.3    53.1    +      -       -      +
    581D  ILE*     2.5    52.6    +      -       +      +
    584D  PHE*     3.6    22.7    -      -       +      +
    596D  LEU*     3.6    26.2    -      -       +      -
    671D  LEU*     4.3     4.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 579 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    575D  VAL*     3.0    22.1    +      -       +      +
    576D  LYS*     3.6    14.4    -      -       +      +
    578D  ALA*     1.3    77.4    -      -       -      +
    580D  ALA*     1.3    58.8    +      -       -      +
    581D  ILE      3.1     1.1    -      -       -      +
    584D  PHE*     3.8    19.9    -      -       +      -
    585D  ARG*     2.7    58.4    -      -       +      +
    592D  GLN*     5.5     1.8    -      -       -      +
    596D  LEU*     6.2     0.2    -      -       +      -
    947H  LEU      3.4    20.1    +      -       -      +
    948H  LEU*     2.8    25.9    +      -       +      +
    950H  LYS      2.7    31.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 580 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    538C  VAL*     4.8    22.9    -      -       +      +
    535D  LEU*     5.2     3.5    -      -       -      +
    539D  ILE*     3.8    31.1    -      -       +      +
    576D  LYS*     3.1    16.3    +      -       -      +
    577D  TRP*     3.1    15.2    +      -       -      +
    578D  ALA      2.8     0.8    +      -       -      -
    579D  LYS*     1.3    76.6    -      -       -      +
    581D  ILE*     1.3    60.7    +      -       -      +
    582D  PRO*     3.7     7.3    -      -       -      +
----------------------------------------------------------
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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