Contacts of the helix formed by residues 136 - 160 (chain A) in PDB entry 1O9I


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 ASN 136 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    134A  SER*     3.0    11.7    +      -       -      +
    135A  GLY*     1.3    74.9    -      -       -      +
    137A  LEU*     1.3    60.6    +      -       -      +
    138A  VAL*     2.9    21.6    +      -       -      +
    139A  ALA*     2.9    17.3    +      -       +      +
    140A  ASP*     2.9    29.1    +      -       -      -
    200A  VAL*     4.2     9.2    -      -       -      +
    201A  PRO*     4.2    15.2    -      -       -      +
    261C  LEU      5.6     0.7    -      -       -      +
    262C  HIS*     2.9    25.4    +      -       -      +
    263C  ASN*     5.3     0.4    -      -       -      +
    264C  HIS*     3.8    25.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 137 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     45A  GLN*     4.3    12.1    -      -       +      +
     49A  SER*     4.2    12.8    -      -       -      +
     55A  TYR*     4.2    21.1    -      -       +      -
     59A  LEU*     4.0    25.1    -      -       +      -
    135A  GLY*     5.4     2.0    -      -       -      -
    136A  ASN*     1.3    71.7    -      -       -      +
    138A  VAL*     1.3    61.0    +      -       -      +
    139A  ALA      3.3     0.4    -      -       -      -
    140A  ASP*     3.6    20.6    -      -       +      +
    141A  MET*     2.8    37.5    +      -       +      +
    192A  LEU*     3.6    14.7    -      -       +      +
    264C  HIS      2.8    14.1    +      -       -      +
    265C  GLN*     3.8    36.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 138 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    136A  ASN*     2.9    10.3    +      -       -      +
    137A  LEU*     1.3    78.2    -      -       -      +
    139A  ALA*     1.3    63.8    +      -       -      +
    141A  MET*     4.2     1.8    -      -       -      +
    142A  ARG*     3.2    27.7    +      -       -      +
    189A  GLN*     4.6     3.0    -      -       +      +
    192A  LEU*     3.9    24.0    -      -       +      +
    193A  GLU*     3.9    30.3    -      -       +      +
    196A  TYR*     3.9    28.3    -      -       +      -
    197A  GLY      4.3     6.1    -      -       -      +
    200A  VAL*     3.4    23.3    -      -       +      -
    264C  HIS*     3.8     8.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 139 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    134A  SER*     4.3     5.2    -      -       -      +
    136A  ASN*     2.9    21.3    +      -       +      +
    138A  VAL*     1.3    77.6    -      -       -      +
    140A  ASP*     1.3    63.5    +      -       -      +
    142A  ARG*     3.2    11.5    +      -       -      +
    143A  PHE*     3.0    23.9    +      -       -      +
    200A  VAL*     4.0    22.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASP 140 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     45A  GLN*     3.7    23.8    -      -       -      +
    132A  THR*     3.6    16.3    -      -       -      +
    133A  SER*     3.4     7.6    +      -       -      -
    134A  SER*     2.7    45.8    +      -       -      -
    135A  GLY      3.9     3.5    +      -       -      -
    136A  ASN      2.9    19.4    +      -       -      +
    137A  LEU*     3.5    11.2    +      -       +      +
    138A  VAL      3.4     0.4    -      -       -      -
    139A  ALA*     1.3    77.6    -      -       -      +
    141A  MET*     1.3    59.8    +      -       -      +
    143A  PHE*     3.1     7.0    +      -       -      +
    144A  ASN*     2.8    35.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with MET 141 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     55A  TYR*     4.0    23.6    -      -       +      -
     58A  LEU*     4.4     8.5    -      -       +      -
     59A  LEU*     3.9    27.1    -      -       +      -
    137A  LEU*     2.8    28.8    +      -       +      +
    138A  VAL      4.2     0.7    -      -       -      +
    140A  ASP*     1.3    72.9    -      -       -      +
    142A  ARG*     1.3    65.1    +      -       -      +
    144A  ASN*     3.2    10.1    +      -       -      +
    145A  VAL*     3.0    29.0    +      -       -      +
    185A  PHE*     3.5    28.1    -      -       -      +
    188A  ALA*     3.9    21.8    -      -       +      -
    189A  GLN*     4.0    23.3    -      -       +      +
    192A  LEU*     3.8    13.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 142 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    138A  VAL*     3.2    18.7    +      -       -      +
    139A  ALA*     3.2    11.1    +      -       -      +
    141A  MET*     1.3    76.2    -      -       -      +
    143A  PHE*     1.3    64.4    +      -       -      +
    145A  VAL*     3.2     5.5    +      -       -      +
    146A  VAL*     3.0    26.5    +      -       +      +
    189A  GLN*     3.6    26.5    -      -       -      +
    193A  GLU*     2.8    34.1    +      -       -      +
    198A  ILE*     2.7    35.0    +      -       -      +
    199A  ILE*     5.1     0.2    -      -       -      +
    200A  VAL*     3.5    27.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 143 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     33A  TRP*     3.7    35.2    -      +       -      -
     37A  THR*     4.7     0.2    -      -       +      -
     41A  SER*     3.6    25.6    -      -       -      -
     45A  GLN*     3.9     7.4    -      -       -      -
    130A  TYR      3.8    19.5    -      -       -      -
    132A  THR*     3.7    34.8    -      -       +      -
    139A  ALA      3.0    13.5    +      -       -      +
    140A  ASP*     3.1    10.5    +      -       -      +
    142A  ARG*     1.3    76.8    -      -       -      +
    144A  ASN*     1.3    71.0    +      -       -      +
    146A  VAL*     3.1    10.6    +      -       +      +
    147A  ARG*     2.8    36.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 144 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     42A  PHE*     3.2    22.6    -      -       +      -
     45A  GLN*     2.8    42.4    +      -       -      -
     59A  LEU*     3.4    19.0    -      -       -      +
    140A  ASP      2.8    15.9    +      -       -      +
    141A  MET*     3.2    17.2    +      -       -      +
    143A  PHE*     1.3    79.2    -      -       -      +
    145A  VAL*     1.3    66.3    +      -       -      +
    147A  ARG*     3.2     3.1    +      -       -      +
    148A  GLU*     3.1    27.7    +      -       -      +
    185A  PHE*     3.6    23.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 145 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    141A  MET      3.0    18.6    +      -       -      +
    142A  ARG*     3.2     7.6    +      -       -      +
    144A  ASN*     1.3    76.4    -      -       -      +
    146A  VAL*     1.3    55.2    +      -       +      +
    148A  GLU*     3.3     5.5    +      -       -      +
    149A  SER*     2.7    45.7    +      -       -      +
    182A  GLN*     4.0     6.5    -      -       +      +
    185A  PHE*     3.6    20.9    -      -       +      -
    186A  MET*     3.6    39.9    -      -       +      +
    189A  GLN*     3.7    17.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 146 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     33A  TRP*     3.6    26.9    -      -       +      -
    142A  ARG*     3.0    16.5    +      -       +      +
    143A  PHE*     3.1    11.9    +      -       +      +
    145A  VAL*     1.3    74.6    -      -       +      +
    147A  ARG*     1.3    67.1    +      -       -      +
    149A  SER*     3.1     6.1    +      -       -      -
    150A  GLU*     2.8    38.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 147 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     33A  TRP*     2.9    62.6    +      -       +      +
     34A  GLY      3.0    13.6    +      -       -      -
     35A  GLU*     3.0    22.8    +      -       -      -
     37A  THR*     4.1    12.1    -      -       +      -
     38A  GLY*     3.7    18.3    -      -       -      +
     42A  PHE*     4.2     6.4    -      -       +      -
     66A  GLU*     3.2    26.1    +      -       -      -
    143A  PHE*     2.8    26.1    +      -       +      +
    144A  ASN*     3.2    11.6    +      -       -      +
    146A  VAL*     1.3    72.9    -      -       -      +
    148A  GLU*     1.3    87.4    +      -       -      +
    150A  GLU*     3.9     0.9    -      -       -      +
    151A  ALA*     2.9    43.0    +      -       -      +
    178A  GLU*     5.6     1.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 148 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     42A  PHE*     3.3    13.0    -      -       +      -
     66A  GLU*     2.9    22.7    -      -       -      +
    144A  ASN      3.1    17.2    +      -       -      +
    145A  VAL      3.8     1.1    -      -       -      +
    147A  ARG*     1.3    90.5    +      -       -      +
    149A  SER*     1.3    58.5    +      -       -      +
    151A  ALA*     4.0     3.2    -      -       -      +
    152A  ARG*     3.0    23.2    +      -       -      +
    178A  GLU*     3.4    27.9    -      -       -      +
    181A  HIS*     3.3    32.5    +      -       +      +
    182A  GLN*     3.2    32.2    +      -       +      +
    185A  PHE*     4.0     9.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 149 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    145A  VAL*     2.7    32.2    +      -       -      +
    146A  VAL*     3.6     7.2    -      -       -      -
    148A  GLU*     1.3    75.9    -      -       -      +
    150A  GLU*     1.3    62.9    +      -       -      +
    152A  ARG*     3.4     1.0    +      -       -      +
    153A  LEU*     2.9    28.8    +      -       -      +
    182A  GLN*     3.5    23.6    +      -       -      +
    186A  MET*     5.6     0.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 150 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     33A  TRP*     3.5    45.9    +      -       +      +
    146A  VAL*     2.8    32.2    +      -       +      +
    149A  SER*     1.3    74.7    -      -       -      +
    151A  ALA*     1.3    63.3    +      -       -      +
    153A  LEU*     3.4    20.7    +      -       -      +
    154A  GLN*     3.0    31.6    +      -       -      +
    111D  VAL      5.6     1.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 151 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     33A  TRP*     3.6     9.8    -      -       -      +
     34A  GLY*     5.5     0.2    -      -       -      -
     35A  GLU*     4.5     2.0    -      -       -      +
    147A  ARG*     2.9    45.7    +      -       -      +
    148A  GLU*     4.0     4.0    -      -       -      +
    150A  GLU*     1.3    76.9    -      -       -      +
    152A  ARG*     1.3    57.1    +      -       -      +
    154A  GLN*     3.0    10.1    +      -       -      +
    155A  VAL*     2.9    30.7    +      -       +      +
    178A  GLU*     3.8    16.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 152 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    148A  GLU      3.0    20.2    +      -       -      +
    149A  SER      4.0     0.9    -      -       -      +
    150A  GLU      3.4     0.2    -      -       -      -
    151A  ALA*     1.3    72.3    -      -       -      +
    153A  LEU*     1.3    60.7    +      -       -      +
    155A  VAL*     4.3     0.2    -      -       -      -
    156A  SER*     2.8    42.3    +      -       -      -
    175A  LEU*     2.9    45.6    +      -       +      +
    178A  GLU*     3.1    26.8    +      -       +      +
    179A  THR*     3.1    21.6    +      -       -      +
    182A  GLN*     3.6    21.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 153 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    149A  SER      2.9    18.5    +      -       -      +
    150A  GLU*     3.5    23.6    -      -       -      +
    151A  ALA      3.2     0.2    -      -       -      -
    152A  ARG*     1.3    76.9    -      -       -      +
    154A  GLN*     1.3    59.5    +      -       +      +
    156A  SER*     3.3     9.7    +      -       -      -
    157A  ARG*     3.0    73.7    +      -       +      +
    111D  VAL      5.3     1.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 154 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27A  GLU*     3.5    31.4    +      -       +      +
     28A  SER*     5.1     4.4    +      -       -      +
     32A  GLN*     5.3     0.4    +      -       -      +
     33A  TRP*     4.2    35.7    -      -       -      +
     34A  GLY*     5.3     1.0    -      -       -      -
    150A  GLU*     3.0    20.2    +      -       -      +
    151A  ALA*     3.0     9.1    +      -       -      +
    153A  LEU*     1.3    79.2    -      -       +      +
    155A  VAL*     1.3    58.0    +      -       +      +
    157A  ARG*     3.1     6.3    +      -       -      +
    158A  LEU*     2.8    36.5    +      -       +      +
    110D  LEU*     3.6    27.4    -      -       +      +
    111D  VAL*     4.0    27.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 155 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     28A  SER*     4.7    14.1    -      -       -      +
     35A  GLU*     6.0     0.9    -      -       -      +
    151A  ALA*     2.9    20.7    +      -       +      +
    152A  ARG      3.8     1.6    -      -       -      +
    153A  LEU      3.3     0.2    -      -       -      -
    154A  GLN*     1.3    75.7    -      -       +      +
    156A  SER*     1.3    57.5    +      -       -      +
    158A  LEU*     3.2    10.7    +      -       +      +
    159A  TYR*     2.9    27.4    +      -       -      +
    171A  LEU*     3.7    35.4    -      -       +      +
    174A  LEU*     4.5    10.5    -      -       +      -
    175A  LEU*     3.5    22.0    -      -       +      +
    178A  GLU*     3.5    26.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with SER 156 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    152A  ARG*     2.8    33.6    +      -       -      +
    153A  LEU*     3.5    11.1    -      -       -      -
    155A  VAL*     1.3    76.4    -      -       -      +
    157A  ARG*     1.3    62.4    +      -       -      +
    159A  TYR*     3.3    20.0    +      -       -      +
    160A  SER*     3.6     8.3    +      -       -      -
    175A  LEU*     3.4    18.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 157 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    153A  LEU*     3.0    55.0    +      -       +      +
    154A  GLN*     3.1     7.7    +      -       -      +
    156A  SER*     1.3    77.4    -      -       -      +
    158A  LEU*     1.3    62.1    +      -       -      +
    160A  SER*     2.9    18.2    +      -       -      -
    161A  MET*     3.2    25.7    +      -       +      +
     86D  PHE*     5.6     2.4    -      -       +      -
    109D  SER      3.7     9.3    +      -       -      -
    110D  LEU*     3.0    35.5    +      -       +      -
    111D  VAL      3.2    23.2    +      -       -      -
    112D  HIS      4.2     1.2    -      -       -      -
    113D  GLY*     3.5    24.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 158 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     21A  MET*     3.6    24.4    -      -       +      +
     24A  ARG*     3.7    33.4    -      -       +      +
     25A  LEU*     3.9    14.6    -      -       +      +
     27A  GLU*     5.9     0.2    -      -       +      -
     28A  SER*     3.5    25.1    -      -       -      +
    154A  GLN*     2.8    22.1    +      -       +      +
    155A  VAL*     3.2    15.9    +      -       +      +
    157A  ARG*     1.3    75.7    -      -       -      +
    159A  TYR*     1.3    57.7    +      -       -      +
    161A  MET*     2.9    27.7    +      -       -      +
    162A  THR*     3.5     6.4    +      -       -      +
    171A  LEU*     3.8    12.3    -      -       +      -
    110D  LEU*     3.8    21.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 159 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    155A  VAL      2.9    12.9    +      -       -      +
    156A  SER*     3.3    15.0    -      -       -      +
    157A  ARG      3.1     0.4    -      -       -      -
    158A  LEU*     1.3    76.4    -      -       -      +
    160A  SER*     1.3    63.7    +      -       -      +
    162A  THR*     3.1     7.7    +      -       -      +
    165A  GLU*     5.4     1.0    +      -       -      -
    168A  ARG*     2.9    90.7    +      -       +      +
    171A  LEU*     3.7    16.4    -      -       +      +
    172A  LYS*     3.7    35.2    +      -       +      -
    175A  LEU*     5.1    10.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 160 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    156A  SER      3.6     6.6    +      -       -      -
    157A  ARG*     2.9    12.9    +      -       -      -
    159A  TYR*     1.3    82.9    -      -       -      +
    161A  MET*     1.3    58.3    +      -       -      +
    162A  THR      3.5     2.5    -      -       -      -
    168A  ARG*     4.4     6.1    +      -       -      +
     86D  PHE*     4.6    15.4    -      -       -      -
     87D  GLY*     3.7     7.4    -      -       -      -
     88D  PRO*     3.4    14.2    -      -       -      +
     89D  GLU      5.3     0.9    +      -       -      -
----------------------------------------------------------
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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