Contacts of the helix formed by residues 283 - 308 (chain A) in PDB entry 5Q1B


Residue contacts within the protein are derived with the CSU software (Sobolev V., Sorokine A., Prilusky J., Abola E.E. and Edelman M. (1999) Automated analysis of interatomic contacts in proteins. Bioinformatics, 15, 327-332). A short description of the analytical approach is given at the end of the page.
For CSU analysis of other PDB entry

Note:
Non-standard 3 letter residue codes indicate a heterogroup. To identify and analyse, use LPC software

Legend:
Dist - nearest distance (Å) between atoms of two residues
Surf - contact surface area (Å2) between two residues
HB   - hydrophilic-hydrophilic contact (hydrogen bond)
Arom - aromatic-aromatic contact
Phob - hydrophobic-hydrophobic contact
DC   - hydrophobic-hydrophilic contact (destabilizing contact)
+/-  - indicates presence/absence of a specific contacts
*    - indicates residues forming contacts  by their side chain
       (including CA atoms)
Residues in contact with SER 283 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    282A  PHE*     1.3    77.1    -      -       -      +
    284A  ALA*     1.3    59.5    +      -       -      +
    285A  GLU*     3.6    10.0    +      -       -      +
    286A  GLU*     2.8    38.0    +      -       -      +
    287A  ASN*     3.0    26.5    +      -       -      -
    358A  ASN      5.7     0.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 284 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    283A  SER*     1.3    73.7    -      -       -      +
    285A  GLU*     1.4    57.2    +      -       +      +
    287A  ASN*     3.4     0.9    +      -       -      +
    288A  PHE      2.9    23.6    +      -       -      -
    358A  ASN      5.4     1.9    +      -       -      +
    359A  SER      3.4    20.4    -      -       -      +
    360A  GLY*     3.8    13.7    -      -       -      -
    458A  TRP*     3.3    10.2    +      -       -      -
    459A  ARG*     3.4    35.7    -      -       +      +
    460A  VAL*     3.4     4.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 285 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    283A  SER*     3.2     9.1    +      -       -      +
    284A  ALA*     1.4    76.0    -      -       +      +
    286A  GLU*     1.4    62.7    +      -       +      +
    288A  PHE*     3.6     3.5    +      -       -      +
    289A  LEU*     3.3    21.8    +      -       -      +
    459A  ARG      5.2     1.3    -      -       -      +
    460A  VAL*     3.6    19.3    -      -       +      -
    461A  ASN*     3.1    47.7    +      -       -      +
    462A  ASP      5.4     1.8    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 286 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    281A  ALA      4.9     0.3    -      -       -      +
    282A  PHE*     3.4    32.3    -      -       +      -
    283A  SER*     2.8    39.1    +      -       -      +
    285A  GLU*     1.4    75.5    -      -       +      +
    287A  ASN*     1.4    56.4    +      -       -      +
    289A  LEU*     3.4     9.3    +      -       -      +
    290A  ILE*     3.0    33.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 287 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    277A  ILE*     5.6     6.6    -      -       -      +
    282A  PHE*     3.3    31.0    +      -       -      +
    283A  SER      3.0    20.9    +      -       -      +
    284A  ALA      3.6     0.2    -      -       -      +
    285A  GLU      3.3     0.2    -      -       -      -
    286A  GLU*     1.4    74.5    -      -       -      +
    288A  PHE*     1.4    58.7    +      -       -      +
    290A  ILE*     3.2    10.9    +      -       -      +
    291A  LEU*     2.9    24.6    +      -       -      +
    355A  ARG      4.9     3.0    +      -       -      -
    358A  ASN      4.3     2.2    +      -       -      -
    359A  SER*     3.3    42.2    +      -       -      +
    458A  TRP*     4.4     2.5    -      -       +      -
    501A  9N7      3.4    28.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 288 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    284A  ALA      2.9    16.9    +      -       -      +
    285A  GLU      3.9     3.8    -      -       -      +
    286A  GLU      3.5     0.2    -      -       -      -
    287A  ASN*     1.4    74.4    -      -       -      +
    289A  LEU*     1.4    59.1    +      -       -      +
    291A  LEU*     3.2    10.8    +      -       +      +
    292A  THR*     3.0    39.1    +      -       +      +
    455A  LEU*     4.0    31.2    -      -       +      -
    458A  TRP*     3.7    32.0    -      +       +      +
    460A  VAL*     3.8    12.6    -      -       +      -
    462A  ASP      4.4     8.1    -      -       -      -
    463A  HIS*     3.8    15.0    -      +       +      -
    464A  LYS*     3.5    33.4    -      -       +      -
    465A  PHE*     3.7    27.8    -      +       -      -
----------------------------------------------------------
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Residues in contact with LEU 289 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    285A  GLU      3.3    12.6    +      -       -      +
    286A  GLU*     3.5    13.9    -      -       -      +
    288A  PHE*     1.4    79.1    -      -       -      +
    290A  ILE*     1.4    64.4    +      -       +      +
    292A  THR*     2.9    25.7    +      -       -      +
    293A  GLU*     3.1    15.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 290 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    276A  LYS*     4.4    24.9    -      -       +      +
    277A  ILE*     5.1     8.7    -      -       +      -
    282A  PHE*     3.8    40.8    -      -       +      -
    286A  GLU*     3.0    25.0    +      -       +      +
    287A  ASN*     3.5    12.3    -      -       -      +
    289A  LEU*     1.4    75.6    -      -       +      +
    291A  LEU*     1.4    52.9    +      -       -      +
    293A  GLU*     3.2     7.4    +      -       -      +
    294A  MET*     2.8    63.7    +      -       +      +
    501A  9N7      3.9    16.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 291 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    287A  ASN      2.9    13.8    +      -       -      +
    288A  PHE*     3.3    18.8    -      -       +      +
    290A  ILE*     1.4    76.7    -      -       -      +
    292A  THR*     1.3    56.0    +      -       +      +
    294A  MET*     3.4     2.2    +      -       -      +
    295A  ALA*     2.9    34.1    +      -       +      +
    332A  MET*     4.6    12.3    -      -       +      -
    455A  LEU*     3.8    28.9    -      -       +      -
    458A  TRP*     4.0    25.8    -      -       +      -
    473A  TRP*     4.3     6.1    -      -       +      -
    501A  9N7      3.8    60.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with THR 292 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    288A  PHE*     3.0    30.8    +      -       +      +
    289A  LEU*     2.9    31.0    +      -       -      +
    291A  LEU*     1.3    73.0    -      -       +      +
    293A  GLU*     1.3    55.0    +      -       -      +
    295A  ALA*     4.5     1.6    -      -       -      -
    296A  THR*     2.6    38.1    +      -       -      -
    464A  LYS      3.9    22.2    +      -       -      +
    465A  PHE*     4.8     1.8    -      -       +      -
    466A  THR*     5.5     6.5    -      -       -      +
    469A  LEU*     3.4    23.3    -      -       +      +
    473A  TRP*     4.5    11.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 293 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    268A  ARG*     3.1    40.4    +      -       -      -
    276A  LYS*     6.2     0.2    -      -       -      -
    289A  LEU*     3.1    20.2    +      -       +      +
    290A  ILE*     3.6     6.5    -      -       -      +
    292A  THR*     1.3    73.9    +      -       -      +
    294A  MET*     1.4    75.2    +      -       -      +
    296A  THR*     3.3     6.4    +      -       -      -
    297A  ASN*     3.2    20.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with MET 294 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    268A  ARG*     3.2    31.4    +      -       -      +
    272A  GLU*     5.5     2.0    -      -       -      +
    273A  ILE*     4.0    20.4    -      -       +      +
    276A  LYS*     4.2    26.9    -      -       +      -
    277A  ILE*     6.0     0.7    -      -       +      -
    290A  ILE*     2.8    41.6    +      -       +      +
    291A  LEU*     3.6     4.5    -      -       +      +
    293A  GLU*     1.4    80.4    +      -       -      +
    295A  ALA*     1.3    55.7    +      -       -      +
    297A  ASN*     3.4     4.2    +      -       -      +
    298A  HIS*     2.9    29.3    +      -       -      +
    501A  9N7      3.4    52.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 295 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    291A  LEU*     2.9    17.1    +      -       +      +
    292A  THR      4.0     1.3    -      -       -      +
    294A  MET*     1.3    72.7    -      -       -      +
    296A  THR*     1.3    65.6    +      -       -      +
    298A  HIS*     3.6     1.1    -      -       -      +
    299A  VAL*     3.0    31.0    +      -       +      +
    332A  MET*     3.7    24.6    -      -       +      -
    469A  LEU*     3.8     6.3    -      -       +      -
    473A  TRP*     3.5    35.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 296 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    292A  THR      2.6    24.3    +      -       -      -
    293A  GLU*     3.3     7.2    +      -       -      -
    295A  ALA*     1.3    76.5    -      -       -      +
    297A  ASN*     1.4    60.7    +      -       -      +
    299A  VAL*     3.5     3.9    +      -       -      +
    300A  GLN*     3.2    43.0    +      -       -      +
    466A  THR*     3.7    18.4    +      -       +      +
    468A  LEU*     4.3    13.4    -      -       +      +
    469A  LEU*     3.4    20.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 297 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    268A  ARG*     3.4    50.9    +      -       -      +
    293A  GLU*     3.2    12.5    +      -       -      +
    294A  MET      3.8     6.1    -      -       -      +
    296A  THR*     1.4    74.1    -      -       -      +
    298A  HIS*     1.4    58.8    +      -       -      +
    300A  GLN*     3.2    17.9    +      -       -      +
    301A  VAL*     2.9    43.8    +      -       -      +
    501A  9N7      4.1     6.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 298 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    267A  GLN*     4.3    14.2    +      -       -      -
    294A  MET      2.9    18.1    +      -       -      +
    295A  ALA*     3.6     9.0    -      -       -      +
    296A  THR      3.4     0.4    -      -       -      -
    297A  ASN*     1.4    75.7    +      -       -      +
    299A  VAL*     1.3    67.4    +      -       +      +
    301A  VAL*     3.3     5.9    +      -       -      +
    302A  LEU*     2.9    38.1    +      -       +      +
    328A  ALA      3.9     7.1    +      -       -      -
    331A  ALA*     3.6    18.5    -      -       +      +
    332A  MET*     3.3    50.4    +      -       +      -
    335A  ARG*     4.2     9.2    -      -       +      -
    501A  9N7      3.4    29.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 299 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    295A  ALA*     3.0    20.3    +      -       +      +
    296A  THR*     4.0     3.6    -      -       -      +
    298A  HIS*     1.3    78.8    -      -       +      +
    300A  GLN*     1.3    65.4    +      -       -      +
    302A  LEU*     3.6     5.6    -      -       -      +
    303A  VAL*     3.0    34.6    +      -       +      +
    324A  LEU*     4.7     4.3    -      -       +      -
    328A  ALA*     4.4     9.9    -      -       +      +
    332A  MET*     6.2     1.6    -      -       +      -
    468A  LEU*     4.7    15.5    -      -       +      -
    469A  LEU*     4.8     5.4    -      -       +      -
    472A  ILE*     3.6    49.8    -      -       +      -
    473A  TRP*     5.8     0.7    -      -       -      +
    749B  LEU*     4.7     4.5    -      -       +      -
    752B  LEU*     5.7     0.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLN 300 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    296A  THR*     3.2    33.1    +      -       -      +
    297A  ASN*     3.2    21.4    +      -       -      +
    299A  VAL*     1.3    78.5    -      -       -      +
    301A  VAL*     1.3    61.5    +      -       +      +
    303A  VAL*     3.4     9.2    +      -       -      +
    304A  GLU*     3.5    17.7    +      -       -      +
    468A  LEU*     3.8    18.2    -      -       +      +
    752B  LEU*     4.4    18.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 301 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    263A  SER      5.8     1.1    -      -       -      +
    266A  LYS*     4.4    15.5    -      -       +      +
    267A  GLN*     3.7    42.2    -      -       +      +
    268A  ARG      5.3     2.2    -      -       -      +
    297A  ASN*     2.9    36.8    +      -       -      +
    298A  HIS*     3.9     5.6    -      -       -      +
    300A  GLN*     1.3    74.3    -      -       +      +
    302A  LEU*     1.4    57.5    +      -       -      +
    304A  GLU*     3.3     9.8    +      -       +      +
    305A  PHE*     3.0    28.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 302 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    267A  GLN*     5.6     4.9    -      -       -      +
    298A  HIS*     2.9    31.2    +      -       +      +
    299A  VAL*     3.6     7.2    -      -       -      +
    300A  GLN      3.3     0.2    -      -       -      -
    301A  VAL*     1.4    73.9    -      -       -      +
    303A  VAL*     1.3    56.2    +      -       -      +
    305A  PHE*     3.3     8.8    +      -       +      +
    306A  THR*     2.7    44.2    +      -       -      +
    324A  LEU*     4.5    12.3    -      -       +      -
    327A  SER*     4.7     6.3    -      -       -      +
    328A  ALA*     3.7    35.7    -      -       +      +
    331A  ALA*     3.8    25.1    -      -       +      -
    390A  THR*     4.3     9.0    -      -       +      -
    394A  ILE*     3.9    20.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 303 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    299A  VAL*     3.0    26.7    +      -       +      +
    300A  GLN      3.9     5.4    -      -       -      +
    301A  VAL      3.4     0.6    -      -       -      -
    302A  LEU*     1.3    72.6    -      -       -      +
    304A  GLU*     1.3    60.9    +      -       -      +
    306A  THR*     3.2     7.6    +      -       -      -
    307A  LYS*     2.9    42.1    +      -       +      +
    324A  LEU*     3.8    25.6    -      -       +      -
    749B  LEU*     4.6     4.9    -      -       +      -
    752B  LEU*     3.8    50.7    -      -       +      +
    753B  LEU*     3.9    16.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 304 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    300A  GLN      3.5    11.0    +      -       -      +
    301A  VAL*     3.3    11.7    +      -       -      +
    303A  VAL*     1.3    79.8    -      -       -      +
    305A  PHE*     1.4    60.1    +      -       -      +
    307A  LYS*     3.6    23.1    +      -       -      +
    308A  LYS*     3.3    51.0    +      -       -      +
    752B  LEU*     4.5     2.1    -      -       -      +
    755B  LYS*     3.3    26.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with PHE 305 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    260A  ILE*     3.8    30.7    -      -       +      -
    263A  SER*     3.8    16.9    -      -       -      +
    264A  TYR*     3.8    34.5    -      +       -      -
    267A  GLN*     6.5     0.9    -      -       +      -
    301A  VAL*     3.0    17.0    +      -       +      +
    302A  LEU*     3.3    12.1    +      -       +      +
    304A  GLU*     1.4    74.9    -      -       -      +
    306A  THR*     1.3    62.6    +      -       -      +
    308A  LYS*     3.2    18.4    +      -       -      +
    309A  LEU*     3.4    31.2    +      -       +      +
    387A  ALA      3.7    21.8    -      -       -      -
    390A  THR*     4.1    12.6    -      -       +      -
    391A  ALA*     4.1     4.5    -      -       +      -
    394A  ILE*     3.7    31.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 306 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    302A  LEU*     2.7    24.8    +      -       -      +
    303A  VAL*     3.4     6.7    -      -       -      +
    305A  PHE*     1.3    76.1    -      -       -      +
    307A  LYS*     1.3    56.9    +      -       -      +
    309A  LEU*     3.0    32.5    +      -       -      +
    312A  PHE*     3.4    45.6    -      -       +      +
    324A  LEU*     4.0    16.0    -      -       +      +
    394A  ILE*     3.6    34.3    -      -       +      +
    753B  LEU*     5.0     0.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 307 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    303A  VAL*     2.9    28.1    +      -       +      +
    304A  GLU*     3.6    31.6    +      -       -      +
    305A  PHE      3.4     0.2    -      -       -      -
    306A  THR*     1.3    71.6    -      -       -      +
    308A  LYS*     1.3    60.3    +      -       +      +
    309A  LEU      3.3     5.1    +      -       -      +
    312A  PHE*     4.2     3.1    -      -       -      +
    313A  GLN*     3.0    47.3    +      -       -      +
    752B  LEU      3.0    24.8    +      -       -      +
    753B  LEU*     3.7    33.4    -      -       +      +
    755B  LYS*     3.0    32.2    +      -       -      +
    756B  ASP*     4.9     2.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 308 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    259A  PHE*     3.1    36.2    -      -       +      -
    260A  ILE*     5.7     0.7    -      -       -      -
    263A  SER*     3.4    32.8    -      -       -      +
    266A  LYS*     5.7    11.2    -      -       -      +
    304A  GLU*     3.3    42.6    +      -       -      +
    305A  PHE*     3.2     9.7    +      -       -      +
    306A  THR      3.2     1.0    -      -       -      -
    307A  LYS*     1.3    76.6    -      -       +      +
    309A  LEU*     1.4    64.1    +      -       -      +
    310A  PRO*     3.4     1.9    -      -       -      +
----------------------------------------------------------
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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