Contacts of the helix formed by residues 125 - 156 (chain A) in PDB entry 1T7S


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 GLU 125 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    124A  LEU*     1.3    99.2    -      -       +      +
    126A  LYS*     1.3    65.8    +      -       -      +
    127A  PRO*     3.3    10.8    -      -       +      -
    128A  LYS*     3.0    33.1    +      -       +      +
    129A  GLN*     3.1     9.1    +      -       -      +
----------------------------------------------------------
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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
----------------------------------------------------------
    124A  LEU      3.9     0.2    -      -       -      -
    125A  GLU*     1.3    71.5    -      -       -      +
    127A  PRO*     1.3    70.0    -      -       +      +
    129A  GLN*     3.1    26.0    +      -       +      +
    130A  VAL*     3.1    28.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with PRO 127 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    125A  GLU*     3.3    11.9    -      -       +      -
    126A  LYS*     1.3    95.3    -      -       +      +
    128A  LYS*     1.3    61.3    +      -       +      +
    130A  VAL*     3.5     9.2    +      -       +      +
    131A  GLU*     3.2    32.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 128 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    124A  LEU      5.0     1.3    -      -       -      +
    125A  GLU*     3.0    27.3    +      -       +      +
    127A  PRO*     1.3    79.1    -      -       +      +
    129A  GLN*     1.3    60.9    +      -       +      +
    131A  GLU*     3.5    12.9    +      -       +      +
    132A  MSE      3.0    37.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 129 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    119A  LEU*     3.2    41.7    +      -       +      +
    122A  GLY*     3.0    41.3    -      -       -      +
    123A  PHE      3.5     5.4    +      -       -      +
    124A  LEU      3.5    12.6    +      -       -      +
    125A  GLU      3.1    13.4    +      -       -      +
    126A  LYS*     3.1    18.3    +      -       +      +
    128A  LYS*     1.3    76.2    -      -       +      +
    130A  VAL*     1.3    60.3    +      -       +      +
    132A  MSE      3.0     6.6    +      -       -      +
    133A  GLY*     2.8    26.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 130 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    126A  LYS*     3.1    28.4    +      -       +      +
    127A  PRO*     3.7     9.4    -      -       +      +
    129A  GLN*     1.3    76.8    -      -       +      +
    131A  GLU*     1.3    62.9    +      -       +      +
    133A  GLY*     3.4     2.5    +      -       -      +
    134A  LYS*     3.1    40.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 131 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    127A  PRO*     3.2    18.3    +      -       -      +
    128A  LYS*     3.7    14.2    -      -       -      +
    130A  VAL*     1.3    74.9    -      -       +      +
    132A  MSE      1.3    64.5    +      -       +      +
    134A  LYS*     3.1    22.4    -      -       -      +
    135A  LYS*     3.1    23.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with MSE 132 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    115A  ASP*     4.8    13.0    -      -       +      +
    119A  LEU*     4.5    11.4    -      -       +      -
    128A  LYS*     3.0    28.8    +      -       +      +
    129A  GLN*     3.0    13.5    +      -       -      +
    131A  GLU*     1.3    73.5    -      -       -      +
    133A  GLY*     1.3    67.0    +      -       -      +
    134A  LYS      3.0     1.4    +      -       -      -
    135A  LYS*     3.0    20.6    +      -       +      +
    136A  LEU*     2.9    55.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 133 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    119A  LEU*     3.8    20.5    -      -       -      +
    129A  GLN      2.8    17.4    +      -       -      -
    130A  VAL*     3.9     2.2    -      -       -      -
    132A  MSE      1.3    72.7    -      -       -      +
    134A  LYS*     1.3    53.6    +      -       -      +
    136A  LEU*     3.5     4.6    -      -       -      +
    137A  GLU*     2.6    41.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 134 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    130A  VAL*     3.1    33.5    +      -       +      +
    131A  GLU*     3.1    15.7    -      -       -      +
    132A  MSE      3.0     0.2    -      -       -      -
    133A  GLY*     1.3    76.6    -      -       -      +
    135A  LYS*     1.3    66.1    +      -       +      +
    137A  GLU*     3.1    18.6    +      -       -      +
    138A  LYS*     2.9    23.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 135 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    131A  GLU*     3.3    22.2    -      -       -      +
    132A  MSE      3.0    21.4    +      -       +      +
    134A  LYS*     1.3    78.4    -      -       +      +
    136A  LEU*     1.3    59.5    +      -       +      +
    138A  LYS*     3.1    14.0    +      -       -      +
    139A  LYS*     2.9    38.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 136 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    112A  ASN*     4.5    11.7    -      -       +      +
    115A  ASP*     3.8    42.2    -      -       +      +
    116A  VAL*     3.8    28.7    -      -       +      +
    119A  LEU*     4.3    15.0    -      -       +      -
    132A  MSE      2.9    31.8    +      -       +      +
    133A  GLY*     3.5     7.9    -      -       -      +
    135A  LYS*     1.3    75.5    -      -       +      +
    137A  GLU*     1.3    60.2    +      -       -      +
    139A  LYS*     2.8    24.8    +      -       +      +
    140A  VAL*     2.8    35.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 137 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    133A  GLY      2.6    22.2    +      -       -      +
    134A  LYS*     3.6    22.3    +      -       -      +
    136A  LEU*     1.3    73.4    -      -       -      +
    138A  LYS*     1.3    60.4    +      -       -      +
    140A  VAL*     3.1    17.5    -      -       +      +
    141A  LYS*     2.9    53.9    +      -       -      +
----------------------------------------------------------
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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
----------------------------------------------------------
    134A  LYS      2.9    13.5    +      -       -      +
    135A  LYS*     3.1    14.6    -      -       -      +
    137A  GLU*     1.3    77.8    -      -       -      +
    139A  LYS*     1.3    58.6    +      -       +      +
    141A  LYS*     3.4     9.5    +      -       -      +
    142A  TYR*     3.0    28.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 139 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    111A  LEU*     5.0    12.1    -      -       -      +
    112A  ASN*     3.9    30.4    -      -       -      +
    115A  ASP*     5.1     4.9    +      -       -      -
    135A  LYS*     2.9    22.9    +      -       -      +
    136A  LEU*     2.8    20.6    +      -       +      +
    138A  LYS*     1.3    75.5    -      -       +      +
    140A  VAL*     1.3    66.6    +      -       -      +
    142A  TYR*     3.1    12.0    +      -       +      +
    143A  PHE*     2.9    22.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 140 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    112A  ASN*     4.1    22.4    +      -       +      +
    116A  VAL*     5.3    10.3    -      -       +      -
    136A  LEU*     2.8    21.1    +      -       +      +
    137A  GLU*     3.1    26.0    -      -       +      +
    139A  LYS*     1.3    70.9    -      -       -      +
    141A  LYS*     1.3    80.2    +      -       +      +
    143A  PHE*     3.0    12.9    -      -       -      +
    144A  ASN*     2.9    21.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 141 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    137A  GLU*     2.9    58.0    +      -       +      +
    138A  LYS*     3.5     7.2    -      -       -      +
    139A  LYS      3.2     0.4    -      -       -      -
    140A  VAL*     1.3    86.8    -      -       +      +
    142A  TYR*     1.3    63.3    +      -       -      +
    144A  ASN*     3.0    19.3    +      -       -      +
    145A  GLU*     3.1    18.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 142 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    138A  LYS*     3.0    16.0    +      -       +      +
    139A  LYS*     3.4    13.2    -      -       +      +
    141A  LYS*     1.3    74.6    -      -       -      +
    143A  PHE*     1.3    66.2    +      -       -      +
    145A  GLU*     2.9    24.9    +      -       +      +
    146A  GLU*     3.0    47.0    +      -       +      +
    149A  ARG*     6.3     0.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with PHE 143 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    105A  LEU*     2.9    55.4    -      -       +      +
    108A  ALA*     3.8    17.7    -      -       +      -
    109A  TYR*     3.7    28.0    -      +       +      -
    112A  ASN*     5.0     5.8    -      -       -      +
    139A  LYS      2.9    12.6    +      -       -      +
    140A  VAL*     3.0    17.9    -      -       -      +
    142A  TYR*     1.3    80.2    -      -       -      +
    144A  ASN*     1.3    60.5    +      -       +      +
    146A  GLU*     3.0     8.9    +      -       -      +
    147A  ALA*     2.9    40.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 144 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    140A  VAL      2.9    11.0    +      -       -      +
    141A  LYS*     3.2    14.1    -      -       -      +
    143A  PHE*     1.3    81.3    -      -       +      +
    145A  GLU*     1.3    74.2    +      -       -      +
    147A  ALA*     4.0     4.7    -      -       -      +
    148A  GLU*     3.1    47.6    +      -       -      +
    114B  ARG*     3.2    29.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 145 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    141A  LYS*     3.4    15.7    -      -       +      +
    142A  TYR*     2.9    18.8    +      -       +      +
    144A  ASN*     1.3    88.2    -      -       -      +
    146A  GLU*     1.3    69.1    +      -       -      +
    148A  GLU*     3.5    10.1    +      -       -      +
    149A  ARG*     3.0    37.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 146 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    101A  ASN*     5.1     1.7    +      -       -      -
    105A  LEU*     4.0    16.5    -      -       +      +
    142A  TYR*     3.0    54.3    +      -       +      +
    143A  PHE*     3.4     8.1    -      -       -      +
    145A  GLU*     1.3    75.1    -      -       -      +
    147A  ALA*     1.3    66.1    +      -       -      +
    149A  ARG*     2.6    42.4    +      -       -      +
    150A  HIS*     3.0    35.9    +      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 147 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    105A  LEU*     4.1    22.8    -      -       +      +
    143A  PHE*     2.9    31.0    +      -       +      +
    144A  ASN*     4.0     7.4    -      -       -      +
    146A  GLU*     1.3    72.4    -      -       -      +
    148A  GLU*     1.3    62.7    +      -       +      +
    150A  HIS*     3.4     3.7    +      -       -      +
    151A  LEU*     3.1    23.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 148 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    144A  ASN*     3.1    35.3    +      -       -      +
    145A  GLU*     3.9     9.5    -      -       -      +
    147A  ALA*     1.3    78.1    -      -       +      +
    149A  ARG*     1.3    61.6    +      -       -      +
    151A  LEU*     3.3    11.3    +      -       +      +
    152A  GLU*     2.9    36.0    +      -       -      +
    114B  ARG*     2.5    33.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 149 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    145A  GLU*     3.0    23.6    +      -       -      +
    146A  GLU*     2.6    50.4    +      -       -      +
    148A  GLU*     1.3    74.7    -      -       -      +
    150A  HIS*     1.3    74.6    +      -       +      +
    152A  GLU*     3.1    11.7    +      -       +      +
    153A  THR*     3.0    26.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 150 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     97A  TYR*     4.3    13.4    -      +       -      -
     98A  GLU*     3.4    26.5    +      -       -      +
    101A  ASN*     2.7    45.0    +      -       -      +
    105A  LEU*     4.3     9.4    -      -       +      +
    146A  GLU*     3.0    48.9    +      -       +      +
    147A  ALA*     3.8     7.0    -      -       -      +
    149A  ARG*     1.3    83.2    +      -       +      +
    151A  LEU*     1.3    60.0    +      -       -      +
    153A  THR*     3.0    11.5    +      -       -      -
    154A  LEU*     3.0    31.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 151 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    147A  ALA      3.1    17.8    +      -       -      +
    148A  GLU*     3.7    10.1    -      -       +      +
    150A  HIS*     1.3    73.4    -      -       -      +
    152A  GLU*     1.3    66.9    +      -       -      +
    154A  LEU*     3.4    19.8    +      -       +      +
    155A  ASP*     3.1    46.3    +      -       -      +
    121B  ARG*     3.8    21.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 152 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     82A  LYS      5.2     4.6    -      -       -      +
    148A  GLU*     2.9    20.2    +      -       -      +
    149A  ARG*     3.2    14.6    -      -       -      +
    151A  LEU*     1.3    78.3    -      -       -      +
    153A  THR*     1.3    62.0    +      -       -      +
    155A  ASP*     3.4     6.3    +      -       -      +
    156A  GLY*     3.2    19.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with THR 153 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     79A  MSE      5.0    17.8    -      -       +      -
     82A  LYS      5.7     3.8    -      -       -      -
     84A  ALA*     5.4     0.9    -      -       -      +
     94A  LEU*     5.3     4.7    -      -       +      -
     98A  GLU*     3.7    23.2    +      -       +      +
    149A  ARG*     3.0    17.4    +      -       -      +
    150A  HIS*     3.0    14.3    +      -       -      -
    152A  GLU*     1.3    74.5    -      -       -      +
    154A  LEU*     1.3    68.1    +      -       -      +
    156A  GLY      3.1    13.3    +      -       -      -
    157A  MSE      3.5    20.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 154 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     95A  MSE      3.5    34.1    -      -       +      -
     98A  GLU*     3.7    24.9    -      -       +      +
    150A  HIS*     3.0    19.1    +      -       +      +
    151A  LEU*     3.4    21.1    +      -       +      +
    153A  THR*     1.3    76.6    -      -       -      +
    155A  ASP*     1.3    65.3    +      -       -      +
    157A  MSE      3.5    19.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 155 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    151A  LEU*     3.1    25.0    +      -       -      +
    152A  GLU*     3.8     6.7    -      -       -      +
    153A  THR      3.1     1.0    -      -       -      -
    154A  LEU*     1.3    80.4    -      -       -      +
    156A  GLY*     1.3    56.7    +      -       -      +
    157A  MSE      3.3     3.3    +      -       -      +
    158A  ASN*     5.1     3.5    +      -       -      -
    121B  ARG*     2.5    48.1    +      -       -      -
    123B  PHE*     3.9    23.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 156 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     82A  LYS      4.4     4.2    -      -       -      +
     83A  ASN*     3.4    26.0    -      -       -      +
     84A  ALA*     2.6    34.7    +      -       -      +
    152A  GLU      3.2    10.1    +      -       -      -
    153A  THR      3.1     8.6    +      -       -      -
    155A  ASP*     1.3    76.4    -      -       -      +
    157A  MSE      1.3    54.4    +      -       -      +
    158A  ASN*     3.9     2.0    -      -       -      -
----------------------------------------------------------
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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