Contacts of the helix formed by residues 296 - 319 (chain B) in PDB entry 1PTH


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 296 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    295B  LEU*     1.3    83.1    -      -       -      +
    297B  GLY*     1.3    50.2    +      -       -      +
    299B  MET*     4.1     9.1    -      -       +      +
    300B  LEU*     2.7    38.1    +      -       -      +
    407B  PHE*     3.2    61.0    -      -       +      +
    409B  PHE      5.6     0.2    -      -       -      -
    410B  ASN*     4.4    13.9    -      -       +      +
    413B  MET*     4.3    23.8    -      -       +      -
    414B  LEU*     4.6    13.2    -      -       +      +
    422B  LEU*     4.7     8.1    -      -       +      -
    426B  PHE*     4.9     1.8    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLY 297 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    200B  PHE*     3.8    39.3    -      -       -      -
    295B  LEU      2.7     6.3    +      -       -      -
    296B  PRO*     1.3    80.6    -      -       -      +
    298B  LEU*     1.3    62.9    +      -       -      +
    300B  LEU*     3.1    13.7    -      -       -      +
    301B  TYR*     3.3    12.1    +      -       -      -
    407B  PHE*     4.1     4.9    -      -       -      -
    426B  PHE*     4.1     9.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 298 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    200B  PHE*     4.3     4.7    -      -       +      +
    203B  GLN*     3.2    39.9    -      -       +      +
    204B  HIS*     3.7    23.4    +      -       +      +
    207B  HIS*     5.9     2.0    -      -       +      -
    291B  VAL*     5.1     5.6    -      -       +      +
    292B  PHE*     3.5    46.7    -      -       +      +
    294B  LEU*     5.1     2.9    -      -       +      +
    295B  LEU*     2.7    39.5    +      -       +      +
    297B  GLY*     1.3    70.1    -      -       -      -
    299B  MET*     1.3    65.8    +      -       -      +
    300B  LEU      2.9     1.2    +      -       -      -
    301B  TYR*     3.0     6.6    +      -       -      +
    302B  ALA*     2.9    22.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with MET 299 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    263B  PRO*     4.5     2.0    -      -       -      -
    275B  TYR*     4.7     2.5    -      -       -      +
    285B  MET*     3.9    36.3    -      -       -      +
    287B  VAL*     3.7    30.7    -      -       +      -
    292B  PHE*     2.8    39.3    -      -       +      +
    293B  GLY*     3.5    15.3    -      -       -      +
    295B  LEU      3.3     7.3    +      -       -      +
    296B  PRO*     4.1     9.6    -      -       +      +
    298B  LEU*     1.3    79.3    -      -       -      +
    300B  LEU*     1.3    56.2    +      -       -      +
    302B  ALA*     3.6     4.5    -      -       +      +
    303B  THR*     2.9    31.4    +      -       -      +
    414B  LEU*     4.0    14.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 300 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    197B  MET*     4.6     5.6    -      -       -      -
    200B  PHE*     6.4     0.2    -      -       +      -
    296B  PRO      2.7    23.7    +      -       -      +
    297B  GLY*     3.1     9.0    -      -       -      +
    298B  LEU      2.9     0.2    +      -       -      -
    299B  MET*     1.3    74.6    -      -       -      +
    301B  TYR*     1.3    74.3    +      -       +      +
    303B  THR*     3.1    10.4    +      -       -      -
    304B  ILE*     3.1    24.0    +      -       +      +
    414B  LEU*     3.8    19.5    -      -       +      +
    419B  VAL*     3.7    45.1    -      -       +      +
    422B  LEU*     4.4     6.5    -      -       +      -
    423B  VAL*     3.7    20.2    -      -       +      -
    426B  PHE*     4.3    23.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 301 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    197B  MET*     2.8    51.5    +      -       +      +
    200B  PHE*     3.8    11.7    -      -       +      -
    201B  PHE*     3.2    59.5    -      +       -      +
    204B  HIS*     4.0    23.1    -      +       +      +
    297B  GLY      3.3    11.1    +      -       -      -
    298B  LEU      3.0     6.9    +      -       -      +
    300B  LEU*     1.3    84.3    -      -       +      +
    302B  ALA*     1.3    64.0    +      -       -      +
    304B  ILE*     2.9    22.3    +      -       +      +
    305B  TRP*     2.9    36.4    +      +       -      -
    426B  PHE*     6.5     0.4    -      +       -      -
    564B  LEU*     4.4    10.7    -      -       +      +
    567B  LEU*     5.4     3.8    -      -       +      -
    580B  PHE*     3.6     3.5    -      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 302 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    204B  HIS*     3.9    16.9    -      -       +      -
    232B  HIS      6.0     1.1    -      -       -      +
    233B  ILE*     5.8     3.8    -      -       -      +
    263B  PRO*     4.8     3.5    -      -       +      +
    287B  VAL*     4.6    21.9    -      -       +      +
    292B  PHE*     4.6     9.4    -      -       +      -
    298B  LEU      2.9    13.0    +      -       -      +
    299B  MET*     3.6    15.7    -      -       +      +
    300B  LEU      3.2     0.2    -      -       -      -
    301B  TYR*     1.3    77.0    -      -       -      +
    303B  THR*     1.3    56.9    +      -       -      +
    305B  TRP*     3.9     4.1    +      -       -      +
    306B  LEU*     3.1    27.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 303 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    261B  VAL      3.8     5.2    -      -       -      +
    262B  TYR*     3.8    10.2    -      -       +      -
    263B  PRO*     2.9    30.2    -      -       -      +
    299B  MET      2.9    13.1    +      -       -      -
    300B  LEU*     3.5     7.6    -      -       -      -
    301B  TYR      3.1     0.2    -      -       -      -
    302B  ALA*     1.3    75.0    -      -       -      +
    304B  ILE*     1.3    67.3    +      -       -      +
    306B  LEU*     3.1     6.2    +      -       -      +
    307B  ARG*     2.8    54.8    +      -       -      +
    414B  LEU*     3.9     6.4    -      -       -      +
    419B  VAL*     3.7    16.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 304 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    300B  LEU*     3.1    35.3    +      -       +      +
    301B  TYR*     2.9    22.6    +      -       +      +
    303B  THR*     1.3    75.7    -      -       +      +
    305B  TRP*     1.3    58.6    +      -       +      +
    307B  ARG*     3.0    12.2    +      -       -      +
    308B  GLU*     2.8    26.3    +      -       -      +
    419B  VAL*     4.1    16.8    -      -       +      -
    423B  VAL*     4.1     8.5    -      -       +      -
    567B  LEU*     3.5    46.0    -      -       +      +
    568B  VAL*     4.1    24.0    -      -       +      +
    571B  ASN*     3.9     4.2    +      -       +      +
    572B  THR*     6.1     0.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with TRP 305 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    201B  PHE*     4.7    16.0    -      +       -      -
    204B  HIS*     3.7    29.7    +      +       -      -
    232B  HIS*     5.9     1.0    -      +       -      -
    233B  ILE*     3.4    28.5    -      -       +      +
    301B  TYR*     2.9    25.0    +      +       +      +
    302B  ALA*     4.3     2.7    -      -       -      +
    304B  ILE*     1.3    77.5    -      -       +      +
    306B  LEU*     1.3    62.3    +      -       -      +
    308B  GLU*     3.4     5.0    +      -       +      +
    309B  HIS*     3.1    22.2    +      -       -      +
    336B  LEU*     3.6    37.7    -      -       +      +
    339B  GLU*     3.9    17.3    -      -       +      -
    340B  THR*     3.4    43.5    -      -       +      -
    343B  ILE*     4.3     6.5    -      -       +      -
    567B  LEU*     3.3    45.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 306 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    233B  ILE*     5.3     4.7    -      -       +      +
    252B  LEU*     4.3    24.2    -      -       +      -
    253B  LYS      3.4    24.9    -      -       -      +
    254B  TYR*     4.1    17.5    -      -       +      -
    261B  VAL*     4.9     4.7    -      -       +      -
    262B  TYR*     4.8     5.8    -      -       -      +
    263B  PRO*     4.1    23.8    -      -       +      -
    264B  PRO*     4.7     2.0    -      -       +      -
    302B  ALA      3.1    18.7    +      -       -      +
    303B  THR*     3.1     7.6    +      -       -      +
    305B  TRP*     1.3    72.5    -      -       -      +
    307B  ARG*     1.3    83.4    +      -       +      +
    308B  GLU      3.1     0.3    +      -       -      -
    309B  HIS*     3.1     7.0    +      -       -      +
    310B  ASN*     3.0    29.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 307 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    260B  GLU*     4.3    20.5    +      -       -      +
    261B  VAL*     2.7    66.6    +      -       +      +
    262B  TYR*     4.2     6.3    +      -       -      -
    303B  THR*     2.8    28.1    +      -       -      +
    304B  ILE*     3.3     9.5    -      -       -      +
    306B  LEU*     1.3    85.0    -      -       +      +
    308B  GLU*     1.3    63.0    +      -       -      +
    310B  ASN*     3.2     5.8    +      -       -      +
    311B  ARG*     3.0    21.1    +      -       -      +
    419B  VAL*     3.6    25.2    -      -       -      +
    420B  GLU*     4.6     1.2    +      -       -      -
    571B  ASN*     2.9    44.7    +      -       +      +
    572B  THR*     3.5    20.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 308 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    304B  ILE      2.8     9.8    +      -       -      +
    305B  TRP*     3.5    17.7    -      -       +      +
    307B  ARG*     1.3    72.6    -      -       -      +
    309B  HIS*     1.3    67.2    +      -       -      +
    311B  ARG*     2.6    51.9    +      -       -      +
    312B  VAL*     3.0    17.6    +      -       -      +
    336B  LEU*     4.0    10.8    -      -       +      -
    339B  GLU*     2.7    38.5    -      -       -      +
    567B  LEU*     4.1    14.8    -      -       +      -
    570B  LEU*     5.4     0.9    -      -       -      +
    571B  ASN*     3.1    25.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 309 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    233B  ILE*     5.5     0.4    -      -       +      -
    234B  TYR*     2.5    42.5    +      +       -      +
    250B  GLY      2.8    27.2    +      -       -      -
    252B  LEU*     3.5    25.3    +      -       +      +
    305B  TRP      3.1    10.7    +      -       -      +
    306B  LEU      3.1     6.3    +      -       -      +
    308B  GLU*     1.3    77.1    -      -       -      +
    310B  ASN*     1.3    79.8    +      -       -      +
    312B  VAL*     3.5     2.5    +      -       -      +
    313B  CYS*     3.1    22.6    +      -       -      -
    329B  PHE*     3.8    18.1    -      +       -      -
    332B  ALA*     3.6    24.1    -      -       +      +
    336B  LEU*     3.8    15.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 310 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    251B  LYS*     3.3    20.7    -      -       +      +
    252B  LEU*     2.7    35.9    +      -       -      +
    254B  TYR*     2.8    44.2    -      -       +      -
    261B  VAL*     5.5     0.4    -      -       -      +
    306B  LEU*     3.0    19.2    +      -       -      +
    307B  ARG*     3.6     9.6    -      -       -      +
    309B  HIS*     1.3    81.6    -      -       -      +
    311B  ARG*     1.3    64.2    +      -       -      +
    313B  CYS*     3.1    17.5    +      -       -      +
    314B  ASP*     3.3    11.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 311 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    307B  ARG      3.0    13.2    +      -       -      +
    308B  GLU*     2.6    50.1    +      -       -      +
    310B  ASN*     1.3    73.5    -      -       -      +
    312B  VAL*     1.3    71.9    +      -       -      +
    314B  ASP*     3.1    21.2    +      -       -      +
    315B  LEU*     3.3    30.6    +      -       +      +
    339B  GLU*     4.7     1.2    +      -       -      -
    558B  LEU*     4.6    11.9    -      -       -      +
    566B  LYS*     5.8     2.8    -      -       -      +
    570B  LEU*     3.4    40.7    -      -       -      +
    571B  ASN*     3.5    20.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 312 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    308B  GLU*     3.0    35.7    +      -       -      +
    309B  HIS      4.0     3.8    -      -       -      +
    311B  ARG*     1.3    77.2    -      -       -      +
    313B  CYS*     1.3    65.5    +      -       -      +
    315B  LEU*     2.9    20.2    +      -       +      +
    316B  LEU*     3.0    35.3    +      -       +      +
    332B  ALA*     4.6     5.8    -      -       +      -
    335B  ILE*     3.6    22.7    -      -       +      -
    336B  LEU*     4.0    15.9    -      -       +      -
    339B  GLU*     4.3     0.9    -      -       -      +
    558B  LEU*     3.6    23.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with CYS 313 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    249B  ASP*     3.2    17.5    -      -       -      +
    250B  GLY*     3.0    35.2    -      -       -      -
    251B  LYS*     4.0     9.2    -      -       +      -
    309B  HIS*     3.1    26.9    +      -       -      -
    310B  ASN      3.1     9.7    +      -       -      +
    312B  VAL*     1.3    75.1    -      -       -      +
    314B  ASP*     1.3    64.4    +      -       -      +
    316B  LEU*     3.2     9.0    +      -       -      +
    317B  LYS*     2.9    24.4    +      -       -      +
    328B  LEU*     3.9     7.6    -      -       -      +
    332B  ALA*     3.9    13.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with ASP 314 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    249B  ASP*     5.2     2.6    -      -       -      +
    251B  LYS*     3.2    34.7    +      -       -      -
    310B  ASN      3.3     5.3    +      -       -      +
    311B  ARG*     3.1    14.8    +      -       -      +
    313B  CYS*     1.3    80.0    -      -       -      +
    315B  LEU*     1.3    62.4    +      -       +      +
    317B  LYS*     3.4     7.7    +      -       -      +
    318B  ALA*     3.2    19.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 315 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    311B  ARG*     3.3    27.3    +      -       +      +
    312B  VAL*     2.9    22.6    +      -       -      +
    314B  ASP*     1.3    74.4    -      -       +      +
    316B  LEU*     1.3    72.0    +      -       +      +
    318B  ALA*     2.9    23.4    +      -       +      +
    319B  GLU*     3.3     8.8    +      -       -      +
    554B  VAL*     4.7    16.8    -      -       +      -
    558B  LEU*     3.8    28.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 316 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    312B  VAL*     3.0    46.8    +      -       +      +
    313B  CYS*     3.5     4.9    -      -       -      +
    315B  LEU*     1.3    83.8    -      -       +      +
    317B  LYS*     1.3    50.6    +      -       -      +
    319B  GLU*     3.2     5.3    +      -       +      -
    320B  HIS*     2.6    54.2    +      -       +      +
    323B  TRP*     4.1     4.7    -      -       +      -
    328B  LEU*     3.4    22.9    -      -       +      +
    331B  THR*     3.9    19.1    -      -       +      -
    332B  ALA*     4.7     6.3    -      -       +      +
    335B  ILE*     3.8    10.3    -      -       +      -
    550B  PHE      4.1    17.7    -      -       -      +
    551B  GLY*     4.6     2.5    -      -       -      +
    554B  VAL*     5.4     4.9    -      -       +      -
    555B  GLY*     5.1     7.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 317 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    249B  ASP*     3.7    28.4    +      -       +      +
    313B  CYS      2.9    15.5    +      -       -      +
    314B  ASP*     3.6    11.2    -      -       -      +
    315B  LEU      3.1     0.4    -      -       -      -
    316B  LEU*     1.3    73.2    -      -       -      +
    318B  ALA*     1.3    68.9    +      -       -      +
    320B  HIS      3.3     6.0    -      -       -      +
    321B  PRO*     3.2    39.8    +      -       +      +
    323B  TRP      2.9    27.5    +      -       -      -
    328B  LEU*     3.5    22.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 318 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    314B  ASP      3.2     9.9    +      -       -      +
    315B  LEU*     2.9    14.6    +      -       +      +
    317B  LYS*     1.3    79.1    -      -       -      +
    319B  GLU*     1.3    71.3    +      -       -      +
    321B  PRO*     3.7     8.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 319 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     50A  PHE*     4.1    20.7    -      -       +      +
     51A  GLY*     3.3    14.2    +      -       -      -
    315B  LEU      3.3     7.6    +      -       -      +
    316B  LEU*     3.2     9.3    +      -       +      +
    318B  ALA*     1.3    85.5    -      -       -      +
    320B  HIS*     1.3    83.4    +      -       +      +
    321B  PRO*     2.8    12.5    -      -       -      +
    551B  GLY      5.0     1.6    -      -       -      +
    554B  VAL*     3.8    33.6    -      -       +      +
----------------------------------------------------------
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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