Contacts of the helix formed by residues 165 - 187 (chain D) 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 D).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    181C  PRO*     4.3     2.0    -      -       -      -
     96D  VAL      4.9     5.2    -      -       -      +
     97D  ALA*     6.2     0.7    -      -       +      -
    157D  ALA*     3.6    19.3    -      -       -      +
    160D  GLU      4.5     0.5    -      -       -      +
    161D  GLY*     3.7     0.7    -      -       -      -
    162D  GLN*     2.9    58.0    +      -       +      +
    163D  VAL      4.5     1.8    -      -       -      +
    164D  GLY*     1.3    79.3    -      -       -      +
    166D  ALA*     1.3    64.1    +      -       -      +
    167D  ALA      3.4     2.9    +      -       -      -
    168D  TYR*     3.4    32.8    +      -       +      -
    169D  SER*     2.9    30.1    +      -       -      +
    259D  MET*     5.9     0.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 166 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    126C  PHE*     4.2    14.4    -      -       +      -
    178C  MET*     3.8     5.7    -      -       +      +
    181C  PRO*     4.1    14.9    -      -       +      +
    182C  ILE*     3.8    28.7    -      -       +      -
    185C  ASP*     4.4     5.8    -      -       -      +
     98D  ILE      4.9     4.9    +      -       -      +
    100D  THR*     4.0    11.9    -      -       -      +
    109D  HIS*     5.3     1.6    -      -       +      -
    114D  PHE*     4.1     2.1    -      -       -      -
    164D  GLY      3.6     4.4    +      -       -      +
    165D  GLN*     1.3    74.1    -      -       -      +
    167D  ALA*     1.3    62.5    +      -       -      +
    170D  ALA*     3.0    24.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 167 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     96D  VAL*     4.4     8.5    -      -       +      -
     98D  ILE      5.7     0.2    +      -       -      -
    109D  HIS*     4.2    16.2    +      -       -      +
    114D  PHE*     3.7    34.4    -      -       +      +
    117D  VAL*     3.8    27.1    -      -       +      +
    118D  ILE*     4.1     3.4    -      -       +      +
    164D  GLY      5.3     0.8    +      -       -      -
    165D  GLN      3.4     0.8    -      -       -      -
    166D  ALA*     1.3    77.3    -      -       -      +
    168D  TYR*     1.3    63.4    +      -       -      +
    170D  ALA*     3.4     3.1    +      -       -      +
    171D  SER*     3.0    23.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with TYR 168 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     94D  ILE      3.6    25.6    -      -       -      -
     95D  ALA*     3.9    19.1    -      -       +      -
     96D  VAL*     4.8    13.1    +      -       -      +
    117D  VAL*     3.9     5.9    -      -       +      +
    121D  ASN*     3.9     5.6    -      -       -      -
    155D  SER*     3.6    23.3    -      -       -      -
    157D  ALA*     3.9     9.9    -      -       +      -
    165D  GLN*     3.4    34.2    +      -       +      +
    167D  ALA*     1.3    76.5    -      -       -      +
    169D  SER*     1.3    62.1    +      -       -      +
    171D  SER*     2.8    22.2    +      -       -      -
    172D  LYS*     3.0    26.2    +      -       +      +
    301D  NAD      2.8    49.6    +      +       -      -
----------------------------------------------------------
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Residues in contact with SER 169 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    177C  GLY*     3.5    21.7    -      -       -      -
    181C  PRO*     3.7     9.3    -      -       -      +
    157D  ALA*     2.8    35.3    +      -       -      +
    158D  ALA*     4.3     1.9    -      -       -      -
    161D  GLY*     3.3    16.5    -      -       -      -
    165D  GLN*     2.9    24.9    +      -       -      +
    166D  ALA      4.0     0.9    -      -       -      -
    168D  TYR*     1.3    74.1    -      -       -      +
    170D  ALA*     1.3    56.3    +      -       -      +
    172D  LYS*     3.8     1.2    -      -       -      +
    173D  GLY*     2.9    27.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 170 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    122C  LEU*     4.2     7.6    -      -       +      +
    174C  GLY*     3.4    29.1    -      -       -      +
    178C  MET*     4.0     9.6    -      -       +      +
    114D  PHE*     3.8    24.5    -      -       +      -
    118D  ILE*     4.0     7.0    -      -       +      -
    122D  LEU*     4.8     0.2    -      -       -      +
    166D  ALA      3.0    19.5    +      -       -      +
    167D  ALA      3.7     4.0    -      -       -      +
    169D  SER*     1.3    74.5    -      -       -      +
    171D  SER*     1.3    64.1    +      -       -      +
    174D  GLY*     3.1    19.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with SER 171 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    117D  VAL*     4.1     6.9    -      -       -      +
    118D  ILE*     3.8    19.0    -      -       -      +
    121D  ASN*     3.1    40.5    +      -       -      +
    122D  LEU*     3.9    12.0    -      -       -      +
    167D  ALA      3.0    13.7    +      -       -      -
    168D  TYR*     2.8    17.6    +      -       -      -
    170D  ALA*     1.3    79.2    -      -       -      +
    172D  LYS*     1.3    61.6    +      -       -      +
    174D  GLY*     3.4     2.3    +      -       -      -
    175D  ILE*     3.4    23.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 172 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     92D  ALA      5.4     0.8    +      -       -      -
    121D  ASN*     3.9    14.8    -      -       -      +
    153D  THR      3.1    16.0    +      -       -      -
    154D  ALA*     3.6    21.2    +      -       -      +
    155D  SER*     3.8    26.7    -      -       -      +
    158D  ALA*     3.9    11.9    -      -       +      +
    168D  TYR*     3.0    40.2    +      -       +      +
    169D  SER*     4.2     2.5    -      -       -      +
    171D  SER*     1.3    76.2    +      -       -      +
    173D  GLY*     1.3    64.4    +      -       -      +
    174D  GLY      3.2     1.1    -      -       -      -
    175D  ILE*     3.4    17.0    +      -       +      +
    176D  VAL*     3.2    26.3    +      -       -      +
    301D  NAD      3.0    42.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLY 173 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    173C  GLY*     3.3    26.7    -      -       -      +
    177C  GLY*     4.4     5.8    -      -       -      -
    158D  ALA*     3.9    14.1    -      -       -      +
    169D  SER      2.9    18.3    +      -       -      -
    170D  ALA      4.0     0.2    -      -       -      -
    172D  LYS*     1.3    77.4    -      -       -      +
    174D  GLY*     1.3    56.4    +      -       -      +
    175D  ILE      3.3     0.2    -      -       -      -
    176D  VAL*     3.7     5.1    -      -       -      +
    177D  GLY      3.0    22.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLY 174 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    170C  ALA*     3.4    29.4    -      -       -      -
    173C  GLY      4.2     0.2    -      -       -      -
    174C  GLY      3.7     2.6    -      -       -      +
    122D  LEU*     3.6    17.3    -      -       -      -
    170D  ALA      3.1    12.8    +      -       -      -
    171D  SER      3.4     4.9    +      -       -      -
    172D  LYS      3.2     0.6    -      -       -      -
    173D  GLY*     1.3    73.5    -      -       -      +
    175D  ILE*     1.3    61.8    +      -       -      +
    177D  GLY      3.4     0.7    +      -       -      -
    178D  MET*     3.1    24.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 175 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    121D  ASN      3.7    22.9    -      -       -      +
    122D  LEU*     4.0    11.7    -      -       +      -
    125D  THR*     4.6    10.5    -      -       +      +
    152D  ASN*     3.9    30.7    -      -       +      +
    153D  THR      3.8    19.5    -      -       -      +
    154D  ALA*     4.3     4.0    -      -       +      -
    171D  SER      3.4    15.3    +      -       -      +
    172D  LYS*     3.4    23.2    +      -       +      +
    173D  GLY      3.3     0.8    -      -       -      -
    174D  GLY*     1.3    73.7    -      -       -      +
    176D  VAL*     1.3    63.4    +      -       -      +
    178D  MET*     3.4    18.1    +      -       +      +
    179D  THR*     2.9    26.0    +      -       -      +
    195D  THR*     4.1    13.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 176 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    158C  ALA      5.1     3.3    -      -       -      +
    154D  ALA*     4.0    15.0    -      -       +      -
    158D  ALA*     4.0    17.5    -      -       +      -
    159D  PHE*     4.2    26.5    -      -       +      -
    172D  LYS      3.2    14.7    +      -       -      +
    173D  GLY*     3.7     9.9    -      -       -      +
    175D  ILE*     1.3    77.8    -      -       -      +
    177D  GLY*     1.3    63.6    +      -       -      +
    179D  THR*     3.3    18.6    +      -       -      -
    180D  LEU      4.6     1.4    +      -       -      -
    195D  THR*     4.9     0.9    -      -       +      -
    250D  VAL*     4.2    23.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 177 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    157C  ALA      4.3     3.8    -      -       -      +
    158C  ALA      3.7    21.0    -      -       -      +
    159C  PHE      6.0     0.3    -      -       -      -
    161C  GLY      5.2     0.5    +      -       -      -
    169C  SER*     3.4    30.4    -      -       -      -
    173C  GLY*     4.4     3.4    -      -       -      -
    173D  GLY      3.0    15.3    +      -       -      -
    174D  GLY      3.8     3.8    -      -       -      -
    176D  VAL*     1.3    79.2    -      -       -      +
    178D  MET*     1.3    58.7    +      -       -      +
    179D  THR      3.7     0.2    +      -       -      -
    180D  LEU*     4.5     0.7    +      -       -      +
    181D  PRO*     3.5     9.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with MET 178 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    114C  PHE*     4.0    25.1    -      -       -      -
    166C  ALA      3.8    17.7    -      -       -      +
    169C  SER*     4.4     0.9    -      -       -      -
    170C  ALA*     4.1     8.5    -      -       +      +
    122D  LEU*     4.2    16.4    -      -       +      -
    125D  THR*     4.0    26.5    -      -       +      -
    126D  PHE*     4.2    16.2    -      -       +      +
    129D  ILE*     4.2    15.3    -      -       +      -
    152D  ASN*     5.7     1.8    -      -       -      +
    174D  GLY      3.1    14.9    +      -       -      +
    175D  ILE*     3.7    13.9    -      -       +      +
    176D  VAL      3.3     0.2    -      -       -      -
    177D  GLY*     1.3    75.8    -      -       -      +
    179D  THR*     1.3    64.4    +      -       -      +
    180D  LEU      3.5     1.1    -      -       -      -
    181D  PRO*     3.4     8.5    -      -       +      +
    182D  ILE*     3.2    42.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with THR 179 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    152D  ASN*     4.4     3.4    +      -       -      +
    175D  ILE      2.9    18.4    +      -       -      -
    176D  VAL*     3.3    12.9    +      -       -      -
    178D  MET*     1.3    77.1    -      -       -      +
    180D  LEU*     1.3    63.9    +      -       -      +
    182D  ILE*     3.9     2.1    -      -       -      +
    183D  ALA*     3.1    22.4    +      -       -      +
    193D  VAL*     4.0    26.8    -      -       +      +
    195D  THR*     2.8    33.0    +      -       -      +
    248D  GLY      4.0    10.3    -      -       -      +
    249D  GLU      4.0    21.1    -      -       -      +
    250D  VAL*     4.7     3.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 180 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    256B  ALA*     3.9    31.6    -      -       +      +
    258B  ARG*     3.7    45.8    -      -       +      +
    159C  PHE      4.0    19.1    -      -       -      +
    160C  GLU*     4.1     7.4    -      -       -      -
    161C  GLY      4.3     2.0    -      -       -      +
    176D  VAL      4.6     1.2    +      -       -      -
    177D  GLY      4.5     1.2    +      -       -      +
    179D  THR*     1.3    79.4    -      -       -      +
    181D  PRO*     1.3    70.9    -      -       +      +
    183D  ALA*     3.2     4.6    +      -       -      +
    184D  ARG*     2.9    49.4    +      -       +      +
    248D  GLY*     4.1    13.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with PRO 181 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    161C  GLY*     3.6    22.0    -      -       -      +
    162C  GLN      3.5    21.9    -      -       -      +
    165C  GLN      4.3     0.9    -      -       -      -
    166C  ALA*     4.2    16.4    -      -       -      +
    169C  SER*     3.8    16.6    -      -       -      +
    177D  GLY      3.5    19.5    -      -       -      +
    178D  MET*     3.4    17.3    -      -       -      +
    180D  LEU*     1.3    94.2    -      -       +      +
    182D  ILE*     1.3    55.7    +      -       -      +
    184D  ARG*     3.5     4.4    +      -       +      +
    185D  ASP*     2.9    34.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 182 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    100C  THR*     3.7    16.8    -      -       -      +
    166C  ALA*     3.8    10.3    -      -       +      -
    126D  PHE*     4.0    20.2    -      -       +      -
    129D  ILE*     4.1    27.6    -      -       +      -
    152D  ASN*     6.3     0.2    -      -       -      +
    178D  MET*     3.2    47.8    +      -       +      +
    179D  THR*     4.0     2.9    -      -       -      +
    181D  PRO*     1.3    73.3    -      -       -      +
    183D  ALA*     1.3    63.4    +      -       -      +
    185D  ASP*     3.2     6.0    +      -       -      +
    186D  LEU*     3.0    36.2    +      -       +      +
    193D  VAL*     3.9    22.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 183 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    222B  PRO*     5.3     1.0    -      -       -      +
    256B  ALA*     4.6     7.0    -      -       +      -
    179D  THR      3.1    14.8    +      -       -      +
    180D  LEU*     3.6     7.4    -      -       +      +
    182D  ILE*     1.3    75.7    -      -       -      +
    184D  ARG*     1.3    60.9    +      -       -      +
    186D  LEU*     3.4     2.1    +      -       -      +
    187D  ALA*     3.1    24.8    +      -       -      +
    191D  ILE      4.7     3.8    -      -       -      +
    193D  VAL*     4.0    15.6    -      -       +      +
    247D  ASN*     3.5    30.3    +      -       -      +
    248D  GLY*     3.9    15.9    -      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 184 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    222B  PRO*     4.8    13.4    -      -       +      +
    256B  ALA*     4.9     3.2    +      -       +      -
    258B  ARG*     3.9    26.5    +      -       -      +
    160C  GLU*     3.4    16.4    +      -       -      +
    161C  GLY      2.8    37.8    +      -       -      -
    162C  GLN*     3.9     2.0    -      -       -      +
    163C  VAL*     3.8    23.7    -      -       +      +
    259C  MET      3.0    24.0    +      -       -      -
    260C  GLN*     3.8    10.1    +      -       -      +
    261C  PRO*     3.4    40.1    -      -       +      +
    180D  LEU*     2.9    39.3    +      -       +      +
    181D  PRO*     3.8     4.5    -      -       +      +
    183D  ALA*     1.3    75.4    -      -       +      +
    185D  ASP*     1.3    62.6    +      -       -      +
    187D  ALA*     3.5    15.9    +      -       -      +
    188D  PRO*     3.8     4.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 185 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     98C  ILE      4.7     0.2    -      -       -      +
     99C  LYS*     3.8    13.1    -      -       +      +
    100C  THR*     2.7    48.1    +      -       -      +
    101C  TYR      4.6     7.9    -      -       -      +
    163C  VAL*     3.4    13.1    -      -       -      +
    164C  GLY*     2.9    28.3    +      -       -      -
    166C  ALA*     4.4     8.0    +      -       -      +
    181D  PRO      2.9    21.0    +      -       -      +
    182D  ILE*     3.5     8.4    -      -       -      +
    184D  ARG*     1.3    75.8    -      -       -      +
    186D  LEU*     1.3    63.0    +      -       +      +
    188D  PRO*     3.4    16.1    -      -       -      +
    189D  ILE*     5.6     0.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 186 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    100C  THR*     4.4    13.5    -      -       +      -
    101C  TYR*     4.3    18.6    -      -       +      +
    129D  ILE*     5.0     0.7    -      -       +      -
    133D  ALA*     4.2    23.1    -      -       +      -
    150D  ILE*     4.3    10.5    -      -       +      -
    182D  ILE*     3.0    34.4    +      -       +      +
    183D  ALA      3.4     1.5    +      -       -      +
    185D  ASP*     1.3    79.9    -      -       +      +
    187D  ALA*     1.3    64.4    +      -       -      +
    188D  PRO*     3.4     1.8    -      -       -      -
    189D  ILE*     3.1    27.9    +      -       +      +
    190D  GLY      3.4     7.8    +      -       -      -
    191D  ILE*     3.5    45.7    +      -       +      +
    193D  VAL*     4.1     6.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 187 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    222B  PRO*     3.5    37.7    -      -       +      +
    223B  PHE*     3.9    20.2    -      -       +      +
    183D  ALA      3.1    15.2    +      -       -      +
    184D  ARG      3.7     7.0    -      -       -      +
    185D  ASP      3.4     0.2    -      -       -      -
    186D  LEU*     1.3    76.5    -      -       -      +
    188D  PRO*     1.3    69.0    -      -       +      +
    190D  GLY*     3.1    13.9    +      -       -      +
    191D  ILE      5.0     2.0    -      -       -      -
    247D  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