Contacts of the helix formed by residues 117 - 142 (chain A) in PDB entry 1SGM


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 SER 117 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     52A  GLU*     2.6    29.4    +      -       -      -
    113A  THR*     3.6     3.7    -      -       -      +
    116A  ILE*     1.3    84.6    -      -       -      +
    118A  GLU*     1.3    61.8    +      -       -      +
    119A  PRO*     3.4     5.0    -      -       -      +
    120A  LEU*     2.8    34.6    +      -       -      +
    121A  ARG*     3.2    15.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 118 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    114A  ALA      4.1     3.3    -      -       -      +
    115A  LEU      5.9     0.3    -      -       -      -
    116A  ILE      3.5     1.4    +      -       -      +
    117A  SER*     1.3    70.7    -      -       -      +
    119A  PRO*     1.3    63.6    -      -       +      +
    121A  ARG*     2.8    45.4    +      -       -      +
    122A  THR*     2.5    41.8    +      -       -      +
    171B  LYS*     3.0    19.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with PRO 119 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     52A  GLU*     4.4    13.7    -      -       -      +
     56A  ILE*     3.9    20.2    -      -       +      -
    117A  SER*     3.2    12.6    -      -       -      +
    118A  GLU*     1.3    96.0    -      -       +      +
    120A  LEU*     1.3    59.0    +      -       -      +
    122A  THR*     3.3     5.5    +      -       -      +
    123A  VAL*     3.0    33.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 120 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24A  TYR*     4.2    17.7    -      -       +      +
     52A  GLU*     3.3    24.0    -      -       +      +
     55A  ALA*     3.8    24.0    -      -       +      -
     56A  ILE*     3.6    26.9    -      -       +      +
     59A  VAL*     5.1     2.2    -      -       +      -
    109A  LEU*     4.3    10.8    -      -       +      -
    113A  THR*     3.5    28.7    -      -       +      +
    117A  SER*     2.8    33.0    +      -       -      +
    119A  PRO*     1.3    73.9    -      -       -      +
    121A  ARG*     1.3    67.3    +      -       -      +
    122A  THR      3.3     0.2    +      -       -      -
    123A  VAL*     3.4     4.6    +      -       +      +
    124A  CYS*     3.1    28.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 121 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    110A  ALA      5.6     1.6    -      -       -      +
    113A  THR*     4.4     4.1    +      -       -      -
    114A  ALA*     3.6    32.3    -      -       -      +
    117A  SER      3.2    14.6    +      -       -      +
    118A  GLU*     2.8    40.1    +      -       -      +
    120A  LEU*     1.3    79.0    -      -       -      +
    122A  THR*     1.3    60.0    +      -       -      +
    124A  CYS*     3.3     6.7    +      -       -      +
    125A  MET*     2.9    56.1    +      -       -      +
    168B  LEU      4.2     2.0    -      -       -      -
    169B  THR*     2.9    42.2    +      -       +      +
    170B  ASN      3.8     5.9    +      -       -      -
    171B  LYS*     3.6    31.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 122 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    118A  GLU*     2.5    33.4    +      -       -      +
    119A  PRO*     3.5     7.5    -      -       -      +
    121A  ARG*     1.3    82.1    +      -       -      +
    123A  VAL*     1.3    65.4    +      -       +      +
    125A  MET*     3.3    21.1    +      -       +      +
    126A  LYS*     3.0    38.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 123 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     56A  ILE*     3.4    42.2    -      -       +      +
     59A  VAL*     4.3    12.8    -      -       +      -
     60A  THR*     3.5    24.7    -      -       -      +
    119A  PRO      3.0    17.8    +      -       -      +
    120A  LEU*     3.9     4.3    -      -       +      +
    122A  THR*     1.3    78.5    -      -       +      +
    124A  CYS*     1.3    57.9    +      -       -      +
    126A  LYS*     3.4    16.5    +      -       +      +
    127A  VAL*     2.9    31.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with CYS 124 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     59A  VAL*     4.0    10.8    -      -       -      -
    106A  VAL*     3.7    22.6    -      -       +      +
    109A  LEU*     3.8    17.9    -      -       -      -
    110A  ALA*     3.6    40.8    -      -       +      -
    120A  LEU      3.1    21.6    +      -       -      +
    121A  ARG*     3.6     5.4    -      -       -      +
    123A  VAL*     1.3    73.6    -      -       -      +
    125A  MET*     1.3    64.9    +      -       -      +
    127A  VAL*     3.3     1.6    +      -       -      +
    128A  PHE*     3.0    28.1    +      -       +      -
    169B  THR*     4.0     5.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with MET 125 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    121A  ARG*     2.9    45.0    +      -       -      +
    122A  THR*     3.3    23.5    +      -       +      +
    124A  CYS*     1.3    75.2    -      -       -      +
    126A  LYS*     1.3    59.3    +      -       +      +
    128A  PHE*     3.5     4.1    +      -       -      +
    129A  LYS*     3.1    44.3    +      -       +      +
    169B  THR*     3.8    11.9    -      -       +      +
    170B  ASN*     3.2    34.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 126 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     60A  THR*     5.6     1.6    +      -       -      -
    122A  THR*     3.0    34.6    +      -       +      +
    123A  VAL*     3.7    17.3    +      -       +      +
    124A  CYS      3.2     0.2    -      -       -      -
    125A  MET*     1.3    79.1    -      -       +      +
    127A  VAL*     1.3    66.5    +      -       -      +
    129A  LYS*     3.2    10.0    +      -       +      +
    130A  SER*     3.0    21.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 127 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     59A  VAL*     3.8    24.2    -      -       +      +
     60A  THR*     4.3    10.1    -      -       +      +
     63A  GLY*     3.5    18.4    -      -       -      -
    106A  VAL*     3.9    10.3    -      -       +      -
    123A  VAL*     2.9    25.2    +      -       +      +
    124A  CYS*     3.3     6.7    +      -       -      +
    126A  LYS*     1.3    79.4    -      -       +      +
    128A  PHE*     1.3    63.3    +      -       -      +
    130A  SER*     2.4    26.7    +      -       -      +
    131A  TRP*     3.1    36.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 128 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    106A  VAL*     4.1    10.5    -      -       +      -
    107A  GLY*     3.8    16.8    -      -       -      -
    110A  ALA*     4.4     5.4    -      -       +      -
    124A  CYS      3.0    21.0    +      -       -      +
    125A  MET*     3.7     5.6    -      -       -      +
    127A  VAL*     1.3    75.8    -      -       -      +
    129A  LYS*     1.3    57.7    +      -       +      +
    131A  TRP*     3.0    31.6    +      +       -      +
    132A  GLU*     2.9    39.2    +      -       -      +
    157A  ASN*     3.5    20.8    -      -       -      +
    161A  GLU*     3.4    35.9    -      -       +      -
    165B  MET*     4.9     4.3    -      -       +      -
    166B  LEU*     5.0    13.2    -      -       +      -
    169B  THR*     3.7    35.0    -      -       +      -
    170B  ASN*     5.2     3.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 129 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    125A  MET*     3.1    42.5    +      -       +      +
    126A  LYS*     3.4    11.0    -      -       +      +
    127A  VAL      3.2     0.2    -      -       -      -
    128A  PHE*     1.3    75.9    -      -       -      +
    130A  SER*     1.3    57.5    +      -       -      +
    132A  GLU*     3.3    22.7    +      -       -      +
    133A  ALA*     2.8    30.2    +      -       -      +
    154A  THR*     6.2     0.6    -      -       -      -
    170B  ASN*     4.4    17.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with SER 130 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     63A  GLY      4.9     1.7    +      -       -      -
     67A  GLU*     4.2    23.0    +      -       -      +
    126A  LYS      3.0    11.8    +      -       -      -
    127A  VAL*     2.4    29.4    +      -       -      +
    129A  LYS*     1.3    78.1    -      -       -      +
    131A  TRP*     1.3    68.9    +      -       -      +
    133A  ALA*     3.4     9.5    +      -       -      +
    134A  VAL*     3.3    24.7    +      -       -      +
    137A  ARG*     4.9     0.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with TRP 131 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     63A  GLY*     3.0    24.6    +      -       -      -
     66A  VAL*     3.4    39.0    -      -       +      +
     67A  GLU*     4.0    13.2    -      -       -      -
     70A  ILE*     3.7    18.6    -      -       +      +
    105A  PRO*     4.3    11.4    -      -       +      -
    106A  VAL*     3.4    37.5    -      -       +      -
    127A  VAL*     3.3    21.5    -      -       +      +
    128A  PHE*     3.0    30.1    +      +       -      +
    130A  SER*     1.3    83.4    +      -       -      +
    132A  GLU*     1.3    67.7    +      -       -      +
    134A  VAL*     3.0    21.6    +      -       -      +
    135A  PHE*     3.4    14.4    +      -       +      -
    157A  ASN*     3.6    22.7    -      -       -      +
    161A  GLU*     4.1    12.3    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 132 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    128A  PHE*     2.9    26.3    +      -       -      +
    129A  LYS*     3.6    24.6    +      -       +      +
    131A  TRP*     1.3    75.8    -      -       -      +
    133A  ALA*     1.3    57.8    +      -       -      +
    135A  PHE*     3.2     9.7    +      -       -      +
    136A  ALA*     2.9    27.9    +      -       -      +
    150A  ASN*     4.7     4.0    -      -       -      +
    153A  GLY*     3.5    28.4    -      -       -      +
    154A  THR*     3.3    29.8    +      -       -      +
    157A  ASN*     3.0    26.1    -      -       +      +
    166B  LEU*     3.8    15.2    -      -       -      +
    170B  ASN*     5.3     0.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 133 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    129A  LYS      2.8    17.6    +      -       -      +
    130A  SER*     3.5    10.8    -      -       -      +
    131A  TRP      3.1     0.4    -      -       -      -
    132A  GLU*     1.3    77.2    -      -       -      +
    134A  VAL*     1.3    56.6    +      -       -      +
    136A  ALA*     3.6     8.5    -      -       -      +
    137A  ARG*     2.8    47.8    +      -       -      +
    150A  ASN*     5.1     2.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 134 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     67A  GLU*     3.8    28.0    -      -       +      +
     70A  ILE*     3.4    24.5    -      -       +      -
     71A  GLN*     3.3    36.2    -      -       +      +
     74A  MET*     4.0     5.5    -      -       +      +
    130A  SER      3.3    16.6    -      -       -      +
    131A  TRP*     3.0    10.0    +      -       -      +
    133A  ALA*     1.3    78.0    -      -       -      +
    135A  PHE*     1.3    62.9    +      -       -      +
    137A  ARG*     3.4    21.8    +      -       -      +
    138A  LYS*     3.3    21.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 135 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     70A  ILE*     3.6    30.7    -      -       +      -
     74A  MET*     4.1    22.8    -      -       +      +
     84A  ILE*     4.3    16.6    -      -       +      +
     87A  PHE*     4.0    26.7    -      +       -      -
    131A  TRP*     3.4    23.3    +      -       +      -
    132A  GLU*     3.2    12.2    +      -       -      +
    134A  VAL*     1.3    75.5    -      -       -      +
    136A  ALA*     1.3    64.5    +      -       -      +
    138A  LYS*     3.2     5.9    +      -       -      +
    139A  LEU*     3.1    27.5    +      -       +      +
    153A  GLY*     4.1    16.8    -      -       -      +
    156A  ILE*     3.8    37.5    -      -       +      -
    157A  ASN*     4.5    13.0    -      -       +      -
    160A  ILE*     4.0     6.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 136 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    132A  GLU      2.9    15.9    +      -       -      +
    133A  ALA*     3.6     7.0    -      -       -      +
    135A  PHE*     1.3    77.7    -      -       -      +
    137A  ARG*     1.3    57.3    +      -       -      +
    139A  LEU*     3.1     3.6    +      -       -      +
    140A  MET*     2.8    37.7    +      -       +      +
    149A  ALA*     3.8    24.8    +      -       +      +
    150A  ASN*     3.0    33.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 137 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     67A  GLU*     4.6     9.5    +      -       -      -
     71A  GLN*     2.5    34.1    +      -       -      +
    130A  SER      4.9     0.4    +      -       -      -
    133A  ALA*     2.8    31.3    +      -       -      +
    134A  VAL*     3.7    29.9    -      -       -      +
    135A  PHE      3.3     0.2    -      -       -      -
    136A  ALA*     1.3    72.2    -      -       +      +
    138A  LYS*     1.3    57.5    -      -       -      +
    140A  MET*     3.3    12.1    +      -       +      +
    141A  GLU*     2.9    43.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 138 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     74A  MET*     2.7    61.0    +      -       +      +
     75A  ASP*     4.7     4.6    +      -       -      +
     77A  SER      2.8    19.9    +      -       -      -
     78A  SER*     3.9     9.7    +      -       -      +
     80A  PRO*     4.3    18.8    -      -       +      -
     83A  ALA*     4.4     1.6    -      -       -      -
     84A  ILE*     5.9     1.6    -      -       +      -
    134A  VAL      3.3     5.9    +      -       -      +
    135A  PHE      3.2    10.0    +      -       -      +
    137A  ARG*     1.3    78.2    -      -       -      +
    139A  LEU*     1.3    62.3    +      -       +      +
    141A  GLU*     3.4    17.8    +      -       -      +
    142A  ASN*     2.9    47.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 139 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     80A  PRO*     3.9    17.7    -      -       +      -
     84A  ILE*     4.5     8.7    -      -       +      -
    135A  PHE      3.1    19.5    +      -       -      +
    136A  ALA      3.5     5.8    -      -       -      +
    138A  LYS*     1.3    77.4    -      -       +      +
    140A  MET*     1.3    61.9    +      -       -      +
    142A  ASN*     2.9    13.7    +      -       -      -
    143A  GLY      3.3     0.7    +      -       -      -
    144A  PHE*     3.0    40.3    +      -       +      +
    149A  ALA*     3.8    17.3    -      -       +      +
    152A  LEU*     3.6    39.5    -      -       +      -
    153A  GLY      4.9     0.7    -      -       -      +
    156A  ILE*     4.9     8.1    -      -       +      -
    187A  VAL*     3.4    29.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with MET 140 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    136A  ALA*     2.8    27.7    +      -       +      +
    137A  ARG*     3.6    12.6    -      -       +      +
    139A  LEU*     1.3    73.6    -      -       -      +
    141A  GLU*     1.3    61.8    +      -       +      +
    142A  ASN      3.1     0.9    +      -       -      -
    143A  GLY*     3.1    11.8    +      -       -      -
    144A  PHE      3.5    16.9    -      -       -      +
    146A  GLU*     3.9    39.3    -      -       +      +
    149A  ALA*     3.7     9.9    -      -       +      -
    150A  ASN*     3.8    26.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 141 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    137A  ARG*     2.9    35.4    +      -       +      +
    138A  LYS*     3.7    24.2    +      -       -      +
    140A  MET*     1.3    76.5    -      -       +      +
    142A  ASN*     1.3    62.9    +      -       -      +
    143A  GLY      3.8     0.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with ASN 142 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     78A  SER      3.4    19.7    +      -       -      +
     80A  PRO*     3.1    33.8    -      -       +      +
    138A  LYS*     2.9    35.4    +      -       -      +
    139A  LEU*     2.9     9.3    +      -       -      +
    141A  GLU*     1.3    83.5    -      -       -      +
    143A  GLY*     1.3    56.3    +      -       -      +
    144A  PHE*     3.6    10.5    +      -       +      -
----------------------------------------------------------
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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