Contacts of the helix formed by residues 165 - 187 (chain C) in PDB entry 1E3S


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 GLN 165 (chain C).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     96C  VAL      5.0     5.2    -      -       -      +
     97C  ALA*     6.1     1.1    -      -       +      -
    157C  ALA*     3.7    13.6    -      -       -      +
    160C  GLU      4.5     0.5    -      -       -      +
    161C  GLY*     3.6     6.2    -      -       -      -
    162C  GLN*     2.9    57.0    +      -       +      +
    163C  VAL      4.5     1.8    -      -       -      +
    164C  GLY*     1.3    79.6    -      -       -      +
    166C  ALA*     1.3    63.6    +      -       -      +
    167C  ALA      3.3     2.9    +      -       -      -
    168C  TYR*     3.4    31.9    +      -       +      -
    169C  SER*     2.8    31.8    +      -       -      +
    259C  MET*     6.0     0.5    -      -       -      +
    181D  PRO*     4.3     2.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 166 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     98C  ILE      4.9     5.1    +      -       -      +
    100C  THR*     3.9    12.6    -      -       -      +
    109C  HIS*     5.4     1.8    -      -       +      -
    114C  PHE*     4.0     2.8    -      -       -      -
    164C  GLY      3.5     4.2    +      -       -      +
    165C  GLN*     1.3    76.4    -      -       -      +
    167C  ALA*     1.3    62.3    +      -       -      +
    170C  ALA*     3.2    24.6    +      -       -      +
    126D  PHE*     4.2    14.6    -      -       +      -
    178D  MET*     3.8     5.9    -      -       +      +
    181D  PRO*     4.2    14.7    -      -       +      +
    182D  ILE*     3.8    28.7    -      -       +      -
    185D  ASP*     4.4     5.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 167 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     96C  VAL*     4.5     8.0    -      -       +      +
    109C  HIS*     4.2    14.4    +      -       -      +
    114C  PHE*     3.6    41.8    -      -       +      +
    117C  VAL*     3.9    21.1    -      -       +      +
    118C  ILE*     4.1     2.6    -      -       -      +
    164C  GLY      5.2     1.0    +      -       -      -
    165C  GLN      3.3     1.0    -      -       -      -
    166C  ALA*     1.3    75.5    -      -       -      +
    168C  TYR*     1.3    67.5    +      -       -      +
    170C  ALA*     3.6     2.8    -      -       -      +
    171C  SER*     3.1    22.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with TYR 168 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     94C  ILE      3.5    26.9    -      -       -      -
     95C  ALA*     3.8    20.0    -      -       +      -
     96C  VAL*     4.8    13.9    +      -       -      +
    117C  VAL*     4.0     6.8    -      -       +      +
    121C  ASN*     3.8     6.3    -      -       -      -
    155C  SER*     3.7    22.9    -      -       -      -
    157C  ALA*     3.9    10.1    -      -       +      -
    165C  GLN*     3.4    33.9    +      -       +      +
    167C  ALA*     1.3    77.9    -      -       -      +
    169C  SER*     1.3    60.6    +      -       -      +
    171C  SER*     2.8    23.0    +      -       -      -
    172C  LYS*     3.0    26.3    +      -       +      +
    301C  NAD      2.8    51.2    +      +       -      -
----------------------------------------------------------
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Residues in contact with SER 169 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    157C  ALA*     2.7    36.6    +      -       -      +
    158C  ALA*     4.4     1.4    -      -       -      -
    161C  GLY*     3.3    16.5    -      -       -      -
    165C  GLN*     2.8    24.9    +      -       -      +
    166C  ALA      4.1     1.3    -      -       -      -
    168C  TYR*     1.3    69.7    -      -       -      +
    170C  ALA*     1.3    59.7    +      -       -      +
    172C  LYS*     3.8     1.6    -      -       -      +
    173C  GLY*     2.9    28.6    +      -       -      -
    177D  GLY*     3.4    22.9    -      -       -      -
    181D  PRO*     3.8     8.5    -      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 170 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    114C  PHE*     3.9    23.1    -      -       +      -
    118C  ILE*     4.0     7.6    -      -       +      -
    122C  LEU*     4.8     0.2    -      -       -      +
    166C  ALA      3.2    17.6    +      -       -      +
    167C  ALA      3.6     4.3    -      -       -      +
    169C  SER*     1.3    77.1    -      -       -      +
    171C  SER*     1.3    63.7    +      -       -      +
    174C  GLY*     3.0    19.6    +      -       -      -
    122D  LEU*     4.3     7.5    -      -       +      +
    174D  GLY*     3.4    28.6    -      -       -      +
    178D  MET*     4.1     8.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with SER 171 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    117C  VAL*     4.1     7.2    -      -       -      -
    118C  ILE*     3.8    17.4    -      -       -      +
    121C  ASN*     3.1    41.4    +      -       -      +
    122C  LEU*     3.9    11.5    -      -       -      +
    167C  ALA      3.1    13.5    +      -       -      -
    168C  TYR*     2.8    18.4    +      -       -      -
    170C  ALA*     1.3    78.6    -      -       -      +
    172C  LYS*     1.3    62.6    +      -       -      +
    174C  GLY*     3.4     2.3    +      -       -      -
    175C  ILE*     3.3    23.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 172 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     92C  ALA      5.4     0.8    +      -       -      -
     93C  GLY*     5.4     0.2    -      -       -      -
    121C  ASN*     3.8    14.4    +      -       -      +
    153C  THR      3.0    21.0    +      -       -      -
    154C  ALA*     3.6    18.3    +      -       -      +
    155C  SER*     3.8    27.6    -      -       -      +
    158C  ALA*     3.9    11.9    -      -       +      +
    168C  TYR*     3.0    38.8    +      -       +      +
    169C  SER*     4.2     2.2    -      -       -      +
    171C  SER*     1.3    81.9    +      -       -      +
    173C  GLY*     1.3    60.3    +      -       -      +
    175C  ILE*     3.3    17.5    +      -       +      +
    176C  VAL*     3.1    29.6    +      -       -      +
    301C  NAD      3.0    39.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLY 173 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    158C  ALA*     3.9    14.3    -      -       -      +
    169C  SER      2.9    17.4    +      -       -      -
    170C  ALA      4.0     0.4    -      -       -      -
    172C  LYS*     1.3    76.0    -      -       -      +
    174C  GLY*     1.3    58.7    +      -       -      +
    176C  VAL*     3.7     4.6    -      -       -      +
    177C  GLY      3.0    22.9    +      -       -      -
    173D  GLY*     3.3    26.4    -      -       -      +
    177D  GLY*     4.4     5.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLY 174 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    122C  LEU*     3.6    15.7    -      -       -      -
    170C  ALA      3.0    14.8    +      -       -      -
    171C  SER      3.4     4.7    +      -       -      -
    172C  LYS      3.2     0.2    -      -       -      -
    173C  GLY*     1.3    75.5    -      -       -      +
    175C  ILE*     1.3    64.2    +      -       -      +
    177C  GLY      3.5     0.5    +      -       -      -
    178C  MET*     3.1    24.9    +      -       -      +
    170D  ALA*     3.4    29.9    -      -       -      -
    174D  GLY      3.7     1.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 175 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    121C  ASN      3.6    22.7    -      -       -      +
    122C  LEU*     4.1    11.2    -      -       +      -
    125C  THR*     4.5     8.7    -      -       +      +
    152C  ASN*     3.9    30.3    -      -       +      +
    153C  THR      3.8    20.2    -      -       -      +
    154C  ALA*     4.4     4.0    -      -       +      -
    171C  SER      3.3    15.7    +      -       -      +
    172C  LYS*     3.3    23.1    +      -       +      +
    174C  GLY*     1.3    75.5    -      -       -      +
    176C  VAL*     1.3    62.2    +      -       -      +
    178C  MET*     3.3    20.2    +      -       +      +
    179C  THR*     3.0    23.8    +      -       -      +
    195C  THR*     4.2    13.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 176 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    154C  ALA*     4.1    14.1    -      -       +      -
    158C  ALA*     3.9    17.9    -      -       +      -
    159C  PHE*     4.1    26.5    -      -       +      -
    172C  LYS      3.1    14.6    +      -       -      +
    173C  GLY*     3.7     9.6    -      -       -      +
    174C  GLY      3.4     0.2    -      -       -      -
    175C  ILE*     1.3    76.8    -      -       -      +
    177C  GLY*     1.3    64.0    +      -       -      +
    179C  THR*     3.2    23.4    +      -       -      -
    180C  LEU      4.6     1.0    +      -       -      -
    195C  THR*     5.1     0.4    -      -       -      -
    250C  VAL*     4.3    24.3    -      -       +      +
    158D  ALA      5.4     3.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 177 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    173C  GLY      3.0    16.5    +      -       -      -
    174C  GLY      3.9     1.6    -      -       -      -
    175C  ILE      3.4     0.2    -      -       -      -
    176C  VAL*     1.3    77.0    -      -       -      +
    178C  MET*     1.3    58.7    +      -       -      +
    180C  LEU*     4.5     0.7    +      -       -      +
    181C  PRO*     3.5     9.9    -      -       -      +
    157D  ALA      4.1     3.8    -      -       -      +
    158D  ALA      3.6    21.7    -      -       -      +
    159D  PHE      6.0     0.3    -      -       -      -
    161D  GLY      5.2     0.2    +      -       -      -
    169D  SER*     3.5    29.5    -      -       -      -
    173D  GLY*     4.4     3.4    -      -       -      -
----------------------------------------------------------
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Residues in contact with MET 178 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    122C  LEU*     4.0    17.7    -      -       +      -
    125C  THR*     4.0    27.1    -      -       +      -
    126C  PHE*     4.2    15.3    -      -       +      +
    129C  ILE*     4.4    10.3    -      -       +      -
    152C  ASN*     5.8     2.0    -      -       -      +
    174C  GLY      3.1    14.4    +      -       -      +
    175C  ILE*     3.6    15.0    -      -       +      +
    176C  VAL      3.3     0.4    -      -       -      -
    177C  GLY*     1.3    75.8    -      -       -      +
    179C  THR*     1.3    64.5    +      -       -      +
    180C  LEU      3.4     0.9    -      -       -      -
    181C  PRO*     3.4     7.7    -      -       +      +
    182C  ILE*     3.2    45.2    +      -       +      +
    114D  PHE*     4.0    26.2    -      -       -      -
    166D  ALA      3.8    17.9    -      -       -      +
    169D  SER*     4.4     1.1    -      -       -      -
    170D  ALA*     4.0     8.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with THR 179 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    152C  ASN*     4.4     3.3    +      -       -      +
    175C  ILE      3.0    17.4    +      -       -      -
    176C  VAL*     3.2    13.7    +      -       -      -
    178C  MET*     1.3    77.1    -      -       -      +
    180C  LEU*     1.3    58.9    +      -       -      +
    182C  ILE*     4.0     2.0    -      -       -      +
    183C  ALA*     3.1    26.9    +      -       -      +
    193C  VAL*     4.1    19.3    -      -       +      +
    194C  VAL*     4.7     0.2    -      -       -      -
    195C  THR*     2.7    32.0    +      -       -      +
    248C  GLY*     3.9    18.6    -      -       -      +
    249C  GLU      3.9    21.1    -      -       -      +
    250C  VAL*     4.5     4.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 180 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    256A  ALA*     3.8    36.1    -      -       +      +
    258A  ARG*     3.8    38.6    -      -       +      +
    176C  VAL      4.6     1.2    +      -       -      -
    177C  GLY      4.5     1.2    +      -       -      +
    179C  THR*     1.3    77.4    -      -       -      +
    181C  PRO*     1.3    71.2    -      -       +      +
    183C  ALA*     3.2     4.9    +      -       +      +
    184C  ARG*     2.9    55.2    +      -       +      +
    248C  GLY*     4.3    10.1    -      -       -      +
    159D  PHE      4.1     7.0    -      -       -      +
    160D  GLU*     4.0    19.5    -      -       -      -
    161D  GLY      4.3     2.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with PRO 181 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    177C  GLY      3.5    14.8    -      -       -      +
    178C  MET*     3.4    14.1    -      -       -      +
    180C  LEU*     1.3    95.2    -      -       +      +
    182C  ILE*     1.3    54.5    +      -       -      +
    184C  ARG*     3.7     4.0    -      -       +      +
    185C  ASP*     2.8    36.8    +      -       -      +
    161D  GLY*     3.6    21.5    -      -       -      +
    162D  GLN      3.5    21.2    -      -       -      +
    165D  GLN      4.3     0.9    -      -       -      +
    166D  ALA*     4.1    17.0    -      -       -      +
    169D  SER*     3.7    22.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 182 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    126C  PHE*     4.0    18.4    -      -       +      -
    129C  ILE*     4.0    26.0    -      -       +      -
    178C  MET*     3.2    48.2    +      -       +      +
    179C  THR*     4.1     2.5    -      -       -      +
    181C  PRO*     1.3    73.4    -      -       -      +
    183C  ALA*     1.3    64.3    +      -       -      +
    185C  ASP*     3.2     4.6    +      -       -      +
    186C  LEU*     3.0    36.4    +      -       +      +
    193C  VAL*     4.0    22.2    -      -       +      -
    100D  THR*     3.6    19.3    -      -       -      +
    166D  ALA*     3.8    11.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 183 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    222A  PRO*     5.3     0.7    -      -       -      +
    256A  ALA*     4.5     7.2    -      -       +      -
    179C  THR      3.1    15.8    +      -       -      +
    180C  LEU      3.2     7.2    +      -       -      +
    182C  ILE*     1.3    77.2    -      -       -      +
    184C  ARG*     1.3    58.5    +      -       -      +
    186C  LEU      3.5     1.0    +      -       -      -
    187C  ALA*     3.2    23.7    +      -       -      +
    191C  ILE      4.7     4.1    -      -       -      +
    193C  VAL*     4.0    15.1    -      -       +      +
    247C  ASN*     3.6    30.2    +      -       -      +
    248C  GLY*     3.9    16.4    -      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 184 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    222A  PRO*     4.8    12.8    -      -       +      -
    256A  ALA*     4.9     3.0    +      -       +      -
    258A  ARG*     3.8    27.3    +      -       -      +
    180C  LEU*     2.9    37.2    +      -       +      +
    181C  PRO*     3.8     4.5    -      -       +      +
    183C  ALA*     1.3    72.8    -      -       -      +
    185C  ASP*     1.3    67.0    +      -       -      +
    186C  LEU      3.4     0.2    +      -       -      -
    187C  ALA*     3.5    17.3    +      -       -      +
    188C  PRO*     3.8     4.3    -      -       -      +
    160D  GLU*     3.3    17.2    +      -       -      +
    161D  GLY      2.9    36.7    +      -       -      -
    162D  GLN*     4.5     2.2    -      -       -      +
    163D  VAL*     3.9    22.1    -      -       +      +
    259D  MET      3.0    24.0    +      -       -      -
    260D  GLN*     3.8     9.9    +      -       -      +
    261D  PRO*     3.3    41.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASP 185 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    181C  PRO*     2.8    20.1    +      -       -      +
    182C  ILE*     3.2     6.4    +      -       -      +
    184C  ARG*     1.3    77.7    -      -       -      +
    186C  LEU*     1.3    63.3    +      -       +      +
    188C  PRO*     3.4    15.9    -      -       -      +
     98D  ILE      4.7     0.2    -      -       -      +
     99D  LYS*     3.7    14.6    -      -       +      +
    100D  THR*     2.8    46.9    +      -       -      +
    101D  TYR      4.5     7.4    -      -       -      +
    163D  VAL*     3.4    17.7    -      -       -      +
    164D  GLY      2.9    29.9    +      -       -      -
    166D  ALA*     4.4     7.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 186 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    129C  ILE*     5.0     0.9    -      -       +      -
    133C  ALA*     4.3    20.0    -      -       +      -
    150C  ILE*     4.3     6.5    -      -       +      -
    182C  ILE*     3.0    32.8    +      -       +      +
    183C  ALA      3.8     1.1    -      -       -      +
    185C  ASP*     1.3    78.8    -      -       +      +
    187C  ALA*     1.3    64.5    +      -       -      +
    188C  PRO*     3.4     2.2    -      -       -      -
    189C  ILE*     3.2    25.6    +      -       +      +
    190C  GLY      3.3     8.7    +      -       -      -
    191C  ILE*     3.5    43.8    +      -       +      +
    193C  VAL*     4.1     7.4    -      -       +      -
    100D  THR*     4.3    14.4    -      -       +      -
    101D  TYR*     4.2    28.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 187 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    222A  PRO*     3.5    37.2    -      -       +      +
    223A  PHE*     3.9    20.7    -      -       +      -
    183C  ALA      3.2    12.3    +      -       -      +
    184C  ARG      3.7     9.9    -      -       -      +
    185C  ASP      3.3     0.4    -      -       -      -
    186C  LEU*     1.3    75.2    -      -       -      +
    188C  PRO*     1.3    71.4    -      -       +      +
    190C  GLY*     3.0    14.8    +      -       -      +
    191C  ILE      5.0     2.0    -      -       -      -
    247C  ASN*     5.8     0.7    -      -       -      +
----------------------------------------------------------
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A short description of the analytical approach
The contact analysis used in this page is based upon the approach developed in: Sobolev V., Wade R.C., Vriend G. and Edelman M. PROTEINS (1996) 25, 120-129. Contact legitimacy depends on the hydrophobic-hydrophilic properties of the contacting atoms. In order to define it, for each inter-atomic contact, eight atom classes have been introduced:


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

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

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