Contacts of the helix formed by residues 30 - 55 (chain C) in PDB entry 3EXG


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 GLU 30 (chain C).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      3C  ASN      4.3     1.5    +      -       -      +
     28C  THR*     2.5    12.6    +      -       -      +
     29C  ARG*     1.3    86.0    -      -       +      +
     31C  ASP*     1.3    69.6    +      -       -      +
     33C  LEU*     3.4    20.7    -      -       +      +
     34C  LYS*     3.7     5.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 31 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27C  LEU*     4.2     6.5    -      -       +      -
     28C  THR*     2.7    38.4    +      -       +      +
     30C  GLU*     1.3    73.9    +      -       -      +
     32C  GLY*     1.3    54.0    +      -       -      +
     33C  LEU      2.9     4.5    -      -       -      -
     34C  LYS*     2.6    54.0    +      -       -      +
     35C  TYR*     3.0    30.8    +      -       +      -
    234C  ARG*     4.9     2.8    +      -       -      +
    238C  ARG*     5.9     0.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLY 32 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27C  LEU*     3.3    29.8    -      -       -      +
     28C  THR      3.1     8.3    +      -       -      -
     29C  ARG      4.0     0.4    -      -       -      -
     31C  ASP*     1.3    75.2    -      -       -      +
     33C  LEU*     1.3    56.6    +      -       -      +
     34C  LYS      3.3     0.4    -      -       -      -
     35C  TYR*     3.7    14.1    -      -       -      -
     36C  TYR*     3.3    18.0    +      -       -      +
    291C  LEU*     3.9     4.1    -      -       -      +
    295C  MET*     2.9    22.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 33 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     29C  ARG*     3.2    35.9    +      -       -      +
     30C  GLU*     3.4    16.4    -      -       +      +
     31C  ASP      2.8     1.0    +      -       -      -
     32C  GLY*     1.3    78.0    -      -       -      +
     34C  LYS*     1.3    58.5    +      -       -      +
     36C  TYR*     3.8     3.3    -      -       -      +
     37C  ARG*     3.3    25.5    +      -       -      +
    295C  MET*     3.5    20.2    -      -       +      -
    300C  LEU      5.1     0.7    -      -       -      +
    301C  ALA*     3.9    17.5    -      -       +      -
    305C  GLU*     5.0     7.2    -      -       +      +
    306C  LEU*     4.3    12.8    -      -       +      -
    309C  ILE*     4.6    12.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 34 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30C  GLU      4.4     4.3    -      -       -      +
     31C  ASP*     2.6    29.3    +      -       -      +
     33C  LEU*     1.3    79.5    -      -       -      +
     35C  TYR*     1.3    69.2    +      -       -      -
     36C  TYR      3.2     0.2    -      -       -      -
     37C  ARG*     4.0    10.6    -      -       -      +
     38C  MET*     3.1    60.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 35 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27C  LEU*     4.0    11.2    -      -       +      -
     31C  ASP*     3.0    26.5    +      -       +      -
     32C  GLY*     3.7    19.5    -      -       -      +
     34C  LYS*     1.3    93.2    -      -       -      +
     36C  TYR*     1.3    65.8    +      -       -      +
     38C  MET*     4.0    12.7    -      -       +      +
     39C  MET*     3.0    29.5    +      -       -      +
     73C  VAL*     4.2    11.8    -      -       +      +
     77C  ALA*     3.4    34.2    +      -       +      +
    230C  ILE*     3.9    27.4    -      -       +      -
    231C  LEU*     5.1     3.6    -      -       +      -
    234C  ARG*     3.3    36.0    +      -       -      -
    238C  ARG*     4.7     1.7    +      -       -      -
    291C  LEU*     4.2     9.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 36 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     32C  GLY      3.3    16.6    +      -       -      +
     33C  LEU*     3.8     6.1    -      -       -      +
     34C  LYS      3.2     0.6    -      -       -      -
     35C  TYR*     1.3    82.1    -      -       -      +
     37C  ARG*     1.3    69.2    +      -       -      +
     39C  MET*     3.0     4.0    +      -       +      +
     40C  GLN*     2.8    41.0    +      -       +      +
    288C  ILE*     3.5    29.6    -      -       +      +
    291C  LEU*     3.6    22.3    -      -       +      +
    292C  LYS*     4.1    15.9    -      -       +      +
    295C  MET*     5.0     1.3    -      -       +      -
    306C  LEU*     4.0    42.5    -      -       +      +
    309C  ILE*     3.7    22.2    -      -       +      -
    310C  ASP*     2.8    34.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 37 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     33C  LEU      3.3    15.7    +      -       -      +
     34C  LYS*     3.5    10.7    +      -       -      +
     36C  TYR*     1.3    82.7    -      -       -      +
     38C  MET*     1.3    57.2    +      -       +      +
     40C  GLN*     3.4     4.4    +      -       -      +
     41C  THR*     2.7    42.1    +      -       -      +
    309C  ILE*     2.9    39.0    -      -       +      +
    312C  GLU*     3.1    32.9    +      -       -      +
    313C  VAL*     4.1    13.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with MET 38 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     34C  LYS*     3.1    65.6    +      -       +      +
     35C  TYR*     4.0     5.4    -      -       +      -
     36C  TYR      3.0     0.4    +      -       -      -
     37C  ARG*     1.3    73.8    -      -       +      +
     39C  MET*     1.3    69.5    +      -       -      +
     40C  GLN      2.8     2.5    +      -       -      -
     41C  THR*     2.8    16.5    +      -       -      -
     42C  VAL*     3.0    14.2    +      -       -      +
     73C  VAL*     3.9    31.6    -      -       +      -
     76C  GLU*     5.8     8.1    -      -       +      -
     96C  PHE*     4.3    18.4    -      -       +      -
     97C  THR*     4.9    17.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with MET 39 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     35C  TYR      3.0    12.7    +      -       -      +
     36C  TYR*     3.0     5.4    +      -       -      +
     38C  MET*     1.3    75.1    -      -       -      +
     40C  GLN*     1.3    62.3    +      -       -      +
     42C  VAL*     3.2     5.3    +      -       -      +
     43C  ARG*     3.0    18.7    +      -       -      +
     69C  GLU*     3.7    27.7    -      -       +      +
     70C  ALA*     4.1    10.8    -      -       -      -
     73C  VAL*     3.6    25.2    -      -       +      +
    230C  ILE*     4.7    12.8    -      -       +      -
    287C  PRO*     3.5    27.4    -      -       -      +
    288C  ILE*     3.6    34.0    -      -       +      +
    291C  LEU*     3.6    31.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLN 40 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     36C  TYR*     2.8    54.2    +      -       +      +
     37C  ARG*     3.6     6.1    -      -       -      +
     38C  MET      2.8     1.6    +      -       -      -
     39C  MET*     1.3    71.4    -      -       -      +
     41C  THR*     1.3    63.7    +      -       -      +
     43C  ARG*     3.0    18.8    +      -       -      +
     44C  ARG*     3.0    53.1    +      -       -      +
    288C  ILE*     3.8    24.0    -      -       +      +
    309C  ILE      6.0     0.7    -      -       -      +
    310C  ASP*     3.5    25.7    -      -       -      +
    313C  VAL*     4.3     9.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with THR 41 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     37C  ARG*     2.7    25.9    +      -       -      +
     38C  MET*     2.8     8.8    +      -       -      -
     40C  GLN*     1.3    76.9    -      -       -      +
     42C  VAL*     1.3    62.9    +      -       -      +
     43C  ARG      3.3     0.2    +      -       -      -
     44C  ARG*     3.4     2.1    +      -       -      +
     45C  MET*     3.1    21.2    +      -       +      +
     96C  PHE*     3.5    33.1    -      -       +      -
    102C  VAL*     3.7    24.2    -      -       +      -
    313C  VAL*     3.3    25.4    -      -       +      +
    316C  GLU*     6.0     3.5    -      -       +      +
    317C  ILE*     4.1     6.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 42 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     38C  MET      3.0    13.5    +      -       -      +
     39C  MET*     3.7     7.9    -      -       -      +
     41C  THR*     1.3    75.1    -      -       -      +
     43C  ARG*     1.3    63.6    +      -       -      +
     45C  MET*     3.2     9.3    +      -       -      +
     46C  GLU*     3.0    25.5    +      -       +      +
     65C  CYS*     3.7    29.6    -      -       -      -
     69C  GLU*     3.7    17.9    -      -       +      -
     72C  CYS*     4.5     6.5    -      -       -      -
     73C  VAL*     5.1     0.9    -      -       +      -
     93C  GLY*     3.9    23.1    -      -       -      +
     96C  PHE*     3.7    26.7    -      -       +      -
     97C  THR*     4.4     8.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 43 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39C  MET      3.0    11.4    +      -       -      +
     40C  GLN*     3.0    21.5    +      -       -      +
     42C  VAL*     1.3    77.7    -      -       -      +
     44C  ARG*     1.3    69.9    +      -       -      +
     45C  MET      3.1     0.2    -      -       -      -
     46C  GLU*     3.4     3.8    +      -       -      +
     47C  LEU*     2.9    40.7    +      -       -      +
     66C  ASP*     3.6    14.7    +      -       -      +
     67C  GLY      3.9     0.2    -      -       -      +
     69C  GLU*     2.6    47.2    +      -       -      +
    260C  TYR*     3.6    16.4    -      -       -      -
    282C  ARG*     4.6     8.4    -      -       -      +
    286C  ASP*     2.8    37.9    +      -       -      -
    287C  PRO*     4.1     3.8    -      -       -      +
    288C  ILE*     3.8    14.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 44 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     40C  GLN*     3.0    40.8    +      -       -      +
     41C  THR      4.1     0.7    -      -       -      +
     43C  ARG*     1.3    80.1    -      -       -      +
     45C  MET*     1.3    62.8    +      -       -      +
     47C  LEU*     3.5    33.7    -      -       -      +
     48C  LYS*     3.2    21.5    +      -       -      +
    310C  ASP      6.1     0.2    -      -       -      +
    313C  VAL*     3.5    17.9    -      -       +      -
    314C  ARG*     3.3    47.8    -      -       -      +
    317C  ILE*     3.5    26.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with MET 45 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     41C  THR*     3.1    17.1    +      -       +      +
     42C  VAL*     3.6    10.1    -      -       -      +
     43C  ARG      3.1     0.2    -      -       -      -
     44C  ARG*     1.3    77.7    -      -       -      +
     46C  GLU*     1.3    66.2    +      -       -      +
     48C  LYS*     2.9     7.4    +      -       -      +
     49C  ALA*     2.8    33.5    +      -       +      +
     92C  HIS*     4.7    11.4    -      -       -      +
     96C  PHE*     4.5     7.4    -      -       +      -
    102C  VAL*     3.4    51.8    -      -       +      +
    105C  ILE*     3.5    38.4    -      -       +      -
    106C  LEU*     4.4    13.6    -      -       +      +
    317C  ILE*     3.8    11.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 46 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     42C  VAL*     3.0    19.9    +      -       +      +
     43C  ARG      3.7     4.7    -      -       -      +
     45C  MET*     1.3    85.3    -      -       +      +
     47C  LEU*     1.3    57.3    +      -       -      +
     49C  ALA*     3.7     6.0    -      -       -      +
     50C  ASP*     3.1    27.2    +      -       -      +
     63C  HIS      3.5     0.9    -      -       -      +
     64C  LEU*     3.1    26.7    -      -       +      +
     65C  CYS*     2.7    46.9    +      -       -      +
     66C  ASP*     4.4    16.8    -      -       +      +
     92C  HIS*     2.9    39.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 47 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     43C  ARG*     2.9    31.5    +      -       -      +
     44C  ARG*     3.5    36.6    -      -       -      +
     45C  MET      3.2     0.2    -      -       -      -
     46C  GLU*     1.3    76.6    -      -       -      +
     48C  LYS*     1.3    62.7    +      -       -      +
     50C  ASP*     3.5     9.0    +      -       +      +
     51C  GLN*     3.3    22.0    +      -       -      +
     66C  ASP*     4.2    11.7    -      -       -      +
    261C  HIS*     4.1    26.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 48 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     44C  ARG      3.2    16.0    +      -       -      +
     45C  MET*     2.9    10.4    +      -       -      +
     47C  LEU*     1.3    72.6    -      -       -      +
     49C  ALA*     1.3    66.9    +      -       -      +
     51C  GLN*     3.1    34.5    +      -       -      +
     52C  LEU*     2.9    30.7    +      -       +      +
    106C  LEU*     3.8    24.0    -      -       +      -
    317C  ILE*     3.7    21.8    -      -       +      -
    318C  GLU*     3.9    20.5    +      -       -      -
    321C  ALA*     3.6    21.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 49 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     45C  MET*     2.8    14.6    +      -       +      +
     46C  GLU*     3.7    10.5    -      -       -      +
     48C  LYS*     1.3    76.5    -      -       -      +
     50C  ASP*     1.3    58.6    +      -       -      +
     52C  LEU*     2.8    20.7    +      -       -      +
     53C  TYR*     2.8    16.4    +      -       -      +
     58C  ILE*     3.5    10.2    -      -       +      +
     62C  CYS*     4.5     2.2    -      -       -      -
     64C  LEU*     4.2    14.4    -      -       +      -
    106C  LEU*     4.4     7.8    -      -       +      +
    109C  LEU*     4.1    24.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASP 50 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     46C  GLU      3.1    14.9    +      -       -      +
     47C  LEU*     3.7    12.9    -      -       -      +
     48C  LYS      3.3     0.2    -      -       -      -
     49C  ALA*     1.3    80.4    -      -       -      +
     51C  GLN*     1.3    60.1    +      -       -      +
     53C  TYR*     3.5    10.9    +      -       -      +
     54C  LYS*     3.0    50.4    +      -       -      +
     62C  CYS*     5.4     0.2    -      -       -      -
     64C  LEU*     3.5    18.8    -      -       +      +
    261C  HIS*     3.7    29.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 51 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     47C  LEU      3.3    10.8    +      -       -      +
     48C  LYS*     3.1    39.6    +      -       -      +
     49C  ALA      3.0     0.6    -      -       -      -
     50C  ASP*     1.3    83.5    -      -       -      +
     52C  LEU*     1.3    68.5    +      -       -      +
     54C  LYS*     3.6     6.1    +      -       +      +
     55C  GLN*     3.1    53.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 52 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     48C  LYS*     2.9    33.1    +      -       +      +
     49C  ALA      2.8     8.6    +      -       -      +
     51C  GLN*     1.3    88.3    -      -       -      +
     53C  TYR*     1.3    57.5    +      -       -      +
     55C  GLN*     3.5    19.0    -      -       -      +
     56C  LYS      3.2     4.7    +      -       -      -
     57C  ILE*     3.0    35.6    +      -       +      +
     58C  ILE*     3.5    14.7    +      -       +      -
    106C  LEU*     4.6    15.5    -      -       +      -
    110C  THR*     3.8    23.3    -      -       +      -
    321C  ALA*     4.8     9.9    -      -       +      -
    324C  ALA*     5.2     1.3    -      -       +      -
    325C  THR*     4.3    21.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 53 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     49C  ALA      2.8    14.9    +      -       -      +
     50C  ASP*     3.6    14.4    -      -       -      +
     52C  LEU*     1.3    75.2    -      -       -      +
     54C  LYS*     1.3    64.9    +      -       +      +
     55C  GLN      3.1     1.3    -      -       -      -
     56C  LYS*     2.8    27.8    +      -       -      +
     58C  ILE*     3.7    34.5    -      -       +      +
     59C  ARG*     4.7     1.1    -      -       -      -
     60C  GLY      3.1    26.6    +      -       -      -
     61C  PHE*     4.2     0.8    -      -       -      -
     62C  CYS*     3.1    39.6    +      -       +      -
     64C  LEU*     6.3     1.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 54 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     50C  ASP*     3.0    42.9    +      -       -      +
     51C  GLN*     4.0     7.0    -      -       -      +
     53C  TYR*     1.3    80.2    -      -       +      +
     55C  GLN*     1.3    61.6    +      -       +      +
     56C  LYS*     3.6    10.4    +      -       -      +
    261C  HIS*     5.6     3.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLN 55 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     51C  GLN*     3.1    51.8    +      -       +      +
     52C  LEU*     3.5    16.0    -      -       -      +
     54C  LYS*     1.3    79.3    -      -       -      +
     56C  LYS*     1.3    69.3    +      -       -      +
     57C  ILE*     3.5    30.7    +      -       +      +
----------------------------------------------------------
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A short description of the analytical approach
The contact analysis used in this page is based upon the approach developed in: Sobolev V., Wade R.C., Vriend G. and Edelman M. PROTEINS (1996) 25, 120-129. Contact legitimacy depends on the hydrophobic-hydrophilic properties of the contacting atoms. In order to define it, for each inter-atomic contact, eight atom classes have been introduced:


   I  Hydrophilic      - N and O that can donate and accept hydrogen bonds
                         (e.g., oxygen of hydroxyl group of Ser. or Thr)
  II  Acceptor         - N or O that can only accept a hydrogen bond
 III  Donor            - N that can only donate a hydrogen bond
  IV  Hydrophobic      - Cl, Br, I and all C atoms that are not in
                         aromatic rings and do not have a covalent bond to
                         a N or O atom
   V  Aromatic         - C in aromatic rings irrespective of any other 
                         bonds formed by the atom
  VI  Neutral          - C atoms that have a covalent bond to at least one
                         atom of class I or two or more atoms from class II
                         or III; atoms; S, F, P, and metal atoms in all cases
 VII  Neutral-donor    - C atoms that have a covalent bond with only one
                         atom of class III
VIII  Neutral-acceptor - C atoms that have a covalent bond with only 
                         one atom of class II
For each pair of contacts the state of legitimacy is shown below:

Legend:
+, legitimate
-, illegitimate
------------------------------------------------------------
  Atomic class           I  II  III   IV   V   VI  VII  VIII
------------------------------------------------------------
   I  (Hydrophilic)      +   +    +    -   +   +    +    +
  II  (Acceptor)         +   -    +    -   +   +    +    -
 III  (Donor)            +   +    -    -   +   +    -    +
  IV  (Hydrophobic)      -   -    -    +   +   +    +    +
   V  (Aromatic)         +   +    +    +   +   +    +    +
  VI  (Neutral)          +   +    +    +   +   +    +    +
 VII  (Neutral-donor)    +   +    -    +   +   +    -    +
VIII  (Neutral-acceptor) +   -    +    +   +   +    +    -
------------------------------------------------------------
Warning!
Atom classes for heterogroups are automatically assigned based on the atomic coordinates. However, in three cases (see below) the automatic assignment is currently ambiguous. In these cases, the user is advised to manually analyse the full list of contacts using LPC software.
1. Carbon atoms belonging to a 4-, 5- or 6-member ring are 
   considered "aromatic" (Class V) if the ring is approximately
   planar, and "hydrophobic" (Class IV) or "neutral" (Classes
   VI, VII, VIII) if the ring is non-planar.
2. The oxygen atom of a carbonyl or hydroxy group is considered
   "hydroxy" (Class I) if the CO bond is longer than 1.29 Å, and
   "carbonyl" (Class II) if shorter.
3. All nitrogen atoms are considered "hydrophilic" (Class I).

Please E-mail any questions and/or suggestions concerning this page to Vladimir.Sobolev@weizmann.ac.il