Contacts of the helix formed by residues 31 - 59 (chain A) in PDB entry 5SY1


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 CYS 31 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     29A  PRO*     3.8    14.4    -      -       -      -
     30A  PRO*     1.3    82.0    -      -       -      +
     32A  ASP*     1.3    60.1    +      -       -      +
     33A  PRO*     3.9     9.4    -      -       +      -
     34A  THR*     3.3    30.9    -      -       -      +
     35A  ALA*     3.0    27.6    +      -       -      +
    170A  ASP*     5.7     0.7    -      -       -      -
    171A  CYS*     3.6    31.9    -      -       -      -
----------------------------------------------------------
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Residues in contact with ASP 32 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30A  PRO      4.2     1.0    +      -       -      -
     31A  CYS*     1.3    70.5    -      -       -      +
     33A  PRO*     1.3    68.1    -      -       +      +
     35A  ALA*     4.1     8.9    -      -       -      +
     36A  ASP*     3.2    22.5    +      -       -      +
    166A  TRP*     4.7     9.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with PRO 33 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31A  CYS*     3.6    11.4    -      -       +      -
     32A  ASP*     1.3    91.7    -      -       +      +
     34A  THR*     1.3    52.7    +      -       -      +
     36A  ASP*     3.0     4.8    +      -       +      +
     37A  GLU*     2.4    37.0    +      -       -      +
     40A  PHE*     4.1     3.4    -      -       +      -
    166A  TRP*     3.6    37.0    -      -       +      -
    167A  GLN*     3.8    27.1    -      -       +      +
    170A  ASP*     3.6    31.9    -      -       -      +
    171A  CYS*     5.3     1.6    -      -       -      -
----------------------------------------------------------
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Residues in contact with THR 34 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31A  CYS*     3.2    28.8    +      -       -      +
     33A  PRO*     1.3    73.9    -      -       -      +
     35A  ALA*     1.3    61.4    +      -       -      +
     37A  GLU*     3.0    28.2    +      -       +      +
     38A  GLY      3.5     5.9    +      -       -      -
    167A  GLN*     5.4     1.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 35 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31A  CYS      3.0    16.8    +      -       -      +
     32A  ASP*     4.2    11.0    -      -       -      +
     34A  THR*     1.3    76.2    -      -       -      +
     36A  ASP*     1.3    58.1    +      -       -      +
     38A  GLY*     4.4     4.2    +      -       -      -
     39A  LEU*     4.6     4.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 36 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     32A  ASP      3.2    17.5    +      -       -      +
     33A  PRO*     3.0     2.7    +      -       +      +
     35A  ALA*     1.3    73.5    -      -       -      +
     37A  GLU*     1.3    53.1    +      -       -      +
     38A  GLY      3.2     2.2    -      -       -      -
     39A  LEU*     2.9    31.2    +      -       -      +
     40A  PHE*     2.4    70.1    +      -       +      -
    166A  TRP*     5.4     2.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 37 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     33A  PRO      2.4    25.1    +      -       -      +
     34A  THR*     3.0    19.0    +      -       +      +
     36A  ASP*     1.3    70.8    -      -       -      +
     38A  GLY*     1.3    50.4    +      -       -      +
     40A  PHE*     3.7    17.1    -      -       -      +
     41A  HIS*     2.5    72.9    +      -       +      -
    163A  ILE*     4.4     2.6    -      -       -      +
    167A  GLN*     2.4    33.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 38 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     34A  THR      3.5     7.5    +      -       -      -
     35A  ALA      4.4     3.1    +      -       -      -
     36A  ASP*     3.2     1.0    -      -       -      +
     37A  GLU*     1.3    79.5    -      -       -      +
     39A  LEU*     1.3    56.2    +      -       -      +
     41A  HIS*     3.7    11.2    -      -       -      +
     42A  ILE*     3.3    27.5    +      -       -      +
    113A  PHE*     4.8    13.1    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 39 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     35A  ALA      4.6     2.7    +      -       -      +
     36A  ASP*     2.9    29.8    +      -       -      +
     38A  GLY*     1.3    75.3    -      -       -      +
     40A  PHE*     1.3    52.8    +      -       -      +
     41A  HIS      3.2     1.1    -      -       -      -
     42A  ILE*     3.0    27.0    +      -       +      +
     43A  CYS*     2.6    41.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 40 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     33A  PRO*     4.1     3.8    -      -       +      -
     36A  ASP*     2.4    70.1    +      -       +      +
     37A  GLU*     3.2    26.4    +      -       -      +
     39A  LEU*     1.3    65.9    -      -       -      +
     41A  HIS*     1.3    63.4    +      -       -      +
     43A  CYS*     3.8    17.3    -      -       +      -
     44A  ILE*     3.3    28.4    +      -       +      +
    163A  ILE*     4.0    39.9    -      -       +      -
    166A  TRP*     4.2    24.9    -      +       -      -
    167A  GLN*     4.9     1.6    -      -       -      -
----------------------------------------------------------
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Residues in contact with HIS 41 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     37A  GLU*     2.5    66.6    +      -       +      +
     38A  GLY*     3.7    11.6    -      -       -      +
     39A  LEU      3.2     0.2    -      -       -      -
     40A  PHE*     1.3    73.9    -      -       -      +
     42A  ILE*     1.3    60.5    -      -       -      +
     44A  ILE*     5.0     0.6    -      -       -      +
     45A  ALA*     3.4    24.4    +      -       -      +
    110A  PRO      5.2     3.4    -      -       -      -
    111A  LEU*     3.4    32.4    -      -       +      +
    113A  PHE*     3.8    35.1    -      +       +      -
    130A  TYR*     4.0    19.4    +      +       -      +
    131A  TYR*     5.5     2.8    +      -       -      -
    134A  LEU*     6.2     0.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 42 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     38A  GLY      3.3    18.2    -      -       -      +
     39A  LEU*     3.0    29.0    +      -       +      +
     41A  HIS*     1.3    79.0    -      -       +      +
     43A  CYS*     1.3    64.6    +      -       -      +
     45A  ALA*     4.1     1.9    -      -       -      +
     46A  ALA*     3.2    22.0    +      -       +      +
    113A  PHE*     5.2     9.0    -      -       +      -
    114A  THR*     5.4    13.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with CYS 43 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39A  LEU*     2.6    24.1    +      -       +      +
     40A  PHE*     3.7    18.8    +      -       +      -
     42A  ILE*     1.3    73.4    -      -       -      +
     44A  ILE*     1.3    71.5    +      -       +      +
     46A  ALA*     3.1    16.2    +      -       -      +
     47A  ILE*     3.1    29.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 44 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     40A  PHE*     3.3    20.5    +      -       +      +
     41A  HIS*     5.0     0.7    -      -       -      +
     43A  CYS*     1.3    85.0    -      -       +      +
     45A  ALA*     1.3    57.9    +      -       -      +
     47A  ILE*     2.8    14.6    +      -       +      +
     48A  SER*     2.8    30.2    +      -       -      +
    134A  LEU*     4.3    19.3    -      -       +      +
    159A  THR*     3.8    19.1    -      -       +      -
    160A  HIS*     3.5    33.9    -      -       +      +
    163A  ILE*     3.8    31.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 45 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     41A  HIS      3.4    20.7    +      -       -      +
     42A  ILE*     4.3     2.7    -      -       -      +
     43A  CYS      3.3     0.2    -      -       -      -
     44A  ILE*     1.3    78.6    -      -       -      +
     46A  ALA*     1.3    59.3    +      -       -      +
     48A  SER*     3.4    19.1    +      -       -      +
     49A  LEU*     3.4    17.2    +      -       -      +
    130A  TYR*     4.0    19.9    +      -       +      +
    134A  LEU*     5.4     3.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 46 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     42A  ILE*     3.2    15.1    +      -       +      +
     43A  CYS*     3.1    12.4    +      -       -      +
     45A  ALA*     1.3    76.8    -      -       -      +
     47A  ILE*     1.3    66.8    +      -       +      +
     49A  LEU*     3.8     4.4    +      -       -      +
     50A  VAL*     3.3    26.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 47 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     43A  CYS*     3.2    28.5    -      -       -      +
     44A  ILE*     2.8    18.8    +      -       +      +
     46A  ALA*     1.3    80.9    -      -       +      +
     48A  SER*     1.3    63.0    +      -       -      +
     50A  VAL*     3.2    14.5    +      -       +      +
     51A  VAL*     3.3    19.9    +      -       +      +
    156A  LEU*     3.7    29.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 48 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     44A  ILE*     2.8    16.8    +      -       -      -
     45A  ALA*     3.4    17.7    +      -       -      +
     47A  ILE*     1.3    73.5    -      -       -      +
     49A  LEU*     1.3    64.0    +      -       -      +
     51A  VAL*     4.2     1.3    -      -       -      -
     52A  MET*     3.2    30.9    +      -       -      +
    133A  THR*     4.7     4.4    +      -       -      +
    134A  LEU*     3.8    32.3    -      -       -      -
    137A  PRO*     3.7    14.3    -      -       -      +
    156A  LEU*     6.1     1.8    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 49 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     45A  ALA      3.4    16.0    +      -       -      +
     46A  ALA*     4.3     6.1    -      -       -      +
     47A  ILE      3.2     1.0    -      -       -      -
     48A  SER*     1.3    79.0    +      -       -      +
     50A  VAL*     1.3    65.9    +      -       +      +
     52A  MET*     3.9    13.6    +      -       +      +
     53A  LEU*     3.5    36.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 50 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     46A  ALA      3.3    17.0    -      -       -      +
     47A  ILE*     3.2     9.3    +      -       +      +
     49A  LEU*     1.3    77.6    -      -       +      +
     51A  VAL*     1.3    64.8    +      -       +      +
     53A  LEU*     3.0     9.0    +      -       -      +
     54A  VAL*     2.9    38.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 51 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     47A  ILE*     3.3    24.6    +      -       +      +
     48A  SER*     3.9     0.6    +      -       -      -
     50A  VAL*     1.3    80.2    -      -       +      +
     52A  MET*     1.3    61.4    +      -       -      +
     54A  VAL*     3.4     8.7    +      -       +      +
     55A  LEU*     3.3    33.5    +      -       +      +
    137A  PRO*     3.9    26.7    -      -       +      +
    141A  CYS*     5.3     3.4    -      -       -      -
    152A  LEU*     4.6    33.0    -      -       +      -
    156A  LEU*     4.3    21.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with MET 52 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     48A  SER*     3.2    21.8    +      -       -      +
     49A  LEU*     4.1    15.5    -      -       +      +
     50A  VAL      3.2     0.6    -      -       -      -
     51A  VAL*     1.3    78.2    -      -       -      +
     53A  LEU*     1.3    64.2    +      -       +      +
     55A  LEU*     3.5     8.8    +      -       -      +
     56A  ALA*     3.3    15.2    +      -       -      +
     74A  LEU*     3.7    34.4    -      -       +      +
    133A  THR*     4.2    27.1    -      -       +      +
    136A  TYR*     3.5    42.2    -      -       +      -
    137A  PRO*     3.7     8.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 53 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     49A  LEU*     3.5    28.9    -      -       +      +
     50A  VAL*     3.0     9.8    +      -       -      +
     52A  MET*     1.3    81.0    -      -       +      +
     54A  VAL*     1.3    64.3    +      -       -      +
     55A  LEU      3.3     0.7    -      -       -      -
     56A  ALA*     3.3    15.0    +      -       +      +
     57A  ILE*     3.3    28.0    +      -       +      +
     74A  LEU*     5.7     3.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 54 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     50A  VAL*     2.9    33.2    +      -       +      +
     51A  VAL*     3.7    12.1    -      -       +      +
     52A  MET      3.3     0.2    -      -       -      -
     53A  LEU*     1.3    77.5    -      -       -      +
     55A  LEU*     1.3    57.6    +      -       +      +
     57A  ILE*     3.0    28.6    +      -       +      +
     58A  LEU*     3.1    30.1    +      -       +      +
    148A  VAL*     5.1     2.2    -      -       +      -
    152A  LEU*     4.5    20.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 55 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     51A  VAL*     3.3    27.5    +      -       +      +
     52A  MET*     3.7    10.5    -      -       -      +
     53A  LEU      3.3     0.2    -      -       -      -
     54A  VAL*     1.3    76.8    -      -       +      +
     56A  ALA*     1.3    63.3    +      -       -      +
     58A  LEU*     3.9    14.8    -      -       +      +
     59A  ALA*     3.3    22.7    +      -       -      +
     74A  LEU*     5.6     3.1    -      -       +      -
     75A  LEU*     3.7    26.2    -      -       +      +
    136A  TYR*     5.9     1.3    -      -       +      -
    137A  PRO*     5.3     2.9    -      -       +      +
    140A  ALA*     3.7    34.5    -      -       +      +
    141A  CYS*     5.0     6.1    -      -       -      +
    144A  LEU*     3.7    30.7    -      -       +      -
    148A  VAL*     5.7     3.4    -      -       +      -
    149A  GLY*     6.1     2.9    -      -       -      -
    152A  LEU*     5.7     3.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 56 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     52A  MET      3.3    12.7    +      -       -      +
     53A  LEU*     3.5    21.3    -      -       +      +
     54A  VAL      3.2     0.6    -      -       -      -
     55A  LEU*     1.3    76.8    -      -       -      +
     57A  ILE*     1.3    64.2    +      -       +      +
     59A  ALA*     3.9     5.9    +      -       -      +
     60A  ARG*     3.7    27.5    +      -       -      +
     73A  GLY      5.1     9.0    -      -       -      +
     74A  LEU*     4.9    12.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 57 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     53A  LEU*     3.3    16.6    -      -       +      +
     54A  VAL*     3.0    17.8    +      -       +      +
     56A  ALA*     1.3    78.3    -      -       +      +
     58A  LEU*     1.3    62.3    +      -       +      +
     60A  ARG*     3.1    22.1    +      -       +      +
     61A  ARG*     3.3    46.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 58 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     54A  VAL*     3.1    23.1    +      -       +      +
     55A  LEU*     4.1    21.3    -      -       +      +
     56A  ALA      3.5     0.2    -      -       -      -
     57A  ILE*     1.3    78.6    -      -       +      +
     59A  ALA*     1.3    57.9    +      -       -      +
     61A  ARG*     3.0    40.1    +      -       +      +
     62A  GLN*     3.1    35.0    +      -       +      +
     64A  LEU*     5.6     0.2    -      -       -      -
    144A  LEU*     4.5    12.3    -      -       +      -
    146A  ASN*     5.1     3.6    -      -       -      +
    148A  VAL*     3.8    36.3    -      -       +      -
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Residues in contact with ALA 59 (chain A). Click here for Legend to table.
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                                  Specific contacts
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     Residue       Dist    Surf   HB    Arom    Phob    DC
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     55A  LEU      3.3    17.8    +      -       -      +
     56A  ALA*     4.2     5.4    -      -       -      +
     57A  ILE      3.2     1.0    -      -       -      -
     58A  LEU*     1.3    77.4    -      -       -      +
     60A  ARG*     1.3    59.0    +      -       +      +
     61A  ARG      3.2     1.1    +      -       -      -
     62A  GLN      3.9     5.8    +      -       -      -
     63A  LYS*     4.0     8.0    +      -       -      +
     64A  LEU*     4.2    18.8    -      -       +      -
     68A  GLN*     3.0    41.7    +      -       +      +
     73A  GLY      4.5    10.5    -      -       -      +
     75A  LEU*     4.6     7.0    -      -       +      -
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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
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  Atomic class           I  II  III   IV   V   VI  VII  VIII
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   I  (Hydrophilic)      +   +    +    -   +   +    +    +
  II  (Acceptor)         +   -    +    -   +   +    +    -
 III  (Donor)            +   +    -    -   +   +    -    +
  IV  (Hydrophobic)      -   -    -    +   +   +    +    +
   V  (Aromatic)         +   +    +    +   +   +    +    +
  VI  (Neutral)          +   +    +    +   +   +    +    +
 VII  (Neutral-donor)    +   +    -    +   +   +    -    +
VIII  (Neutral-acceptor) +   -    +    +   +   +    +    -
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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