Contacts of the helix formed by residues 106 - 130 (chain E) in PDB entry 6AHU


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 THR 106 (chain E).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     25A    U      4.9     1.1    -      -       -      +
     26A    G      4.3    17.6    -      -       -      +
    271A    U      3.6     7.8    +      -       -      -
    272A    U      2.4    34.1    +      -       -      -
    274A    A      4.3    16.2    -      -       -      -
    275A    A      4.3    15.0    -      -       -      +
      8E  TYR*     4.8     0.2    -      -       -      -
    103E  VAL*     3.8     8.3    -      -       +      -
    104E  GLY      3.4    15.0    +      -       -      +
    105E  GLY*     1.3    75.8    -      -       -      +
    107E  ILE*     1.3    63.7    +      -       -      +
    108E  ARG      3.1     2.7    +      -       -      -
    109E  THR*     3.3    23.2    +      -       +      +
    110E  CYS*     3.2    15.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 107 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    272A    U      5.1     3.3    +      -       -      -
    273A    C      3.3    53.2    -      -       +      +
    274A    A      5.3     1.5    -      -       -      +
    119B  LEU*     4.6    14.1    -      -       +      -
      8E  TYR*     3.6    45.8    -      -       +      -
     56E  ARG*     6.4     0.7    -      -       +      -
     66E  LEU*     4.3    15.0    -      -       +      -
    105E  GLY      3.4     0.4    +      -       -      -
    106E  THR*     1.3    70.7    -      -       -      +
    108E  ARG*     1.3    58.0    +      -       +      +
    110E  CYS*     3.2     9.0    +      -       +      +
    111E  GLN*     2.9    41.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 108 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    272A    U      3.3    81.0    -      -       -      +
    273A    C      4.0    11.2    +      -       -      +
    119B  LEU*     6.2     2.2    -      -       +      -
    120B  LYS*     3.8    19.8    +      -       +      +
    123B  THR*     3.4    41.7    +      -       +      +
    124B  GLN*     3.4    36.4    -      -       -      +
    127B  SER*     5.7     2.0    -      -       -      +
    106E  THR      3.1     1.0    +      -       -      -
    107E  ILE*     1.3    76.3    -      -       +      +
    109E  THR*     1.3    58.1    +      -       -      +
    111E  GLN*     3.1     9.4    +      -       -      +
    112E  LYS*     3.0    41.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 109 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     26A    G      3.4    31.0    +      -       -      +
     27A    G      3.9    17.2    +      -       -      -
    272A    U      5.2     0.4    -      -       -      -
    103E  VAL*     4.3     5.6    -      -       +      +
    106E  THR*     3.3    32.1    +      -       +      +
    108E  ARG*     1.3    75.2    -      -       -      +
    110E  CYS*     1.3    60.9    +      -       -      +
    111E  GLN      3.3     0.2    -      -       -      -
    112E  LYS*     3.6    24.4    -      -       -      +
    113E  PHE*     3.2    24.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with CYS 110 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      8E  TYR*     4.7     4.3    -      -       -      -
     10E  LEU*     3.9    34.0    -      -       -      +
     66E  LEU*     4.1    17.5    -      -       -      -
    103E  VAL*     3.8    33.2    -      -       +      -
    105E  GLY      4.6     1.3    -      -       -      +
    106E  THR      3.2    12.7    +      -       -      +
    107E  ILE*     3.2    17.2    +      -       +      +
    109E  THR*     1.3    79.3    -      -       -      +
    111E  GLN*     1.3    66.4    +      -       -      +
    113E  PHE*     3.8     1.8    +      -       -      +
    114E  LEU*     3.6    17.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 111 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    115B  ILE*     6.3     0.4    -      -       -      +
    116B  SER*     2.9    46.9    +      -       -      +
    119B  LEU*     4.2    30.6    -      -       +      +
    120B  LYS*     5.4     4.3    -      -       +      -
     10E  LEU*     5.6     1.2    -      -       -      +
     57E  TYR*     4.6    25.0    -      -       -      -
     66E  LEU*     4.9     7.4    -      -       -      +
    107E  ILE*     2.9    23.5    +      -       +      +
    108E  ARG*     3.6     8.1    -      -       -      +
    110E  CYS*     1.3    84.7    -      -       -      +
    112E  LYS*     1.3    64.6    +      -       -      +
    114E  LEU*     3.4    17.2    +      -       -      +
    115E  ILE*     3.2    27.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 112 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27A    G      4.4    13.4    +      -       -      +
    120B  LYS*     3.7    31.0    -      -       -      +
    124B  GLN*     5.4     7.4    -      -       -      +
    108E  ARG*     3.0    29.8    +      -       -      +
    109E  THR*     3.7    24.2    -      -       -      +
    110E  CYS      3.3     0.4    -      -       -      -
    111E  GLN*     1.3    77.0    -      -       -      +
    113E  PHE*     1.3    59.1    +      -       -      +
    115E  ILE*     3.2    14.9    +      -       +      +
    116E  GLN*     2.4    37.2    +      -       -      +
     61G  ARG*     3.2    42.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 113 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     10E  LEU*     4.3    10.3    -      -       +      -
    100E  THR*     3.7    30.1    -      -       +      -
    101E  LEU*     3.7    49.1    -      -       +      -
    103E  VAL*     5.5     4.0    -      -       +      -
    109E  THR      3.2    14.7    +      -       -      +
    110E  CYS*     4.2     6.5    -      -       -      +
    111E  GLN      3.4     0.2    -      -       -      -
    112E  LYS*     1.3    77.0    -      -       -      +
    114E  LEU*     1.3    57.9    +      -       -      +
    115E  ILE      3.3     0.2    -      -       -      -
    116E  GLN*     3.6    10.0    +      -       +      +
    117E  TYR*     3.0    42.1    +      +       +      +
    120E  ARG*     6.3     0.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 114 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    112B  ALA*     3.9    21.5    -      -       +      +
    116B  SER*     3.4    22.7    -      -       -      +
     10E  LEU*     4.9    11.7    -      -       +      -
     57E  TYR*     3.9    21.8    -      -       +      +
     62E  THR*     6.5     0.2    -      -       +      -
     64E  ILE*     3.8    37.9    -      -       +      -
    110E  CYS      3.6    10.4    +      -       -      +
    111E  GLN*     3.4    22.1    +      -       -      +
    112E  LYS      3.2     0.4    -      -       -      -
    113E  PHE*     1.3    78.4    -      -       -      +
    115E  ILE*     1.3    59.3    +      -       -      +
    117E  TYR*     4.0     8.2    -      -       +      +
    118E  ASN*     3.1    29.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 115 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    112B  ALA      5.2     0.2    -      -       -      +
    113B  ALA*     5.0    16.2    -      -       +      +
    116B  SER*     4.0    24.2    -      -       -      +
    117B  ALA*     4.2    10.5    -      -       +      +
    120B  LYS*     3.9    27.1    -      -       +      -
    111E  GLN      3.2    15.2    +      -       -      +
    112E  LYS*     3.2    11.5    +      -       +      +
    114E  LEU*     1.3    75.9    -      -       -      +
    116E  GLN*     1.3    67.0    +      -       -      +
    118E  ASN*     3.1     5.8    +      -       -      +
    119E  ARG*     2.9    64.5    +      -       +      +
     59G  GLY      5.3     7.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 116 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    112E  LYS*     2.4    42.5    +      -       -      +
    113E  PHE*     4.1    11.4    -      -       +      +
    115E  ILE*     1.3    91.7    -      -       -      +
    117E  TYR*     1.3    61.0    +      -       -      +
    119E  ARG*     4.2     8.8    +      -       -      +
    120E  ARG*     3.3    40.6    +      -       -      +
     57G  ASP*     3.4    35.4    -      -       +      +
     58G  GLY*     5.3     0.3    -      -       -      -
     59G  GLY      4.9     3.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 117 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12E  GLU*     2.6    41.7    +      -       -      -
     64E  ILE*     5.0    13.5    -      -       +      -
    100E  THR*     4.8    16.4    -      -       +      -
    113E  PHE*     3.0    35.1    +      +       +      +
    114E  LEU*     4.0     9.4    -      -       +      +
    115E  ILE      3.2     0.2    -      -       -      -
    116E  GLN*     1.3    77.3    -      -       -      +
    118E  ASN*     1.3    62.2    +      -       -      +
    120E  ARG*     3.7     7.0    +      -       +      +
    121E  GLN*     3.4    34.1    +      -       -      +
     27I  HIS*     3.3     2.8    +      -       -      -
     65I  GLN*     2.7    51.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 118 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    109B  GLN*     2.5    36.1    +      -       -      +
    112B  ALA*     3.5    12.5    -      -       -      +
    113B  ALA*     3.2    28.5    -      -       +      +
    114E  LEU*     3.1    21.1    +      -       +      +
    115E  ILE*     3.1     6.9    +      -       -      +
    117E  TYR*     1.3    77.7    -      -       +      +
    119E  ARG*     1.3    63.7    +      -       -      +
    121E  GLN*     3.3    13.7    +      -       -      +
    122E  LEU*     3.3    34.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 119 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    113B  ALA*     5.8     6.3    -      -       +      +
    115E  ILE*     2.9    43.2    +      -       +      +
    116E  GLN*     4.2     8.8    +      -       -      +
    118E  ASN*     1.3    77.9    -      -       +      +
    120E  ARG*     1.3    63.1    +      -       +      +
    121E  GLN      3.4     0.7    +      -       -      -
    122E  LEU*     3.7     3.4    +      -       -      +
    123E  LEU*     3.3    31.9    +      -       +      +
    145E  SER*     6.0     4.6    -      -       -      -
     57G  ASP*     2.9    42.8    +      -       -      +
     59G  GLY*     3.4    30.5    +      -       -      +
     66G  CYS*     3.5    19.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 120 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    113E  PHE*     6.3     0.4    -      -       -      -
    116E  GLN*     3.3    27.9    +      -       -      +
    117E  TYR*     4.2     7.0    -      -       +      +
    118E  ASN      3.3     0.4    -      -       -      -
    119E  ARG*     1.3    78.2    -      -       +      +
    121E  GLN*     1.3    61.4    +      -       -      +
    123E  LEU*     4.1     9.5    -      -       +      +
    124E  ILE*     3.4    33.5    +      -       +      +
     53G  GLN*     5.2    10.5    -      -       -      +
     57G  ASP*     4.9    15.7    +      -       -      +
     65I  GLN*     3.9    25.2    +      -       +      +
     66I  GLY*     3.4    25.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLN 121 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    109B  GLN*     3.1    36.7    +      -       -      +
     12E  GLU*     5.1     4.4    +      -       -      +
    117E  TYR*     3.4    33.4    +      -       -      +
    118E  ASN*     3.3    11.7    +      -       -      +
    119E  ARG      3.2     1.0    -      -       -      -
    120E  ARG*     1.3    79.6    -      -       -      +
    122E  LEU*     1.3    62.6    +      -       +      +
    124E  ILE*     3.8     4.6    +      -       -      +
    125E  LEU*     3.3    27.7    +      -       +      +
     27I  HIS*     5.0    11.5    -      -       +      -
     65I  GLN*     4.8    14.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 122 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    106B  THR*     5.2     4.7    -      -       +      -
    109B  GLN*     3.3    34.8    -      -       +      +
    110B  ALA*     5.4     0.4    -      -       -      +
    118E  ASN*     3.3    38.9    +      -       -      +
    119E  ARG*     3.7     4.7    +      -       -      +
    120E  ARG      3.5     0.2    -      -       -      -
    121E  GLN*     1.3    77.9    -      -       +      +
    123E  LEU*     1.3    64.4    +      -       +      +
    125E  LEU*     3.6    15.8    +      -       +      +
    126E  LEU*     3.3    21.8    +      -       -      +
    138E  ILE*     3.8    26.5    -      -       +      +
    141E  SER*     3.6    30.1    -      -       -      +
    142E  VAL*     6.2     0.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 123 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    119E  ARG*     3.3    24.5    +      -       +      +
    120E  ARG*     4.0     9.4    +      -       +      +
    121E  GLN      3.4     0.4    -      -       -      -
    122E  LEU*     1.3    79.5    -      -       +      +
    124E  ILE*     1.3    65.1    +      -       +      +
    126E  LEU*     3.4    32.1    +      -       +      +
     57G  ASP*     5.7     4.9    -      -       -      +
     92G  SER*     3.5    31.9    -      -       -      +
     93G  PHE*     3.2    20.4    -      -       +      -
     94G  GLY*     4.4    12.8    -      -       -      +
    139G  PRO*     5.9     1.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 124 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    120E  ARG*     3.4    23.1    +      -       +      +
    121E  GLN*     4.3     4.7    -      -       -      +
    123E  LEU*     1.3    78.1    -      -       +      +
    125E  LEU*     1.3    60.7    +      -       -      +
    126E  LEU      3.1     1.8    +      -       -      -
    127E  GLN      3.9     2.1    +      -       -      -
    128E  ASN*     3.0    42.7    +      -       -      +
     93G  PHE*     3.9    17.1    -      -       +      -
     63I  ILE*     3.8    26.7    -      -       +      +
     64I  VAL      3.8    22.9    -      -       -      +
     65I  GLN*     3.9    18.6    -      -       +      -
     68I  SER*     5.8     3.1    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 125 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    106B  THR*     5.3     1.8    -      -       -      +
    109B  GLN*     4.5    18.4    -      -       -      +
    121E  GLN*     3.3    22.6    +      -       +      +
    122E  LEU*     3.7     8.3    -      -       +      +
    123E  LEU      3.2     0.6    -      -       -      -
    124E  ILE*     1.3    76.7    -      -       -      +
    126E  LEU*     1.3    63.3    +      -       -      +
    127E  GLN      3.7     0.2    -      -       -      -
    128E  ASN*     4.3     4.9    -      -       -      +
    129E  CYS*     3.4    32.6    +      -       +      +
    134E  GLU*     3.4    29.2    -      -       +      +
    138E  ILE*     4.1    24.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 126 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    122E  LEU      3.3    11.7    -      -       -      +
    123E  LEU*     3.5    34.8    -      -       +      +
    124E  ILE      3.1     1.2    -      -       -      -
    125E  LEU*     1.3    81.9    -      -       -      +
    127E  GLN*     1.3    63.0    +      -       -      +
    129E  CYS*     4.6     0.2    -      -       -      +
    130E  THR*     3.4    14.7    +      -       -      -
    135E  ARG*     3.5    29.2    +      -       +      +
    138E  ILE*     3.8    37.9    -      -       +      -
     93G  PHE*     5.0     3.1    -      -       +      +
     94G  GLY*     4.5    11.9    -      -       -      -
     95G  SER      5.2     0.2    -      -       -      +
    139G  PRO*     3.7    34.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLN 127 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    124E  ILE      3.9     2.6    +      -       -      -
    126E  LEU*     1.3    78.7    -      -       +      +
    128E  ASN*     1.3    63.9    +      -       -      +
    130E  THR*     2.4    25.9    +      -       -      +
    135E  ARG*     4.9     3.1    -      -       -      +
     93G  PHE*     3.2    37.8    -      -       +      -
     61I  LEU*     5.2    14.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 128 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    124E  ILE*     3.0    40.4    +      -       -      +
    125E  LEU*     4.7     3.8    -      -       -      +
    126E  LEU      3.4     0.6    -      -       -      -
    127E  GLN*     1.3    82.0    -      -       -      +
    129E  CYS*     1.3    64.3    +      -       -      +
    130E  THR*     4.3     0.3    +      -       -      -
     93G  PHE*     5.5     0.8    -      -       -      -
     61I  LEU*     5.0     9.5    -      -       -      +
     63I  ILE*     4.3    19.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with CYS 129 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    102B  ILE*     5.3     8.3    -      -       -      -
    125E  LEU*     3.4    40.6    +      -       -      +
    126E  LEU      4.6     0.2    -      -       -      +
    127E  GLN      3.4     0.2    -      -       -      -
    128E  ASN*     1.3    84.9    -      -       -      +
    130E  THR*     1.3    71.1    +      -       -      +
    131E  ASP*     4.6     4.5    -      -       +      +
    134E  GLU*     3.7    26.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 130 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    126E  LEU      3.4    12.4    +      -       -      -
    127E  GLN*     2.4    33.3    +      -       -      +
    128E  ASN      4.2     0.4    -      -       -      -
    129E  CYS*     1.3    80.1    -      -       -      +
    131E  ASP*     1.3    59.1    +      -       -      +
    132E  GLU*     6.2     0.2    -      -       -      -
    135E  ARG*     4.4    13.0    -      -       -      +
----------------------------------------------------------
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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