Contacts of the helix formed by residues 90 - 115 (chain A) in PDB entry 4GTU


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 GLU 90 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     88A  GLU      3.9     1.4    +      -       -      -
     89A  THR*     1.3    72.1    -      -       -      +
     91A  GLU*     1.3    60.4    +      -       -      +
     93A  LYS*     3.4    18.2    +      -       -      +
     94A  ILE*     3.3    24.8    +      -       +      +
     67B  HIS*     5.7     4.0    -      -       -      +
     78B  TYR*     3.5    26.7    -      -       +      -
     81B  ARG*     3.2    38.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 91 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     89A  THR*     3.1    19.4    +      -       -      +
     90A  GLU*     1.3    77.6    -      -       -      +
     92A  GLU*     1.3    70.0    +      -       +      +
     94A  ILE*     3.4    13.0    +      -       -      +
     95A  ARG*     3.2    27.9    +      -       -      +
----------------------------------------------------------
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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
----------------------------------------------------------
     87A  GLY*     3.9     8.1    -      -       -      -
     88A  GLU*     3.5    14.1    +      -       -      +
     89A  THR*     2.6    54.3    +      -       -      +
     91A  GLU*     1.3    76.0    -      -       +      +
     93A  LYS*     1.3    51.6    +      -       -      +
     95A  ARG*     2.9     6.0    +      -       -      +
     96A  VAL*     2.8    40.5    +      -       -      +
    148A  VAL*     3.7    31.9    -      -       +      +
    149A  GLY*     5.2     0.3    -      -       -      -
    150A  ASP*     5.1     4.0    +      -       -      +
    151A  LYS*     3.7    32.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 93 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     87A  GLY*     3.4    29.8    -      -       -      +
     88A  GLU      3.8    13.7    -      -       -      -
     89A  THR      2.8    12.4    +      -       -      +
     90A  GLU*     3.5    24.1    +      -       -      +
     91A  GLU      3.3     0.2    -      -       -      -
     92A  GLU*     1.3    76.8    -      -       -      +
     94A  ILE*     1.3    55.8    +      -       -      +
     96A  VAL*     3.3     4.4    +      -       -      +
     97A  ASP*     3.0    34.1    +      -       -      +
     81B  ARG*     3.4    39.2    -      -       -      +
----------------------------------------------------------
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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
----------------------------------------------------------
     90A  GLU*     3.3    23.9    +      -       +      +
     91A  GLU*     3.7    11.7    -      -       -      +
     92A  GLU      3.2     0.6    -      -       -      -
     93A  LYS*     1.3    73.9    -      -       +      +
     95A  ARG*     1.3    67.4    +      -       +      +
     97A  ASP*     3.3     6.5    +      -       +      +
     98A  ILE*     3.0    32.7    +      -       +      +
     67B  HIS*     3.8    21.3    -      -       +      +
     69B  ILE*     3.2    35.7    -      -       +      -
     74B  ALA*     6.3     0.2    -      -       +      -
     78B  TYR*     3.7    34.5    -      -       +      -
     81B  ARG*     5.8     1.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 95 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     91A  GLU*     3.2    16.3    +      -       -      +
     92A  GLU*     2.9    10.1    +      -       -      +
     94A  ILE*     1.3    77.8    -      -       +      +
     96A  VAL*     1.3    58.0    +      -       -      +
     98A  ILE*     4.7     0.4    -      -       -      -
     99A  LEU*     3.0    33.6    +      -       -      +
    139A  GLN      5.5     0.2    +      -       -      -
    140A  PHE*     2.9    64.5    +      -       +      +
    144A  ARG*     2.7    39.9    -      -       -      +
    147A  PHE      3.0    15.2    +      -       -      -
    148A  VAL*     3.2    36.6    -      -       +      +
     55B  ASP*     4.8     6.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 96 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     86A  CYS*     4.6     1.1    -      -       +      -
     87A  GLY*     3.6    27.8    -      -       -      +
     92A  GLU      2.8    19.8    +      -       -      +
     93A  LYS*     3.6     6.7    -      -       -      +
     95A  ARG*     1.3    74.9    -      -       -      +
     97A  ASP*     1.3    67.4    +      -       -      +
    100A  GLU*     3.1    29.4    +      -       -      +
    148A  VAL*     3.8    22.2    -      -       +      -
    153A  THR*     4.6     4.7    -      -       +      +
    154A  PHE*     3.5    37.0    -      -       +      -
    155A  VAL*     3.5     9.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASP 97 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     93A  LYS      3.0    19.0    +      -       -      +
     94A  ILE*     3.7     6.1    -      -       -      +
     96A  VAL*     1.3    79.9    -      -       -      +
     98A  ILE*     1.3    62.7    +      -       -      +
    100A  GLU*     4.8     4.3    -      -       -      +
    101A  ASN*     3.0    36.0    +      -       -      +
     73B  ASN      5.4     0.2    -      -       -      -
     74B  ALA*     3.6    27.2    -      -       +      +
     77B  CYS*     3.4    17.8    -      -       -      +
     78B  TYR*     5.3     0.2    -      -       -      +
     81B  ARG*     3.0    38.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 98 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     94A  ILE*     3.0    19.8    +      -       +      +
     95A  ARG*     3.9     3.8    -      -       -      +
     97A  ASP*     1.3    76.8    -      -       -      +
     99A  LEU*     1.3    57.7    +      -       -      +
    101A  ASN*     4.1     0.9    -      -       -      +
    102A  GLN*     2.9    35.6    +      -       +      +
    140A  PHE*     4.2    11.7    -      -       +      -
     55B  ASP*     5.1     3.4    -      -       +      +
     56B  PHE*     3.5    34.5    -      -       +      -
     69B  ILE*     3.6    19.7    -      -       +      -
     70B  THR*     3.4    32.5    -      -       -      +
     71B  GLN*     4.4     3.5    -      -       +      +
     74B  ALA*     3.4    25.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 99 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     95A  ARG      3.0    18.8    +      -       -      +
     96A  VAL      4.3     0.2    -      -       -      +
     98A  ILE*     1.3    74.4    -      -       -      +
    100A  GLU*     1.3    57.7    +      -       -      +
    102A  GLN*     3.2     1.0    +      -       +      +
    103A  ALA*     2.7    45.8    +      -       +      +
    137A  PHE*     4.2    17.0    -      -       +      -
    140A  PHE*     3.8    15.2    -      -       +      -
    147A  PHE*     3.7    36.3    -      -       +      -
    155A  VAL*     3.3    40.8    -      -       +      +
    158A  LEU*     5.3     0.2    -      -       +      -
    159A  ALA*     3.8    16.6    -      -       +      -
     56B  PHE*     4.3     9.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 100 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     73A  ASN*     3.5    31.9    +      -       -      +
     77A  CYS*     3.8    16.5    -      -       -      -
     96A  VAL*     3.1    18.5    +      -       -      +
     97A  ASP*     4.6     4.5    -      -       -      +
     99A  LEU*     1.3    77.2    -      -       -      +
    101A  ASN*     1.3    78.5    +      -       -      +
    103A  ALA*     3.4     3.1    +      -       -      +
    104A  MET*     3.0    28.2    +      -       -      +
    154A  PHE*     3.3    25.0    -      -       +      -
    155A  VAL*     3.9    10.2    -      -       +      +
    158A  LEU*     3.6    22.6    -      -       +      +
    100B  GLU*     4.1    13.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 101 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     73A  ASN*     5.8     3.5    -      -       -      +
     97A  ASP*     3.0    21.7    +      -       -      +
     99A  LEU      3.3     0.2    -      -       -      -
    100A  GLU*     1.3   100.8    +      -       -      +
    102A  GLN*     1.3    55.9    +      -       -      +
    104A  MET*     3.0     9.0    +      -       -      +
    105A  ASP*     2.7    35.2    +      -       -      +
     71B  GLN*     2.9    34.4    -      -       +      +
     73B  ASN*     2.9    44.1    +      -       -      +
     74B  ALA      4.7     1.1    -      -       -      +
----------------------------------------------------------
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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  ILE*     2.9    22.3    +      -       -      +
     99A  LEU*     3.7     5.2    -      -       -      +
    101A  ASN*     1.3    75.5    -      -       -      +
    103A  ALA*     1.3    62.4    +      -       -      +
    105A  ASP*     3.0    19.8    +      -       -      +
    106A  VAL*     3.0    27.9    +      -       -      +
    137A  PHE*     4.5     9.7    -      -       +      -
     56B  PHE*     3.7    54.3    -      -       +      +
     58B  ASN*     6.0     3.7    -      -       -      +
     70B  THR*     5.2     2.8    -      -       -      +
     71B  GLN*     3.2    25.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 103 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     99A  LEU*     2.7    34.9    +      -       +      +
    100A  GLU      3.7     0.4    -      -       -      +
    102A  GLN*     1.3    73.1    -      -       -      +
    104A  MET*     1.3    57.0    +      -       -      +
    106A  VAL*     3.3    11.7    -      -       -      +
    107A  SER*     3.2    28.8    +      -       -      -
    137A  PHE*     4.6     7.4    -      -       +      -
    158A  LEU*     3.6    25.4    -      -       +      -
    159A  ALA*     4.7     5.6    -      -       -      +
    162A  VAL*     3.4    13.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with MET 104 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12A  LEU*     4.5    13.0    -      -       +      -
     72A  SER*     4.3    17.3    -      -       -      +
     73A  ASN*     3.2    44.2    -      -       -      +
     76A  LEU*     5.1     2.9    -      -       +      -
    100A  GLU      3.0    12.4    +      -       -      +
    101A  ASN*     3.3    12.6    -      -       -      +
    103A  ALA*     1.3    76.5    -      -       -      +
    105A  ASP*     1.3    62.4    +      -       -      +
    107A  SER*     2.8    26.5    +      -       -      -
    108A  ASN*     3.2    24.0    +      -       -      +
    158A  LEU*     4.4    18.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASP 105 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    101A  ASN      2.7    15.4    +      -       -      +
    102A  GLN*     3.0    25.5    +      -       -      +
    104A  MET*     1.3    76.3    -      -       -      +
    106A  VAL*     1.3    57.8    +      -       -      +
    108A  ASN*     3.5     3.5    +      -       -      +
    109A  GLN*     3.0    56.5    +      -       -      +
    112A  ARG*     4.6     1.8    +      -       -      +
     71B  GLN*     3.4    23.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 106 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    102A  GLN*     3.0    16.2    +      -       -      +
    103A  ALA*     3.3    20.6    -      -       -      +
    105A  ASP*     1.3    77.0    +      -       -      +
    107A  SER*     1.3    59.9    +      -       -      +
    109A  GLN*     3.1    13.1    +      -       -      +
    110A  LEU*     2.9    27.5    +      -       -      +
    126A  TYR*     3.3    21.3    -      -       -      +
    130A  LEU*     6.3     0.2    -      -       +      -
    133A  MET*     5.2     9.0    -      -       +      -
    134A  MET*     6.3     1.1    -      -       -      -
    137A  PHE*     3.8    22.4    -      -       +      -
    162A  VAL*     3.5    17.3    -      -       +      -
    166A  HIS*     3.7    16.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with SER 107 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12A  LEU*     4.8     7.9    -      -       -      +
    103A  ALA      3.2    16.8    +      -       -      -
    104A  MET*     2.8    30.2    +      -       -      -
    106A  VAL*     1.3    75.6    -      -       -      +
    108A  ASN*     1.3    69.6    +      -       -      +
    110A  LEU*     3.3     7.8    +      -       -      +
    111A  ALA*     2.9    25.7    +      -       -      +
    158A  LEU*     6.1     0.9    -      -       -      -
    161A  ASP*     6.0     1.1    -      -       -      -
    162A  VAL*     4.0    18.2    -      -       -      -
    166A  HIS*     5.8     0.4    -      -       -      -
    208A  TYR*     4.6     2.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with ASN 108 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12A  LEU*     4.4    14.8    -      -       -      +
    104A  MET*     3.2    24.3    +      -       -      +
    105A  ASP*     4.0     1.3    -      -       -      +
    107A  SER*     1.3    89.2    +      -       -      +
    109A  GLN*     1.3    55.3    +      -       -      +
    111A  ALA*     3.0    11.9    +      -       -      +
    112A  ARG*     2.6    66.6    +      -       -      +
    112B  ARG*     4.6     8.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLN 109 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    105A  ASP*     3.0    41.3    +      -       -      +
    106A  VAL*     3.1    15.6    +      -       -      +
    108A  ASN*     1.3    75.6    -      -       -      +
    110A  LEU*     1.3    63.6    +      -       -      +
    112A  ARG*     3.3    24.7    +      -       -      +
    113A  VAL*     3.2    19.3    -      -       -      +
    126A  TYR*     4.5    12.3    -      -       +      -
    133A  MET*     4.2    19.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 110 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    106A  VAL      2.9    12.0    +      -       -      +
    107A  SER*     3.7     9.9    -      -       -      +
    109A  GLN*     1.3    75.9    -      -       -      +
    111A  ALA*     1.3    58.2    +      -       -      +
    113A  VAL*     3.1    14.0    +      -       +      +
    114A  CYS*     3.0    29.7    +      -       -      +
    126A  TYR*     3.9    29.3    +      -       +      +
    165A  LEU*     3.9    26.0    -      -       +      +
    166A  HIS*     3.8    22.9    -      -       +      +
    169A  PHE*     4.1    35.9    -      -       +      -
    208A  TYR*     3.1    23.8    -      -       +      +
    214A  TRP*     5.4     0.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 111 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    107A  SER      2.9    15.1    +      -       -      +
    108A  ASN*     3.1    23.6    -      -       +      +
    110A  LEU*     1.3    75.9    -      -       -      +
    112A  ARG*     1.3    62.3    +      -       -      +
    114A  CYS      4.1     0.2    -      -       -      -
    115A  TYR*     3.0    43.7    +      -       +      +
    208A  TYR*     3.8    21.0    +      -       +      -
----------------------------------------------------------
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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
----------------------------------------------------------
    105A  ASP*     4.6     2.0    +      -       -      +
    108A  ASN*     2.6    61.2    +      -       -      +
    109A  GLN*     3.3    25.0    -      -       -      +
    111A  ALA*     1.3    75.2    -      -       -      +
    113A  VAL*     1.3    64.7    +      -       +      +
    115A  TYR*     3.3     3.5    +      -       -      +
    116A  SER*     3.0    27.2    +      -       -      -
    122A  LEU*     5.9     0.2    -      -       -      -
    108B  ASN*     4.5    12.2    -      -       -      +
    112B  ARG*     4.1    33.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 113 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    109A  GLN      3.2    17.5    -      -       -      +
    110A  LEU*     3.1    10.5    +      -       +      +
    112A  ARG*     1.3    77.8    -      -       +      +
    114A  CYS*     1.3    58.9    +      -       -      +
    115A  TYR      3.0     4.2    +      -       -      -
    116A  SER*     2.7    28.0    +      -       -      +
    119A  PHE*     3.9    26.8    -      -       +      -
    122A  LEU*     4.5    14.6    -      -       +      +
    123A  LYS*     4.4    22.2    -      -       -      +
    126A  TYR*     4.2    26.9    -      -       +      -
    169A  PHE*     5.1     5.8    -      -       +      -
----------------------------------------------------------
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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  LEU*     3.0    15.0    +      -       -      +
    113A  VAL*     1.3    71.2    -      -       -      +
    115A  TYR*     1.3    62.1    +      -       -      +
    119A  PHE*     3.5    11.0    -      -       -      -
    169A  PHE*     4.4     5.2    -      -       -      -
    208A  TYR*     3.7    27.1    -      -       +      -
    212A  ALA*     3.6     0.3    -      -       -      -
    213A  VAL*     2.9    37.9    +      -       -      +
    214A  TRP*     3.1    61.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 115 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    111A  ALA*     3.0    31.1    +      -       +      +
    112A  ARG*     3.3     4.2    +      -       -      +
    113A  VAL      3.0     1.2    -      -       -      -
    114A  CYS*     1.3    87.0    -      -       -      +
    116A  SER*     1.3    61.1    +      -       -      +
    117A  PRO*     4.0     3.8    -      -       -      +
    208A  TYR*     3.9    16.4    -      +       -      -
    209A  THR*     3.0    39.5    +      -       -      +
    211A  VAL*     4.6     6.3    -      -       +      -
    212A  ALA*     3.3    29.6    -      -       +      -
    213A  VAL*     5.0     3.1    -      -       -      +
----------------------------------------------------------
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A short description of the analytical approach
The contact analysis used in this page is based upon the approach developed in: Sobolev V., Wade R.C., Vriend G. and Edelman M. PROTEINS (1996) 25, 120-129. Contact legitimacy depends on the hydrophobic-hydrophilic properties of the contacting atoms. In order to define it, for each inter-atomic contact, eight atom classes have been introduced:


   I  Hydrophilic      - N and O that can donate and accept hydrogen bonds
                         (e.g., oxygen of hydroxyl group of Ser. or Thr)
  II  Acceptor         - N or O that can only accept a hydrogen bond
 III  Donor            - N that can only donate a hydrogen bond
  IV  Hydrophobic      - Cl, Br, I and all C atoms that are not in
                         aromatic rings and do not have a covalent bond to
                         a N or O atom
   V  Aromatic         - C in aromatic rings irrespective of any other 
                         bonds formed by the atom
  VI  Neutral          - C atoms that have a covalent bond to at least one
                         atom of class I or two or more atoms from class II
                         or III; atoms; S, F, P, and metal atoms in all cases
 VII  Neutral-donor    - C atoms that have a covalent bond with only one
                         atom of class III
VIII  Neutral-acceptor - C atoms that have a covalent bond with only 
                         one atom of class II
For each pair of contacts the state of legitimacy is shown below:

Legend:
+, legitimate
-, illegitimate
------------------------------------------------------------
  Atomic class           I  II  III   IV   V   VI  VII  VIII
------------------------------------------------------------
   I  (Hydrophilic)      +   +    +    -   +   +    +    +
  II  (Acceptor)         +   -    +    -   +   +    +    -
 III  (Donor)            +   +    -    -   +   +    -    +
  IV  (Hydrophobic)      -   -    -    +   +   +    +    +
   V  (Aromatic)         +   +    +    +   +   +    +    +
  VI  (Neutral)          +   +    +    +   +   +    +    +
 VII  (Neutral-donor)    +   +    -    +   +   +    -    +
VIII  (Neutral-acceptor) +   -    +    +   +   +    +    -
------------------------------------------------------------
Warning!
Atom classes for heterogroups are automatically assigned based on the atomic coordinates. However, in three cases (see below) the automatic assignment is currently ambiguous. In these cases, the user is advised to manually analyse the full list of contacts using LPC software.
1. Carbon atoms belonging to a 4-, 5- or 6-member ring are 
   considered "aromatic" (Class V) if the ring is approximately
   planar, and "hydrophobic" (Class IV) or "neutral" (Classes
   VI, VII, VIII) if the ring is non-planar.
2. The oxygen atom of a carbonyl or hydroxy group is considered
   "hydroxy" (Class I) if the CO bond is longer than 1.29 Å, and
   "carbonyl" (Class II) if shorter.
3. All nitrogen atoms are considered "hydrophilic" (Class I).

Please E-mail any questions and/or suggestions concerning this page to Vladimir.Sobolev@weizmann.ac.il