Contacts of the helix formed by residues 126 - 149 (chain A) in PDB entry 4NEF


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 THR 126 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    121A  LEU*     4.1     1.1    -      -       -      -
    124A  SER      4.5     6.7    -      -       -      +
    125A  THR*     1.3    75.2    -      -       -      +
    127A  ALA*     1.4    53.2    +      -       -      +
    128A  GLY*     3.8     4.1    +      -       -      -
    129A  GLN*     3.0    37.2    +      -       -      +
    130A  ALA*     2.8    32.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 127 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    121A  LEU*     3.6    20.7    -      -       +      +
    126A  THR*     1.4    72.0    -      -       -      +
    128A  GLY*     1.3    55.6    +      -       -      +
    130A  ALA*     3.7     4.9    -      -       -      +
    131A  VAL*     2.9    31.8    +      -       -      +
    200A  ASP*     4.9     5.8    -      -       +      +
    202A  TRP*     3.7    26.9    -      -       +      +
    203A  VAL*     3.7    12.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 128 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    126A  THR*     3.2     5.2    +      -       -      -
    127A  ALA*     1.3    75.6    -      -       -      +
    129A  GLN*     1.4    56.9    +      -       -      +
    131A  VAL*     3.4    15.9    -      -       -      +
    132A  THR*     2.7    27.9    +      -       -      -
    202A  TRP*     5.0     3.1    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLN 129 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    124A  SER      4.8     0.7    -      -       -      +
    125A  THR*     3.8    10.6    -      -       +      +
    126A  THR*     3.0    41.3    +      -       -      +
    128A  GLY*     1.4    74.4    -      -       -      +
    130A  ALA*     1.3    63.8    +      -       -      +
    132A  THR*     3.4     3.5    +      -       -      -
    133A  VAL*     3.2    18.4    +      -       -      +
    106D  GLU*     3.2    28.0    +      -       -      +
    107D  ILE*     3.4    43.6    -      -       -      +
    108D  THR      3.9    10.1    +      -       -      -
    109D  PRO*     4.2    10.6    -      -       -      +
    113D  ARG*     4.5     6.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 130 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    121A  LEU*     4.3     8.3    -      -       +      -
    125A  THR*     3.8    12.9    -      -       +      +
    126A  THR      2.8    15.0    +      -       -      +
    127A  ALA*     3.7     9.0    -      -       -      +
    129A  GLN*     1.3    75.1    -      -       -      +
    131A  VAL*     1.4    58.7    +      -       -      +
    133A  VAL*     3.2     8.7    +      -       -      +
    134A  GLU*     3.0    31.7    +      -       -      +
    178A  TYR*     5.2     0.7    -      -       -      -
    179A  THR*     3.6    26.3    -      -       +      +
    203A  VAL*     3.8     8.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 131 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    127A  ALA      2.9    20.1    +      -       -      +
    128A  GLY*     3.4    20.9    -      -       -      +
    130A  ALA*     1.4    71.8    -      -       -      +
    132A  THR*     1.4    58.1    +      -       -      +
    134A  GLU*     4.5     1.3    -      -       -      -
    135A  LEU*     3.1    27.5    +      -       -      +
    202A  TRP*     3.8    28.3    -      -       +      -
    203A  VAL*     3.6    15.6    -      -       +      +
    206A  ILE*     3.9    10.8    -      -       +      -
    207A  GLY*     3.4    28.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 132 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    128A  GLY      2.7    21.5    +      -       -      -
    129A  GLN*     3.5     9.5    -      -       -      -
    130A  ALA      3.2     0.6    -      -       -      -
    131A  VAL*     1.4    76.5    -      -       -      +
    133A  VAL*     1.4    63.4    +      -       -      +
    135A  LEU*     3.4    10.5    -      -       +      +
    136A  PHE*     3.2    45.4    +      -       +      -
    103D  LEU*     4.4     4.7    -      -       +      -
    107D  ILE*     3.6    20.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 133 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    129A  GLN      3.2    16.4    +      -       -      +
    130A  ALA*     3.2     7.9    +      -       -      +
    132A  THR*     1.4    73.4    -      -       -      +
    134A  GLU*     1.4    57.5    +      -       +      +
    136A  PHE*     3.0     6.4    +      -       -      +
    137A  LEU*     2.9    54.2    +      -       +      +
    174A  LEU*     4.4     9.6    -      -       +      -
    175A  GLY*     4.5     1.6    -      -       -      -
    178A  TYR*     3.8    41.1    -      -       +      -
    179A  THR*     5.5     1.3    -      -       -      +
     25D  PHE*     4.6     5.3    -      -       +      -
    107D  ILE*     3.7    31.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 134 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    130A  ALA      3.0    18.5    +      -       -      +
    131A  VAL      3.9     0.4    -      -       -      +
    133A  VAL*     1.4    74.4    -      -       +      +
    135A  LEU*     1.4    58.1    +      -       -      +
    137A  LEU*     3.7    14.7    -      -       +      +
    138A  THR*     2.9    32.7    +      -       -      -
    179A  THR*     2.7    34.2    +      -       +      +
    182A  SER*     3.0    28.0    +      -       -      -
    183A  MET*     2.8    28.2    +      -       -      -
    203A  VAL*     4.3    12.6    -      -       +      +
    204A  PHE*     4.8     1.8    -      -       +      -
    207A  GLY*     3.8    23.5    -      -       -      +
    208A  PRO*     3.5     9.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 135 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    131A  VAL      3.1    14.6    +      -       -      +
    132A  THR*     3.4    15.5    -      -       +      +
    134A  GLU*     1.4    74.9    -      -       -      +
    136A  PHE*     1.4    84.9    +      -       +      +
    139A  LEU*     2.9    32.7    +      -       +      +
    207A  GLY*     3.4    13.6    +      -       -      +
    210A  VAL*     3.7    26.5    -      -       +      -
    211A  GLY*     3.3    22.4    -      -       -      +
    214A  LEU*     4.3    18.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 136 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    132A  THR*     3.2    30.0    +      -       +      -
    133A  VAL      3.0     7.1    +      -       -      +
    135A  LEU*     1.4    94.3    -      -       +      +
    137A  LEU*     1.4    63.3    +      -       -      +
    139A  LEU*     3.9    12.6    -      -       +      +
    140A  GLN*     3.3    24.8    +      -       -      +
     18D  LEU*     5.9     3.4    -      -       +      -
     21D  LEU*     4.2    18.4    -      -       +      -
     22D  LEU*     3.7    23.5    -      -       +      +
     25D  PHE*     3.7    27.6    -      +       +      -
     26D  PHE*     3.6     6.6    -      -       +      -
    103D  LEU*     3.6    41.3    -      -       +      -
----------------------------------------------------------
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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
----------------------------------------------------------
    133A  VAL*     2.9    24.3    +      -       +      +
    134A  GLU*     3.7    32.5    -      -       -      +
    135A  LEU      3.3     0.2    -      -       -      -
    136A  PHE*     1.4    74.1    -      -       -      +
    138A  THR*     1.4    61.1    +      -       -      +
    140A  GLN*     2.7    31.6    +      -       -      +
    141A  LEU      3.4     0.9    +      -       -      -
    171A  GLY*     3.3    23.8    -      -       -      +
    174A  LEU*     3.9    13.9    -      -       +      -
    175A  GLY*     3.8    21.5    -      -       -      +
    181A  CYS*     4.0    11.9    -      -       -      -
    183A  MET*     3.2    19.2    -      -       +      +
     26D  PHE*     3.5    25.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 138 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     68A  ASN*     5.2     0.4    -      -       -      +
     70A  ALA*     4.0     5.4    -      -       +      -
     71A  VAL*     5.7     0.4    -      -       +      -
    134A  GLU      2.9    17.3    +      -       -      -
    135A  LEU      4.1     2.2    -      -       -      -
    137A  LEU*     1.4    74.1    -      -       -      +
    139A  LEU*     1.4    56.7    +      -       -      +
    141A  LEU*     3.4     9.1    +      -       +      -
    142A  VAL*     3.0    34.5    +      -       +      +
    183A  MET*     3.4    33.3    -      -       +      +
    208A  PRO*     3.3    36.7    -      -       +      +
    211A  GLY      4.2     2.2    -      -       -      -
    212A  ALA*     4.0    14.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 139 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    135A  LEU*     2.9    25.5    +      -       +      +
    136A  PHE*     3.9    14.6    -      -       +      +
    137A  LEU      3.4     0.2    -      -       -      -
    138A  THR*     1.4    76.5    -      -       -      +
    140A  GLN*     1.4    62.0    +      -       -      +
    142A  VAL*     3.4     2.3    +      -       -      +
    143A  LEU*     3.1    33.5    +      -       +      +
    211A  GLY      3.4    10.7    +      -       -      +
    214A  LEU*     3.7    27.4    -      -       +      -
    215A  GLY*     3.6    27.1    -      -       -      +
    218A  LEU*     4.3     8.5    -      -       +      -
     18D  LEU*     4.6    11.0    -      -       +      -
     22D  LEU*     3.9    35.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLN 140 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    136A  PHE      3.3    12.4    +      -       -      +
    137A  LEU*     2.7    22.9    +      -       -      +
    139A  LEU*     1.4    75.5    -      -       -      +
    141A  LEU*     1.4    72.0    -      -       -      +
    143A  LEU*     3.2    13.2    +      -       -      +
    144A  CYS*     3.0    23.2    +      -       -      +
    167A  SER*     2.9    38.2    +      -       -      +
    170A  LEU*     3.3    25.8    -      -       +      +
    171A  GLY*     4.1     5.9    -      -       -      -
    183A  MET*     3.3    11.9    -      -       -      +
     22D  LEU*     4.4    17.3    -      -       +      -
     26D  PHE*     3.4    19.7    -      -       +      -
     54D  THR*     3.4     9.9    -      -       +      +
     55D  LEU*     5.6     3.8    -      -       +      -
     58D  ALA*     5.1     0.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 141 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     52A  ILE*     5.6     0.2    -      -       +      -
     68A  ASN*     4.3    20.0    -      -       -      +
     71A  VAL*     4.7     5.4    -      -       +      -
    137A  LEU      3.4     9.8    +      -       -      +
    138A  THR*     3.6    11.7    -      -       +      +
    139A  LEU      3.3     0.2    -      -       -      -
    140A  GLN*     1.4    81.4    -      -       -      +
    142A  VAL*     1.3    57.4    +      -       +      +
    144A  CYS*     3.1     5.5    +      -       -      +
    145A  ILE*     2.9    56.0    +      -       +      +
    164A  ILE*     4.2     4.5    -      -       +      +
    167A  SER*     3.4    19.3    -      -       -      +
    168A  VAL*     3.6    31.4    -      -       +      +
    183A  MET*     3.8    29.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 142 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     71A  VAL*     4.3    20.6    -      -       +      -
     74A  ALA*     3.9     7.6    -      -       +      -
    138A  THR*     3.0    23.7    +      -       +      +
    139A  LEU      3.9     3.4    -      -       -      +
    141A  LEU*     1.3    73.7    -      -       +      +
    143A  LEU*     1.3    56.6    +      -       -      +
    145A  ILE*     4.4     5.6    -      -       +      -
    146A  PHE*     3.0    61.2    +      -       +      -
    212A  ALA*     3.6    43.1    -      -       +      +
    215A  GLY*     3.8     3.6    -      -       -      -
    216A  SER      3.7    11.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 143 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    139A  LEU*     3.1    25.1    +      -       +      +
    140A  GLN*     3.2    11.2    +      -       -      +
    142A  VAL*     1.3    75.7    -      -       -      +
    144A  CYS*     1.3    59.8    +      -       -      +
    146A  PHE*     3.7     4.3    +      -       -      +
    147A  ALA*     3.3    23.2    +      -       -      +
    215A  GLY*     3.3    33.9    -      -       -      +
    218A  LEU*     4.7     7.6    -      -       +      -
    219A  TYR*     4.2    15.3    -      -       +      -
    223A  LEU*     4.6     9.4    -      -       +      -
     18D  LEU*     4.0    26.2    -      -       +      -
     22D  LEU*     4.3    18.2    -      -       +      -
     55D  LEU*     5.7     0.9    -      -       +      -
     58D  ALA*     3.8    17.3    -      -       +      +
     59D  LEU*     4.7     9.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with CYS 144 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    140A  GLN      3.0     7.6    +      -       -      +
    141A  LEU      3.5     7.6    -      -       -      +
    143A  LEU*     1.3    73.8    -      -       -      +
    145A  ILE*     1.4    52.7    +      -       -      +
    147A  ALA*     3.3     2.4    +      -       -      +
    148A  SER*     2.8    42.8    +      -       -      -
    163A  SER*     3.6    30.3    -      -       -      -
    164A  ILE*     3.9     3.8    -      -       -      -
    167A  SER*     3.6    20.6    -      -       -      +
     54D  THR*     4.0    14.8    -      -       +      +
     57D  GLN*     3.7    23.8    -      -       -      -
     58D  ALA*     3.9     8.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 145 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     52A  ILE*     6.1     0.4    -      -       +      -
     64A  GLY      6.0     2.0    -      -       -      +
     65A  ALA      5.9     2.0    -      -       -      +
     66A  HIS      5.5     1.6    -      -       -      +
     71A  VAL*     3.6    43.7    -      -       +      -
     75A  CYS*     5.7     5.4    -      -       -      -
    141A  LEU*     2.9    39.8    +      -       +      +
    142A  VAL*     3.9     7.0    -      -       +      +
    144A  CYS*     1.4    70.7    -      -       -      +
    146A  PHE*     1.3    62.5    +      -       +      +
    148A  SER      3.4     0.7    +      -       -      -
    149A  THR*     2.8    46.1    +      -       +      +
    164A  ILE*     3.7    37.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 146 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     71A  VAL*     6.4     0.7    -      -       +      -
     74A  ALA*     3.6    33.9    -      -       +      -
     75A  CYS*     4.2     9.9    -      -       -      -
     80A  HIS*     3.1    38.1    -      +       -      -
    142A  VAL*     3.0    50.4    +      -       +      +
    143A  LEU      4.0     1.6    -      -       -      +
    145A  ILE*     1.3    82.3    -      -       +      +
    147A  ALA*     1.4    58.3    +      -       -      +
    149A  THR*     3.7     7.0    +      -       -      -
    150A  ASP*     3.3    22.3    +      -       -      +
    216A  SER*     3.7     9.6    -      -       -      -
    219A  TYR*     3.6    33.3    +      +       +      -
    220A  ASN*     3.2    23.8    -      -       -      -
    302A   ZN      4.4     0.9    -      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 147 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    143A  LEU      3.3    15.2    +      -       -      +
    144A  CYS      3.3     3.7    +      -       -      +
    146A  PHE*     1.4    74.2    -      -       -      +
    148A  SER*     1.3    60.5    +      -       -      +
    149A  THR      3.3     0.2    -      -       -      -
    150A  ASP*     3.3     7.8    +      -       -      +
    153A  ARG*     2.8    36.4    +      -       -      +
    219A  TYR*     3.5    18.8    +      -       +      +
     57D  GLN*     3.3    27.1    -      -       +      +
     58D  ALA*     3.8    11.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with SER 148 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    144A  CYS*     2.8    24.0    +      -       -      -
    145A  ILE      3.4     0.9    +      -       -      -
    147A  ALA*     1.3    77.0    -      -       -      +
    149A  THR*     1.3    58.0    +      -       -      +
    150A  ASP      3.4     2.4    +      -       -      +
    153A  ARG*     4.2     2.5    +      -       -      +
    155A  GLU*     5.4     1.6    -      -       -      +
    160A  PRO*     3.4    35.6    +      -       -      +
    164A  ILE*     3.7    28.3    -      -       -      +
     57D  GLN*     2.8    30.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 149 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     56A  VAL*     6.0     2.9    -      -       +      -
     64A  GLY      5.4     8.1    -      -       -      +
    145A  ILE*     2.8    31.0    +      -       +      +
    146A  PHE*     3.7     8.6    +      -       -      -
    147A  ALA      3.3     0.2    -      -       -      -
    148A  SER*     1.3    79.5    -      -       -      +
    150A  ASP*     1.4    60.9    +      -       -      +
    151A  GLU*     3.6    14.0    +      -       -      +
    160A  PRO*     6.2     0.4    -      -       +      -
    164A  ILE*     4.7    13.2    -      -       +      -
----------------------------------------------------------
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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