Contacts of the helix formed by residues 113 - 139 (chain H) in PDB entry 1F33


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 ASN 113 (chain H).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     55H  ARG*     3.4     8.6    -      -       -      +
     56H  GLY*     5.1     4.2    -      -       -      -
     57H  ALA      5.6     1.4    +      -       -      -
    112H  HIS*     1.3    81.4    -      -       -      +
    114H  VAL*     1.3    66.5    +      -       -      +
    115H  GLN*     2.8    48.1    -      -       -      +
    116H  ASP*     3.2    34.0    +      -       -      +
    117H  HIS*     3.2    11.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 114 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     54H  MET*     4.3    13.4    -      -       +      +
     55H  ARG      3.0    37.9    +      -       -      +
     56H  GLY*     3.8     5.6    -      -       -      +
     57H  ALA      3.4    26.9    -      -       -      +
     58H  ASN*     4.5     1.3    -      -       +      +
     59H  PHE*     4.1    11.2    -      -       -      -
     62H  VAL*     4.2    24.2    -      -       +      -
    112H  HIS      3.3     1.5    +      -       -      -
    113H  ASN*     1.3    73.1    -      -       -      +
    115H  GLN*     1.3    63.8    +      -       +      +
    117H  HIS*     3.2     4.4    +      -       -      +
    118H  LEU*     2.8    45.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 115 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     57H  ALA*     5.3     4.0    +      -       +      +
     58H  ASN*     5.9     3.2    -      -       -      +
    113H  ASN*     2.8    22.6    -      -       -      +
    114H  VAL*     1.3    78.9    -      -       +      +
    116H  ASP*     1.3    61.0    +      -       -      +
    118H  LEU*     3.2    12.4    +      -       -      +
    119H  LYS*     3.0    43.3    +      -       -      +
    165H  ASN      3.2    21.6    +      -       -      -
    166H  ILE*     3.3    13.6    -      -       -      +
    167H  GLU*     2.8    53.3    +      -       +      +
     57L  ALA*     5.8     0.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 116 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    111H  ILE*     4.1    29.1    -      -       +      +
    112H  HIS      4.8     0.3    +      -       -      -
    113H  ASN*     3.2    32.8    +      -       -      +
    115H  GLN*     1.3    77.7    -      -       -      +
    117H  HIS*     1.3    62.5    +      -       -      +
    119H  LYS*     3.2    16.2    +      -       -      +
    120H  GLU*     2.9    26.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with HIS 117 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     49H  GLN*     4.5     4.3    -      -       -      -
     50H  ALA*     3.4    25.0    -      -       +      -
     53H  ASN*     3.3    16.6    +      -       +      -
     54H  MET*     3.7    27.1    -      -       +      -
    107H  TYR*     2.6    33.0    +      +       -      +
    108H  PRO      4.9     1.3    -      -       -      -
    111H  ILE*     3.2    40.3    +      -       +      +
    112H  HIS*     3.4    23.3    -      -       -      -
    113H  ASN      3.2     7.1    +      -       -      -
    114H  VAL      3.2     7.3    +      -       -      +
    116H  ASP*     1.3    78.9    -      -       -      +
    118H  LEU*     1.3    53.1    +      -       -      +
    120H  GLU      3.2     0.3    +      -       -      -
    121H  LEU*     2.7    42.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 118 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     54H  MET*     5.0     1.3    -      -       +      -
     58H  ASN*     5.8     0.4    -      -       -      +
     62H  VAL*     3.8    27.6    -      -       +      -
     65H  MET*     5.1     4.0    -      -       +      -
     66H  LEU*     5.5     0.2    -      -       +      -
    114H  VAL*     2.8    28.5    +      -       +      +
    115H  GLN*     3.4    20.9    -      -       -      +
    116H  ASP      3.2     0.2    -      -       -      -
    117H  HIS*     1.3    77.1    -      -       -      +
    119H  LYS*     1.3    56.1    +      -       -      +
    121H  LEU*     4.5     9.6    -      -       +      -
    122H  ALA*     2.9    25.3    +      -       -      +
    162H  ILE*     3.3    40.8    -      -       +      +
    165H  ASN*     3.6    34.8    -      -       +      +
    166H  ILE*     3.9    10.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 119 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    115H  GLN*     3.0    32.8    +      -       -      +
    116H  ASP*     3.6    14.9    +      -       -      +
    118H  LEU*     1.3    73.9    -      -       -      +
    120H  GLU*     1.3    67.5    +      -       +      +
    122H  ALA*     3.3     3.9    +      -       -      +
    123H  ASP*     3.1    29.6    +      -       -      +
    166H  ILE*     4.0    37.9    -      -       +      -
    167H  GLU      5.7     0.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 120 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    107H  TYR*     3.4    26.5    -      -       +      +
    108H  PRO*     3.9    11.1    -      -       +      +
    111H  ILE*     3.7    21.4    -      -       +      +
    116H  ASP*     2.9    18.7    +      -       +      +
    117H  HIS      3.6     0.2    -      -       -      +
    119H  LYS*     1.3    76.6    -      -       +      +
    121H  LEU*     1.3    61.3    +      -       -      +
    123H  ASP*     3.4    14.1    +      -       -      +
    124H  ARG*     2.9    52.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 121 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     46H  ILE*     3.9    27.4    -      -       +      +
     47H  THR*     4.3     9.6    -      -       -      -
     50H  ALA*     3.6    32.8    -      -       +      -
     54H  MET*     4.7     1.1    -      -       +      -
     66H  LEU*     3.7    31.2    -      -       +      -
    107H  TYR*     4.0     2.9    -      -       +      +
    117H  HIS      2.7    30.3    +      -       -      +
    118H  LEU*     3.7    12.8    -      -       +      +
    120H  GLU*     1.3    72.4    -      -       -      +
    122H  ALA*     1.3    56.3    +      -       -      +
    124H  ARG*     3.1     3.9    +      -       -      -
    125H  TYR*     2.7    50.4    +      -       +      -
    162H  ILE*     4.1    12.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 122 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    118H  LEU      2.9    18.4    +      -       -      +
    119H  LYS*     3.5     9.9    -      -       -      +
    121H  LEU*     1.3    75.0    -      -       -      +
    123H  ASP*     1.3    60.9    +      -       -      +
    125H  TYR*     4.5     0.7    -      -       -      -
    126H  ALA*     2.8    32.6    +      -       -      +
    159H  LEU*     3.4    11.1    -      -       +      +
    162H  ILE*     3.9    15.0    -      -       +      +
    163H  GLU*     4.3    16.4    -      -       +      +
    166H  ILE*     4.2    11.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASP 123 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    119H  LYS*     3.1    14.7    +      -       -      +
    120H  GLU*     3.5    16.7    -      -       -      +
    121H  LEU      3.1     0.8    -      -       -      -
    122H  ALA*     1.3    79.9    -      -       -      +
    124H  ARG*     1.3    69.7    +      -       -      +
    126H  ALA*     3.2     8.0    +      -       -      +
    127H  ILE*     3.1    30.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 124 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     43H  LEU*     3.8    18.2    -      -       +      -
     46H  ILE*     4.2    13.0    -      -       +      +
    104H  LEU*     3.8    19.0    -      -       +      +
    105H  LYS*     2.9    53.9    +      -       -      +
    106H  SER      3.7     3.6    +      -       -      -
    107H  TYR*     2.8    35.7    -      -       -      +
    108H  PRO*     3.5    14.8    -      -       -      +
    120H  GLU*     2.9    41.5    +      -       -      +
    121H  LEU*     3.1     7.0    +      -       -      +
    123H  ASP*     1.3    80.1    -      -       -      +
    125H  TYR*     1.3    63.4    +      -       -      +
    127H  ILE*     3.2    10.2    +      -       -      +
    128H  VAL*     3.1    25.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 125 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     43H  LEU*     3.5    39.5    -      -       +      -
     47H  THR*     2.7    28.5    +      -       +      +
     66H  LEU*     5.4     0.2    -      -       +      -
     69H  PHE*     3.6    16.4    -      +       -      +
     73H  LEU*     3.5    12.1    -      -       +      +
    121H  LEU*     2.7    42.7    +      -       +      +
    122H  ALA      3.8     2.9    -      -       -      +
    124H  ARG*     1.3    72.6    -      -       -      +
    126H  ALA*     1.3    52.4    +      -       -      +
    128H  VAL*     3.4     0.7    +      -       -      +
    129H  ALA*     2.6    40.4    +      -       -      +
    155H  LEU*     4.2     9.7    -      -       +      +
    158H  PHE*     3.7    36.3    -      +       +      -
    159H  LEU*     4.1    15.5    -      -       +      -
    162H  ILE*     3.5    25.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 126 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    122H  ALA      2.8    19.5    +      -       -      +
    123H  ASP*     3.4     8.3    -      -       -      +
    124H  ARG      3.2     0.2    -      -       -      -
    125H  TYR*     1.3    77.1    -      -       -      +
    127H  ILE*     1.3    57.7    +      -       +      +
    129H  ALA*     4.2     0.2    -      -       -      -
    130H  ASN*     2.8    47.9    +      -       -      +
    159H  LEU*     3.9    23.1    -      -       +      +
    163H  GLU*     5.6     1.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 127 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39H  GLN*     4.3    11.4    -      -       -      +
    103H  PRO*     4.4    17.7    -      -       +      +
    104H  LEU*     3.9    24.0    -      -       +      -
    105H  LYS*     5.5     3.1    -      -       +      +
    123H  ASP*     3.1    17.2    +      -       +      +
    124H  ARG*     3.2    14.1    +      -       -      +
    126H  ALA*     1.3    77.5    -      -       +      +
    128H  VAL*     1.3    57.6    +      -       -      +
    130H  ASN*     4.1     2.9    -      -       -      +
    131H  ASP*     3.0    32.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 128 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39H  GLN*     3.4    38.1    -      -       +      +
     40H  PHE*     3.6    27.8    -      -       +      -
     43H  LEU*     4.0    15.7    -      -       +      -
    104H  LEU*     3.9    18.2    -      -       +      -
    124H  ARG      3.1    15.7    +      -       -      +
    125H  TYR      3.9     0.7    -      -       -      +
    127H  ILE*     1.3    71.7    -      -       -      +
    129H  ALA*     1.3    67.1    +      -       -      +
    131H  ASP*     3.8     0.3    -      -       -      +
    132H  VAL*     2.9    24.4    +      -       -      +
    155H  LEU*     3.5    23.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 129 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    125H  TYR      2.6    25.6    +      -       -      +
    126H  ALA*     3.7     5.8    -      -       -      +
    128H  VAL*     1.3    73.0    -      -       -      +
    130H  ASN*     1.3    63.6    +      -       -      +
    132H  VAL*     3.2     9.7    -      -       -      +
    133H  ARG*     3.0    30.7    +      -       -      +
    155H  LEU*     3.8    23.3    -      -       +      +
    156H  ASP*     3.7    17.8    -      -       -      +
    159H  LEU*     4.3    10.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASN 130 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    126H  ALA*     2.8    39.1    +      -       -      +
    127H  ILE*     4.1     3.3    -      -       -      +
    129H  ALA*     1.3    73.6    -      -       -      +
    131H  ASP*     1.3    64.0    +      -       -      +
    133H  ARG*     2.4    36.6    +      -       -      +
    134H  LYS*     3.3    45.2    +      -       -      +
    159H  LEU*     5.2     4.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 131 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     35H  ARG*     2.9    41.0    +      -       -      -
     36H  GLN*     3.6     2.4    -      -       -      +
     39H  GLN*     3.0    26.6    +      -       -      +
    103H  PRO*     5.4     0.7    -      -       -      +
    127H  ILE*     3.0    22.0    +      -       +      +
    128H  VAL      3.8     2.5    -      -       -      +
    130H  ASN*     1.3    73.9    -      -       -      +
    132H  VAL*     1.3    66.5    +      -       -      +
    134H  LYS*     3.0    13.4    +      -       -      +
    135H  ALA      3.0    16.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 132 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     36H  GLN*     3.6    29.6    -      -       -      +
     40H  PHE*     4.3    19.5    -      -       +      -
    128H  VAL      2.9    19.0    +      -       -      +
    129H  ALA*     3.2    16.6    -      -       -      +
    131H  ASP*     1.3    74.7    -      -       -      +
    133H  ARG*     1.3    67.7    +      -       -      +
    135H  ALA*     3.1    10.3    +      -       -      +
    136H  ILE*     3.3    13.2    +      -       -      +
    148H  LEU*     3.8    35.8    -      -       +      +
    151H  ALA*     4.7     1.8    -      -       +      -
    152H  SER*     4.0    20.6    -      -       -      +
    155H  LEU*     4.8     2.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 133 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    129H  ALA*     3.0    21.1    +      -       -      +
    130H  ASN*     2.4    37.7    +      -       -      +
    131H  ASP      3.1     0.2    -      -       -      -
    132H  VAL*     1.3    77.2    -      -       -      +
    134H  LYS*     1.3    66.9    +      -       +      +
    136H  ILE*     3.4    25.0    -      -       +      +
    137H  GLY      4.4     0.7    +      -       -      -
    152H  SER*     3.7    17.0    -      -       -      +
    156H  ASP*     2.6    44.6    +      -       -      -
    159H  LEU*     6.2     0.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 134 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    130H  ASN*     3.3    36.1    +      -       -      +
    131H  ASP*     3.0     9.5    +      -       -      +
    133H  ARG*     1.3    81.9    -      -       +      +
    135H  ALA*     1.3    64.9    +      -       -      +
    136H  ILE      3.0     3.7    +      -       -      -
    137H  GLY*     3.1    12.0    +      -       -      +
    138H  GLU*     3.2    15.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 135 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     32H  LEU*     3.9    19.8    -      -       +      +
     35H  ARG*     4.3     3.6    -      -       -      +
     36H  GLN*     3.6    23.3    -      -       -      +
    131H  ASP*     3.0     9.3    +      -       -      +
    132H  VAL*     3.1     9.4    +      -       -      +
    134H  LYS*     1.3    76.1    -      -       -      +
    136H  ILE*     1.3    57.1    -      -       -      +
    138H  GLU*     3.5    13.1    -      -       -      +
    139H  ALA*     2.8    31.5    +      -       -      +
    148H  LEU*     3.7    13.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 136 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    132H  VAL      3.4     8.7    -      -       -      +
    133H  ARG*     3.4    21.3    -      -       +      +
    134H  LYS      3.0     0.4    -      -       -      -
    135H  ALA*     1.3    78.1    -      -       -      +
    137H  GLY*     1.3    63.4    +      -       -      +
    139H  ALA*     3.2    21.1    +      -       -      +
    145H  ALA*     4.0    14.4    -      -       +      +
    148H  LEU*     3.9    22.0    -      -       +      +
    149H  THR*     3.5    41.5    -      -       +      +
    152H  SER*     3.7    20.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 137 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    133H  ARG      4.4     0.8    +      -       -      -
    134H  LYS      3.1     6.8    +      -       -      -
    136H  ILE*     1.3    81.0    -      -       -      +
    138H  GLU*     1.3    60.4    -      -       -      +
    139H  ALA      3.4     5.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 138 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     32H  LEU*     3.6    30.9    -      -       +      +
     35H  ARG*     3.9    12.3    +      -       -      -
    134H  LYS*     3.2    13.1    +      -       -      +
    135H  ALA*     3.5    11.8    +      -       -      +
    137H  GLY*     1.3    77.0    -      -       -      +
    139H  ALA*     1.3    61.5    +      -       -      +
    140H  LYS*     3.5    11.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 139 (chain H). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     32H  LEU*     4.0    15.0    -      -       +      -
    135H  ALA      2.8    10.8    +      -       -      +
    136H  ILE      3.4    17.3    -      -       -      +
    137H  GLY      3.2     5.0    -      -       -      +
    138H  GLU*     1.3    77.2    -      -       -      +
    140H  LYS*     1.3    64.0    +      -       -      +
    141H  ASP      4.4     1.3    -      -       -      +
    144H  THR*     4.4     6.7    -      -       +      -
    145H  ALA*     4.0    30.2    -      -       -      +
    148H  LEU*     4.1     5.6    -      -       +      -
----------------------------------------------------------
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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