Contacts of the helix formed by residues 268 - 291 (chain B) in PDB entry 5A86


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 PRO 268 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    266B  ASP      3.8     2.2    -      -       -      +
    267B  LEU*     1.3    89.6    -      -       +      +
    269B  ILE*     1.3    66.0    +      -       -      +
    270B  GLU*     4.3    13.9    -      -       +      +
    271B  ASP*     3.1    25.2    +      -       -      +
    272B  GLN*     3.1    10.2    +      -       -      +
    357B  LEU*     6.2     1.6    -      -       +      -
    358B  GLN*     3.9    32.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 269 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    267B  LEU      3.7     1.4    +      -       -      -
    268B  PRO*     1.3    71.2    -      -       -      +
    270B  GLU*     1.3    94.3    +      -       -      +
    272B  GLN*     3.4    16.0    +      -       -      +
    273B  ILE*     3.1    25.1    +      -       +      +
    684D  THR*     3.9     8.7    -      -       +      -
    691D  HIS*     3.8    28.3    -      -       +      +
    694D  LEU*     3.6    41.7    -      -       +      -
    695D  GLN*     5.4     3.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 270 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    268B  PRO*     3.1    10.4    -      -       +      +
    269B  ILE*     1.3   104.7    +      -       -      +
    271B  ASP*     1.3    60.5    +      -       -      +
    273B  ILE*     3.4     8.5    +      -       -      +
    274B  SER*     3.0    30.7    +      -       -      +
    355B  GLY      5.4     2.5    -      -       -      +
    357B  LEU*     5.3    13.0    -      -       +      -
    682D  SER      5.7     2.2    -      -       -      +
    683D  LEU*     4.3    30.2    +      -       +      +
    684D  THR*     3.1    17.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 271 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    267B  LEU*     4.5    11.1    -      -       +      +
    268B  PRO*     3.1    21.6    +      -       +      +
    270B  GLU*     1.3    76.7    -      -       -      +
    272B  GLN*     1.4    56.9    -      -       -      +
    274B  SER*     3.7     4.6    -      -       -      -
    275B  LEU*     2.8    42.2    +      -       +      +
    355B  GLY      3.7     4.5    -      -       -      +
    356B  VAL*     3.4    16.2    -      -       +      +
    357B  LEU*     2.8    30.2    +      -       -      +
    358B  GLN*     2.9    41.1    +      -       -      +
    362B  VAL*     5.0     0.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 272 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    264B  PHE*     3.2    46.5    +      -       +      +
    265B  ARG*     3.1    22.6    +      -       -      +
    267B  LEU*     2.9    25.4    +      -       +      +
    268B  PRO      3.1    11.4    +      -       -      +
    269B  ILE*     3.4    23.3    -      -       -      +
    270B  GLU      3.3     0.2    -      -       -      -
    271B  ASP*     1.4    73.9    -      -       -      +
    273B  ILE*     1.3    62.4    +      -       -      +
    275B  LEU*     3.9     0.4    -      -       -      +
    276B  LEU*     3.0    31.5    +      -       -      +
    694D  LEU*     3.7    25.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 273 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    269B  ILE*     3.1    18.9    +      -       +      +
    270B  GLU*     3.5     7.6    -      -       -      +
    272B  GLN*     1.3    77.1    -      -       -      +
    274B  SER*     1.3    62.7    +      -       -      +
    276B  LEU*     3.3     5.2    +      -       -      +
    277B  LYS*     3.0    46.9    +      -       +      +
    683D  LEU*     4.2    13.9    -      -       +      +
    684D  THR*     4.0    37.7    -      -       +      +
    687D  HIS*     4.1    24.9    -      -       +      +
    690D  LEU*     4.2    12.9    -      -       +      +
    691D  HIS*     4.7     9.2    -      -       -      +
    694D  LEU*     3.7    18.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 274 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    270B  GLU*     3.0    17.5    +      -       -      +
    271B  ASP*     3.2     5.8    +      -       -      -
    273B  ILE*     1.3    77.2    -      -       -      +
    275B  LEU*     1.3    63.5    +      -       -      +
    277B  LYS*     3.5     9.0    +      -       -      +
    278B  GLY*     3.2    19.1    +      -       -      -
    353B  ARG*     4.2     8.1    -      -       -      +
    354B  PRO      3.9    17.6    +      -       -      +
    355B  GLY*     3.4    26.8    +      -       -      -
    356B  VAL*     4.1     8.7    -      -       -      -
    683D  LEU*     4.3    13.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 275 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    264B  PHE*     4.1    17.3    -      -       +      -
    267B  LEU*     3.5    32.5    -      -       +      -
    271B  ASP*     2.8    23.5    +      -       +      +
    272B  GLN      3.9     3.1    -      -       -      +
    274B  SER*     1.3    72.2    -      -       -      +
    276B  LEU*     1.3    56.4    +      -       -      +
    278B  GLY*     3.3     2.4    +      -       -      -
    279B  ALA*     3.0    32.1    +      -       -      +
    348B  LEU*     3.5    26.2    -      -       +      +
    349B  PHE*     4.5     7.2    -      -       +      -
    350B  SER      3.4    27.4    -      -       -      +
    353B  ARG*     4.2     6.4    +      -       +      -
    356B  VAL*     3.8    16.8    -      -       +      -
    362B  VAL*     4.3    13.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 276 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    254B  ILE*     4.2    14.4    -      -       +      +
    255B  ILE*     4.0    33.7    -      -       +      -
    258B  ALA*     3.9    21.5    -      -       +      -
    264B  PHE*     3.9    17.7    -      -       +      -
    272B  GLN      3.0    21.3    +      -       -      +
    273B  ILE*     3.3     4.9    +      -       -      +
    275B  LEU*     1.3    73.0    -      -       -      +
    277B  LYS*     1.3    61.2    +      -       -      +
    279B  ALA      4.5     0.4    -      -       -      +
    280B  ALA*     2.9    37.6    +      -       +      +
    348B  LEU*     4.3     9.4    -      -       +      -
    428B  LEU*     4.3    10.8    -      -       +      -
    690D  LEU*     4.9     7.9    -      -       +      -
    694D  LEU*     3.9    25.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 277 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    273B  ILE*     3.0    33.1    +      -       +      +
    274B  SER*     3.8     8.1    -      -       -      +
    276B  LEU*     1.3    77.4    -      -       -      +
    278B  GLY*     1.3    62.7    +      -       -      +
    279B  ALA      3.5     0.2    +      -       -      -
    280B  ALA*     4.1     5.9    +      -       -      +
    281B  PHE      5.4     0.5    +      -       -      -
    354B  PRO      6.1     1.3    -      -       -      -
    404B  ASN*     5.3     1.2    +      -       -      -
    427B  GLU      3.0    23.3    +      -       -      +
    428B  LEU*     3.5    33.6    +      -       -      +
    429B  PHE*     4.7     7.6    -      -       -      -
    430B  GLY*     4.0    12.1    -      -       -      +
    683D  LEU*     4.9     5.6    -      -       +      -
    687D  HIS*     3.3    26.2    +      -       +      +
    690D  LEU*     4.1    15.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 278 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    274B  SER      3.2     9.8    +      -       -      -
    275B  LEU      3.7     2.9    -      -       -      -
    277B  LYS*     1.3    81.9    -      -       -      +
    279B  ALA*     1.3    57.6    +      -       -      +
    353B  ARG*     3.1    35.2    +      -       -      -
    354B  PRO*     6.0     2.7    -      -       -      -
    404B  ASN*     3.0    24.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 279 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    254B  ILE*     5.3     0.7    -      -       -      -
    275B  LEU      3.0    16.2    +      -       -      +
    276B  LEU*     4.7     0.7    -      -       -      +
    278B  GLY*     1.3    78.7    -      -       -      +
    280B  ALA*     1.3    64.2    +      -       -      +
    281B  PHE      3.3     2.9    -      -       -      -
    282B  GLU*     3.1     6.4    +      -       -      +
    283B  LEU*     2.9    30.2    +      -       +      +
    347B  SER*     3.7    18.4    -      -       -      +
    348B  LEU*     4.0    15.5    -      -       +      -
    353B  ARG*     3.5    18.6    -      -       -      +
----------------------------------------------------------
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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
----------------------------------------------------------
    251B  PHE*     3.7    24.5    -      -       +      +
    254B  ILE*     4.4    14.6    -      -       +      +
    255B  ILE*     6.4     1.3    -      -       +      -
    276B  LEU*     2.9    21.0    +      -       +      +
    277B  LYS      4.1     4.4    +      -       -      +
    278B  GLY      3.8     1.2    -      -       -      -
    279B  ALA*     1.3    73.5    -      -       -      +
    281B  PHE*     1.3    62.3    +      -       -      +
    283B  LEU*     3.6     1.0    +      -       -      +
    284B  CYS*     3.0    29.1    +      -       -      -
    428B  LEU*     4.1    21.8    -      -       +      -
    429B  PHE*     5.1     2.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 281 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    251B  PHE*     4.0    12.0    -      +       -      -
    277B  LYS      5.4     0.8    +      -       -      -
    279B  ALA      3.3     0.6    -      -       -      -
    280B  ALA*     1.3    76.5    -      -       -      +
    282B  GLU*     1.3    62.8    +      -       +      +
    284B  CYS*     3.3     3.9    +      -       +      +
    285B  GLN*     3.0    56.6    +      -       +      +
    323B  MET*     4.0    20.2    -      -       +      -
    400B  LEU*     4.4     4.5    -      -       +      -
    403B  ILE*     4.2     3.4    -      -       +      -
    404B  ASN*     3.3    54.2    -      -       +      +
    407B  HIS*     3.3    42.2    -      +       +      -
    429B  PHE*     4.4    15.6    -      +       +      -
   1432B  D7E      3.4    23.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 282 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    278B  GLY      4.2     0.2    -      -       -      -
    279B  ALA      3.1     5.1    +      -       -      +
    281B  PHE*     1.3    78.1    -      -       +      +
    283B  LEU*     1.3    62.6    +      -       -      +
    285B  GLN*     3.3     1.6    +      -       -      -
    286B  LEU*     3.0    27.9    +      -       -      +
    347B  SER*     2.8    35.0    +      -       -      +
    353B  ARG*     2.8    36.1    +      -       -      -
    397B  LEU*     4.9     3.8    -      -       -      +
    400B  LEU*     3.7    30.2    -      -       +      +
    401B  ARG*     3.5    25.2    +      -       -      +
    404B  ASN*     3.0    27.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 283 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    254B  ILE*     3.6    33.7    -      -       +      -
    257B  PHE*     3.9    23.6    -      -       +      -
    279B  ALA*     2.9    23.7    +      -       +      +
    280B  ALA      4.2     0.2    -      -       -      +
    282B  GLU*     1.3    72.0    -      -       -      +
    284B  CYS*     1.3    62.2    +      -       -      +
    286B  LEU*     3.3     8.3    +      -       +      +
    287B  ARG*     3.1    26.5    +      -       -      +
    344B  GLN*     3.4    48.5    -      -       +      +
    347B  SER*     3.3    25.6    -      -       -      +
    348B  LEU*     4.0    12.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with CYS 284 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    247B  SER*     5.9     0.2    -      -       -      -
    250B  MET*     3.6    27.1    -      -       +      +
    251B  PHE*     2.9    42.2    -      -       +      -
    254B  ILE*     3.6    15.7    -      -       -      -
    280B  ALA      3.0    19.2    +      -       -      +
    281B  PHE*     3.4     5.6    -      -       -      +
    283B  LEU*     1.3    75.6    -      -       -      +
    285B  GLN*     1.3    59.6    +      -       -      +
    287B  ARG*     3.2     7.0    +      -       -      +
    288B  PHE*     2.8    40.5    +      -       +      -
----------------------------------------------------------
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Residues in contact with GLN 285 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    281B  PHE*     3.0    44.8    +      -       +      +
    282B  GLU      3.3     4.5    +      -       -      +
    284B  CYS*     1.3    76.3    -      -       -      +
    286B  LEU*     1.3    60.7    +      -       -      +
    288B  PHE*     3.3    19.0    +      -       -      -
    289B  ASN*     2.9    26.0    +      -       -      +
    323B  MET*     3.6    17.9    -      -       +      +
    326B  PHE*     5.2     2.8    -      -       +      -
    327B  HIS*     2.9    37.0    +      -       -      -
    400B  LEU*     4.4     8.3    -      -       +      -
   1432B  D7E      3.2    48.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 286 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    282B  GLU      3.0    21.9    +      -       -      +
    283B  LEU*     3.6     9.6    -      -       +      +
    284B  CYS      3.3     0.2    -      -       -      -
    285B  GLN*     1.3    74.6    -      -       -      +
    287B  ARG*     1.3    62.7    +      -       -      +
    289B  ASN*     3.3    16.8    +      -       -      +
    290B  THR*     3.6    13.0    -      -       -      +
    326B  PHE*     4.4     2.0    -      -       +      -
    330B  LEU*     3.9    15.9    -      -       +      -
    340B  TYR*     3.8    10.6    -      -       +      -
    343B  MET*     3.5    39.9    -      -       +      +
    344B  GLN*     3.8    45.3    -      -       +      +
    347B  SER*     4.7     1.6    -      -       -      -
    397B  LEU*     4.4     7.9    -      -       +      -
    400B  LEU*     4.0    17.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 287 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    158B  GLN*     2.8    27.0    +      -       -      -
    161B  THR*     2.9    44.1    +      -       -      -
    162B  PHE*     3.6    46.4    -      -       +      +
    250B  MET*     3.7    19.1    +      -       +      +
    253B  GLY*     3.4    21.6    +      -       -      -
    254B  ILE*     3.3    24.3    -      -       +      +
    257B  PHE*     3.6    11.9    -      -       -      +
    283B  LEU      3.1    11.2    +      -       -      +
    284B  CYS      3.2     8.3    +      -       -      +
    286B  LEU*     1.3    73.2    -      -       -      +
    288B  PHE*     1.3    63.3    +      -       -      +
    290B  THR*     2.7    26.9    +      -       -      -
    291B  VAL*     3.8     2.6    +      -       -      +
    344B  GLN*     3.5    17.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 288 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    166B  PHE*     4.4     3.6    -      +       -      -
    246B  MET*     4.0    17.5    -      -       +      -
    247B  SER*     5.7     4.3    -      -       -      -
    250B  MET*     3.4    42.6    -      -       +      -
    284B  CYS*     2.8    26.7    +      -       +      +
    285B  GLN*     3.3    22.6    +      -       -      +
    287B  ARG*     1.3    75.4    -      -       -      +
    289B  ASN*     1.3    64.0    +      -       -      +
    291B  VAL*     3.0    29.6    +      -       +      +
    292B  PHE      3.2     8.5    +      -       -      -
    299B  TRP*     3.4    17.1    -      +       +      +
    301B  CYS*     4.3    12.1    -      -       -      -
    327B  HIS*     4.0     6.7    -      -       +      -
   1432B  D7E      3.5    46.4    -      +       +      -
----------------------------------------------------------
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Residues in contact with ASN 289 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    285B  GLN      2.9    13.8    +      -       -      +
    286B  LEU      3.5    11.4    -      -       -      +
    287B  ARG      3.2     0.4    -      -       -      -
    288B  PHE*     1.3    77.4    -      -       -      +
    290B  THR*     1.3    59.8    +      -       -      +
    292B  PHE*     3.1    16.0    +      -       -      +
    326B  PHE*     5.5     0.2    -      -       +      -
    327B  HIS*     2.9    55.4    +      -       +      +
    330B  LEU*     3.4    28.3    -      -       +      +
    331B  LYS*     3.3    21.9    +      -       -      +
    340B  TYR*     2.6    26.1    +      -       +      -
----------------------------------------------------------
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Residues in contact with THR 290 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    158B  GLN*     5.8     3.4    -      -       -      +
    162B  PHE*     3.4    20.8    -      -       +      -
    164B  THR*     5.8     0.2    -      -       -      +
    286B  LEU      3.6    15.3    -      -       -      +
    287B  ARG*     2.7    18.7    +      -       -      +
    289B  ASN*     1.3    75.0    -      -       -      +
    291B  VAL*     1.3    61.1    +      -       -      +
    331B  LYS*     3.6    14.4    +      -       -      +
    337B  GLU*     5.0    11.9    -      -       -      +
    340B  TYR*     3.7    38.8    -      -       +      -
    344B  GLN*     6.0     0.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 291 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    162B  PHE*     4.5     9.4    -      -       +      -
    164B  THR*     4.4    12.8    -      -       -      +
    166B  PHE*     4.4    15.7    -      -       +      -
    287B  ARG      4.3     0.4    -      -       -      +
    288B  PHE*     3.0    28.1    +      -       +      +
    290B  THR*     1.3    87.7    +      -       -      +
    292B  PHE*     1.3    60.6    +      -       -      +
    293B  ASN      3.7     1.2    +      -       -      -
    299B  TRP*     4.4     2.9    -      -       +      -
    300B  GLU*     2.8    54.9    +      -       -      +
    301B  CYS*     4.1    19.7    -      -       -      -
    331B  LYS*     4.9     0.2    -      -       -      -
----------------------------------------------------------
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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