Contacts of the helix formed by residues 555 - 579 (chain K) in PDB entry 4P6X


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 K).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    548K  TYR*     4.4     1.2    +      -       -      -
    553K  PRO      3.9     1.7    +      -       -      -
    554K  ASP*     1.3    76.8    -      -       -      +
    556K  THR*     1.3    65.1    +      -       -      +
    557K  TRP*     3.6    10.3    +      -       -      +
    558K  ARG*     3.0    28.4    +      -       -      +
    559K  ILE*     3.1    24.2    +      -       -      +
    636K  LEU*     4.5     8.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with THR 556 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    555K  SER*     1.3    71.4    -      -       -      +
    557K  TRP*     1.3    57.8    +      -       -      +
    559K  ILE*     3.7     0.3    -      -       -      +
    560K  MET*     3.0    62.3    +      -       +      +
    636K  LEU*     3.4    13.8    -      -       -      +
    637K  PRO*     3.3    36.8    -      -       +      +
    638K  CYS*     4.3    14.8    -      -       +      +
    639K  MET*     4.4    13.2    -      -       +      +
    745K  MET*     5.0    13.5    -      -       -      -
----------------------------------------------------------
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Residues in contact with TRP 557 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    555K  SER*     3.1     8.1    -      -       -      +
    556K  THR*     1.3    80.7    -      -       -      +
    558K  ARG*     1.3    94.7    +      -       +      +
    560K  MET*     4.2     0.5    -      -       -      +
    561K  THR*     2.9    56.9    +      -       +      -
    745K  MET*     3.0    38.3    +      -       +      -
    746K  SER*     2.7    23.0    +      -       -      -
    747K  ILE*     3.7    19.2    -      -       +      +
    748K  GLU*     3.6    26.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 558 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    548K  TYR*     2.9    44.8    +      -       +      -
    549K  ASP*     2.7    29.3    +      -       -      +
    552K  VAL*     3.0    46.6    +      -       -      +
    553K  PRO      3.0    16.0    +      -       -      -
    554K  ASP*     3.6     1.0    +      -       -      +
    555K  SER*     3.0    20.9    +      -       -      +
    557K  TRP*     1.3    97.4    -      -       +      +
    559K  ILE*     1.3    55.8    +      -       -      +
    561K  THR*     3.9     2.0    -      -       -      +
    562K  THR*     2.7    42.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 559 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    548K  TYR*     3.6    29.8    -      -       +      +
    554K  ASP*     4.3     6.1    -      -       +      -
    555K  SER      3.1    14.2    +      -       -      +
    556K  THR      3.7     2.7    -      -       -      +
    558K  ARG*     1.3    76.6    -      -       -      +
    560K  MET*     1.3    58.9    +      -       -      +
    562K  THR*     3.1     5.4    +      -       -      -
    563K  LEU*     2.9    43.5    +      -       +      +
    627K  LEU*     4.5     8.7    -      -       +      +
    629K  ILE*     3.9    17.0    -      -       +      -
    633K  ARG*     4.3    19.3    -      -       +      +
    636K  LEU*     3.8    19.7    -      -       +      -
    639K  MET*     3.6    29.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with MET 560 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    556K  THR*     3.0    41.4    +      -       +      +
    557K  TRP      4.2     0.2    -      -       -      +
    559K  ILE*     1.3    77.0    -      -       -      +
    561K  THR*     1.3    61.7    +      -       -      +
    563K  LEU*     3.3    13.1    +      -       +      +
    564K  ASN*     3.1    28.4    +      -       -      -
    638K  CYS*     4.0    17.0    -      -       +      +
    639K  MET*     4.1    20.2    -      -       -      -
    642K  GLN*     3.2    41.5    -      -       +      +
    739K  THR*     4.7     0.2    -      -       -      -
    747K  ILE*     3.6    36.3    -      -       +      -
    900K  HCY      3.9    15.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 561 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    557K  TRP*     2.9    49.0    +      -       +      -
    558K  ARG*     3.9     4.7    -      -       -      +
    560K  MET*     1.3    75.6    -      -       -      +
    562K  THR*     1.3    64.9    +      -       -      +
    564K  ASN*     3.3     4.2    +      -       -      +
    565K  MET*     3.2    29.0    +      -       +      +
    747K  ILE*     3.3    10.6    -      -       -      +
    748K  GLU*     3.0    44.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with THR 562 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    546K  ALA*     3.7    26.4    -      -       +      +
    547K  GLY      5.1     0.4    -      -       -      -
    548K  TYR*     3.6    23.3    -      -       +      -
    558K  ARG*     2.7    27.1    +      -       -      +
    559K  ILE      3.4     4.3    -      -       -      -
    561K  THR*     1.3    76.5    -      -       -      +
    563K  LEU*     1.3    58.4    +      -       -      +
    565K  MET*     3.3    10.4    +      -       +      +
    566K  LEU*     2.9    26.2    +      -       -      +
    627K  LEU*     3.7    21.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 563 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    559K  ILE*     2.9    32.4    +      -       +      +
    560K  MET*     3.5    15.3    -      -       +      +
    561K  THR      3.2     0.2    -      -       -      -
    562K  THR*     1.3    76.8    -      -       -      +
    564K  ASN*     1.3    51.2    +      -       -      +
    566K  LEU*     3.2    10.3    +      -       +      +
    567K  GLY      2.7    30.8    +      -       -      -
    623K  PHE*     3.5    55.0    -      -       +      -
    627K  LEU*     3.5    28.0    -      -       +      -
    629K  ILE*     5.1     0.2    -      -       +      -
    639K  MET*     5.6     3.8    -      -       -      -
    646K  MET*     6.1     0.2    -      -       +      -
    900K  HCY      3.3    34.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 564 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    560K  MET      3.1    20.4    +      -       -      -
    561K  THR      3.7     2.0    -      -       -      +
    562K  THR      3.3     0.2    -      -       -      -
    563K  LEU*     1.3    74.3    -      -       -      +
    565K  MET*     1.3    60.6    +      -       -      +
    567K  GLY      3.2     0.2    +      -       -      -
    568K  GLY      2.9    24.3    +      -       -      -
    747K  ILE*     3.4    18.0    -      -       -      +
    748K  GLU      3.3    17.8    +      -       -      +
    749K  PHE*     3.2    43.1    -      -       +      -
    750K  PRO*     3.4    13.3    -      -       +      +
    753K  LEU*     3.2    10.3    -      -       -      +
    900K  HCY      2.9    37.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with MET 565 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    546K  ALA      6.1     0.9    -      -       -      +
    561K  THR*     3.2    17.6    +      -       +      +
    562K  THR*     3.5    10.1    -      -       +      +
    563K  LEU      3.3     0.2    -      -       -      -
    564K  ASN*     1.3    76.1    -      -       -      +
    566K  LEU*     1.3    64.0    +      -       -      +
    568K  GLY*     3.3     9.9    +      -       -      -
    569K  ARG*     3.3    19.4    +      -       -      +
    748K  GLU*     3.3    38.1    -      -       +      +
    749K  PHE      3.4     4.9    -      -       -      +
    750K  PRO*     3.4    40.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 566 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    544K  LEU*     3.9    19.1    -      -       +      -
    545K  TYR      4.0     9.0    -      -       -      +
    546K  ALA*     4.3    13.7    +      -       +      +
    562K  THR      2.9    13.9    +      -       -      +
    563K  LEU*     3.3    11.9    -      -       +      +
    565K  MET*     1.3    76.5    -      -       -      +
    567K  GLY*     1.3    56.9    +      -       -      +
    569K  ARG*     3.0    32.3    +      -       -      +
    570K  GLN*     2.8    58.1    +      -       +      +
    623K  PHE*     3.7    24.0    -      -       +      +
    624K  ALA*     4.1    10.8    -      -       +      -
    900K  HCY      4.1     9.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 567 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    563K  LEU      2.7    18.1    +      -       -      -
    564K  ASN      3.2     4.2    +      -       -      -
    566K  LEU*     1.3    73.1    -      -       -      +
    568K  GLY*     1.3    57.2    +      -       -      +
    570K  GLN*     3.6     4.4    -      -       -      +
    571K  VAL*     2.8    36.2    +      -       -      +
    753K  LEU*     3.9     7.2    -      -       -      -
    900K  HCY      3.9    29.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLY 568 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    564K  ASN      2.9    14.0    +      -       -      -
    565K  MET      3.3     4.5    +      -       -      -
    566K  LEU      3.2     0.4    -      -       -      -
    567K  GLY*     1.3    76.0    -      -       -      +
    569K  ARG*     1.3    61.6    +      -       -      +
    571K  VAL*     3.5     3.5    +      -       -      +
    572K  ILE*     3.2    31.5    +      -       -      +
    750K  PRO*     3.9    17.0    -      -       -      -
    752K  MET*     4.5     8.3    -      -       -      +
    753K  LEU*     3.6    10.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 569 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    544K  LEU*     3.7    37.4    -      -       +      +
    545K  TYR      2.4    33.1    +      -       -      +
    546K  ALA*     4.5     4.4    +      -       -      +
    565K  MET      3.3    13.2    +      -       -      +
    566K  LEU*     3.0    21.6    +      -       -      +
    568K  GLY*     1.3    74.2    -      -       -      +
    570K  GLN*     1.3    60.4    +      -       -      +
    572K  ILE*     3.4    14.9    +      -       +      +
    573K  ALA*     3.0    26.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 570 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    543K  VAL*     6.3     0.6    -      -       -      +
    544K  LEU*     4.3    15.1    +      -       +      +
    566K  LEU*     2.8    46.0    +      -       +      +
    567K  GLY      3.6     7.6    -      -       -      +
    569K  ARG*     1.3    75.2    -      -       -      +
    571K  VAL*     1.3    52.9    +      -       -      +
    573K  ALA*     3.1     8.3    +      -       -      +
    574K  ALA*     2.7    34.1    +      -       -      +
    604K  MET*     3.3    30.0    -      -       +      +
    607K  ALA*     5.8     0.5    -      -       -      +
    611K  ARG*     4.2    11.3    +      -       -      +
    623K  PHE      4.0     6.5    +      -       -      -
    900K  HCY      3.1    39.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 571 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    567K  GLY      2.8    20.3    +      -       -      +
    568K  GLY*     3.8     4.9    -      -       -      +
    570K  GLN*     1.3    72.5    -      -       -      +
    572K  ILE*     1.3    62.4    +      -       -      +
    574K  ALA*     2.9    23.0    +      -       +      +
    575K  VAL*     3.0    21.9    +      -       +      +
    596K  LEU*     6.2     2.5    -      -       +      -
    600K  TRP*     3.8    27.8    -      -       +      -
    604K  MET*     4.0     9.4    -      -       -      -
    752K  MET*     4.6    13.9    -      -       +      -
    753K  LEU*     3.8    21.3    -      -       +      -
    756K  ILE*     4.0    24.0    -      -       +      -
    745L  LEU*     5.9     0.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 572 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    568K  GLY      3.2    19.2    +      -       -      +
    569K  ARG*     3.5    15.7    -      -       +      +
    571K  VAL*     1.3    76.2    -      -       -      +
    573K  ALA*     1.3    61.9    +      -       -      +
    575K  VAL*     3.5    11.4    +      -       -      +
    576K  LYS*     3.5    13.8    +      -       +      +
    752K  MET*     3.4    38.1    -      -       +      -
    744L  LEU*     5.4     4.3    -      -       +      -
    748L  LEU*     4.4    16.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 573 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    541K  PRO*     4.4    15.9    -      -       +      +
    544K  LEU*     5.1     9.4    -      -       +      -
    569K  ARG      3.0    15.3    +      -       -      +
    570K  GLN*     3.1    10.7    +      -       -      +
    572K  ILE*     1.3    75.4    -      -       -      +
    574K  ALA*     1.3    65.1    +      -       -      +
    575K  VAL      3.3     0.2    -      -       -      -
    576K  LYS*     3.0    42.8    -      -       -      +
    577K  TRP*     3.1     6.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 574 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    541K  PRO*     5.6     1.8    -      -       -      -
    570K  GLN      2.7    16.5    +      -       -      +
    571K  VAL*     2.9    16.1    +      -       +      +
    573K  ALA*     1.3    76.6    -      -       -      +
    575K  VAL*     1.3    58.0    +      -       -      +
    577K  TRP*     3.2    17.8    -      -       +      +
    578K  ALA*     2.8    27.0    +      -       -      +
    596K  LEU*     4.3     5.9    -      -       +      +
    603K  LEU*     4.6    18.4    -      -       +      -
    604K  MET*     4.4    15.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 575 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    571K  VAL*     3.0    27.2    +      -       +      +
    572K  ILE*     3.8     7.4    -      -       -      +
    573K  ALA      3.3     0.2    -      -       -      -
    574K  ALA*     1.3    73.9    -      -       -      +
    576K  LYS*     1.3    66.7    +      -       -      +
    577K  TRP      3.1     1.1    -      -       -      -
    578K  ALA*     3.4     2.4    +      -       -      +
    579K  LYS*     3.2    23.3    +      -       -      +
    596K  LEU*     3.8    18.6    -      -       +      -
    752K  MET*     5.0     4.3    -      -       +      -
    745L  LEU*     3.4    24.0    -      -       +      -
    748L  LEU*     4.0    27.4    -      -       +      +
    749L  LEU*     3.6    30.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 576 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    539K  ILE      3.5    19.0    +      -       -      -
    541K  PRO*     3.1    36.9    -      -       -      +
    572K  ILE*     3.5     6.3    +      -       +      +
    573K  ALA*     3.0    32.3    +      -       -      +
    575K  VAL*     1.3    79.4    -      -       -      +
    577K  TRP*     1.3    62.9    +      -       -      +
    579K  LYS*     3.3    22.4    -      -       +      +
    580K  ALA*     3.7     9.7    +      -       -      +
    748L  LEU      6.0     0.2    -      -       -      -
    753L  ASP*     5.0     8.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with TRP 577 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    536K  LEU*     5.0     4.6    +      -       -      +
    539K  ILE*     3.5    41.0    -      -       +      +
    540K  GLU*     3.7     4.2    +      -       -      -
    541K  PRO*     3.9    14.4    -      -       +      -
    573K  ALA      3.1    11.6    +      -       -      +
    574K  ALA*     3.2    28.5    -      -       +      +
    576K  LYS*     1.3    90.4    -      -       -      +
    578K  ALA*     1.3    71.7    +      -       +      +
    580K  ALA*     3.0    17.9    +      -       -      +
    581K  ILE*     3.4    35.0    +      -       +      +
    603K  LEU*     3.7    38.1    -      -       +      -
    664K  LEU      5.4     0.2    -      -       -      -
    667K  LYS*     3.3    37.3    -      -       +      +
    668K  VAL*     4.1    16.8    -      -       +      -
    671K  LEU*     4.0    10.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 578 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    574K  ALA      2.8    19.1    +      -       -      +
    575K  VAL      3.4     5.1    +      -       -      +
    577K  TRP*     1.3    79.5    -      -       +      +
    579K  LYS*     1.3    57.9    +      -       -      +
    581K  ILE*     2.9    34.9    +      -       -      +
    584K  PHE*     3.0    39.3    -      -       +      +
    596K  LEU*     4.1    15.9    -      -       +      -
    671K  LEU*     4.1     6.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 579 (chain K). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    575K  VAL*     3.2    12.7    +      -       -      +
    576K  LYS*     3.3    20.4    -      -       -      +
    578K  ALA*     1.3    78.4    -      -       -      +
    580K  ALA*     1.3    58.4    +      -       +      +
    581K  ILE      3.2     3.9    +      -       -      +
    584K  PHE*     3.8    11.0    -      -       +      -
    585K  ARG*     3.2    49.4    +      -       +      +
    592K  GLN*     5.3     0.2    -      -       -      +
    748L  LEU      2.7    27.3    +      -       -      -
    749L  LEU*     2.9    32.7    +      -       +      +
    751L  LYS      3.5     5.3    +      -       -      -
    753L  ASP*     2.6    40.3    +      -       -      +
----------------------------------------------------------
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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