Contacts of the helix formed by residues 8 - 34 (chain A) in PDB entry 4KXW


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 8 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      6A  LYS      3.6     2.0    +      -       -      +
      7A  PRO*     1.3    75.8    -      -       -      +
      9A  GLN*     1.3    58.2    +      -       -      +
     10A  GLN*     3.4    18.2    +      -       -      +
     11A  LYS*     2.8    36.2    +      -       -      +
     12A  LEU*     2.9    28.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 9 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      8A  ASP*     1.3    73.2    -      -       -      +
     10A  GLN*     1.3    58.0    +      -       +      +
     12A  LEU*     3.4    27.2    +      -       -      +
     13A  GLN*     2.8    30.2    +      -       -      +
     16A  LYS*     4.9    11.5    -      -       -      +
    222A  GLU*     4.4     9.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 10 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      8A  ASP*     3.2    16.8    +      -       -      +
      9A  GLN*     1.3    75.9    -      -       +      +
     11A  LYS*     1.3    59.4    +      -       -      +
     13A  GLN*     3.4     6.9    +      -       +      +
     14A  ALA*     2.9    27.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 11 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      7A  PRO*     3.8    22.2    -      -       +      -
      8A  ASP*     2.8    26.2    +      -       -      +
     10A  GLN*     1.3    72.3    -      -       -      +
     12A  LEU*     1.3    57.3    +      -       -      +
     14A  ALA*     3.2     5.5    +      -       +      +
     15A  LEU*     2.9    35.0    +      -       +      +
     53A  PHE      3.4    23.4    +      -       -      -
     54A  HIS*     3.1    26.6    +      -       +      +
    284A  ILE*     3.8    30.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 12 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      7A  PRO*     3.6    28.9    -      -       +      +
      8A  ASP      2.9    21.5    +      -       -      +
      9A  GLN*     3.4    36.1    -      -       -      +
     11A  LYS*     1.3    75.8    -      -       -      +
     13A  GLN*     1.3    61.8    +      -       -      +
     15A  LEU*     3.1     7.0    +      -       +      +
     16A  LYS*     3.0    32.1    +      -       -      +
    221A  VAL*     3.7    26.5    -      -       +      +
    222A  GLU*     3.6    40.6    -      -       +      +
    225A  CYS*     4.4     4.5    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLN 13 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      9A  GLN*     2.8    21.4    +      -       -      +
     10A  GLN*     3.8     7.6    -      -       +      +
     12A  LEU*     1.3    72.9    -      -       -      +
     14A  ALA*     1.3    58.0    +      -       -      +
     16A  LYS*     3.2    30.5    +      -       -      +
     17A  ASP*     2.8    56.4    +      -       -      +
    277A  GLN      4.1     5.9    +      -       -      -
    279A  GLN*     3.5    49.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 14 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     10A  GLN      2.9    17.4    +      -       -      +
     11A  LYS*     3.2     8.7    +      -       +      +
     13A  GLN*     1.3    75.4    -      -       -      +
     15A  LEU*     1.3    53.6    +      -       -      +
     17A  ASP*     3.4    11.8    +      -       -      +
     18A  THR*     2.7    37.1    +      -       -      -
     21A  ARG*     4.3     2.4    +      -       -      +
    280A  SER*     6.5     0.2    -      -       -      -
    282A  LYS      5.2     8.1    -      -       -      +
    284A  ILE*     3.8    22.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 15 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     11A  LYS*     2.9    32.2    +      -       +      +
     12A  LEU*     3.1    13.4    +      -       +      +
     14A  ALA*     1.3    72.9    -      -       -      +
     16A  LYS*     1.3    59.6    +      -       -      +
     18A  THR*     3.3     5.1    +      -       -      +
     19A  ALA*     2.9    25.3    +      -       -      +
     49A  ALA*     3.5    37.7    -      -       +      +
     50A  VAL*     4.2     7.2    -      -       +      -
     53A  PHE*     3.9    13.7    -      -       +      +
     54A  HIS*     4.3     5.6    -      -       +      -
    221A  VAL*     4.0    13.9    -      -       +      +
    225A  CYS*     3.6    31.2    -      -       -      -
    284A  ILE*     3.6    20.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 16 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      9A  GLN*     4.9    11.3    -      -       -      +
     12A  LEU*     3.0    26.1    +      -       -      +
     13A  GLN*     3.2    31.2    +      -       -      +
     15A  LEU*     1.3    72.3    -      -       -      +
     17A  ASP*     1.3    66.1    +      -       -      +
     19A  ALA*     3.2     7.5    +      -       -      +
     20A  ASN*     2.9    34.7    +      -       -      +
     46A  GLU*     5.6     3.6    -      -       +      +
    221A  VAL*     3.9    32.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASP 17 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     13A  GLN*     2.8    39.8    +      -       -      +
     14A  ALA*     3.5     8.6    -      -       -      +
     16A  LYS*     1.3    74.9    -      -       -      +
     18A  THR*     1.3    57.2    +      -       -      +
     20A  ASN*     3.3     2.9    +      -       -      +
     21A  ARG*     2.9    44.4    +      -       -      +
    277A  GLN      3.9     0.9    -      -       -      +
    278A  ILE*     3.5    22.1    -      -       +      +
    279A  GLN*     2.9    27.2    +      -       -      +
    280A  SER*     3.0    29.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 18 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     14A  ALA      2.7    24.6    +      -       -      -
     15A  LEU*     3.5     7.4    -      -       -      -
     17A  ASP*     1.3    76.3    -      -       -      +
     19A  ALA*     1.3    63.6    +      -       -      +
     21A  ARG*     3.1    20.7    +      -       -      +
     22A  LEU*     2.9    32.7    +      -       +      +
     49A  ALA*     3.9    11.9    -      -       +      -
     53A  PHE*     3.8    31.4    -      -       +      -
     88A  GLU*     3.9    16.9    +      -       +      +
    284A  ILE*     3.8    16.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 19 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     15A  LEU      2.9    13.5    +      -       -      +
     16A  LYS      3.2     9.2    +      -       -      +
     18A  THR*     1.3    74.9    -      -       -      +
     20A  ASN*     1.3    57.4    +      -       -      +
     22A  LEU*     3.2     6.3    +      -       -      +
     23A  ARG*     3.0    33.4    +      -       -      +
     45A  ALA*     3.5    34.5    -      -       -      +
     46A  GLU*     3.8    27.6    -      -       +      +
     49A  ALA*     3.8     2.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 20 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     16A  LYS*     2.9    26.8    +      -       -      +
     17A  ASP*     3.8     0.8    +      -       -      +
     19A  ALA*     1.3    73.9    -      -       -      +
     21A  ARG*     1.3    64.5    +      -       -      +
     23A  ARG*     3.0    33.4    +      -       -      +
     24A  ILE*     3.0    27.2    +      -       -      +
     46A  GLU*     5.6     0.4    +      -       -      -
    247A  GLY*     6.0     0.3    -      -       -      -
    274A  ILE*     3.6    20.1    -      -       +      +
    277A  GLN*     4.2    29.7    +      -       -      +
    278A  ILE*     3.7    19.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 21 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     14A  ALA*     4.3     1.8    +      -       -      +
     17A  ASP*     2.9    20.8    +      -       -      +
     18A  THR*     3.5    25.4    +      -       -      +
     20A  ASN*     1.3    75.1    -      -       -      +
     22A  LEU*     1.3    58.0    +      -       -      +
     24A  ILE*     3.3     7.7    +      -       +      +
     25A  SER*     2.9    30.1    +      -       -      -
     88A  GLU*     2.8    28.7    +      -       -      +
    278A  ILE*     3.8    25.3    -      -       +      +
    280A  SER      2.9    25.1    +      -       -      -
    281A  LYS*     3.8    15.7    -      -       -      +
    282A  LYS      3.5    18.6    +      -       -      -
    283A  LYS*     3.8    15.9    -      -       -      +
    284A  ILE*     5.1     0.4    -      -       -      +
   1010A  EDO      3.4    26.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 22 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     18A  THR*     2.9    22.8    +      -       +      +
     19A  ALA*     3.2     6.0    +      -       -      +
     21A  ARG*     1.3    76.4    -      -       -      +
     23A  ARG*     1.3    62.1    +      -       -      +
     25A  SER*     3.4     1.7    +      -       -      -
     26A  SER*     2.9    30.3    +      -       -      -
     45A  ALA*     3.9    20.9    -      -       +      +
     48A  MET*     4.0     5.6    -      -       +      -
     49A  ALA*     3.9    14.8    -      -       +      +
     81A  ILE*     3.7    17.8    -      -       +      +
     84A  ALA*     3.7    31.7    -      -       +      +
     85A  VAL*     3.6    37.0    -      -       +      +
     88A  GLU*     4.6     7.4    -      -       +      -
   1010A  EDO      4.4     7.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 23 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19A  ALA*     3.0    18.7    +      -       -      +
     20A  ASN*     3.0    35.9    +      -       -      +
     22A  LEU*     1.3    74.9    -      -       -      +
     24A  ILE*     1.4    62.3    +      -       -      +
     26A  SER*     3.2     4.7    +      -       -      -
     27A  ILE*     3.0    29.0    +      -       -      +
     42A  CYS*     3.0    40.8    +      -       -      +
     45A  ALA*     3.7    15.7    -      -       +      +
     46A  GLU*     2.8    44.0    +      -       -      -
     81A  ILE*     5.5     1.1    -      -       -      -
    246A  ARG*     2.8    42.3    +      -       -      +
    247A  GLY*     4.2     5.6    -      -       -      -
    274A  ILE*     4.2    19.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 24 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     20A  ASN      3.0    15.8    +      -       -      +
     21A  ARG*     3.7     9.6    -      -       +      +
     23A  ARG*     1.4    75.6    -      -       -      +
     25A  SER*     1.3    60.0    +      -       -      +
     27A  ILE*     3.3     3.5    +      -       -      +
     28A  GLN*     2.8    54.0    +      -       +      +
    271A  ILE*     3.9    27.8    -      -       +      +
    274A  ILE*     3.7    29.8    -      -       +      -
    275A  TYR*     3.8    29.4    -      -       +      +
    278A  ILE*     3.9    15.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 25 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     21A  ARG      2.9    16.5    +      -       -      -
     22A  LEU      3.8     0.4    -      -       -      -
     24A  ILE*     1.3    77.8    -      -       -      +
     26A  SER*     1.4    56.8    +      -       -      +
     28A  GLN*     3.2    13.6    +      -       -      +
     29A  ALA*     2.8    32.2    +      -       -      +
     80A  PRO      4.9     1.8    +      -       -      -
     84A  ALA*     3.6    22.3    -      -       -      +
     97A  LEU*     3.3    30.2    -      -       -      +
     98A  LEU*     5.6     0.2    -      -       -      +
   1010A  EDO      4.0    10.5    -      -       -      -
----------------------------------------------------------
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Residues in contact with SER 26 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     22A  LEU      2.9    21.7    +      -       -      -
     23A  ARG*     3.2     5.8    +      -       -      -
     25A  SER*     1.4    75.4    -      -       -      +
     27A  ILE*     1.3    60.5    +      -       -      +
     29A  ALA*     4.1     0.3    -      -       -      +
     30A  THR*     2.8    33.7    +      -       -      +
     38A  PRO*     4.2     6.0    -      -       -      +
     41A  CYS*     3.3    37.9    -      -       -      +
     42A  CYS*     5.4     0.7    -      -       -      -
     80A  PRO*     4.0    10.7    +      -       -      -
     81A  ILE*     3.5    19.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 27 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     23A  ARG      3.0    19.0    +      -       -      +
     24A  ILE*     3.7     4.5    -      -       -      +
     26A  SER*     1.3    74.3    -      -       -      +
     28A  GLN*     1.3    65.1    +      -       -      +
     30A  THR*     3.4     5.2    +      -       -      -
     31A  THR*     2.9    32.8    +      -       -      +
     38A  PRO*     4.3    15.9    -      -       +      -
     42A  CYS*     4.5     4.9    -      -       -      -
    248A  ILE*     4.1    17.5    -      -       +      -
    262A  LEU*     4.2    13.7    -      -       +      -
    267A  ALA*     3.8    26.9    -      -       +      -
    270A  ILE*     3.9    14.8    -      -       +      -
    271A  ILE*     3.9    12.8    -      -       +      -
    274A  ILE*     3.9    26.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLN 28 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24A  ILE*     2.8    36.7    +      -       -      +
     25A  SER*     3.7    17.5    +      -       -      +
     27A  ILE*     1.3    73.9    -      -       -      +
     29A  ALA*     1.3    58.6    +      -       -      +
     31A  THR*     3.9     3.9    -      -       -      -
     32A  ALA*     2.9    30.8    +      -       -      +
     98A  LEU*     3.9    21.2    -      -       +      +
    271A  ILE*     3.6    23.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 29 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     25A  SER*     2.8    18.4    +      -       -      +
     26A  SER*     4.1     3.8    -      -       -      +
     28A  GLN*     1.3    78.7    -      -       -      +
     30A  THR*     1.4    58.2    +      -       -      +
     32A  ALA*     3.4     6.0    +      -       -      +
     33A  ALA*     2.9    28.6    +      -       -      +
     80A  PRO*     4.8     6.3    -      -       +      +
     97A  LEU*     3.3    32.1    -      -       +      +
     98A  LEU*     4.5     4.8    -      -       +      +
    100A  LEU*     3.7    18.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with THR 30 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     26A  SER      2.8    22.6    +      -       -      +
     27A  ILE*     3.4     4.2    +      -       -      -
     29A  ALA*     1.4    72.6    -      -       -      +
     31A  THR*     1.3    63.2    +      -       -      +
     34A  GLY*     2.8    24.8    +      -       -      -
     35A  SER      3.4    24.3    +      -       -      +
     36A  GLY*     3.9     0.7    -      -       -      -
     37A  HIS      3.8    16.4    -      -       -      +
     38A  PRO*     3.5    28.0    -      -       +      +
     80A  PRO*     3.8    15.7    -      -       +      -
    100A  LEU*     3.7    19.3    -      -       +      -
    261A  PRO*     3.7     7.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 31 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27A  ILE*     2.9    20.2    +      -       -      +
     28A  GLN*     4.0     3.6    -      -       -      -
     30A  THR*     1.3    77.0    +      -       -      +
     32A  ALA*     1.3    62.4    +      -       -      +
     34A  GLY*     3.3    10.7    +      -       -      -
    261A  PRO*     4.5     3.3    -      -       -      +
    262A  LEU*     2.9    35.4    +      -       -      +
    264A  LYS*     3.3    45.2    +      -       +      +
    267A  ALA*     3.5    19.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 32 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     28A  GLN      2.9    19.8    +      -       -      +
     29A  ALA*     3.6     5.4    -      -       -      +
     31A  THR*     1.3    78.2    -      -       -      +
     33A  ALA*     1.3    62.5    +      -       -      +
     98A  LEU*     3.7    28.0    -      -       +      +
    102A  LYS*     5.9     3.8    -      -       -      -
    264A  LYS*     4.3     9.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 33 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     29A  ALA      2.9    16.6    +      -       -      +
     30A  THR      3.8     0.2    -      -       -      +
     32A  ALA*     1.3    77.5    -      -       -      +
     34A  GLY*     1.3    61.6    +      -       -      +
     35A  SER*     3.6    20.9    +      -       -      +
     98A  LEU      5.1     0.6    +      -       -      -
    100A  LEU*     3.5    26.2    +      -       +      +
    101A  ARG*     4.1    15.5    -      -       +      -
    102A  LYS*     6.3     2.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 34 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30A  THR      2.8     8.3    +      -       -      -
     31A  THR      3.3     7.5    +      -       -      -
     32A  ALA      3.3     3.4    -      -       -      -
     33A  ALA*     1.3    76.9    -      -       -      +
     35A  SER*     1.3    61.1    +      -       -      +
    261A  PRO*     3.7    19.2    -      -       -      +
----------------------------------------------------------
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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