Contacts of the helix formed by residues 90 - 119 (chain L) in PDB entry 6O81


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 90 (chain L).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     88L  ARG      3.7     2.5    +      -       -      -
     89L  VAL*     1.3    77.5    -      -       -      +
     91L  PRO*     1.3    72.8    -      -       -      +
     92L  GLU*     3.3    15.5    +      -       -      +
     93L  GLU*     3.3    13.6    +      -       -      +
     94L  ALA*     2.8    28.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with PRO 91 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    131C  SER*     6.0     1.3    -      -       -      +
    134C  ILE*     4.7    10.5    -      -       +      -
    135C  GLU*     5.3    11.9    -      -       +      -
    138C  ASN*     4.2    22.4    -      -       -      +
     89L  VAL      4.6     1.6    -      -       -      +
     90L  SER*     1.3    91.3    -      -       -      +
     92L  GLU*     1.3    55.3    +      -       -      +
     94L  ALA*     3.3     8.3    +      -       +      +
     95L  ILE*     2.9    28.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 92 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     90L  SER*     3.3    10.0    +      -       -      +
     91L  PRO*     1.3    76.8    -      -       -      +
     93L  GLU*     1.3    58.3    +      -       -      +
     95L  ILE*     3.3     6.5    +      -       -      +
     96L  LYS*     2.9    36.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 93 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     18L  VAL*     4.5    13.4    -      -       +      +
     89L  VAL*     4.0    14.4    -      -       +      -
     90L  SER*     3.3    20.7    +      -       -      +
     92L  GLU*     1.3    77.0    -      -       -      +
     94L  ALA*     1.3    58.5    +      -       -      +
     96L  LYS*     3.7    12.9    -      -       -      +
     97L  CYS*     2.9    29.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 94 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     20L  MET*     4.8     0.5    -      -       -      +
     69L  CYS*     4.3    21.0    -      -       +      +
     89L  VAL*     4.0    10.2    -      -       +      +
     90L  SER      2.8    17.9    +      -       -      +
     91L  PRO*     3.6     9.6    -      -       +      +
     92L  GLU      3.2     0.2    -      -       -      -
     93L  GLU*     1.3    73.7    -      -       -      +
     95L  ILE*     1.3    59.7    +      -       -      +
     97L  CYS*     3.4     2.1    +      -       -      +
     98L  GLU*     2.9    29.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 95 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     91L  PRO      2.9    17.1    +      -       -      +
     92L  GLU*     3.3     6.0    +      -       -      +
     94L  ALA*     1.3    72.6    -      -       -      +
     96L  LYS*     1.3    59.7    +      -       -      +
     98L  GLU*     3.3     6.5    +      -       -      +
     99L  ASP*     3.0    30.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 96 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     92L  GLU*     2.9    25.1    +      -       +      +
     93L  GLU*     3.7    10.8    -      -       -      +
     95L  ILE*     1.3    77.7    -      -       +      +
     97L  CYS*     1.3    56.9    +      -       -      +
     99L  ASP*     3.4     5.3    +      -       -      +
    100L  LYS*     2.9    30.2    +      -       -      +
    146L  TYR*     4.7    22.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with CYS 97 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     18L  VAL*     3.7    35.0    -      -       +      +
     19L  VAL      5.4     1.3    -      -       -      -
     20L  MET*     3.7     6.9    -      -       +      +
     69L  CYS*     4.1     9.2    -      -       +      -
     93L  GLU      2.9    18.1    +      -       -      +
     94L  ALA      3.8     3.8    -      -       -      +
     96L  LYS*     1.3    74.0    -      -       -      +
     98L  GLU*     1.3    60.7    +      -       -      +
    100L  LYS*     3.8     8.3    -      -       -      +
    101L  PHE*     2.9    31.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 98 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     20L  MET*     3.8    14.7    -      -       +      +
     94L  ALA      2.9    18.3    +      -       -      +
     95L  ILE*     3.7     8.1    -      -       -      +
     96L  LYS      3.3     0.2    -      -       -      -
     97L  CYS*     1.3    77.4    -      -       -      +
     99L  ASP*     1.3    56.9    +      -       -      +
    101L  PHE*     3.4     4.9    +      -       -      +
    102L  THR*     2.9    29.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with ASP 99 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     95L  ILE      3.0    17.1    +      -       -      +
     96L  LYS*     3.9     5.6    -      -       -      +
     98L  GLU*     1.3    75.9    -      -       -      +
    100L  LYS*     1.3    57.4    +      -       -      +
    102L  THR*     3.3     6.0    +      -       -      -
    103L  LYS*     3.0    49.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 100 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      8L  TYR*     3.2    32.4    -      -       +      -
     18L  VAL      5.0     8.2    +      -       -      +
     37L  GLU*     3.4    17.6    +      -       -      -
     96L  LYS      2.9    18.4    +      -       -      +
     97L  CYS*     3.9     7.4    -      -       -      +
     99L  ASP*     1.3    78.1    -      -       -      +
    101L  PHE*     1.3    57.4    +      -       -      +
    103L  LYS*     3.4    12.1    +      -       -      +
    104L  SER*     2.9    28.1    +      -       -      -
    144L  PRO*     3.4    26.0    -      -       -      +
    145L  GLY*     4.9     4.2    -      -       -      -
    146L  TYR*     3.7    30.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 101 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      7L  PHE*     3.8    27.4    -      +       -      -
     20L  MET*     3.7    37.5    -      -       +      -
     36L  LEU*     3.9    35.7    -      -       +      -
     37L  GLU*     4.5    15.7    -      -       +      +
     67L  ASN*     4.3    11.7    -      -       -      -
     97L  CYS      2.9    19.4    +      -       -      +
     98L  GLU*     3.9     4.9    -      -       -      +
    100L  LYS*     1.3    73.4    -      -       -      +
    102L  THR*     1.3    63.4    +      -       -      +
    104L  SER*     4.5     3.8    -      -       -      -
    105L  LYS*     2.9    48.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with THR 102 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     98L  GLU      2.9    19.1    +      -       -      -
     99L  ASP*     3.6     7.6    -      -       -      -
    101L  PHE*     1.3    79.9    -      -       -      +
    103L  LYS*     1.3    58.5    +      -       -      +
    105L  LYS*     3.4     6.4    +      -       -      +
    106L  THR*     2.9    29.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 103 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     99L  ASP*     3.0    45.6    +      -       +      +
    100L  LYS*     3.5     6.2    -      -       -      +
    102L  THR*     1.3    77.2    -      -       -      +
    104L  SER*     1.3    58.8    +      -       -      +
    106L  THR*     3.3     3.8    +      -       -      -
    107L  VAL*     3.0    27.5    +      -       -      +
    145L  GLY      4.5     3.8    -      -       -      +
    146L  TYR*     3.5    44.1    -      -       -      +
    149L  TYR*     3.6    57.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with SER 104 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      7L  PHE*     3.6    25.0    -      -       -      -
      8L  TYR*     4.1    24.2    -      -       -      -
     37L  GLU*     5.2     0.2    -      -       -      -
    100L  LYS      2.9    19.0    +      -       -      -
    101L  PHE*     4.0     3.8    -      -       -      -
    103L  LYS*     1.3    75.9    -      -       -      +
    105L  LYS*     1.3    58.0    +      -       -      +
    107L  VAL*     3.4     7.4    +      -       -      +
    108L  TYR*     2.9    28.4    +      -       -      +
    145L  GLY*     4.8     8.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 105 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      7L  PHE*     3.7    22.8    -      -       +      -
    101L  PHE*     2.9    38.5    +      -       +      +
    102L  THR*     3.8     6.5    -      -       -      +
    104L  SER*     1.3    72.6    -      -       -      +
    106L  THR*     1.3    61.3    +      -       -      +
    108L  TYR*     3.4     6.1    +      -       +      +
    109L  SER*     2.9    31.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with THR 106 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    102L  THR      2.9    17.8    +      -       -      -
    103L  LYS      3.3     5.6    +      -       -      -
    105L  LYS*     1.3    76.4    -      -       -      +
    107L  VAL*     1.3    57.0    +      -       -      +
    109L  SER*     3.4     6.3    +      -       -      +
    110L  ILE*     2.9    29.1    +      -       -      +
    149L  TYR*     4.3    16.6    -      -       -      -
    182L  ARG*     5.9     0.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 107 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    103L  LYS      3.0    17.4    +      -       -      +
    104L  SER*     3.8     7.0    -      -       -      +
    106L  THR*     1.3    75.9    -      -       -      +
    108L  TYR*     1.3    58.2    +      -       -      +
    110L  ILE*     3.3     5.5    +      -       -      +
    111L  LEU*     3.0    36.9    +      -       +      +
    130L  PHE*     5.6     0.9    -      -       -      -
    134L  ALA*     5.6     3.6    -      -       +      -
    145L  GLY      6.2     0.2    -      -       -      +
    148L  ALA*     5.2     9.0    -      -       +      -
    149L  TYR*     5.1     7.1    -      -       +      +
    152L  PHE*     4.2    26.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 108 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      3L  LEU      5.2     3.1    -      -       -      -
      4L  SER*     4.7    16.2    -      -       -      -
      5L  CYS      4.4    17.9    -      -       -      -
      7L  PHE*     3.4    39.3    -      +       +      -
    104L  SER      2.9    18.1    +      -       -      +
    105L  LYS*     3.6    10.5    -      -       +      +
    107L  VAL*     1.3    77.4    -      -       -      +
    109L  SER*     1.3    61.3    +      -       -      +
    111L  LEU*     3.5     0.9    +      -       -      +
    112L  ARG*     2.9    40.7    +      -       +      +
    126L  LEU*     5.8     1.6    -      -       +      -
    130L  PHE*     3.5    33.6    -      +       +      -
----------------------------------------------------------
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Residues in contact with SER 109 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    105L  LYS*     2.9    20.3    +      -       -      -
    106L  THR*     3.4     7.2    +      -       -      -
    108L  TYR*     1.3    77.8    -      -       -      +
    110L  ILE*     1.3    61.4    +      -       -      +
    112L  ARG*     3.7     6.8    -      -       -      +
    113L  HIS*     2.9    29.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 110 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    106L  THR      2.9    17.0    +      -       -      +
    107L  VAL*     3.7     8.1    -      -       -      +
    108L  TYR      3.3     0.2    -      -       -      -
    109L  SER*     1.3    76.8    -      -       -      +
    111L  LEU*     1.3    62.6    +      -       +      +
    113L  HIS*     3.3     7.0    +      -       -      +
    114L  VAL*     2.9    27.1    +      -       -      +
    152L  PHE*     5.7     4.7    -      -       +      -
    178L  ASN*     4.1    16.7    -      -       +      +
    179L  ILE*     5.4     4.3    -      -       +      +
    182L  ARG*     4.9    17.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 111 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    107L  VAL      3.0    25.9    +      -       -      +
    108L  TYR      4.1     2.5    -      -       -      +
    110L  ILE*     1.3    78.1    -      -       +      +
    112L  ARG*     1.3    60.6    +      -       -      +
    114L  VAL*     3.6     8.6    -      -       +      +
    115L  ALA*     2.9    29.3    +      -       -      +
    126L  LEU*     5.8     0.6    -      -       -      +
    129L  LEU*     4.0     6.5    -      -       +      +
    130L  PHE*     3.7    54.3    -      -       +      +
    133L  THR*     3.8    19.3    -      -       -      -
    134L  ALA*     4.5     7.6    -      -       +      -
    152L  PHE*     3.6    33.2    -      -       +      -
    175L  LEU*     6.4     2.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 112 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    108L  TYR*     2.9    34.7    +      -       +      +
    109L  SER*     3.7     7.6    -      -       -      +
    110L  ILE      3.3     0.2    -      -       -      -
    111L  LEU*     1.3    74.6    -      -       -      +
    113L  HIS*     1.3    60.4    +      -       -      +
    115L  ALA*     3.4     5.5    +      -       -      +
    116L  GLU*     2.9    29.3    +      -       -      +
    126L  LEU*     5.6     5.4    -      -       +      -
    130L  PHE*     5.4     2.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with HIS 113 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    109L  SER      2.9    17.8    +      -       -      +
    110L  ILE*     3.3     6.5    +      -       -      +
    112L  ARG*     1.3    74.8    -      -       -      +
    114L  VAL*     1.3    58.2    +      -       -      +
    116L  GLU*     3.4     6.5    +      -       -      +
    117L  VAL*     2.9    29.5    +      -       -      +
    178L  ASN*     4.9     9.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 114 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    110L  ILE      2.9    17.6    +      -       -      +
    111L  LEU*     3.6    11.0    -      -       +      +
    112L  ARG      3.3     0.2    -      -       -      -
    113L  HIS*     1.3    77.5    -      -       -      +
    115L  ALA*     1.3    56.7    +      -       -      +
    117L  VAL*     3.4     7.2    +      -       -      +
    118L  LEU*     2.9    27.9    +      -       -      +
    129L  LEU*     5.4     3.4    -      -       +      -
    171L  GLU      5.5     1.1    -      -       -      +
    174L  VAL*     4.6     9.1    -      -       +      +
    175L  LEU*     4.4    29.4    -      -       +      +
    178L  ASN*     4.7     5.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 115 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      3L  LEU*     6.0     2.0    -      -       +      -
    111L  LEU      2.9    17.6    +      -       -      +
    112L  ARG      3.9     3.6    -      -       -      +
    114L  VAL*     1.3    75.2    -      -       -      +
    116L  GLU*     1.3    59.7    +      -       -      +
    118L  LEU*     4.2     6.3    -      -       -      +
    119L  GLU      2.8    22.2    +      -       -      -
    120L  TYR*     3.0    19.1    +      -       +      +
    126L  LEU*     3.7    30.5    -      -       +      -
    129L  LEU*     4.1    20.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 116 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      3L  LEU*     6.4     1.8    -      -       +      -
    112L  ARG      2.9    18.5    +      -       -      +
    113L  HIS*     3.7     7.9    -      -       -      +
    114L  VAL      3.3     0.2    -      -       -      -
    115L  ALA*     1.3    75.9    -      -       -      +
    117L  VAL*     1.3    63.0    +      -       -      +
    119L  GLU*     3.4    13.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 117 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    113L  HIS      2.9    17.9    +      -       -      +
    114L  VAL*     3.7     6.7    -      -       -      +
    116L  GLU*     1.3    77.5    -      -       -      +
    118L  LEU*     1.3    59.4    +      -       -      +
    119L  GLU*     3.5     2.1    +      -       -      +
    174L  VAL*     4.7    14.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 118 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    114L  VAL      2.9    17.7    +      -       -      +
    115L  ALA*     3.9     7.4    -      -       -      +
    116L  GLU      3.3     0.2    -      -       -      -
    117L  VAL*     1.3    73.9    -      -       -      +
    119L  GLU*     1.3    68.8    +      -       -      +
    120L  TYR*     3.4     7.7    +      -       +      +
    129L  LEU*     5.0     8.1    -      -       +      -
    171L  GLU*     5.6    12.3    -      -       +      -
    174L  VAL*     5.7     2.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 119 (chain L). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    115L  ALA      2.8     9.2    +      -       -      -
    116L  GLU*     3.4    10.0    +      -       -      +
    117L  VAL      3.3     5.2    -      -       -      +
    118L  LEU*     1.3    80.2    -      -       -      +
    120L  TYR*     1.3    57.3    +      -       -      +
    121L  THR*     3.2     9.3    +      -       -      -
----------------------------------------------------------
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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