Contacts of the helix formed by residues 127 - 152 (chain A) in PDB entry 2CHP


Residue contacts within the protein are derived with the CSU software (Sobolev V., Sorokine A., Prilusky J., Abola E.E. and Edelman M. (1999) Automated analysis of interatomic contacts in proteins. Bioinformatics, 15, 327-332). A short description of the analytical approach is given at the end of the page.
For CSU analysis of other PDB entry

Note:
Non-standard 3 letter residue codes indicate a heterogroup. To identify and analyse, use LPC software

Legend:
Dist - nearest distance (Å) between atoms of two residues
Surf - contact surface area (Å2) between two residues
HB   - hydrophilic-hydrophilic contact (hydrogen bond)
Arom - aromatic-aromatic contact
Phob - hydrophobic-hydrophobic contact
DC   - hydrophobic-hydrophilic contact (destabilizing contact)
+/-  - indicates presence/absence of a specific contacts
*    - indicates residues forming contacts  by their side chain
       (including CA atoms)
Residues in contact with ASP 127 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     10A  GLN*     5.7     0.9    -      -       -      +
     13A  VAL*     4.3     5.2    -      -       +      +
     67A  ARG*     2.9    26.9    +      -       -      -
     71A  ILE*     3.9    16.1    -      -       -      +
    122A  ALA*     2.9    27.9    +      -       +      +
    123A  GLU*     4.6     1.5    +      -       -      +
    125A  ASN*     4.2    13.7    -      -       +      +
    126A  GLN*     1.3    74.1    -      -       -      +
    128A  ASN*     1.3    63.0    +      -       -      +
    129A  ALA      3.7     1.4    +      -       -      -
    130A  THR*     2.7    32.0    +      -       -      +
    131A  ALA*     3.3    15.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 128 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    123A  GLU*     5.3    10.8    -      -       -      +
    126A  GLN*     3.6    15.2    +      -       -      +
    127A  ASP*     1.3    76.9    +      -       -      +
    129A  ALA*     1.3    59.2    +      -       -      +
    131A  ALA*     3.4     8.3    +      -       -      +
    132A  ASP*     2.8    29.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 129 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     67A  ARG*     3.6    29.8    +      -       -      +
    127A  ASP*     3.3     1.4    +      -       -      +
    128A  ASN*     1.3    79.4    -      -       -      +
    130A  THR*     1.3    61.3    +      -       -      +
    132A  ASP*     3.3     8.7    +      -       -      +
    133A  LEU*     3.1    21.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 130 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     13A  VAL*     4.3     4.0    -      -       +      -
     17A  LEU*     3.7    36.6    -      -       +      -
     67A  ARG*     2.9    29.8    +      -       +      +
     71A  ILE*     4.0     4.3    -      -       -      +
    118A  VAL*     4.6     1.6    -      -       +      -
    122A  ALA*     4.1    12.1    -      -       +      -
    127A  ASP*     2.7    34.9    +      -       -      +
    129A  ALA*     1.3    71.9    -      -       -      +
    131A  ALA*     1.3    67.3    +      -       -      +
    133A  LEU*     3.2    11.9    +      -       -      +
    134A  PHE*     3.4    20.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 131 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    118A  VAL      5.8     0.2    -      -       -      -
    119A  ILE*     3.8    20.0    -      -       +      +
    122A  ALA*     3.8    14.8    -      -       +      +
    123A  GLU*     4.1    24.2    -      -       +      +
    127A  ASP      3.3    12.9    +      -       -      +
    128A  ASN*     3.6    11.0    -      -       -      +
    130A  THR*     1.3    78.1    -      -       -      +
    132A  ASP*     1.3    61.7    +      -       -      +
    134A  PHE*     3.1     5.5    +      -       -      +
    135A  VAL*     2.9    28.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with ASP 132 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    128A  ASN      2.8    17.7    +      -       -      +
    129A  ALA*     3.6     8.6    -      -       -      +
    130A  THR      3.2     0.2    -      -       -      -
    131A  ALA*     1.3    75.3    -      -       -      +
    133A  LEU*     1.3    65.7    +      -       -      +
    135A  VAL*     3.2    10.7    +      -       -      +
    136A  GLY*     3.1    18.9    +      -       -      -
    132C  ASP*     4.2    15.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 133 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     17A  LEU*     5.7     0.2    -      -       +      -
     60A  THR*     6.1     0.2    -      -       +      -
     63A  THR*     3.5    36.3    -      -       +      +
     64A  ILE*     4.2    11.0    -      -       +      -
     67A  ARG*     3.6    34.1    -      -       +      -
    129A  ALA      3.1    12.9    +      -       -      +
    130A  THR*     3.2     9.4    +      -       -      +
    132A  ASP*     1.3    78.8    +      -       -      +
    134A  PHE*     1.3    74.2    +      -       +      +
    136A  GLY*     3.4     2.3    +      -       -      -
    137A  LEU*     3.0    41.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 134 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     17A  LEU*     3.8    35.2    -      -       +      -
     20A  GLN*     3.9    29.8    -      -       +      -
     24A  TRP*     5.5     0.7    -      -       -      -
     64A  ILE*     4.0    21.3    -      -       +      -
    115A  SER*     3.7    39.7    -      -       -      +
    118A  VAL*     3.7    15.0    -      -       +      -
    119A  ILE*     4.1     5.4    -      -       +      -
    130A  THR*     3.4    17.9    -      -       +      +
    131A  ALA*     3.1     7.1    +      -       -      +
    133A  LEU*     1.3    89.0    -      -       +      +
    135A  VAL*     1.4    64.6    +      -       -      +
    137A  LEU*     3.2    21.6    +      -       +      +
    138A  ILE*     3.0    30.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 135 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    119A  ILE*     3.7    22.6    -      -       +      +
    131A  ALA*     2.9    23.6    +      -       +      +
    132A  ASP*     3.2    13.2    +      -       -      +
    134A  PHE*     1.4    77.2    -      -       -      +
    136A  GLY*     1.3    61.8    +      -       -      +
    138A  ILE*     3.3     7.1    +      -       -      +
    139A  GLU*     3.2    24.8    +      -       -      +
    128C  ASN*     3.8    23.8    -      -       +      +
    129C  ALA*     4.0     5.6    -      -       -      +
    132C  ASP*     3.6    36.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 136 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    132A  ASP*     3.1    10.8    +      -       -      -
    133A  LEU      3.7     3.8    -      -       -      -
    135A  VAL*     1.3    78.7    -      -       -      +
    137A  LEU*     1.3    65.5    +      -       -      +
    139A  GLU*     3.4    19.6    +      -       -      +
    140A  GLU*     3.2    21.0    +      -       -      +
    132C  ASP*     5.3     1.3    -      -       -      -
----------------------------------------------------------
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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
----------------------------------------------------------
     24A  TRP*     4.3    16.4    -      -       +      +
     56A  HIS*     4.4    11.9    -      -       +      +
     60A  THR*     3.6    42.6    -      -       +      +
     63A  THR*     6.4     0.2    -      -       +      -
     64A  ILE*     4.2     6.5    -      -       +      -
    111A  ILE*     5.9     0.2    -      -       +      -
    115A  SER*     5.0     6.1    -      -       -      +
    133A  LEU*     3.0    30.6    +      -       +      +
    134A  PHE*     3.2    37.6    +      -       +      +
    136A  GLY*     1.3    77.3    -      -       -      +
    138A  ILE*     1.3    57.4    +      -       -      +
    140A  GLU*     3.2     4.7    +      -       +      +
    141A  VAL*     2.9    35.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 138 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    112A  SER*     3.8    11.0    -      -       -      +
    115A  SER*     3.8    21.5    -      -       -      -
    116A  LYS*     3.5    28.7    -      -       +      -
    119A  ILE*     3.5    32.1    -      -       +      -
    134A  PHE      3.0    11.7    +      -       -      +
    135A  VAL*     3.3     8.3    +      -       -      +
    137A  LEU*     1.3    74.0    -      -       -      +
    139A  GLU*     1.3    57.8    +      -       -      +
    141A  VAL*     4.2     7.6    -      -       -      -
    142A  GLU*     2.8    64.2    +      -       -      +
     67C  ARG*     4.9     0.4    -      -       -      +
    128C  ASN*     5.9     1.8    -      -       +      -
    129C  ALA*     3.9    16.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 139 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    135A  VAL*     3.2    14.2    +      -       -      +
    136A  GLY*     3.5    15.5    -      -       -      +
    138A  ILE*     1.3    78.1    -      -       -      +
    140A  GLU*     1.3    63.1    +      -       -      +
    142A  GLU*     4.0     1.2    -      -       -      +
    143A  LYS*     3.1    22.5    +      -       -      +
     67C  ARG*     4.5    12.6    +      -       -      +
    129C  ALA*     3.2    24.8    -      -       +      +
    132C  ASP*     2.5    42.1    -      -       -      +
    133C  LEU*     4.2     5.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 140 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     53A  LEU*     5.8     0.3    -      -       -      +
     56A  HIS*     3.5    38.8    -      -       +      +
    136A  GLY      3.2     7.2    +      -       -      +
    137A  LEU*     3.2    10.3    +      -       +      +
    139A  GLU*     1.3    81.3    -      -       -      +
    141A  VAL*     1.3    61.6    +      -       -      +
    143A  LYS*     3.3    23.3    +      -       -      +
    144A  GLN*     2.8    52.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 141 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24A  TRP*     3.8    35.9    -      -       +      -
     56A  HIS*     5.0     3.6    -      -       +      -
    108A  TYR*     3.8    42.5    -      -       +      +
    111A  ILE*     4.5     4.9    -      -       +      -
    112A  SER*     3.8    20.2    -      -       -      +
    137A  LEU*     2.9    25.0    +      -       +      +
    138A  ILE*     3.7     9.2    -      -       -      +
    140A  GLU*     1.3    72.7    -      -       -      +
    142A  GLU*     1.3    62.1    +      -       -      +
    144A  GLN*     3.3     5.7    +      -       -      +
    145A  VAL*     2.9    30.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 142 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    112A  SER*     2.8    21.4    +      -       -      +
    116A  LYS*     2.7    31.3    +      -       -      -
    138A  ILE*     2.8    26.6    +      -       -      +
    139A  GLU      4.2     0.2    -      -       -      +
    141A  VAL*     1.3    75.2    -      -       -      +
    143A  LYS*     1.3    63.6    +      -       -      +
    145A  VAL*     3.8    10.2    -      -       +      +
    146A  TRP*     3.2    16.5    +      -       -      +
     67C  ARG*     3.0    38.0    +      -       -      +
     70C  ALA*     3.6    25.2    -      -       +      +
     71C  ILE*     4.7     2.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 143 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    139A  GLU      3.1    15.1    +      -       -      +
    140A  GLU*     3.4    24.7    +      -       -      +
    142A  GLU*     1.3    73.6    -      -       -      +
    144A  GLN*     1.3    81.7    +      -       -      +
    146A  TRP*     3.1    11.5    +      -       +      +
    147A  MET*     3.0    42.7    +      -       +      +
     66C  GLU*     4.3    22.8    +      -       +      +
     70C  ALA*     4.3     9.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 144 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     49A  LYS*     2.7    38.1    +      -       -      +
     53A  LEU*     3.8    19.7    -      -       +      +
     56A  HIS*     6.2     1.6    -      -       +      +
    108A  TYR*     4.3    21.8    -      -       +      -
    140A  GLU*     2.8    39.7    +      -       +      +
    141A  VAL*     3.8     7.4    -      -       -      +
    143A  LYS*     1.3    90.7    -      -       -      +
    145A  VAL*     1.3    60.2    +      -       -      +
    147A  MET*     3.9     8.4    -      -       -      +
    148A  LEU*     2.9    39.1    +      -       +      +
----------------------------------------------------------
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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
----------------------------------------------------------
    105A  VAL*     4.3     8.5    -      -       +      +
    108A  TYR*     3.5    26.5    -      -       +      +
    109A  LYS*     3.3    50.3    -      -       +      +
    112A  SER*     6.2     0.2    -      -       -      -
    141A  VAL*     2.9    23.5    +      -       +      +
    142A  GLU*     3.8    11.4    -      -       +      +
    143A  LYS      3.3     0.2    -      -       -      -
    144A  GLN*     1.3    74.6    -      -       -      +
    146A  TRP*     1.3    58.7    +      -       -      +
    148A  LEU*     4.2     5.1    -      -       -      +
    149A  SER*     2.8    41.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with TRP 146 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    142A  GLU      3.2    12.2    +      -       -      +
    143A  LYS*     3.1    15.3    +      -       +      +
    145A  VAL*     1.3    76.3    -      -       -      +
    147A  MET*     1.3    84.2    +      -       +      +
    149A  SER*     3.9     5.4    -      -       -      -
    150A  SER*     2.7    48.6    +      -       -      -
     66C  GLU*     3.9    32.5    -      -       +      -
     69C  LEU*     3.7    47.0    -      -       +      +
     70C  ALA*     4.1    14.4    -      -       +      -
     35D  HIS      4.5     0.9    -      -       -      -
     36D  TRP*     3.5    23.6    +      -       -      -
     38D  VAL      5.5     0.2    -      -       -      -
     43D  PHE*     3.9    17.0    -      +       -      -
     47D  HIS*     3.8    23.6    -      +       -      -
----------------------------------------------------------
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Residues in contact with MET 147 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     49A  LYS*     3.9    11.7    -      -       -      +
    143A  LYS*     3.0    39.5    +      -       +      +
    144A  GLN*     3.8    25.1    -      -       -      +
    146A  TRP*     1.3    92.3    -      -       +      +
    148A  LEU*     1.3    58.2    +      -       +      +
    150A  SER*     3.2     3.8    +      -       -      -
    151A  TYR*     2.9    27.9    +      -       -      +
     66C  GLU*     5.3     0.2    -      -       -      +
     43D  PHE*     3.7    26.8    -      -       +      -
     44D  PHE*     4.0    16.7    -      -       +      -
     47D  HIS*     3.6    36.8    -      -       +      +
     48D  GLU*     5.9     1.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 148 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     46A  LEU*     5.7     0.4    -      -       +      -
     49A  LYS*     5.0     5.2    -      -       +      -
     50A  PHE*     5.3     2.2    -      -       +      -
     53A  LEU*     4.5    10.1    -      -       +      -
    101A  VAL*     3.6    24.0    -      -       +      +
    104A  LEU*     4.1    23.3    -      -       +      -
    105A  VAL*     3.6    20.4    -      -       +      -
    108A  TYR*     3.9    32.5    -      -       +      -
    144A  GLN*     2.9    27.3    +      -       +      +
    145A  VAL*     4.2     0.7    -      -       -      +
    147A  MET*     1.3    79.7    -      -       +      +
    149A  SER*     1.3    59.1    +      -       -      +
    151A  TYR*     3.3     8.8    +      -       -      +
    152A  LEU*     3.3    24.3    +      -       -      +
     44D  PHE*     3.9    22.7    -      -       +      -
----------------------------------------------------------
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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
----------------------------------------------------------
    105A  VAL*     4.0    16.3    -      -       -      +
    109A  LYS*     4.4     6.7    +      -       -      -
    145A  VAL*     2.8    39.3    +      -       -      +
    146A  TRP*     3.9     5.4    -      -       -      -
    148A  LEU*     1.3    70.3    -      -       -      +
    150A  SER*     1.4    61.8    +      -       -      +
    152A  LEU*     3.2    11.8    +      -       -      +
    153A  GLY*     3.1    19.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with SER 150 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    146A  TRP*     2.7    46.7    +      -       -      -
    147A  MET      3.2     4.7    +      -       -      -
    149A  SER*     1.4    72.4    -      -       -      +
    151A  TYR*     1.4    62.5    +      -       -      +
    153A  GLY*     3.1     8.0    +      -       -      +
     38D  VAL      4.2     7.5    +      -       -      -
     39D  LYS*     3.7     6.9    -      -       -      -
     40D  GLY      2.8    26.5    +      -       -      -
     43D  PHE*     3.6    26.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with TYR 151 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     42A  HIS*     3.3    29.2    -      +       +      -
     45A  THR*     5.8     1.3    -      -       +      -
     46A  LEU*     3.6    29.3    -      -       +      +
     97A  ALA*     3.9     7.3    -      -       -      +
     98A  SER*     4.3    10.4    +      -       -      -
    101A  VAL*     4.0    17.9    -      -       +      -
    147A  MET      2.9    15.9    +      -       -      +
    148A  LEU*     3.3    10.5    +      -       -      +
    150A  SER*     1.4    71.6    -      -       -      +
    152A  LEU*     1.3    80.9    +      -       +      +
     40D  GLY*     3.1    28.3    -      -       -      -
     41D  PRO*     3.1    41.9    -      -       +      +
     43D  PHE*     4.0     4.3    -      -       +      +
     44D  PHE*     3.9    29.8    -      +       +      -
   1154D  PO4      5.6     0.4    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 152 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     98A  SER*     3.7    40.8    -      -       -      +
    101A  VAL*     3.7    20.6    -      -       +      -
    102A  GLN*     3.5    37.5    -      -       +      +
    105A  VAL*     4.3     7.9    -      -       +      -
    148A  LEU      3.3    10.5    +      -       -      +
    149A  SER*     3.2    11.6    +      -       -      +
    150A  SER      3.2     0.4    -      -       -      -
    151A  TYR*     1.3    89.1    -      -       +      +
    153A  GLY*     1.3    63.1    +      -       -      +
----------------------------------------------------------
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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