Contacts of the helix formed by residues 7 - 35 (chain C) in PDB entry 3ITX


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 ALA 7 (chain C).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      4C  PHE*     4.4     3.5    +      -       -      -
      5C  ARG      4.1     2.0    +      -       -      -
      6C  ILE*     1.3    75.1    -      -       -      +
      8C  GLN*     1.3    65.1    -      -       -      +
      9C  ASP*     2.9    21.8    -      -       -      +
     10C  VAL*     3.0    26.7    +      -       +      +
     11C  VAL*     3.3    10.9    +      -       -      +
    409C  SER*     5.5     1.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLN 8 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      4C  PHE*     3.0    54.9    -      -       +      +
      6C  ILE      3.3     2.5    +      -       -      +
      7C  ALA*     1.3    71.6    -      -       -      +
      9C  ASP*     1.3    56.8    +      -       -      +
     11C  VAL*     3.3    10.1    +      -       -      +
     12C  ALA*     3.0    29.6    +      -       -      +
     90C  GLN*     5.4     1.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 9 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      7C  ALA*     2.9    34.1    -      -       -      +
      8C  GLN*     1.3    78.4    -      -       -      +
     10C  VAL*     1.3    61.9    +      -       -      +
     12C  ALA*     3.8     6.0    -      -       -      +
     13C  ARG*     3.0    53.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 10 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      6C  ILE*     4.7     3.6    -      -       +      -
      7C  ALA*     3.0    18.1    +      -       +      +
      9C  ASP*     1.3    88.8    -      -       -      +
     11C  VAL*     1.3    66.2    +      -       -      +
     13C  ARG*     3.2    22.6    +      -       -      +
     14C  GLU*     2.9    33.6    +      -       +      +
    405C  THR*     4.1    26.5    -      -       +      +
    408C  ALA*     4.3     7.4    -      -       +      +
    409C  SER*     4.1    24.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 11 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      6C  ILE*     3.9    18.6    -      -       +      -
      7C  ALA      3.3    12.5    +      -       -      +
      8C  GLN*     3.3    10.1    +      -       -      +
     10C  VAL*     1.3    77.0    -      -       -      +
     12C  ALA*     1.3    62.3    +      -       -      +
     14C  GLU*     3.9     1.0    -      -       -      +
     15C  ASN*     3.0    48.0    +      -       -      +
     90C  GLN*     4.0    15.3    -      -       -      +
     91C  LEU*     4.1    12.3    -      -       +      -
    397C  GLY      4.3     9.0    -      -       -      +
    398C  GLY      3.7    18.6    -      -       -      +
    399C  ALA*     4.5     4.3    -      -       -      -
    405C  THR*     4.0     9.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 12 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      8C  GLN      3.0    16.8    +      -       -      +
      9C  ASP*     3.8     6.7    -      -       -      +
     11C  VAL*     1.3    77.6    -      -       -      +
     13C  ARG*     1.3    57.8    +      -       -      +
     15C  ASN*     3.2     7.1    +      -       -      +
     16C  ASP*     2.8    42.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 13 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      9C  ASP*     3.0    42.1    +      -       -      +
     10C  VAL*     3.7    23.7    -      -       -      +
     12C  ALA*     1.3    78.0    -      -       -      +
     14C  GLU*     1.3    71.0    +      -       -      +
     16C  ASP*     3.4     7.7    +      -       -      +
     17C  ARG*     3.1    45.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 14 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     10C  VAL*     2.9    23.4    +      -       +      +
     11C  VAL      4.1     1.3    -      -       -      +
     13C  ARG*     1.3    85.3    +      -       -      +
     15C  ASN*     1.3    61.5    -      -       -      +
     17C  ARG*     3.2    28.9    +      -       -      -
     18C  ARG*     2.8    60.0    +      -       -      +
    400C  VAL*     5.1     0.2    -      -       -      +
    401C  ASP      5.8     0.6    +      -       -      -
    404C  ALA      5.1     0.7    -      -       -      +
    405C  THR*     3.4    31.0    -      -       -      +
    408C  ALA*     3.9    31.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 15 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     11C  VAL*     3.0    33.2    +      -       -      +
     12C  ALA*     3.2     6.2    +      -       -      +
     14C  GLU*     1.3    76.1    -      -       -      +
     16C  ASP*     1.3    56.6    +      -       -      +
     17C  ARG      3.1     1.3    -      -       -      -
     18C  ARG*     3.0     3.6    +      -       -      +
     19C  ALA*     2.7    37.4    +      -       -      +
    394C  ARG*     4.5    16.6    +      -       +      +
    398C  GLY      3.3    20.4    +      -       -      -
    399C  ALA*     3.5     5.3    -      -       -      +
    400C  VAL*     2.8    44.2    +      -       +      +
    401C  ASP      4.7     0.3    +      -       -      -
    405C  THR*     4.8     0.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with ASP 16 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12C  ALA*     2.8    31.4    +      -       -      +
     13C  ARG*     3.8     6.5    +      -       -      +
     15C  ASN*     1.3    79.2    -      -       -      +
     17C  ARG*     1.3    61.9    +      -       -      +
     18C  ARG      3.2     0.7    +      -       -      -
     19C  ALA*     3.4    19.3    +      -       -      +
     20C  SER*     4.6     2.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 17 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     13C  ARG*     3.1    37.9    +      -       -      +
     14C  GLU*     3.2    36.3    +      -       -      +
     15C  ASN      3.1     0.2    -      -       -      -
     16C  ASP*     1.3    78.1    -      -       -      +
     18C  ARG*     1.3    77.8    +      -       +      +
     20C  SER*     5.3     2.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 18 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     14C  GLU*     2.8    60.3    +      -       -      +
     15C  ASN      3.0     4.6    +      -       -      +
     17C  ARG*     1.3    96.7    -      -       +      +
     19C  ALA*     1.3    63.2    +      -       -      +
     20C  SER      3.3     2.9    +      -       -      -
     21C  ALA*     3.5    10.9    +      -       +      +
     22C  LEU*     3.1    23.9    +      -       -      +
    400C  VAL*     4.0    20.0    -      -       +      -
    401C  ASP*     3.6    30.7    +      -       -      +
    404C  ALA*     3.4    26.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 19 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     15C  ASN      2.7    15.5    +      -       -      +
     16C  ASP*     3.4    17.7    +      -       -      +
     18C  ARG*     1.3    77.8    -      -       -      +
     20C  SER*     1.3    57.8    +      -       -      +
     22C  LEU*     3.3     9.5    +      -       -      +
     23C  LYS*     2.9    31.4    +      -       -      +
    394C  ARG*     5.3     9.4    -      -       -      +
    400C  VAL*     5.6     0.9    -      -       -      -
----------------------------------------------------------
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Residues in contact with SER 20 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     16C  ASP      4.6     2.5    +      -       -      -
     17C  ARG      5.3     2.2    +      -       -      -
     18C  ARG      3.3     0.6    -      -       -      -
     19C  ALA*     1.3    80.6    -      -       -      +
     21C  ALA*     1.3    62.1    +      -       -      +
     23C  LYS*     3.4     7.8    +      -       -      +
     24C  GLU*     3.3    27.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 21 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     35B  ARG*     4.5    21.1    -      -       +      +
     18C  ARG*     3.5    12.3    +      -       +      +
     20C  SER*     1.3    76.3    -      -       -      +
     22C  LEU*     1.3    65.6    +      -       -      +
     24C  GLU*     3.2     9.0    +      -       -      +
     25C  ASP*     3.0    34.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 22 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     18C  ARG      3.1    18.2    +      -       -      +
     19C  ALA*     3.6     5.4    -      -       -      +
     21C  ALA*     1.3    75.3    -      -       -      +
     23C  LYS*     1.3    60.7    +      -       -      +
     25C  ASP*     4.6     3.8    -      -       +      +
     26C  TYR*     2.8    37.8    +      -       +      +
    387C  PRO*     3.7    34.1    -      -       +      +
    390C  ALA*     3.8    11.0    -      -       +      -
    391C  GLU*     3.5    35.0    -      -       +      +
    394C  ARG*     4.2     8.7    -      -       -      +
    400C  VAL*     4.0    32.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 23 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19C  ALA      2.9    17.6    +      -       -      +
     20C  SER*     3.5     9.0    -      -       -      +
     21C  ALA      3.3     0.2    -      -       -      -
     22C  LEU*     1.3    77.7    -      -       -      +
     24C  GLU*     1.3    64.3    +      -       -      +
     26C  TYR*     3.8     4.1    -      -       -      +
     27C  GLU*     2.8    70.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 24 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     35B  ARG*     3.8    31.0    +      -       -      +
     20C  SER*     3.3    16.7    +      -       -      +
     21C  ALA*     3.2     8.9    +      -       -      +
     22C  LEU      3.2     0.4    -      -       -      -
     23C  LYS*     1.3    85.4    +      -       -      +
     25C  ASP*     1.3    63.5    +      -       -      +
     27C  GLU*     3.8    16.3    -      -       -      +
     28C  ALA*     3.0    24.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 25 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     32B  ASN*     2.8    25.0    +      -       -      +
     35B  ARG*     2.8    28.1    +      -       -      -
     21C  ALA*     3.0    26.7    +      -       -      +
     22C  LEU*     4.0     5.7    +      -       +      +
     24C  GLU*     1.3    75.5    -      -       -      +
     26C  TYR*     1.3    57.2    +      -       -      +
     28C  ALA*     3.7     6.2    -      -       -      +
     29C  LEU*     2.9    30.5    +      -       -      +
    387C  PRO*     3.7    23.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 26 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     22C  LEU*     2.8    22.7    +      -       +      +
     23C  LYS*     3.8     5.2    -      -       -      +
     25C  ASP*     1.3    78.6    -      -       -      +
     27C  GLU*     1.3    63.7    +      -       +      +
     29C  LEU*     3.4     1.0    +      -       -      -
     30C  GLY*     2.8    25.1    +      -       -      -
     40C  ILE*     3.6    36.7    -      -       +      +
     41C  GLU*     2.8    31.2    +      -       -      -
     44C  THR*     2.8    27.0    +      -       -      +
    387C  PRO*     3.6    30.2    -      -       +      +
    388C  ILE*     4.1     3.6    -      -       -      -
    391C  GLU*     3.6    28.9    -      -       +      +
    395C  ARG*     3.9     9.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 27 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     23C  LYS*     2.8    57.1    +      -       +      +
     24C  GLU*     3.8    17.6    -      -       -      +
     26C  TYR*     1.3    80.0    -      -       +      +
     28C  ALA*     1.3    60.3    +      -       -      +
     30C  GLY*     3.3     2.6    +      -       -      +
     31C  ALA*     3.0    29.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 28 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     28B  ALA*     4.5    24.0    -      -       +      +
     35B  ARG*     6.1     1.3    -      -       -      +
     24C  GLU      3.0    18.2    +      -       -      +
     25C  ASP*     3.7     8.3    -      -       -      +
     27C  GLU*     1.3    77.3    -      -       -      +
     29C  LEU*     1.3    60.4    +      -       -      +
     31C  ALA*     3.4     5.9    +      -       -      +
     32C  ASN*     3.1    22.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 29 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     25C  ASP      2.9    18.2    +      -       -      +
     26C  TYR      3.8     3.6    -      -       -      +
     28C  ALA*     1.3    73.6    -      -       -      +
     30C  GLY*     1.3    59.7    +      -       -      +
     32C  ASN*     3.2    10.9    +      -       +      +
     33C  LEU*     2.8    40.8    +      -       +      +
     40C  ILE*     4.0     7.4    -      -       +      -
    383C  THR*     3.7    27.4    -      -       +      -
    384C  ASP      3.5    22.0    -      -       -      +
    385C  VAL*     4.2     2.7    -      -       +      -
    387C  PRO*     4.1    15.3    -      -       +      -
    388C  ILE*     3.7    33.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 30 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     26C  TYR      2.8    17.6    +      -       -      -
     27C  GLU*     3.3     3.3    +      -       -      -
     28C  ALA      3.2     0.4    -      -       -      -
     29C  LEU*     1.3    78.4    -      -       -      +
     31C  ALA*     1.3    54.9    +      -       -      +
     33C  LEU*     3.4     2.4    +      -       -      +
     34C  ALA*     3.0    28.9    +      -       -      +
     38C  VAL      4.7     0.7    -      -       -      +
     40C  ILE*     3.7    30.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 31 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24B  GLU*     4.5    14.6    -      -       -      +
     27C  GLU      3.0    16.3    +      -       -      +
     28C  ALA*     3.7     6.3    -      -       -      +
     29C  LEU      3.3     0.2    -      -       -      -
     30C  GLY*     1.3    73.2    -      -       -      +
     32C  ASN*     1.3    65.8    +      -       -      +
     34C  ALA*     3.3     8.6    +      -       -      +
     35C  ARG*     3.2    28.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 32 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     25B  ASP*     3.4    25.0    +      -       -      +
    384B  ASP*     5.7     3.2    +      -       -      -
     28C  ALA      3.1    15.2    +      -       -      +
     29C  LEU*     3.2    17.4    +      -       +      +
     31C  ALA*     1.3    77.3    -      -       -      +
     33C  LEU*     1.3    63.0    +      -       -      +
     35C  ARG*     3.2    33.8    +      -       -      +
     36C  ARG*     2.9    42.7    +      -       -      +
    383C  THR*     6.1     0.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 33 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     29C  LEU*     2.8    37.4    +      -       +      +
     30C  GLY*     3.9     3.6    -      -       -      +
     32C  ASN*     1.3    74.0    -      -       -      +
     34C  ALA*     1.3    64.6    +      -       -      +
     36C  ARG*     2.9    39.7    +      -       -      +
     38C  VAL*     2.8    44.5    +      -       +      +
     40C  ILE*     3.9    32.5    -      -       +      +
     43C  VAL*     4.9     0.2    -      -       +      -
    355C  LEU*     3.9    32.5    -      -       +      -
    388C  ILE*     4.2    11.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 34 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30C  GLY      3.0    17.6    +      -       -      +
     31C  ALA*     3.5    10.3    -      -       -      +
     32C  ASN      3.2     0.2    -      -       -      -
     33C  LEU*     1.3    76.4    -      -       -      +
     35C  ARG*     1.3    58.1    +      -       +      +
     36C  ARG      3.0     0.2    -      -       -      -
     37C  GLY*     3.0    18.9    +      -       -      -
     38C  VAL      3.4    10.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 35 (chain C). Click here for Legend to table.
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                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     21B  ALA*     3.7    28.3    +      -       -      +
     24B  GLU*     4.1    30.3    +      -       -      +
     25B  ASP*     2.7    44.5    +      -       -      -
     31C  ALA      3.2    14.8    +      -       -      +
     32C  ASN*     3.2    22.6    +      -       -      +
     33C  LEU      3.2     0.8    -      -       -      -
     34C  ALA*     1.3    76.7    -      -       +      +
     36C  ARG*     1.3    61.3    +      -       +      +
     37C  GLY      3.3     1.3    +      -       -      -
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A short description of the analytical approach
The contact analysis used in this page is based upon the approach developed in: Sobolev V., Wade R.C., Vriend G. and Edelman M. PROTEINS (1996) 25, 120-129. Contact legitimacy depends on the hydrophobic-hydrophilic properties of the contacting atoms. In order to define it, for each inter-atomic contact, eight atom classes have been introduced:


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

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

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