Contacts of the helix formed by residues 55 - 80 (chain X) in PDB entry 1V7M


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 MET 55 (chain X).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     53X  THR      3.8     2.8    +      -       -      +
     54X  GLN*     1.3    76.6    -      -       -      +
     56X  GLU*     1.3    83.3    +      -       +      +
     57X  GLU*     4.7     4.0    -      -       +      +
     58X  THR*     3.2    16.4    +      -       -      +
     59X  LYS*     2.9    24.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 56 (chain X). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     52X  LYS*     5.0     3.3    +      -       -      +
     54X  GLN      3.6     2.9    +      -       -      +
     55X  MET*     1.3    86.3    -      -       +      +
     57X  GLU*     1.3    61.8    +      -       -      +
     59X  LYS*     2.9    49.9    +      -       -      +
     60X  ALA*     3.3     9.5    +      -       -      +
    142X  LEU*     3.7    20.8    -      -       +      +
    145X  VAL*     3.1    39.1    -      -       +      +
    146X  GLY*     4.6     1.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 57 (chain X). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30M  SER*     2.6    30.2    +      -       -      -
     31M  TYR*     3.2    25.2    -      -       +      +
     55X  MET*     3.4     3.9    -      -       +      +
     56X  GLU*     1.3    78.1    -      -       -      +
     58X  THR*     1.3    57.5    +      -       -      +
     60X  ALA*     3.2     8.1    +      -       -      +
     61X  GLN*     3.1    28.8    +      -       -      +
    107X  LEU*     6.5     0.7    -      -       +      -
    108X  LEU*     4.0    24.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with THR 58 (chain X). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31M  TYR*     2.6    32.8    +      -       -      -
     54X  GLN*     3.3    39.7    -      -       +      +
     55X  MET*     3.2    19.6    +      -       -      +
     57X  GLU*     1.3    73.6    -      -       -      +
     59X  LYS*     1.3    66.1    +      -       -      +
     60X  ALA      3.0     1.1    -      -       -      -
     61X  GLN*     3.5     5.9    +      -       +      +
     62X  ASP*     2.7    36.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 59 (chain X). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     51X  TRP*     3.5    56.7    -      -       +      +
     52X  LYS*     2.7    59.5    +      -       -      +
     54X  GLN*     3.6    12.8    +      -       +      +
     55X  MET      2.9    13.8    +      -       -      +
     56X  GLU*     2.9    45.3    +      -       -      +
     58X  THR*     1.3    77.5    -      -       -      +
     60X  ALA*     1.3    62.5    +      -       -      +
     62X  ASP*     3.4     2.5    +      -       -      +
     63X  ILE*     3.1    16.3    +      -       -      +
    141X  PHE      4.9     7.2    -      -       -      -
    142X  LEU*     3.7     8.7    -      -       +      -
    145X  VAL*     5.7     0.4    -      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 60 (chain X). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     56X  GLU      3.3     3.7    +      -       -      +
     57X  GLU*     3.2    11.3    +      -       -      +
     58X  THR      3.0     0.6    -      -       -      -
     59X  LYS*     1.3    78.1    -      -       -      +
     61X  GLN*     1.3    54.7    +      -       -      +
     63X  ILE*     2.8    12.0    +      -       -      +
     64X  LEU*     2.8    32.6    +      -       -      +
    104X  LEU*     4.4     7.0    -      -       +      +
    107X  LEU*     4.3    15.9    -      -       +      -
    108X  LEU*     4.0    20.3    -      -       +      +
    142X  LEU*     3.8    23.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLN 61 (chain X). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31M  TYR*     3.2    43.6    -      -       +      +
     33M  TYR*     3.5    15.8    +      -       -      -
     49M  SER*     2.8    29.8    +      -       -      +
     57X  GLU*     3.3    13.2    +      -       -      +
     58X  THR*     3.5    10.3    +      -       -      +
     60X  ALA*     1.3    73.0    -      -       -      +
     62X  ASP*     1.3    69.0    -      -       -      +
     64X  LEU*     3.0     4.0    +      -       -      +
     65X  GLY*     3.0    19.2    +      -       -      -
    108X  LEU*     3.8    21.8    -      -       +      +
    110X  THR*     5.1     3.8    -      -       -      +
    112X  LEU*     3.8    22.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASP 62 (chain X). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     51X  TRP*     3.7    20.6    -      -       +      +
     54X  GLN*     3.4    18.6    -      -       -      +
     58X  THR*     2.7    31.5    +      -       -      +
     59X  LYS      3.6     7.6    -      -       -      +
     61X  GLN*     1.3    74.8    -      -       -      +
     63X  ILE*     1.3    65.0    +      -       -      +
     65X  GLY*     3.0     4.0    +      -       -      +
     66X  ALA*     3.0    20.9    +      -       -      +
    115X  GLN*     5.9     6.5    -      -       -      +
    117X  ARG*     5.7     1.7    +      -       -      -
    138X  LYS*     5.4     3.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 63 (chain X). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     51X  TRP*     3.6    14.1    -      -       +      -
     59X  LYS      3.1    12.1    +      -       -      +
     60X  ALA*     2.8     9.8    +      -       -      +
     62X  ASP*     1.3    75.4    -      -       -      +
     64X  LEU*     1.3    58.1    +      -       -      +
     66X  ALA*     3.0     7.9    +      -       -      +
     67X  VAL*     2.8    34.6    +      -       +      +
    104X  LEU*     3.3    24.2    -      -       +      -
    134X  LEU*     5.0     4.9    -      -       +      -
    138X  LYS*     3.2    52.9    -      -       +      +
    139X  VAL*     3.7    22.4    -      -       +      +
    142X  LEU*     4.1    17.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 64 (chain X). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     60X  ALA      2.8    11.7    +      -       -      +
     61X  GLN      3.0     7.8    +      -       -      +
     63X  ILE*     1.3    77.3    -      -       -      +
     65X  GLY*     1.3    52.8    +      -       -      +
     67X  VAL*     4.5     0.9    -      -       +      -
     68X  THR*     2.6    54.1    +      -       +      +
    101X  LEU*     4.1     6.5    -      -       +      -
    104X  LEU*     3.7    23.3    -      -       +      -
    105X  GLN*     3.6    27.8    -      -       +      +
    108X  LEU*     3.7    26.0    -      -       +      -
    110X  THR      3.7    21.5    -      -       -      +
    112X  LEU*     3.7    26.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 65 (chain X). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     61X  GLN      3.0    12.7    +      -       -      -
     62X  ASP*     3.0     3.8    +      -       -      -
     64X  LEU*     1.3    77.4    -      -       -      +
     66X  ALA*     1.3    61.8    +      -       -      +
     68X  THR*     2.8    19.2    +      -       -      -
     69X  LEU*     2.9    15.2    +      -       -      +
    112X  LEU*     4.9     3.3    -      -       -      +
    113X  PRO      3.7    15.0    -      -       -      -
    115X  GLN*     3.8    19.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 66 (chain X). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     42X  PRO*     3.3    24.4    -      -       +      +
     62X  ASP      3.0    10.7    +      -       -      +
     63X  ILE*     3.0    12.1    +      -       -      +
     65X  GLY*     1.3    75.3    -      -       -      +
     67X  VAL*     1.3    57.8    +      -       -      +
     69X  LEU*     3.4     1.4    +      -       -      -
     70X  LEU*     2.9    25.1    +      -       -      +
    115X  GLN      4.2    10.2    +      -       -      +
    116X  GLY*     6.2     0.9    -      -       -      -
    134X  LEU*     3.9    22.7    -      -       +      -
    138X  LYS*     5.7     6.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 67 (chain X). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     63X  ILE*     2.8    25.6    +      -       +      +
     64X  LEU*     3.8     3.6    -      -       -      +
     66X  ALA*     1.3    74.2    -      -       -      +
     68X  THR*     1.3    60.8    +      -       -      +
     70X  LEU*     3.6     7.6    -      -       +      +
     71X  LEU*     2.8    28.1    +      -       -      +
     97X  VAL*     3.8    22.0    -      -       +      -
    100X  LEU*     3.2    34.3    -      -       +      -
    101X  LEU*     4.1    25.4    -      -       +      +
    104X  LEU*     3.7    10.3    -      -       +      -
    134X  LEU*     4.2    11.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 68 (chain X). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    101I  TRP*     4.0    17.4    -      -       +      -
     64X  LEU*     2.6    35.1    +      -       +      +
     65X  GLY*     2.8    15.8    +      -       -      -
     67X  VAL*     1.3    77.1    -      -       -      +
     69X  LEU*     1.3    57.3    +      -       -      -
     71X  LEU*     3.4     7.4    +      -       -      +
     72X  GLU*     3.3    21.5    +      -       -      +
    101X  LEU*     3.0    31.9    -      -       +      -
    105X  GLN*     4.3     2.0    -      -       -      +
    112X  LEU      3.9    16.1    +      -       -      +
    113X  PRO      3.7     8.5    +      -       -      -
    114X  PRO*     3.9     8.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 69 (chain X). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     40X  LEU*     4.1    19.2    -      -       +      +
     41X  LEU*     4.1     1.3    -      -       -      -
     42X  PRO*     3.8    30.7    -      -       +      -
     65X  GLY      2.9    16.4    +      -       -      +
     66X  ALA*     3.8     1.3    -      -       -      +
     68X  THR*     1.3    72.9    +      -       -      +
     70X  LEU*     1.3    66.0    +      -       -      +
     72X  GLU*     3.2    21.2    +      -       -      +
     73X  GLY*     2.9    19.4    +      -       -      -
    114X  PRO*     3.8    21.5    -      -       +      +
    115X  GLN      4.0    18.8    -      -       -      +
    117X  ARG      4.7     1.1    -      -       -      +
    118X  THR*     3.5    32.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 70 (chain X). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     41X  LEU*     4.5    10.5    -      -       +      +
     42X  PRO*     3.8    16.3    -      -       +      +
     66X  ALA      2.9    17.9    +      -       -      +
     67X  VAL*     3.6     7.4    -      -       +      +
     69X  LEU*     1.3    72.4    -      -       -      +
     71X  LEU*     1.3    53.1    +      -       -      +
     72X  GLU      2.6    16.5    +      -       -      -
     73X  GLY*     2.6    14.7    +      -       -      -
     74X  VAL*     3.0    28.5    +      -       +      +
     93X  LEU*     5.2     0.7    -      -       +      -
     97X  VAL*     3.5    38.1    -      -       +      -
    127X  ILE*     4.1    19.7    -      -       +      +
    130X  SER*     4.5     9.6    -      -       -      +
    131X  PHE*     3.7    31.6    -      -       +      +
    134X  LEU*     5.2     5.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 71 (chain X). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     28I  THR*     5.7     1.8    -      -       +      -
     31I  ASP*     3.2    28.7    -      -       -      +
    101I  TRP*     4.9    10.8    -      -       +      -
     67X  VAL      2.8    20.8    +      -       -      +
     68X  THR*     3.7     7.9    -      -       -      +
     69X  LEU      3.4     0.4    -      -       -      -
     70X  LEU*     1.3    73.8    -      -       -      +
     72X  GLU*     1.3    58.7    +      -       +      +
     74X  VAL*     3.7     8.9    -      -       -      +
     75X  MET*     2.9    35.9    +      -       +      +
     94X  SER*     4.0     3.8    -      -       -      +
     97X  VAL*     3.8    25.6    -      -       +      -
     98X  ARG*     3.2    43.5    -      -       +      +
    101X  LEU*     4.7    14.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 72 (chain X). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    105I  TYR*     5.4     3.3    +      -       -      -
     40X  LEU*     6.1     0.3    -      -       -      +
     68X  THR      3.3    11.9    +      -       -      +
     69X  LEU*     3.2    23.8    +      -       -      +
     70X  LEU      2.6     5.9    +      -       -      -
     71X  LEU*     1.3    75.8    -      -       +      +
     73X  GLY*     1.3    62.8    +      -       -      +
     75X  MET*     4.1     5.4    -      -       -      +
     76X  ALA*     2.9    27.0    +      -       +      +
    114X  PRO*     3.9    24.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 73 (chain X). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39X  VAL*     3.3    24.1    -      -       -      +
     40X  LEU      3.4    23.8    +      -       -      -
     41X  LEU*     4.1     4.0    -      -       -      -
     69X  LEU      2.9     8.7    +      -       -      -
     70X  LEU      2.6    12.0    +      -       -      -
     72X  GLU*     1.3    71.4    -      -       -      +
     74X  VAL*     1.3    63.4    +      -       -      +
     76X  ALA*     3.2    11.9    +      -       -      +
     77X  ALA*     3.2     8.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 74 (chain X). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     41X  LEU*     4.6     1.8    -      -       -      +
     70X  LEU*     3.0    39.0    +      -       +      +
     71X  LEU*     3.7     9.2    -      -       -      +
     73X  GLY*     1.3    72.4    -      -       -      +
     75X  MET*     1.3    60.3    +      -       +      +
     77X  ALA*     2.9    23.9    +      -       -      +
     78X  ARG*     3.2    13.0    +      -       -      +
     90X  LEU*     3.6    29.4    -      -       +      +
     93X  LEU*     4.1    21.3    -      -       +      -
     94X  SER*     4.0    13.9    -      -       -      -
     97X  VAL*     4.9     5.2    -      -       +      -
    127X  ILE*     4.5    14.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with MET 75 (chain X). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     28I  THR*     3.8    31.0    -      -       +      -
     71X  LEU*     2.9    25.0    +      -       +      +
     72X  GLU*     4.1     6.1    -      -       -      +
     74X  VAL*     1.3    76.4    -      -       +      +
     76X  ALA*     1.3    62.8    +      -       -      +
     78X  ARG*     3.5    25.2    +      -       +      +
     79X  GLY*     3.1    19.9    +      -       -      -
     94X  SER*     4.6     6.1    -      -       -      -
     98X  ARG*     3.6    28.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 76 (chain X). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39X  VAL*     3.8    13.9    -      -       +      -
     72X  GLU*     2.9    21.8    +      -       +      +
     73X  GLY*     3.2     8.7    +      -       -      +
     75X  MET*     1.3    76.1    -      -       -      +
     77X  ALA*     1.3    60.3    +      -       -      +
     79X  GLY*     3.7     5.5    +      -       -      -
     80X  GLN*     3.2    26.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 77 (chain X). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     35X  LEU*     4.5    18.5    -      -       +      +
     39X  VAL*     4.0    10.0    -      -       +      +
     73X  GLY      3.2     8.6    +      -       -      +
     74X  VAL*     2.9    12.6    +      -       -      +
     76X  ALA*     1.3    73.0    -      -       -      +
     78X  ARG*     1.3    67.9    +      -       -      +
     79X  GLY      2.9     1.3    -      -       -      -
     80X  GLN*     2.8    28.6    +      -       -      +
     81X  LEU*     3.6    12.0    -      -       +      +
     90X  LEU*     3.7    19.1    -      -       +      -
    127X  ILE*     5.2     5.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 78 (chain X). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     74X  VAL*     3.2     7.0    +      -       -      +
     75X  MET*     3.7    33.8    -      -       +      +
     77X  ALA*     1.3    78.3    -      -       -      +
     79X  GLY*     1.3    60.2    +      -       -      +
     81X  LEU*     3.1    28.3    +      -       -      +
     87X  SER*     2.6    56.6    +      -       -      +
     88X  SER*     4.7     2.2    +      -       -      +
     90X  LEU*     4.0    20.7    -      -       +      +
     91X  GLY*     3.3    28.5    -      -       -      +
     94X  SER*     4.7     2.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLY 79 (chain X). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75X  MET      3.1    14.1    +      -       -      -
     76X  ALA*     4.1     4.5    -      -       -      -
     77X  ALA      2.9     2.2    +      -       -      -
     78X  ARG*     1.3    77.1    -      -       -      +
     80X  GLN*     1.3    58.2    +      -       -      +
     81X  LEU      3.1     6.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 80 (chain X). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     35X  LEU*     3.5     7.6    -      -       +      +
     36X  PRO*     3.4    29.7    -      -       +      +
     37X  THR*     2.7    61.1    +      -       -      +
     38X  PRO      4.8     0.4    +      -       -      -
     39X  VAL*     3.6    18.2    -      -       -      +
     76X  ALA*     3.2    21.2    +      -       -      +
     77X  ALA*     2.8    10.0    +      -       -      +
     79X  GLY*     1.3    77.1    -      -       -      +
     81X  LEU*     1.3    63.6    +      -       +      +
----------------------------------------------------------
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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