Contacts of the helix formed by residues 11 - 40 (chain A) in PDB entry 3SN6


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 ASP 11 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     10A  GLU*     1.3    84.4    -      -       +      +
     12A  GLN*     1.3    60.0    +      -       +      +
     13A  ARG      3.1     2.5    -      -       -      -
     14A  ASN*     2.8    32.6    +      -       +      +
     15A  GLU*     2.9    22.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 12 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      9A  THR      3.0    18.3    +      -       -      +
     10A  GLU*     3.2    23.5    -      -       -      +
     11A  ASP*     1.3    79.0    -      -       +      +
     13A  ARG*     1.3    62.8    +      -       -      +
     15A  GLU*     3.0    17.5    +      -       -      +
     16A  GLU*     2.9    39.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 13 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      9A  THR*     2.9    57.5    +      -       -      +
     10A  GLU      3.9     6.0    -      -       -      +
     11A  ASP      3.1     0.2    -      -       -      -
     12A  GLN*     1.3    76.2    -      -       -      +
     14A  ASN*     1.3    66.1    +      -       -      +
     16A  GLU*     3.8     9.4    +      -       -      +
     17A  LYS*     3.5    17.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 14 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     10A  GLU      4.4     9.8    +      -       -      -
     11A  ASP*     2.8    18.4    +      -       +      +
     13A  ARG*     1.3    82.5    -      -       -      +
     15A  GLU*     1.3    59.8    +      -       +      +
     17A  LYS*     3.1    14.6    +      -       -      +
     18A  ALA*     2.9    25.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 15 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     11A  ASP*     2.9    23.2    +      -       +      +
     12A  GLN*     3.0    18.9    +      -       -      +
     14A  ASN*     1.3    73.4    -      -       +      +
     16A  GLU*     1.3    69.0    +      -       -      +
     18A  ALA*     2.9    19.8    +      -       +      +
     19A  GLN*     2.9    15.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 16 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12A  GLN*     2.9    31.4    +      -       +      +
     13A  ARG*     3.8     8.7    -      -       -      +
     15A  GLU*     1.3    75.5    -      -       -      +
     17A  LYS*     1.3    57.4    -      -       -      +
     19A  GLN*     3.6     8.4    +      -       -      +
     20A  ARG*     3.0    28.8    +      -       -      +
     68B  ARG*     5.9     0.5    +      -       -      -
     86B  THR*     4.3    18.5    -      -       -      +
     88B  ASN*     5.2     2.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 17 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     13A  ARG      3.5    10.4    +      -       -      +
     14A  ASN*     3.1    16.7    +      -       -      +
     16A  GLU*     1.3    75.9    -      -       -      +
     18A  ALA*     1.3    61.0    +      -       -      +
     20A  ARG*     3.1     8.6    -      -       +      +
     21A  GLU*     2.9    54.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 18 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     14A  ASN      2.9    11.9    +      -       -      +
     15A  GLU*     2.9    15.2    +      -       -      +
     17A  LYS*     1.3    73.1    -      -       -      +
     19A  GLN*     1.3    66.0    +      -       -      +
     21A  GLU*     2.9     9.1    +      -       -      +
     22A  ALA*     2.9    23.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 19 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     15A  GLU      2.9    13.4    +      -       -      +
     16A  GLU*     4.1     7.7    -      -       -      +
     18A  ALA*     1.3    75.8    -      -       -      +
     20A  ARG*     1.3    62.0    +      -       -      +
     22A  ALA*     4.0     6.6    -      -       +      +
     23A  ASN*     2.9    27.3    +      -       -      +
     68B  ARG*     4.9     0.9    +      -       -      -
     69B  LEU*     5.3     0.4    -      -       -      +
     83B  ASP*     3.2    21.5    +      -       -      +
     86B  THR*     3.0    27.3    +      -       -      +
     88B  ASN*     3.2    25.5    +      -       +      +
     89B  LYS      5.2     4.3    -      -       -      +
     90B  VAL*     3.7    23.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 20 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     16A  GLU      3.0    16.8    +      -       -      +
     17A  LYS*     3.1    17.5    -      -       +      +
     19A  GLN*     1.3    77.9    -      -       -      +
     21A  GLU*     1.3    64.3    +      -       -      +
     23A  ASN*     3.5    12.4    +      -       -      +
     24A  LYS*     2.9    31.0    +      -       +      +
     88B  ASN*     4.5    11.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 21 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     17A  LYS*     2.9    47.5    +      -       +      +
     18A  ALA*     2.9     6.9    +      -       -      +
     20A  ARG*     1.3    79.5    -      -       -      +
     22A  ALA*     1.3    61.1    +      -       -      +
     24A  LYS*     2.8    26.5    +      -       -      +
     25A  LYS*     2.9    18.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 22 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     18A  ALA      2.9    14.5    +      -       -      +
     19A  GLN*     4.0     7.9    -      -       +      +
     21A  GLU*     1.3    74.3    -      -       -      +
     23A  ASN*     1.3    63.2    +      -       -      +
     25A  LYS*     3.2    11.4    +      -       -      +
     26A  ILE*     3.0    31.8    +      -       +      +
     89B  LYS      4.9     5.8    -      -       -      +
     90B  VAL*     5.7     2.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 23 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19A  GLN      2.9    19.9    +      -       -      +
     20A  ARG*     3.5    11.2    +      -       -      +
     22A  ALA*     1.3    76.5    -      -       -      +
     24A  LYS*     1.3    60.7    +      -       -      +
     26A  ILE*     3.4     4.8    +      -       -      +
     27A  GLU*     2.9    54.5    +      -       -      +
     87B  THR      4.7     1.0    -      -       -      +
     88B  ASN*     3.5    19.0    +      -       -      +
     89B  LYS*     2.8    50.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 24 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     20A  ARG*     2.9    19.8    +      -       -      +
     21A  GLU*     2.8    28.3    +      -       -      +
     23A  ASN*     1.3    73.9    -      -       -      +
     25A  LYS*     1.3    62.8    +      -       +      +
     27A  GLU*     3.1    10.0    +      -       -      +
     28A  LYS*     2.9    20.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 25 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     21A  GLU*     2.9    16.7    +      -       +      +
     22A  ALA*     3.2     9.4    +      -       -      +
     24A  LYS*     1.3    75.9    -      -       +      +
     26A  ILE*     1.3    64.8    +      -       +      +
     28A  LYS*     2.8    25.6    +      -       +      +
     29A  GLN*     3.0    14.7    +      -       -      +
    112A  ASN*     3.8    39.4    +      -       -      +
    113A  LEU*     6.2     0.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 26 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     22A  ALA*     3.0    21.0    +      -       +      +
     23A  ASN*     3.6     6.7    -      -       -      +
     25A  LYS*     1.3    76.0    -      -       +      +
     27A  GLU*     1.3    63.2    +      -       -      +
     29A  GLN*     3.4     5.5    +      -       -      +
     30A  LEU*     2.9    36.8    +      -       +      +
     89B  LYS*     3.2    46.9    -      -       +      +
     90B  VAL      4.1    13.7    -      -       -      +
     91B  HIS*     4.1     9.9    -      -       -      +
     92B  ALA*     3.7    27.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 27 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     23A  ASN*     2.9    41.4    +      -       -      +
     24A  LYS*     3.2    11.4    -      -       -      +
     26A  ILE*     1.3    75.6    -      -       -      +
     28A  LYS*     1.3    58.0    +      -       -      +
     30A  LEU*     3.4     9.9    +      -       -      +
     31A  GLN*     2.9    28.8    +      -       -      +
     52B  ARG      4.9     3.3    -      -       -      +
     89B  LYS*     3.3    27.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 28 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24A  LYS      2.9    10.8    +      -       -      +
     25A  LYS*     2.8    20.3    +      -       +      +
     27A  GLU*     1.3    73.9    -      -       -      +
     29A  GLN*     1.3    66.8    +      -       -      +
     31A  GLN*     2.7    21.2    +      -       +      +
     32A  LYS*     3.0    46.2    +      -       +      +
    112A  ASN*     6.2     0.2    -      -       -      +
    135A  MET*     6.0     4.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 29 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     25A  LYS      3.0     7.8    +      -       -      +
     26A  ILE*     4.0     7.4    -      -       -      +
     28A  LYS*     1.3    82.7    -      -       +      +
     30A  LEU*     1.3    53.6    +      -       -      +
     32A  LYS*     3.0    17.9    +      -       +      +
     33A  ASP*     2.5    46.1    +      -       -      +
    170A  GLN*     4.0    31.2    +      -       -      +
     78B  LYS*     4.6    11.8    -      -       -      +
     94B  PRO*     6.1     0.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 30 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     26A  ILE*     2.9    31.1    +      -       +      +
     27A  GLU*     3.5     9.6    -      -       -      +
     29A  GLN*     1.3    74.1    -      -       -      +
     31A  GLN*     1.3    61.1    +      -       -      +
     33A  ASP*     2.9    10.2    +      -       +      +
     34A  LYS*     2.9    30.5    +      -       -      +
     53B  GLY*     3.6    26.9    -      -       -      +
     55B  LEU*     4.4    14.2    -      -       +      +
     78B  LYS*     4.2    32.1    -      -       +      +
     80B  ILE*     4.3     6.7    -      -       +      -
     89B  LYS*     4.0    25.8    -      -       -      +
     92B  ALA*     5.1     4.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLN 31 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27A  GLU      2.9    13.2    +      -       -      +
     28A  LYS*     2.7    19.6    +      -       -      +
     30A  LEU*     1.3    71.7    -      -       -      +
     32A  LYS*     1.3    60.8    +      -       +      +
     33A  ASP      3.5     0.3    +      -       -      -
     34A  LYS*     3.7    34.0    +      -       -      +
     35A  GLN*     3.8    12.5    +      -       -      +
    147R  LYS*     6.0     3.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 32 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     28A  LYS*     3.0    50.0    +      -       +      +
     29A  GLN*     3.0    19.3    +      -       +      +
     31A  GLN*     1.3    81.4    -      -       +      +
     33A  ASP*     1.3    59.1    +      -       -      +
     35A  GLN*     3.8     6.1    +      -       -      +
     36A  VAL*     3.4    19.5    +      -       -      +
    104A  GLU*     5.9     1.4    +      -       -      -
    135A  MET*     5.5     8.7    -      -       -      +
    136A  ASN*     5.7     7.9    -      -       -      -
----------------------------------------------------------
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Residues in contact with ASP 33 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     29A  GLN*     2.5    45.5    +      -       -      +
     30A  LEU*     2.9    12.9    +      -       +      +
     32A  LYS*     1.3    77.0    -      -       -      +
     34A  LYS*     1.3    64.4    +      -       -      +
     35A  GLN      3.2     0.4    -      -       -      -
     36A  VAL*     3.0    11.9    -      -       -      +
     37A  TYR*     2.9    26.2    +      -       -      +
     55B  LEU*     3.9    14.4    -      -       +      -
     78B  LYS*     3.6    28.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 34 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30A  LEU      2.9    11.3    +      -       -      +
     31A  GLN*     4.1    29.6    +      -       -      +
     32A  LYS      3.5     0.2    -      -       -      -
     33A  ASP*     1.3    75.6    -      -       -      +
     35A  GLN*     1.3    58.7    +      -       -      +
     37A  TYR*     4.4     0.2    -      -       -      -
     38A  ARG*     2.9    58.8    +      -       +      +
     55B  LEU*     3.5    36.1    -      -       +      +
     67R  VAL*     5.9     3.8    -      -       -      +
    147R  LYS*     4.7    22.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 35 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31A  GLN*     3.8    10.1    +      -       -      +
     32A  LYS*     3.9    10.3    -      -       -      +
     33A  ASP      3.2     0.6    -      -       -      -
     34A  LYS*     1.3    83.0    -      -       -      +
     36A  VAL*     1.3    57.2    +      -       -      +
     38A  ARG*     3.8     2.7    -      -       -      +
     39A  ALA*     2.9    30.4    +      -       -      +
    142R  GLN      5.4     0.9    -      -       -      +
    143R  SER*     5.2     7.8    -      -       -      +
    146R  THR*     6.0     6.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 36 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     32A  LYS      3.4    13.4    +      -       -      +
     33A  ASP*     3.0    28.7    -      -       +      +
     35A  GLN*     1.3    77.0    -      -       -      +
     37A  TYR*     1.3    56.0    +      -       -      +
     39A  ALA*     3.1     8.3    +      -       -      +
     40A  THR*     2.6    39.8    +      -       -      +
    218A  ASN*     4.3    14.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 37 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     33A  ASP      2.9    19.3    +      -       -      +
     34A  LYS      3.8     1.8    -      -       -      +
     36A  VAL*     1.3    78.6    -      -       +      +
     38A  ARG*     1.3    71.2    +      -       +      +
     40A  THR*     2.9    34.1    +      -       -      +
     42A  ARG*     2.9    45.2    +      -       +      +
    240A  ASP*     5.2     1.6    -      -       -      +
     55B  LEU*     3.9    41.7    -      -       +      -
     56B  ALA*     3.2    18.7    -      -       +      +
     75B  GLN      4.9     0.2    -      -       -      -
     76B  ASP*     4.2    21.5    -      -       +      -
     98B  SER*     6.4     0.9    -      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 38 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     34A  LYS*     2.9    48.2    +      -       +      +
     35A  GLN*     4.0     3.1    -      -       -      +
     37A  TYR*     1.3    85.8    -      -       +      +
     39A  ALA*     1.3    58.7    +      -       -      +
     40A  THR      3.2     6.0    +      -       -      +
     41A  HIS*     5.0     2.8    -      -       -      -
     55B  LEU      5.8     3.0    +      -       -      -
     67R  VAL*     5.0    16.4    -      -       -      +
    142R  GLN*     3.8    39.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 39 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     35A  GLN      2.9    18.9    +      -       -      +
     36A  VAL*     3.4    10.5    -      -       -      +
     37A  TYR      3.1     0.4    -      -       -      -
     38A  ARG*     1.3    76.4    -      -       -      +
     40A  THR*     1.3    61.2    +      -       -      +
     41A  HIS*     3.5    15.2    +      -       -      -
    217A  VAL*     4.8     2.3    -      -       -      +
    218A  ASN*     4.0    19.4    +      -       -      +
    139R  PHE      5.2     2.4    -      -       -      +
    142R  GLN*     5.3     0.2    -      -       -      -
    143R  SER*     3.6    37.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 40 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     36A  VAL*     2.6    28.1    +      -       -      +
     37A  TYR*     2.9    20.8    +      -       -      +
     38A  ARG      3.7     5.7    -      -       -      +
     39A  ALA*     1.3    81.8    -      -       -      +
     41A  HIS*     1.3    74.6    +      -       -      +
     42A  ARG*     4.1     7.8    +      -       +      +
    211A  LYS*     5.7     2.5    -      -       +      -
    218A  ASN*     3.6    21.1    -      -       +      +
    219A  PHE      3.9     3.8    -      -       -      +
    220A  HIS*     3.7    34.8    -      -       +      +
    242A  THR*     5.2     1.2    -      -       -      +
----------------------------------------------------------
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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