Contacts of the helix formed by residues 90 - 118 (chain A) in PDB entry 2A19


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 A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     88A  ARG      4.0     1.0    +      -       -      -
     89A  VAL*     1.3    78.7    -      -       -      +
     91A  SER*     1.3    59.6    +      -       -      +
     92A  GLU*     3.6    11.3    -      -       -      +
     93A  ASP*     3.0    34.9    +      -       -      +
     94A  ILE*     3.1    27.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 91 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     90A  SER*     1.3    71.5    -      -       -      +
     92A  GLU*     1.3    65.5    +      -       -      +
     94A  ILE*     3.3    13.6    +      -       -      +
     95A  ILE*     3.2    35.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 92 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     90A  SER*     3.6    11.1    +      -       -      +
     91A  SER*     1.3    79.6    -      -       -      +
     93A  ASP*     1.3    64.3    +      -       -      +
     95A  ILE*     3.4     7.9    +      -       -      +
     96A  LYS*     3.1    53.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 93 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     18A  ILE*     4.0    32.4    -      -       +      +
     88A  ARG      4.1     4.9    -      -       -      +
     89A  VAL*     3.7    17.0    -      -       +      -
     90A  SER*     3.0    37.7    +      -       -      +
     92A  GLU*     1.3    80.2    -      -       -      +
     94A  ILE*     1.3    55.2    +      -       -      +
     96A  LYS*     3.7     7.2    -      -       -      +
     97A  CYS*     2.7    38.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 94 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     68A  ASP*     6.2     0.2    -      -       -      +
     69A  VAL*     4.1    24.7    -      -       +      +
     89A  VAL*     3.8    17.0    -      -       +      +
     90A  SER      3.1    19.8    +      -       -      +
     91A  SER*     3.3    14.8    +      -       -      +
     93A  ASP*     1.3    75.0    -      -       -      +
     95A  ILE*     1.3    63.1    +      -       +      +
     97A  CYS*     3.2     2.9    +      -       -      +
     98A  GLU*     2.8    36.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 95 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     91A  SER*     3.2    23.1    +      -       -      +
     92A  GLU*     3.8     8.7    -      -       -      +
     94A  ILE*     1.3    79.3    -      -       +      +
     96A  LYS*     1.3    55.0    +      -       +      +
     98A  GLU*     3.0     8.4    +      -       -      +
     99A  GLU*     2.8    55.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 96 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     92A  GLU*     3.1    43.4    +      -       -      +
     93A  ASP*     4.0     7.6    -      -       -      +
     95A  ILE*     1.3    79.4    -      -       +      +
     97A  CYS*     1.3    63.2    +      -       -      +
     99A  GLU*     3.9    14.4    -      -       -      +
    100A  LYS*     3.2    24.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with CYS 97 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     18A  ILE*     3.8    25.1    -      -       +      +
     19A  VAL      3.6    31.0    -      -       -      -
     20A  MET*     3.7    12.1    -      -       -      -
     37A  GLU*     5.0     3.5    -      -       -      +
     69A  VAL*     3.8    21.3    -      -       +      -
     93A  ASP      2.7    22.2    +      -       -      +
     94A  ILE      3.6     3.6    -      -       -      +
     96A  LYS*     1.3    74.5    -      -       -      +
     98A  GLU*     1.3    56.1    +      -       -      +
    100A  LYS*     3.9     7.1    -      -       -      +
    101A  TYR*     3.0    32.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 98 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     20A  MET*     3.7    17.5    -      -       +      +
     67A  ASN*     5.5     1.0    -      -       -      +
     69A  VAL*     5.5     0.7    -      -       +      -
     94A  ILE*     2.8    27.4    +      -       +      +
     95A  ILE*     3.0     7.2    +      -       -      +
     97A  CYS*     1.3    72.1    -      -       -      +
     99A  GLU*     1.3    59.2    +      -       +      +
    101A  TYR*     3.6    14.4    -      -       -      +
    102A  GLN*     2.8    70.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 99 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     95A  ILE*     2.8    43.2    +      -       +      +
     96A  LYS*     3.9    12.5    -      -       -      +
     98A  GLU*     1.3    73.6    -      -       +      +
    100A  LYS*     1.3    63.2    +      -       -      +
    102A  GLN*     3.3     5.5    +      -       -      +
    103A  LYS*     3.0    43.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 100 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      8A  TYR*     3.2    44.7    -      -       -      +
     18A  ILE      5.5     7.2    -      -       -      +
     37A  GLU*     4.2     5.8    -      -       -      +
     96A  LYS      3.2    14.7    +      -       -      +
     97A  CYS*     3.9     7.4    -      -       -      +
     99A  GLU*     1.3    78.4    -      -       -      +
    101A  TYR*     1.3    58.1    +      -       -      +
    103A  LYS*     3.3     8.7    +      -       -      +
    104A  SER*     2.8    33.1    +      -       -      -
    139A  HIS*     3.8    17.3    +      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 101 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      7A  PHE*     4.2    15.0    -      +       -      -
     20A  MET*     3.8    27.6    -      -       +      -
     36A  LEU*     3.3    41.2    -      -       +      +
     37A  GLU*     4.2    21.4    +      -       +      +
     67A  ASN*     4.1    13.8    +      -       -      -
     97A  CYS      3.0    19.7    +      -       -      +
     98A  GLU*     3.6    10.1    -      -       -      +
    100A  LYS*     1.3    77.1    -      -       -      +
    102A  GLN*     1.3    77.0    +      -       -      +
    104A  SER*     3.1     4.7    +      -       -      -
    105A  LYS*     2.7    64.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 102 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     98A  GLU*     2.8    56.9    +      -       -      +
     99A  GLU*     3.8     4.7    -      -       -      +
    101A  TYR*     1.3    90.2    -      -       -      +
    103A  LYS*     1.3    64.5    +      -       +      +
    105A  LYS*     3.3    15.1    +      -       -      +
    106A  THR*     3.0    27.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 103 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     99A  GLU*     3.0    35.8    +      -       +      +
    100A  LYS*     3.7     6.7    -      -       -      +
    102A  GLN*     1.3    77.5    -      -       +      +
    104A  SER*     1.3    56.7    +      -       -      +
    106A  THR*     3.3     3.1    +      -       -      -
    107A  VAL*     3.0    31.9    +      -       -      +
    139A  HIS*     3.9    14.8    -      -       +      -
    141A  TYR*     3.4    45.0    -      -       +      -
    142A  GLU*     2.6    32.9    +      -       -      -
    145A  LYS*     5.7     0.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with SER 104 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      7A  PHE*     3.3    33.6    -      -       -      -
      8A  TYR*     3.0    21.4    +      -       -      -
    100A  LYS      2.8    13.6    +      -       -      -
    101A  TYR*     3.5     4.5    -      -       -      -
    103A  LYS*     1.3    74.7    -      -       -      +
    105A  LYS*     1.3    64.0    +      -       -      +
    107A  VAL*     3.4     3.9    +      -       -      +
    108A  HIS*     3.0    25.3    +      -       -      +
    126A  TYR*     4.6     0.7    +      -       -      -
    139A  HIS*     2.8    29.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 105 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      7A  PHE*     4.2     7.8    -      -       +      -
    101A  TYR*     2.7    55.3    +      -       +      +
    102A  GLN*     3.7    17.5    +      -       -      +
    104A  SER*     1.3    74.0    -      -       -      +
    106A  THR*     1.3    56.5    +      -       -      +
    108A  HIS*     3.4     8.1    -      -       +      +
    109A  SER*     2.9    30.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with THR 106 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    102A  GLN      3.0    14.1    +      -       -      -
    103A  LYS      3.5     8.1    -      -       -      -
    105A  LYS*     1.3    74.0    -      -       -      +
    107A  VAL*     1.3    67.5    +      -       -      +
    109A  SER*     3.1     7.3    +      -       -      -
    110A  ILE*     2.9    46.3    +      -       +      +
    141A  TYR*     3.7    27.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 107 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    103A  LYS      3.0    17.3    +      -       -      +
    104A  SER*     3.8     6.1    -      -       -      +
    106A  THR*     1.3    74.8    -      -       +      +
    108A  HIS*     1.3    55.1    +      -       -      +
    110A  ILE*     3.1    10.1    +      -       -      +
    111A  LEU*     2.7    56.1    +      -       +      +
    126A  TYR*     4.4    11.4    -      -       +      +
    139A  HIS*     4.2     5.2    -      -       +      -
    140A  ALA*     4.2    19.1    -      -       +      -
    141A  TYR*     3.8    35.4    -      -       +      +
    144A  PHE*     4.3    14.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with HIS 108 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      3A  SER      3.8    12.0    +      -       -      -
      4A  HIS*     4.8     0.7    -      -       -      -
      5A  CYS      3.6    20.6    +      -       -      -
      7A  PHE*     3.5    24.9    -      +       +      -
    104A  SER      3.0    16.2    +      -       -      +
    105A  LYS*     3.4     6.5    -      -       +      +
    107A  VAL*     1.3    77.7    -      -       -      +
    109A  SER*     1.3    54.7    +      -       -      +
    111A  LEU*     3.7     0.9    -      -       -      +
    112A  ARG*     2.8    66.7    +      -       -      +
    122A  LEU*     3.7    20.6    -      -       +      +
    126A  TYR*     3.2    29.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 109 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    105A  LYS*     2.9    18.3    +      -       -      -
    106A  THR*     3.1     8.5    +      -       -      -
    108A  HIS*     1.3    79.3    -      -       -      +
    110A  ILE*     1.3    65.9    +      -       -      +
    112A  ARG*     3.7    21.0    +      -       -      +
    113A  TYR*     3.1    21.1    +      -       -      +
    171A  TYR*     4.5    10.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 110 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    106A  THR*     2.9    36.6    +      -       +      +
    107A  VAL*     3.4     6.1    -      -       -      +
    109A  SER*     1.3    75.4    -      -       -      +
    111A  LEU*     1.3    65.3    +      -       -      +
    113A  TYR*     3.0    15.8    +      -       -      +
    114A  CYS*     3.3    12.7    +      -       -      -
    141A  TYR*     6.4     0.2    -      -       +      -
    144A  PHE*     4.1    22.7    -      -       +      -
    168A  LEU*     3.7    28.7    -      -       +      -
    171A  TYR*     3.6    47.1    -      -       +      -
    172A  ILE*     4.9     8.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 111 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    107A  VAL*     2.7    27.7    +      -       +      +
    108A  HIS      4.0     1.8    -      -       -      +
    110A  ILE*     1.3    73.1    -      -       -      +
    112A  ARG*     1.3    61.2    +      -       -      +
    114A  CYS*     3.3     3.8    +      -       -      -
    115A  ALA      3.0    19.6    +      -       -      -
    122A  LEU*     3.4    16.7    -      -       +      +
    125A  LEU*     3.3    33.8    -      -       +      +
    126A  TYR*     3.9    28.0    -      -       +      -
    129A  ILE*     5.1     6.3    -      -       +      -
    130A  ALA*     3.8    28.3    -      -       +      -
    144A  PHE*     4.2     9.0    -      -       +      -
    168A  LEU*     4.0    28.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 112 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      2A  SER      5.2     0.2    -      -       -      +
      3A  SER*     3.7    26.8    +      -       -      +
    108A  HIS*     2.8    47.0    +      -       -      +
    109A  SER*     3.7    19.4    +      -       -      +
    110A  ILE      3.1     0.2    -      -       -      -
    111A  LEU*     1.3    73.8    -      -       -      +
    113A  TYR*     1.3    56.6    +      -       -      +
    115A  ALA*     3.9     1.3    -      -       -      +
    116A  GLU*     2.9    57.4    +      -       -      +
    122A  LEU*     3.7    13.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 113 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    109A  SER      3.1    11.6    +      -       -      +
    110A  ILE      3.0     8.7    +      -       -      +
    112A  ARG*     1.3    77.2    -      -       -      +
    114A  CYS*     1.3    65.3    +      -       -      +
    116A  GLU*     4.0     7.3    -      -       -      +
    117A  LYS*     3.0    59.1    +      -       +      +
    167A  GLU*     3.7    22.3    +      -       -      -
    171A  TYR*     3.5    39.7    -      +       +      +
----------------------------------------------------------
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Residues in contact with CYS 114 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    110A  ILE*     3.3    16.3    +      -       -      -
    111A  LEU*     3.6     8.7    -      -       +      +
    112A  ARG      3.2     0.4    -      -       -      -
    113A  TYR*     1.3    81.0    -      -       -      +
    115A  ALA*     1.3    59.4    +      -       -      +
    117A  LYS*     3.1     4.8    +      -       -      -
    118A  PHE*     2.9    39.0    +      -       +      +
    125A  LEU*     3.8    12.6    -      -       +      -
    164A  VAL*     3.9    12.1    -      -       +      -
    167A  GLU*     4.2    12.3    -      -       -      -
    168A  LEU*     4.0    40.4    -      -       -      -
    171A  TYR*     5.4     1.1    -      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 115 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      2A  SER      4.0     8.1    -      -       -      +
    111A  LEU      3.0    14.6    +      -       -      +
    112A  ARG      3.9     3.1    -      -       -      +
    114A  CYS*     1.3    77.7    -      -       -      +
    116A  GLU*     1.3    57.5    +      -       -      +
    119A  GLN*     2.9    23.9    +      -       -      -
    120A  ILE*     2.9    37.4    +      -       -      +
    121A  PRO      4.2     0.2    -      -       -      -
    122A  LEU*     3.7    19.7    -      -       +      +
    125A  LEU*     3.5    16.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 116 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      2A  SER      4.2     6.5    -      -       -      +
      3A  SER*     3.1    28.7    +      -       -      +
    112A  ARG*     2.9    45.5    +      -       -      +
    113A  TYR*     4.1     5.4    -      -       -      +
    115A  ALA*     1.3    73.3    -      -       -      +
    117A  LYS*     1.3    68.4    +      -       -      +
    119A  GLN*     3.1    28.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 117 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    113A  TYR*     3.0    47.0    +      -       +      +
    114A  CYS*     3.1     4.9    +      -       -      +
    116A  GLU*     1.3    80.3    -      -       -      +
    118A  PHE*     1.3    71.4    +      -       +      +
    119A  GLN*     3.2     6.1    +      -       -      +
    167A  GLU*     3.4    38.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 118 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
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    114A  CYS      2.9    21.9    +      -       -      +
    115A  ALA      3.7     0.2    -      -       -      -
    117A  LYS*     1.3    85.0    -      -       +      +
    119A  GLN*     1.3    66.3    +      -       -      +
    120A  ILE*     2.9    26.4    +      -       +      +
    161A  SER*     5.0     2.5    -      -       -      -
    163A  ASP*     3.1    50.5    -      -       +      -
    164A  VAL*     3.9    17.5    -      -       +      -
    167A  GLU*     3.2    44.6    -      -       +      -
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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