Contacts of the helix formed by residues 266 - 292 (chain B) in PDB entry 2W5X


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 ASN 266 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    224B  GLU*     5.0     3.2    +      -       -      -
    261B  GLY      2.9     7.3    +      -       -      +
    264B  ALA*     3.9    19.8    -      -       +      +
    265B  ASN*     1.3    75.8    -      -       -      +
    267B  ALA*     1.3    64.6    +      -       -      +
    269B  TYR*     3.3    30.6    +      -       +      +
    270B  LEU*     3.0    22.0    +      -       -      +
    332B  PHE*     3.6     2.4    -      -       -      -
   1380B   MG      2.5    30.4    -      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 267 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    265B  ASN      3.9     1.4    +      -       -      -
    266B  ASN*     1.3    73.2    +      -       -      +
    268B  SER*     1.3    58.3    +      -       -      +
    270B  LEU*     3.3     3.1    +      -       -      +
    271B  ILE*     2.8    39.5    +      -       +      +
    307B  PHE*     4.5     3.1    -      -       +      -
    330B  PRO*     3.9    35.0    -      -       +      +
    332B  PHE*     3.9    17.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 268 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    224B  GLU*     2.6    25.8    +      -       -      +
    266B  ASN*     3.4     1.6    +      -       -      -
    267B  ALA*     1.3    78.5    -      -       -      +
    269B  TYR*     1.3    57.1    +      -       -      +
    271B  ILE*     4.1     6.6    -      -       -      +
    272B  SER*     2.9    33.1    +      -       -      -
   1380B   MG      2.5    26.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with TYR 269 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    222B  THR*     3.5    23.0    -      -       +      +
    224B  GLU*     4.2    12.6    -      -       +      +
    257B  GLN*     2.7    23.5    +      -       -      +
    260B  TRP*     3.3    32.1    -      -       +      +
    261B  GLY*     3.6    23.3    -      -       -      -
    264B  ALA*     5.0     3.8    -      -       +      -
    266B  ASN*     3.3    31.6    +      -       +      +
    268B  SER*     1.3    79.6    +      -       -      +
    270B  LEU*     1.3    65.2    +      -       -      +
    272B  SER*     3.0     7.9    +      -       -      -
    273B  GLU*     3.0    57.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 270 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     44B  GLY      5.8     0.2    -      -       -      +
     49B  GLN*     3.6    41.7    -      -       +      +
     52B  SER*     4.6     0.4    -      -       -      +
    258B  ILE*     4.1    17.8    -      -       +      +
    261B  GLY*     3.9    12.0    -      -       -      -
    262B  GLY*     4.0    15.3    -      -       -      +
    266B  ASN      3.0    16.9    +      -       -      +
    267B  ALA*     3.7     4.0    -      -       -      +
    269B  TYR*     1.3    76.0    -      -       -      +
    271B  ILE*     1.3    75.5    +      -       +      +
    273B  GLU*     3.3     4.3    +      -       -      +
    274B  ILE*     3.1    27.8    +      -       +      +
    307B  PHE*     3.8    28.0    -      -       +      -
    332B  PHE*     3.9    14.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 271 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     52B  SER*     4.0    18.6    -      -       -      +
     56B  PHE*     3.7    48.7    -      -       +      +
    267B  ALA*     2.8    31.0    +      -       +      +
    268B  SER*     4.1     5.6    -      -       -      +
    270B  LEU*     1.3    71.7    -      -       +      +
    272B  SER*     1.3    60.9    +      -       -      +
    274B  ILE*     3.4     6.9    +      -       -      +
    275B  ASN*     2.9    46.5    +      -       -      +
    307B  PHE*     4.3    17.7    -      -       +      -
    330B  PRO*     4.4     9.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 272 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    223B  MET*     3.7    21.7    -      -       -      +
    224B  GLU*     3.8    17.8    -      -       -      +
    268B  SER      2.9    22.6    +      -       -      -
    269B  TYR*     3.0    12.0    +      -       -      -
    271B  ILE*     1.3    77.6    -      -       -      +
    273B  GLU*     1.3    63.7    +      -       -      +
    275B  ASN*     3.5     9.0    +      -       -      +
    276B  ASP*     3.2    22.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 273 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    130B  THR*     4.9     0.3    +      -       -      -
    222B  THR*     3.5     6.8    -      -       -      -
    223B  MET*     2.8    35.7    +      -       -      +
    227B  ARG*     2.8    31.2    +      -       -      -
    255B  GLY*     5.7     1.4    -      -       -      -
    257B  GLN*     3.7    19.0    +      -       +      +
    258B  ILE*     3.8    22.3    -      -       +      +
    269B  TYR*     3.0    45.9    +      -       +      +
    270B  LEU      3.7     3.6    -      -       -      +
    272B  SER*     1.3    79.5    +      -       -      +
    274B  ILE*     1.3    58.5    +      -       -      +
    276B  ASP*     3.4     5.7    +      -       -      +
    277B  PHE*     3.1    23.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 274 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     45B  ALA*     3.8    22.9    -      -       +      -
     49B  GLN*     3.6    28.0    -      -       +      +
     50B  ILE*     3.7    11.0    -      -       -      +
     52B  SER*     3.7    20.6    -      -       -      +
     53B  THR*     4.0    11.2    -      -       +      +
     63B  TYR*     4.0    16.8    -      -       +      +
    258B  ILE*     3.7    21.7    -      -       +      +
    270B  LEU*     3.1    21.1    +      -       +      +
    271B  ILE*     3.5    11.4    -      -       -      +
    273B  GLU*     1.3    74.3    -      -       -      +
    275B  ASN*     1.3    62.9    +      -       -      +
    277B  PHE*     3.2     3.9    +      -       +      -
    278B  ASP*     2.9    27.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 275 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     53B  THR*     3.5    18.3    -      -       -      +
     56B  PHE      3.3    23.6    +      -       -      -
     57B  LYS*     3.4    43.2    +      -       +      +
    271B  ILE*     2.9    32.4    +      -       -      +
    272B  SER*     3.7     8.8    -      -       -      +
    274B  ILE*     1.3    76.3    -      -       -      +
    276B  ASP*     1.3    61.3    +      -       -      +
    278B  ASP*     3.2     5.1    +      -       -      +
    279B  ASP*     3.1    20.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with ASP 276 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    223B  MET*     3.5    35.0    -      -       +      +
    227B  ARG*     2.8    21.8    +      -       -      -
    228B  GLY      3.8     7.4    -      -       -      +
    229B  ASN*     4.4     9.2    -      -       -      +
    231B  LEU*     3.7    24.5    +      -       -      +
    232B  SER*     4.4     2.4    +      -       -      -
    272B  SER      3.2    10.6    +      -       -      +
    273B  GLU      3.5     8.9    -      -       -      +
    275B  ASN*     1.3    77.5    -      -       -      +
    277B  PHE*     1.3    64.5    +      -       -      +
    279B  ASP*     3.0    30.8    +      -       -      +
    280B  ALA*     3.1     7.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 277 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     40B  LEU*     3.7    30.3    -      -       +      -
     41B  ILE      3.4    24.5    -      -       -      -
     42B  SER*     3.5    26.9    -      -       -      -
     63B  TYR*     3.5    26.7    -      -       -      -
    231B  LEU*     4.0    13.9    -      -       +      -
    253B  SER      4.5     1.8    -      -       -      -
    255B  GLY*     3.7    23.1    -      -       -      -
    258B  ILE*     3.9     9.2    -      -       +      -
    273B  GLU      3.1    14.9    +      -       -      +
    274B  ILE*     3.4     9.6    -      -       +      +
    276B  ASP*     1.3    77.1    +      -       -      +
    278B  ASP*     1.3    58.7    +      -       -      +
    280B  ALA*     2.9    20.1    +      -       +      +
    281B  ILE*     3.0    28.6    +      -       +      +
    298B  VAL*     3.7     9.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASP 278 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     53B  THR*     4.5     3.8    -      -       +      -
     57B  LYS*     2.6    27.0    +      -       +      +
     61B  PRO*     3.5     8.6    -      -       -      +
     62B  ASN*     2.8    56.9    +      -       -      +
     63B  TYR*     3.1    32.0    +      -       +      -
    274B  ILE      2.9    13.7    +      -       -      +
    275B  ASN*     3.2    10.3    +      -       -      +
    277B  PHE*     1.3    76.2    -      -       -      +
    279B  ASP*     1.3    61.2    +      -       -      +
    281B  ILE*     3.2    12.9    +      -       -      +
    282B  GLY      3.1     8.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with ASP 279 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     57B  LYS*     2.8    25.7    +      -       -      +
     62B  ASN*     4.2     4.0    +      -       -      +
    229B  ASN*     5.7     5.0    -      -       +      +
    232B  SER*     3.3    14.0    +      -       -      +
    275B  ASN      3.1    14.0    +      -       -      +
    276B  ASP*     3.0    22.3    +      -       -      +
    278B  ASP*     1.3    77.1    -      -       -      +
    280B  ALA*     1.3    59.1    +      -       -      +
    282B  GLY*     3.1     4.3    +      -       -      -
    283B  THR*     3.1    18.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 280 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     40B  LEU*     4.1    12.9    -      -       +      +
    231B  LEU*     3.7    34.5    -      -       +      +
    232B  SER*     3.2    16.5    +      -       -      +
    235B  THR*     4.8     7.4    -      -       -      +
    276B  ASP      3.1     4.8    +      -       -      +
    277B  PHE*     2.9    12.9    +      -       +      +
    279B  ASP*     1.3    73.1    -      -       -      +
    281B  ILE*     1.3    66.4    +      -       -      +
    283B  THR*     3.1     7.3    +      -       -      -
    284B  ALA*     3.0    22.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 281 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     40B  LEU*     3.7    11.8    -      -       +      +
     62B  ASN*     3.9     9.9    -      -       +      +
     63B  TYR*     3.6    42.2    -      -       +      -
     66B  PHE*     3.7    26.5    -      -       +      -
    277B  PHE*     3.0    36.1    +      -       +      +
    278B  ASP*     3.2    13.4    +      -       -      +
    280B  ALA*     1.3    76.5    -      -       -      +
    282B  GLY*     1.3    63.4    +      -       -      +
    284B  ALA*     3.1     2.6    +      -       -      +
    285B  LEU*     2.9    36.1    +      -       +      +
    296B  VAL*     5.7     0.2    -      -       +      -
    298B  VAL*     3.8    16.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 282 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     62B  ASN*     3.4    30.4    -      -       -      +
     65B  GLN*     4.6     2.4    +      -       -      -
    278B  ASP      3.1    10.7    +      -       -      -
    279B  ASP      3.1     3.1    +      -       -      -
    281B  ILE*     1.3    75.7    -      -       -      +
    283B  THR*     1.3    56.8    +      -       -      +
    285B  LEU*     3.5     4.5    +      -       -      +
    286B  ALA*     2.9    31.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 283 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    232B  SER*     3.4    39.8    -      -       -      +
    235B  THR*     4.7     5.8    -      -       +      -
    236B  ASP*     4.0    28.2    -      -       +      +
    239B  ILE*     5.0     2.9    -      -       +      -
    279B  ASP      3.1     8.2    +      -       -      -
    280B  ALA*     3.1    12.5    +      -       -      -
    282B  GLY*     1.3    78.6    -      -       -      +
    284B  ALA*     1.3    62.6    +      -       -      +
    286B  ALA*     3.4     4.7    +      -       -      +
    287B  PHE*     3.2    21.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 284 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     38B  ILE*     4.2    24.2    -      -       +      +
     40B  LEU*     3.8    21.3    -      -       +      -
    235B  THR*     5.1     3.8    -      -       +      -
    239B  ILE*     4.8     4.5    -      -       -      -
    280B  ALA      3.0    12.2    +      -       -      +
    281B  ILE      3.7     6.3    -      -       -      +
    283B  THR*     1.3    78.2    -      -       -      +
    285B  LEU*     1.3    59.2    +      -       -      +
    287B  PHE*     3.4     4.3    +      -       -      +
    288B  ALA*     2.9    27.7    +      -       -      +
    296B  VAL*     3.9    18.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 285 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     62B  ASN      4.0     3.8    -      -       -      +
     65B  GLN*     3.6    50.9    -      -       +      +
     66B  PHE*     4.0    15.9    -      -       +      -
    281B  ILE*     2.9    37.1    +      -       +      +
    282B  GLY      4.0     2.7    -      -       -      +
    284B  ALA*     1.3    75.9    -      -       -      +
    286B  ALA*     1.3    60.5    +      -       -      +
    288B  ALA*     4.3     1.6    -      -       -      -
    289B  LYS*     2.9    39.0    +      -       +      +
    296B  VAL*     4.1    15.0    -      -       +      -
    347B  TYR*     3.9    36.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 286 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    282B  GLY      2.9    19.2    +      -       -      +
    283B  THR*     3.8     6.3    -      -       -      +
    284B  ALA      3.4     0.2    -      -       -      -
    285B  LEU*     1.3    77.1    -      -       -      +
    287B  PHE*     1.3    62.2    +      -       -      +
    289B  LYS*     3.7     4.3    +      -       -      +
    290B  LYS*     3.4    31.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 287 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     36B  ASN*     4.7     0.7    -      -       -      -
     38B  ILE*     4.5     2.2    -      -       +      -
    236B  ASP*     5.9     2.0    -      -       -      +
    239B  ILE*     3.5    42.4    -      -       +      -
    243B  SER*     5.1     7.0    -      -       -      -
    249B  PHE*     3.6    25.4    -      +       -      -
    283B  THR      3.2     9.9    +      -       -      +
    284B  ALA      3.7     5.8    -      -       -      +
    285B  LEU      3.2     0.6    -      -       -      -
    286B  ALA*     1.3    79.6    -      -       -      +
    288B  ALA*     1.3    59.9    +      -       -      +
    290B  LYS*     3.3    13.6    +      -       +      +
    291B  ASP*     2.8    55.9    +      -       +      +
    294B  THR*     3.2    28.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 288 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    284B  ALA      2.9    17.8    +      -       -      +
    285B  LEU*     3.2     5.4    +      -       -      +
    287B  PHE*     1.3    76.9    -      -       -      +
    289B  LYS*     1.3    58.7    +      -       -      +
    291B  ASP*     4.3     0.2    -      -       -      -
    292B  GLY*     2.8    30.7    +      -       -      -
    294B  THR*     3.8    31.9    +      -       +      +
    296B  VAL*     3.6    22.2    -      -       +      -
    347B  TYR*     4.4    13.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 289 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     65B  GLN*     3.0    40.6    +      -       -      +
    285B  LEU*     2.9    21.2    +      -       -      +
    286B  ALA*     4.2     4.3    -      -       -      +
    288B  ALA*     1.3    76.2    -      -       -      +
    290B  LYS*     1.3    59.6    +      -       -      +
    292B  GLY*     4.1     6.6    +      -       -      -
    347B  TYR*     3.2    47.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 290 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    286B  ALA*     3.4    22.8    +      -       -      +
    287B  PHE*     3.3    11.8    +      -       +      +
    288B  ALA      3.3     0.2    -      -       -      -
    289B  LYS*     1.3    78.9    -      -       -      +
    291B  ASP*     1.3    63.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 291 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     36B  ASN*     3.4     7.4    +      -       -      -
    287B  PHE*     2.8    45.5    +      -       +      +
    288B  ALA      3.9     1.1    -      -       -      +
    290B  LYS*     1.3    81.1    -      -       +      +
    292B  GLY*     1.3    57.2    +      -       -      +
    293B  ASN*     3.0    42.9    +      -       -      +
    294B  THR*     2.7    22.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 292 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     32B  LYS*     4.1     8.3    +      -       -      -
    288B  ALA      2.8    20.2    +      -       -      -
    289B  LYS      4.5     4.9    -      -       -      -
    290B  LYS      3.6     1.2    -      -       -      -
    291B  ASP*     1.3    71.7    -      -       -      +
    293B  ASN*     1.3    64.7    +      -       -      +
    294B  THR      3.6     2.7    -      -       -      -
    349B  PRO*     3.7    16.2    -      -       -      +
----------------------------------------------------------
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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