Contacts of the helix formed by residues 101 - 128 (chain A) in PDB entry 2QKW


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 LEU 101 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    100A  MET*     1.3    74.6    -      -       -      +
    102A  PRO*     1.3    72.6    -      -       +      +
    103A  HIS*     3.2    26.5    -      -       +      +
    104A  GLU*     2.8    33.1    +      -       -      +
    105A  ASN*     2.8    19.4    +      -       -      -
     49B  HIS*     3.6    42.8    -      -       +      +
     50B  GLY*     3.9    18.6    -      -       -      -
     51B  VAL*     3.9    11.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with PRO 102 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31A  VAL*     4.1    16.6    -      -       +      +
     36A  LEU*     3.8    11.6    -      -       +      +
     86A  GLN*     3.8     9.6    -      -       -      +
     90A  MET*     3.7    39.3    -      -       +      -
    101A  LEU*     1.3    97.1    -      -       +      +
    103A  HIS*     1.3    60.8    +      -       -      +
    105A  ASN*     3.2    18.8    +      -       -      +
    106A  VAL*     3.3    18.2    +      -       -      +
     49B  HIS*     5.1     5.4    -      -       -      +
     51B  VAL*     4.0    16.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with HIS 103 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     29A  ASP*     3.4    40.1    +      -       -      +
     31A  VAL*     3.6    14.1    -      -       +      +
    101A  LEU*     3.5    35.6    -      -       +      +
    102A  PRO*     1.3    78.8    -      -       -      +
    104A  GLU*     1.3    71.6    +      -       +      +
    105A  ASN      3.3     0.2    -      -       -      -
    106A  VAL*     3.2    14.2    -      -       +      +
    107A  ASP*     3.1    41.8    +      -       -      +
     49B  HIS*     4.7     9.8    +      +       -      -
----------------------------------------------------------
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Residues in contact with GLU 104 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    100A  MET*     3.4    21.6    -      -       +      +
    101A  LEU*     2.8    47.2    +      -       -      +
    103A  HIS*     1.3    99.6    -      -       +      +
    105A  ASN*     1.3    56.5    +      -       -      +
    107A  ASP*     3.9     5.0    -      -       -      +
    108A  ASP*     3.1    35.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 105 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     36A  LEU*     4.4    10.1    -      -       +      -
     79A  THR*     4.9     1.3    -      -       +      +
     82A  MET*     3.4    31.9    -      -       -      +
     83A  ALA*     3.6     6.7    +      -       +      +
     86A  GLN*     3.1    26.3    -      -       -      +
    100A  MET*     3.4    18.7    -      -       -      +
    101A  LEU      2.8    27.1    +      -       -      -
    102A  PRO*     3.2     6.3    +      -       -      +
    104A  GLU*     1.3    75.6    -      -       -      +
    106A  VAL*     1.3    60.0    +      -       -      +
    108A  ASP*     3.2     8.4    +      -       -      +
    109A  MET*     2.8    41.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 106 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31A  VAL*     3.8    27.8    -      -       +      -
     36A  LEU*     4.2    20.6    -      -       +      -
     39A  VAL*     4.4    16.6    -      -       +      -
    102A  PRO      3.3    11.2    +      -       -      +
    103A  HIS*     3.2    21.8    -      -       +      +
    105A  ASN*     1.3    75.0    -      -       -      +
    107A  ASP*     1.3    69.2    +      -       -      +
    109A  MET*     3.9    11.9    -      -       +      -
    110A  ARG*     2.8    50.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with ASP 107 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    103A  HIS*     3.1    30.2    +      -       -      +
    104A  GLU*     4.0     7.0    -      -       -      +
    106A  VAL*     1.3    89.4    -      -       -      +
    108A  ASP*     1.3    58.9    +      -       -      +
    110A  ARG*     4.7     8.2    +      -       -      +
    111A  SER*     3.3    23.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with ASP 108 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75A  HIS*     5.0     7.9    -      -       +      -
     79A  THR*     4.2    16.7    +      -       +      +
    100A  MET*     5.6     3.6    -      -       -      +
    104A  GLU*     3.1    25.3    +      -       -      +
    105A  ASN*     3.5     8.0    -      -       -      +
    106A  VAL      3.1     0.6    -      -       -      -
    107A  ASP*     1.3    80.2    -      -       -      +
    109A  MET*     1.3    58.5    +      -       -      +
    111A  SER*     3.3     6.7    -      -       -      -
    112A  ALA*     3.1    22.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with MET 109 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     36A  LEU*     3.6    32.8    -      -       +      +
     39A  VAL*     3.8    14.4    -      -       +      +
     40A  ARG*     3.6    37.9    -      -       -      +
     43A  LEU*     3.5    25.7    -      -       +      +
     79A  THR*     3.6     8.3    -      -       +      -
     80A  LEU*     5.4     0.2    -      -       -      -
     83A  ALA*     3.8    17.9    -      -       +      -
    105A  ASN      2.8    29.8    +      -       -      +
    106A  VAL*     3.8     5.4    -      -       -      +
    108A  ASP*     1.3    75.4    -      -       -      +
    110A  ARG*     1.3    64.7    +      -       -      +
    111A  SER      3.1     1.6    -      -       -      -
    112A  ALA*     3.2     7.6    +      -       -      +
    113A  ILE*     3.1    30.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 110 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39A  VAL*     3.8    35.8    -      -       +      +
     42A  GLN*     4.9     9.3    +      -       -      +
    106A  VAL*     2.8    38.0    +      -       -      +
    107A  ASP*     4.7     8.1    +      -       -      +
    109A  MET*     1.3    75.4    -      -       -      +
    111A  SER*     1.3    60.7    +      -       -      +
    113A  ILE*     3.6    22.3    +      -       +      +
    114A  THR*     3.3    13.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with SER 111 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    107A  ASP      3.3    20.9    +      -       -      -
    108A  ASP*     3.3     8.3    -      -       -      -
    109A  MET      3.1     0.2    -      -       -      -
    110A  ARG*     1.3    80.0    -      -       -      +
    112A  ALA*     1.3    61.6    +      -       -      +
    114A  THR*     3.3    19.5    +      -       -      -
    115A  ASP*     3.0    21.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 112 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     43A  LEU*     3.7    21.8    -      -       +      -
     72A  LEU*     4.4     1.3    -      -       +      +
     75A  HIS*     4.9     8.5    -      -       +      +
     76A  THR*     5.1     7.2    -      -       +      +
     79A  THR*     4.8     9.4    -      -       -      +
    108A  ASP      3.1    15.9    +      -       -      +
    109A  MET*     3.2    12.3    +      -       -      +
    111A  SER*     1.3    76.2    -      -       -      +
    113A  ILE*     1.3    61.6    +      -       -      +
    115A  ASP*     3.3    15.9    +      -       -      +
    116A  TRP*     3.2    27.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 113 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39A  VAL*     4.7     5.8    -      -       +      +
     42A  GLN*     4.1    26.9    -      -       +      +
     43A  LEU*     3.9    26.0    -      -       +      +
     46A  SER*     3.8    27.8    -      -       -      +
    109A  MET      3.1    17.5    +      -       -      +
    110A  ARG*     3.8    20.4    -      -       +      +
    111A  SER      3.2     0.4    -      -       -      -
    112A  ALA*     1.3    74.5    -      -       -      +
    114A  THR*     1.3    65.0    +      -       -      +
    116A  TRP*     3.2     6.8    +      -       -      +
    117A  SER*     3.1    24.7    +      -       -      +
    120A  ARG*     4.6     1.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 114 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    110A  ARG      3.3    11.1    +      -       -      -
    111A  SER*     3.3    14.0    +      -       -      -
    113A  ILE*     1.3    76.6    -      -       -      +
    115A  ASP*     1.3    59.4    +      -       -      +
    117A  SER*     3.1    11.6    +      -       -      +
    118A  ASP*     2.9    48.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 115 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     68A  ARG*     4.8     2.3    +      -       -      -
     72A  LEU*     3.6    23.4    -      -       +      +
     75A  HIS*     5.4     5.0    -      -       -      -
    111A  SER*     3.0    24.0    +      -       -      +
    112A  ALA*     3.3    17.8    -      -       -      +
    113A  ILE      3.2     0.4    -      -       -      -
    114A  THR*     1.3    77.4    -      -       -      +
    116A  TRP*     1.3    57.3    +      -       -      +
    118A  ASP*     3.7     8.5    -      -       -      +
    119A  MET*     3.1    30.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with TRP 116 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     43A  LEU*     4.2     9.2    -      -       +      -
     46A  SER*     3.8     7.4    -      -       -      +
     47A  ALA*     3.6    34.6    -      -       +      +
     48A  GLY      3.9     8.5    -      -       -      -
     49A  LEU*     3.8    25.1    -      -       +      -
     69A  TYR*     3.5    37.9    -      +       -      -
     72A  LEU*     3.6    21.2    -      -       +      +
     73A  TYR*     3.9    24.0    -      +       -      -
     76A  THR*     3.1    28.7    +      -       -      +
    112A  ALA      3.2    21.0    +      -       -      -
    113A  ILE*     3.2     9.9    +      -       -      +
    114A  THR      3.2     0.4    -      -       -      -
    115A  ASP*     1.3    74.4    -      -       -      +
    117A  SER*     1.3    56.8    +      -       -      +
    118A  ASP      3.0     4.5    -      -       -      -
    119A  MET*     3.0     9.9    +      -       +      +
    120A  ARG*     2.9    47.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 117 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    113A  ILE*     3.1    16.5    +      -       -      +
    114A  THR*     3.1    19.1    +      -       -      +
    116A  TRP*     1.3    75.2    -      -       -      +
    118A  ASP*     1.3    62.1    +      -       -      +
    120A  ARG*     3.5    29.1    -      -       -      +
    121A  GLU*     3.6    19.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 118 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     68A  ARG*     4.4    10.8    -      -       -      +
    114A  THR*     2.9    34.7    +      -       -      +
    115A  ASP*     3.7     8.8    +      -       -      +
    117A  SER*     1.3    81.6    +      -       -      +
    119A  MET*     1.3    54.1    +      -       -      +
    120A  ARG      3.2     0.9    -      -       -      -
    121A  GLU*     3.0    16.7    +      -       -      +
    122A  ALA*     2.5    39.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with MET 119 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     49A  LEU*     5.9     0.4    -      -       +      -
     66A  ARG*     5.2     4.5    -      -       +      +
     68A  ARG*     3.2    54.2    -      -       +      +
     69A  TYR*     3.6    32.1    -      -       +      +
     72A  LEU*     3.6    19.7    -      -       +      -
    115A  ASP      3.1    17.6    +      -       -      +
    116A  TRP*     3.0    18.5    +      -       +      +
    118A  ASP*     1.3    74.9    -      -       -      +
    120A  ARG*     1.3    55.7    +      -       +      +
    122A  ALA*     3.1     3.6    +      -       -      -
    123A  LEU*     2.7    75.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 120 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     46A  SER*     3.4    31.2    +      -       -      +
     48A  GLY      4.1    10.2    +      -       -      -
     49A  LEU*     3.7    17.9    -      -       +      +
     50A  PRO*     3.5    21.5    -      -       +      -
     53A  GLN*     2.7    45.0    +      -       -      +
    113A  ILE*     4.6     2.2    +      -       -      +
    116A  TRP*     2.9    18.4    +      -       +      +
    117A  SER*     3.5    42.5    -      -       -      +
    119A  MET*     1.3    76.6    -      -       +      +
    121A  GLU*     1.3    60.4    +      -       -      +
    124A  GLN*     3.4     7.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 121 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    117A  SER      3.6    12.4    +      -       -      +
    118A  ASP*     3.0    23.9    +      -       -      +
    120A  ARG*     1.3    76.9    -      -       -      +
    122A  ALA*     1.3    60.4    +      -       -      +
    123A  LEU      3.2     0.2    -      -       -      -
    124A  GLN*     3.4     5.3    +      -       -      +
    125A  HIS*     2.9    34.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 122 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     66A  ARG*     4.8    12.0    +      -       +      +
     68A  ARG*     3.7    28.0    -      -       -      +
    118A  ASP      2.5    20.4    +      -       -      +
    119A  MET*     3.6     3.4    -      -       -      +
    121A  GLU*     1.3    72.7    -      -       -      +
    123A  LEU*     1.3    60.1    +      -       +      +
    125A  HIS*     3.6     5.4    -      -       -      +
    126A  ALA*     2.9    31.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 123 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     49A  LEU*     3.5    32.3    -      -       +      -
     53A  GLN*     3.6    22.2    -      -       +      +
     56A  PHE      5.8     0.2    -      -       -      +
     57A  VAL*     3.9    23.1    -      -       +      -
     62A  PRO*     4.6    19.7    -      -       +      -
     66A  ARG*     4.7     9.4    -      -       +      +
     69A  TYR*     5.4     0.4    -      -       +      -
    119A  MET*     2.7    52.0    +      -       +      +
    120A  ARG      4.6     0.2    -      -       -      +
    122A  ALA*     1.3    70.1    -      -       +      +
    124A  GLN*     1.3    65.1    +      -       -      +
    125A  HIS      3.1     1.1    -      -       -      -
    126A  ALA*     4.5     2.7    -      -       -      +
    127A  MET*     2.8    37.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 124 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     50A  PRO*     5.7     0.3    -      -       -      +
     52A  ASP*     4.7     6.5    +      -       -      +
     53A  GLN*     2.8    26.9    +      -       -      +
    120A  ARG      3.4    17.9    +      -       -      +
    121A  GLU*     3.7     5.2    -      -       +      +
    123A  LEU*     1.3    77.5    -      -       -      +
    125A  HIS*     1.3    62.0    +      -       -      +
    127A  MET*     3.8    12.0    -      -       -      +
    128A  GLY*     3.2    19.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with HIS 125 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     66A  ARG*     5.8     2.2    +      -       -      -
    121A  GLU*     2.9    20.7    +      -       +      +
    122A  ALA*     3.6     7.0    -      -       -      +
    124A  GLN*     1.3    74.6    -      -       -      +
    126A  ALA*     1.3    67.8    +      -       -      +
    128A  GLY*     3.2    21.1    +      -       -      +
    129A  ILE*     4.9     3.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 126 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     62A  PRO*     4.0    22.2    -      -       +      +
     66A  ARG*     3.6    31.0    -      -       +      +
    122A  ALA      2.9    21.9    +      -       -      +
    123A  LEU*     4.2     1.8    -      -       -      +
    125A  HIS*     1.3    78.1    +      -       -      +
    127A  MET*     1.3    57.7    +      -       -      +
    129A  ILE*     3.1    32.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with MET 127 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     52A  ASP*     3.5    20.2    -      -       -      +
     53A  GLN*     3.7    28.3    -      -       +      +
     56A  PHE*     3.5    41.3    -      -       +      +
     57A  VAL*     5.9     0.2    -      -       +      -
     60A  GLN*     6.1     0.9    -      -       +      +
     62A  PRO*     5.5     2.0    -      -       +      +
    123A  LEU*     2.8    30.8    +      -       +      +
    124A  GLN*     3.8    12.6    -      -       -      +
    126A  ALA*     1.3    74.2    -      -       -      +
    128A  GLY*     1.3    60.4    +      -       -      +
    129A  ILE*     2.9    19.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 128 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    124A  GLN      3.2    13.0    +      -       -      -
    125A  HIS      3.2    15.4    +      -       -      +
    127A  MET*     1.3    74.2    -      -       -      +
    129A  ILE*     1.3    59.0    +      -       -      +
----------------------------------------------------------
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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