Contacts of the helix formed by residues 118 - 142 (chain B) in PDB entry 1LK3


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 SER 118 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     55B  ASP*     2.5    32.7    +      -       -      -
     60B  LEU      5.7     1.6    -      -       -      -
     63B  GLN*     6.0     0.9    -      -       -      -
     64B  ALA*     4.2     7.2    -      -       -      -
     67B  GLU*     3.0    23.9    +      -       -      -
    117B  LYS*     1.3    73.4    -      -       -      +
    119B  LYS*     1.3    62.8    +      -       -      +
    120B  ALA      3.0     8.7    +      -       -      -
    121B  VAL*     3.1    12.8    +      -       -      +
    122B  GLU*     2.9    29.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 119 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     55B  ASP*     5.0     2.3    +      -       -      +
    117B  LYS      3.9     2.0    +      -       -      -
    118B  SER*     1.3    73.1    +      -       -      +
    120B  ALA*     1.3    64.5    +      -       -      +
    122B  GLU*     3.4     7.8    +      -       +      +
    123B  GLN*     3.1    23.1    +      -       +      +
    125L  ALA      5.4     5.2    -      -       -      +
    126L  THR*     3.5    44.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 120 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     51B  SER*     4.2    13.9    -      -       -      +
     52B  LEU*     4.4     9.8    -      -       +      +
     55B  ASP*     3.3    38.2    +      -       +      +
    118B  SER*     3.0     0.8    +      -       -      -
    119B  LYS*     1.3    81.4    -      -       -      +
    121B  VAL*     1.3    60.1    -      -       -      +
    123B  GLN*     3.4     9.5    +      -       -      +
    124B  VAL*     3.3    24.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 121 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     52B  LEU*     4.3     4.9    -      -       +      -
     55B  ASP*     4.2     1.1    -      -       -      +
     64B  ALA*     3.7    26.0    -      -       +      +
     67B  GLU*     3.3    38.6    -      -       +      +
     68B  MET*     4.1    25.4    -      -       +      +
     71B  PHE*     5.5     0.2    -      -       +      -
    118B  SER*     3.1    14.0    +      -       -      +
    120B  ALA*     1.3    71.2    -      -       -      +
    122B  GLU*     1.3    67.0    +      -       -      +
    123B  GLN      3.0     2.0    -      -       -      -
    124B  VAL*     2.8    18.7    +      -       -      +
    125B  LYS*     2.9    34.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 122 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     67B  GLU*     4.6     5.2    -      -       -      +
    117B  LYS*     4.2    36.7    +      -       +      +
    118B  SER      2.9    23.6    +      -       -      +
    119B  LYS*     3.4     7.8    +      -       -      +
    121B  VAL*     1.3    77.4    -      -       -      +
    123B  GLN*     1.3    56.7    +      -       -      +
    125B  LYS*     3.4    29.8    +      -       -      +
    126B  ASN*     2.9    44.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 123 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    119B  LYS*     3.1    14.3    +      -       +      +
    120B  ALA*     3.4    13.5    -      -       -      +
    121B  VAL      3.0     0.8    -      -       -      -
    122B  GLU*     1.3    79.1    -      -       -      +
    124B  VAL*     1.3    57.2    +      -       +      +
    126B  ASN*     4.7    11.7    -      -       -      +
    127B  ALA*     3.1    27.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 124 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     47B  LEU*     3.5    38.7    -      -       +      +
     48B  LEU*     4.3    11.0    -      -       +      -
     52B  LEU*     4.3    24.7    -      -       +      -
     68B  MET*     4.5     8.1    -      -       -      -
     71B  PHE*     4.4    17.7    -      -       +      -
    120B  ALA      3.3    14.3    +      -       -      +
    121B  VAL*     2.8    11.2    +      -       -      +
    123B  GLN*     1.3    76.7    -      -       +      +
    125B  LYS*     1.3    60.4    +      -       +      +
    127B  ALA*     3.1     6.3    +      -       -      +
    128B  PHE*     2.8    28.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 125 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     67B  GLU*     4.9    11.0    +      -       -      +
     70B  GLN*     5.3     5.9    +      -       -      -
     71B  PHE*     4.0    35.4    -      -       +      -
    117B  LYS*     6.2     0.8    -      -       -      +
    121B  VAL*     2.9    33.5    +      -       +      +
    122B  GLU*     3.8    31.2    +      -       -      +
    124B  VAL*     1.3    79.1    -      -       +      +
    126B  ASN*     1.3    57.7    +      -       -      +
    128B  PHE*     3.4     4.6    +      -       -      +
    129B  ASN*     3.0    36.3    +      -       -      +
     57I  TYR*     3.4    31.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 126 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    122B  GLU*     2.9    32.0    +      -       -      +
    123B  GLN*     4.1    12.5    -      -       -      +
    125B  LYS*     1.3    75.9    -      -       -      +
    127B  ALA*     1.3    63.9    +      -       -      +
    129B  ASN*     3.7    13.6    -      -       -      +
    130B  LYS*     3.2    24.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 127 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     47B  LEU*     3.8    16.8    -      -       +      +
    123B  GLN*     3.1    25.4    +      -       +      +
    124B  VAL*     3.4     6.3    -      -       -      +
    126B  ASN*     1.3    74.0    -      -       -      +
    128B  PHE*     1.3    67.0    +      -       -      +
    130B  LYS*     3.5     7.4    +      -       -      +
    131B  LEU*     3.1    28.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 128 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     47B  LEU*     3.7    12.8    -      -       +      +
     71B  PHE*     3.7    29.2    -      +       +      -
     75B  GLU*     4.5     4.0    -      -       +      -
     76B  VAL*     4.0    22.9    -      -       +      -
     79B  GLN*     3.7    27.1    -      -       -      -
    124B  VAL      2.8    16.7    +      -       -      +
    125B  LYS      3.6     2.0    -      -       -      +
    127B  ALA*     1.3    75.5    -      -       -      +
    129B  ASN*     1.3    82.5    +      -       -      +
    131B  LEU*     3.0    17.4    +      -       -      +
    132B  GLN*     3.1    13.3    +      -       -      +
    135B  GLY*     3.4    35.2    -      -       -      -
    136B  ILE*     3.8    15.5    -      -       +      -
    139B  ALA*     4.2     8.3    -      -       +      -
     50I  TYR*     4.6     4.9    -      -       -      -
     57I  TYR*     4.0     3.1    -      +       -      -
----------------------------------------------------------
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Residues in contact with ASN 129 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    125B  LYS*     3.0    20.2    +      -       -      +
    126B  ASN*     3.7    16.2    -      -       -      +
    127B  ALA      3.4     0.2    -      -       -      -
    128B  PHE*     1.3    83.8    -      -       -      +
    130B  LYS*     1.3    57.9    +      -       -      +
    132B  GLN*     3.0    23.6    +      -       -      +
     50I  TYR*     4.6     0.8    +      -       -      -
     57I  TYR*     2.7    35.6    +      -       -      -
     58I  THR      3.4    17.0    -      -       -      +
     59I  ASN*     3.3    43.8    +      -       -      +
     60I  TYR      5.1     0.7    +      -       -      +
     93M  GLY*     4.4     0.5    -      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 130 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    126B  ASN      3.2    14.6    +      -       -      +
    127B  ALA*     3.6     8.1    -      -       -      +
    129B  ASN*     1.3    80.7    -      -       -      +
    131B  LEU*     1.3    57.8    +      -       +      +
     62I  GLU*     4.7    17.7    +      -       -      +
      1M  ASP*     2.9    33.9    +      -       -      +
     92M  ASN*     4.6     0.9    -      -       -      +
     93M  GLY*     2.9    49.2    +      -       -      +
     94M  PRO*     3.8     3.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 131 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     45B  ASN*     5.5     2.7    -      -       +      +
     47B  LEU*     4.4    11.0    -      -       +      -
    127B  ALA*     3.1    23.9    +      -       +      +
    128B  PHE*     3.0     7.6    +      -       -      +
    130B  LYS*     1.3    77.9    -      -       +      +
    132B  GLN*     1.3    63.5    +      -       -      +
    134B  LYS*     3.1    31.4    +      -       +      +
    135B  GLY*     3.3    24.6    +      -       -      +
    138B  LYS*     3.9    28.7    -      -       +      -
     91M  TRP      2.9    21.8    -      -       -      +
     92M  ASN*     3.9     2.2    -      -       -      +
     93M  GLY      4.2     0.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLN 132 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    128B  PHE*     3.1     8.3    +      -       -      +
    129B  ASN*     3.0    13.9    +      -       -      +
    131B  LEU*     1.3    79.2    -      -       -      +
    133B  GLU*     1.3    65.4    +      -       -      +
    135B  GLY*     2.9    19.8    +      -       -      -
    136B  ILE*     3.3    10.2    +      -       -      +
     47I  TRP*     3.9    12.0    -      -       -      -
     50I  TYR*     4.1     8.7    -      -       -      -
     59I  ASN*     3.6    21.3    +      -       -      +
    104I  ASN*     3.6    28.0    +      -       -      +
     90M  SER      3.4    15.0    -      -       -      +
     92M  ASN      3.5     4.5    -      -       -      +
     93M  GLY*     3.4    30.0    -      -       -      +
     95M  LEU*     3.6    26.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 133 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     83B  GLN*     4.8     0.7    -      -       -      +
    131B  LEU      3.3     0.2    +      -       -      -
    132B  GLN*     1.3    78.6    -      -       -      +
    134B  LYS*     1.3    65.7    +      -       -      +
    136B  ILE*     3.1    28.3    +      -       +      +
    137B  TYR*     3.4    12.6    -      -       -      -
    102I  GLY      3.2    19.3    -      -       -      +
    104I  ASN*     2.8    45.3    +      -       -      +
    105I  TRP*     3.8     1.8    -      -       -      -
     31M  ARG*     2.7    33.5    +      -       -      +
     90M  SER*     2.8    37.5    +      -       -      +
     91M  TRP*     3.8    13.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 134 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39B  MET*     3.7     7.3    -      -       +      +
     42B  GLN*     2.9    40.8    -      -       -      +
    131B  LEU*     3.1    27.5    +      -       +      +
    133B  GLU*     1.3    77.1    -      -       -      +
    135B  GLY*     1.3    56.7    +      -       -      +
    137B  TYR*     3.2     3.6    +      -       -      +
    138B  LYS*     2.9    36.4    +      -       +      +
     91M  TRP*     3.2    53.8    +      -       +      +
     92M  ASN*     4.5     6.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 135 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     47B  LEU*     4.5     0.7    -      -       -      +
    128B  PHE*     3.4    16.4    -      -       -      -
    131B  LEU*     3.3    33.5    +      -       -      +
    132B  GLN      2.9     8.4    +      -       -      -
    134B  LYS*     1.3    77.1    -      -       -      +
    136B  ILE*     1.3    58.5    +      -       -      +
    138B  LYS*     3.9     1.9    -      -       -      +
    139B  ALA*     2.9    32.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 136 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     37B  PHE*     4.8     0.9    -      -       +      -
     76B  VAL*     4.5     4.7    -      -       +      +
     79B  GLN*     3.6    35.9    -      -       +      +
     80B  ALA*     3.6    34.5    -      -       +      +
     83B  GLN*     3.7    19.1    -      -       +      +
    128B  PHE*     3.9    17.7    -      -       +      -
    132B  GLN      3.3     6.5    +      -       -      +
    133B  GLU*     3.1    27.7    +      -       +      +
    135B  GLY*     1.3    75.5    -      -       -      +
    137B  TYR*     1.3    66.7    +      -       +      +
    139B  ALA*     4.1     1.1    -      -       -      +
    140B  MET*     3.1    31.0    +      -       +      +
    102I  GLY*     3.7    13.0    -      -       -      -
    104I  ASN*     5.2     0.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 137 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     36B  PHE*     3.6    43.6    -      +       -      -
     37B  PHE*     3.8    32.8    -      +       -      +
     39B  MET*     3.6    24.5    -      -       +      -
     83B  GLN*     3.6    29.9    +      -       +      +
    133B  GLU      3.4    13.9    -      -       -      -
    134B  LYS      3.2     8.2    +      -       -      +
    136B  ILE*     1.3    82.0    -      -       +      +
    138B  LYS*     1.3    57.4    +      -       -      +
    140B  MET*     3.3     2.1    +      -       -      +
    141B  SER*     2.9    30.7    +      -       -      -
     31M  ARG*     3.2    22.4    +      -       -      -
     91M  TRP*     3.6    19.7    -      +       -      -
----------------------------------------------------------
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Residues in contact with LYS 138 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39B  MET*     3.9     6.8    -      -       +      +
     42B  GLN*     3.9    22.4    +      -       -      +
     44B  ASP*     4.8     4.2    -      -       -      +
     45B  ASN*     3.4    43.2    +      -       -      +
     46B  LEU*     5.9     0.4    -      -       -      +
     47B  LEU*     4.3     8.3    -      -       +      -
    131B  LEU*     3.9    24.7    -      -       +      -
    134B  LYS*     2.9    30.2    +      -       -      +
    135B  GLY*     3.9     5.6    -      -       -      +
    137B  TYR*     1.3    77.7    -      -       -      +
    139B  ALA*     1.3    62.7    +      -       -      +
    141B  SER*     3.0     9.1    +      -       -      +
    142B  GLU*     3.0    48.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 139 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     47B  LEU*     3.4    26.6    -      -       +      +
     71B  PHE*     5.3     0.2    -      -       +      -
     72B  TYR*     2.8    36.5    +      -       +      +
     76B  VAL*     3.9    24.2    -      -       +      -
    128B  PHE*     4.2     6.3    -      -       +      -
    135B  GLY      2.9    22.5    +      -       -      +
    138B  LYS*     1.3    74.2    -      -       -      +
    140B  MET*     1.3    61.6    +      -       -      +
    142B  GLU*     3.8     1.9    +      -       -      -
    143B  PHE      3.5     7.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with MET 140 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30B  PHE*     2.9    24.2    -      -       -      -
     33B  VAL*     4.5     4.7    -      -       +      -
     37B  PHE*     3.5    41.3    -      -       +      -
     72B  TYR*     4.8     4.3    -      -       -      -
     76B  VAL*     3.8    21.3    -      -       +      -
     77B  MET*     4.5    11.2    -      -       +      -
     80B  ALA*     3.6    21.5    -      -       +      -
     91B  VAL*     4.1    21.8    -      -       +      -
     94B  LEU*     3.9    25.8    -      -       +      -
    136B  ILE      3.1    21.4    +      -       -      +
    137B  TYR      3.7     0.4    -      -       -      +
    138B  LYS      3.1     0.2    -      -       -      -
    139B  ALA*     1.3    76.5    -      -       -      +
    141B  SER*     1.3    67.1    +      -       -      +
    143B  PHE*     3.0     7.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 141 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30B  PHE*     3.1    23.2    -      -       -      -
     34B  LYS*     5.4     2.9    -      -       -      +
     37B  PHE*     4.0    19.9    -      -       -      +
     38B  GLN*     4.1    31.6    +      -       -      +
     39B  MET*     5.0     1.9    -      -       -      +
    137B  TYR      2.9    15.0    +      -       -      -
    138B  LYS*     3.0    15.1    +      -       -      +
    140B  MET*     1.3    76.0    -      -       -      +
    142B  GLU*     1.3    67.3    +      -       -      +
    143B  PHE      3.2     0.3    +      -       -      -
    144B  ASP*     3.3     6.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 142 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     46B  LEU*     3.1    22.4    +      -       +      +
     47B  LEU*     2.9    20.5    +      -       -      +
     48B  LEU*     2.8    46.0    +      -       +      +
    138B  LYS*     3.0    36.5    +      -       +      +
    139B  ALA*     3.9     4.9    -      -       -      +
    140B  MET      3.2     0.2    -      -       -      -
    141B  SER*     1.3    85.2    +      -       -      +
    143B  PHE*     1.3    62.7    +      -       -      +
    144B  ASP*     3.2     7.0    -      -       -      -
    145B  ILE*     3.0    29.5    +      -       +      +
    146B  PHE      3.2     7.4    +      -       -      -
----------------------------------------------------------
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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