Contacts of the helix formed by residues 315 - 338 (chain B) in PDB entry 3A3K


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

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

Legend:
Dist - nearest distance (Å) between atoms of two residues
Surf - contact surface area (Å2) between two residues
HB   - hydrophilic-hydrophilic contact (hydrogen bond)
Arom - aromatic-aromatic contact
Phob - hydrophobic-hydrophobic contact
DC   - hydrophobic-hydrophilic contact (destabilizing contact)
+/-  - indicates presence/absence of a specific contacts
*    - indicates residues forming contacts  by their side chain
       (including CA atoms)
Residues in contact with ASN 315 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     22B  ARG*     4.3    13.0    +      -       -      -
    290B  TYR*     3.5    13.3    +      -       -      +
    293B  PHE*     4.6     2.6    -      -       -      -
    294B  LEU*     3.8    22.5    -      -       +      +
    297B  LEU*     4.2     6.0    -      -       +      +
    298B  LYS*     5.5     1.4    -      -       -      +
    309B  VAL*     3.4    24.0    -      -       -      +
    310B  GLU      2.8    25.6    +      -       -      +
    311B  ASP*     3.8     5.1    +      -       -      +
    312B  GLY*     3.2    24.5    +      -       -      +
    313B  LEU      2.9     1.2    +      -       -      -
    314B  LYS*     1.3    75.2    -      -       -      +
    316B  ILE*     1.3    61.9    +      -       -      +
    317B  ILE      3.1     0.4    -      -       -      -
    318B  PRO*     3.3    18.1    -      -       +      +
    319B  ALA*     3.3    12.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 316 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    128B  PRO*     4.1    14.4    -      -       +      -
    244B  PHE*     4.8     0.7    -      -       +      -
    282B  TYR*     3.9    40.2    -      -       +      -
    283B  LYS      4.7     4.3    -      -       -      +
    284B  GLU*     5.7     0.2    -      -       -      +
    285B  PRO*     3.7    29.2    -      -       +      -
    290B  TYR*     3.4    15.5    +      -       -      +
    313B  LEU*     3.0    25.9    +      -       +      +
    315B  ASN*     1.3    77.1    -      -       -      +
    317B  ILE*     1.3    64.4    +      -       +      +
    319B  ALA*     3.6     6.7    -      -       -      +
    320B  SER*     2.5    46.0    +      -       -      +
    361B  THR*     5.0     3.4    -      -       +      -
    374B  THR*     6.0     0.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 317 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     17B  PRO*     3.5    31.4    -      -       +      +
     18B  TRP*     4.0    20.9    -      -       +      -
    107B  ALA*     3.5    25.9    -      -       -      +
    108B  GLY*     5.3     1.8    -      -       -      -
    128B  PRO*     3.8    23.1    -      -       +      -
    244B  PHE*     4.0    28.9    -      -       +      -
    314B  LYS      3.4    10.3    -      -       -      +
    316B  ILE*     1.3    76.7    -      -       +      +
    318B  PRO*     1.4    67.7    -      -       +      +
    320B  SER*     3.1     3.4    +      -       -      -
    321B  PHE*     3.0    40.7    +      -       +      -
----------------------------------------------------------
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Residues in contact with PRO 318 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     17B  PRO      3.5     9.9    -      -       -      +
     22B  ARG*     3.7    43.3    -      -       +      +
     23B  VAL*     4.2    12.3    -      -       +      -
     26B  ALA*     3.4    19.0    -      -       +      +
    293B  PHE*     4.3     0.2    -      -       -      -
    297B  LEU*     4.4    14.1    -      -       +      -
    314B  LYS      3.3    10.8    -      -       -      +
    315B  ASN*     3.3    19.3    -      -       -      +
    317B  ILE*     1.4    94.5    -      -       +      +
    319B  ALA*     1.3    55.1    +      -       -      +
    321B  PHE*     3.2     2.6    +      -       +      +
    322B  HIS      2.9    24.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 319 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    290B  TYR*     3.9    12.3    -      -       +      -
    293B  PHE*     3.5    26.5    -      -       +      -
    315B  ASN      3.3    16.9    +      -       -      +
    316B  ILE      3.6     2.5    -      -       -      +
    317B  ILE      3.2     0.8    -      -       -      -
    318B  PRO*     1.3    78.6    -      -       -      +
    320B  SER*     1.3    57.6    +      -       -      +
    322B  HIS*     3.2     3.8    -      -       -      +
    323B  ASP*     2.9    31.2    +      -       -      +
    360B  VAL*     3.9     4.7    -      -       +      +
    361B  THR*     3.6    22.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 320 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    107B  ALA*     3.7    14.4    -      -       -      -
    126B  THR*     2.9    36.6    +      -       -      -
    127B  GLY*     4.1     5.2    -      -       -      -
    128B  PRO*     5.1     1.4    -      -       -      +
    316B  ILE*     2.5    31.9    +      -       -      +
    317B  ILE*     3.1     1.1    +      -       -      -
    319B  ALA*     1.3    71.2    -      -       -      +
    321B  PHE*     1.3    60.7    +      -       -      +
    323B  ASP*     4.1     7.1    -      -       -      +
    324B  GLY      2.8    21.8    +      -       -      -
    361B  THR*     4.0     4.4    -      -       -      +
    372B  ARG*     3.1    17.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 321 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      9B  LEU*     4.0    22.4    -      -       +      -
     18B  TRP*     3.8    23.8    -      -       +      -
     23B  VAL*     3.6    32.8    -      -       +      -
     27B  VAL*     4.9     5.6    -      -       +      -
     82B  LEU*     3.9    25.8    -      -       +      +
     83B  GLY*     3.9    16.2    -      -       -      -
     85B  GLY*     5.2     0.2    -      -       -      -
    105B  LEU*     5.3     0.4    -      -       +      -
    106B  THR*     3.8    19.3    -      -       -      -
    107B  ALA*     3.5    33.2    -      -       +      +
    108B  GLY      4.4     1.6    -      -       -      -
    126B  THR*     4.6     1.8    -      -       -      -
    317B  ILE*     3.0    26.8    +      -       +      -
    318B  PRO      3.2     7.6    +      -       -      +
    320B  SER*     1.3    74.5    -      -       -      +
    322B  HIS*     1.3    60.0    +      -       -      +
    324B  GLY*     3.7     0.6    -      -       -      -
    325B  LEU*     2.9    31.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 322 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     26B  ALA*     3.3    30.4    -      -       -      +
     27B  VAL*     5.3     1.1    -      -       -      +
     29B  LEU*     4.1     7.8    +      -       +      +
     30B  ALA*     3.7    23.2    +      -       +      +
     33B  ARG*     3.7    21.0    +      -       -      -
    293B  PHE*     3.5    27.8    -      +       +      -
    318B  PRO      2.9    12.8    +      -       -      +
    319B  ALA      3.2    10.5    -      -       -      +
    321B  PHE*     1.3    76.2    -      -       -      +
    323B  ASP*     1.3    82.6    +      -       -      +
    325B  LEU*     3.4     3.2    +      -       -      +
    326B  LEU*     3.2    48.6    +      -       +      +
    360B  VAL*     3.8     8.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASP 323 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    126B  THR*     6.1     0.4    -      -       -      -
    319B  ALA      2.9    19.0    +      -       -      +
    320B  SER*     4.1     6.5    -      -       -      +
    321B  PHE      3.3     0.2    -      -       -      -
    322B  HIS*     1.3    91.3    +      -       -      +
    324B  GLY*     1.3    56.8    +      -       -      +
    326B  LEU*     3.4     7.1    +      -       -      +
    327B  LEU*     2.9    30.2    +      -       -      +
    357B  PHE*     3.9     5.2    -      -       +      -
    359B  GLY*     3.5    11.3    -      -       -      -
    360B  VAL*     3.0    21.3    +      -       -      +
    361B  THR*     2.9    40.5    +      -       -      +
    364B  LEU*     3.9    20.4    -      -       +      +
    372B  ARG*     5.3     0.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 324 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    105B  LEU*     3.7    10.3    -      -       -      +
    126B  THR*     3.6    28.3    -      -       -      +
    320B  SER      2.8    23.0    +      -       -      -
    321B  PHE*     3.7     1.1    -      -       -      -
    323B  ASP*     1.3    70.7    -      -       -      +
    325B  LEU*     1.3    58.5    +      -       -      +
    327B  LEU*     3.3     6.2    +      -       -      +
    328B  TYR*     2.9    29.6    +      -       -      +
    352B  MET*     5.1     0.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 325 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      5B  VAL*     4.7    18.4    -      -       +      -
     27B  VAL*     3.7    35.7    -      -       +      -
     30B  ALA*     4.1    18.2    -      -       +      -
     31B  LEU*     4.1    17.5    -      -       +      -
     46B  VAL*     5.6     0.9    -      -       +      -
     48B  MET*     5.3     2.9    -      -       -      -
     80B  VAL*     5.7     0.9    -      -       +      -
     82B  LEU*     4.5    17.5    -      -       +      -
    105B  LEU*     4.1     8.2    -      -       +      +
    321B  PHE      2.9    17.0    +      -       -      +
    322B  HIS      3.7     5.2    -      -       -      +
    324B  GLY*     1.3    75.6    -      -       -      +
    326B  LEU*     1.3    58.2    +      -       +      +
    328B  TYR*     3.3    19.2    +      -       +      +
    329B  VAL*     2.8    39.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 326 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30B  ALA*     3.9    15.7    -      -       +      +
     33B  ARG*     3.9    31.4    -      -       +      +
     34B  VAL*     3.7    29.2    -      -       +      -
     40B  LEU*     5.2     6.9    -      -       +      +
    322B  HIS*     3.2    40.4    +      -       +      +
    323B  ASP*     3.7     9.6    -      -       -      +
    325B  LEU*     1.3    75.3    -      -       +      +
    327B  LEU*     1.3    60.9    +      -       -      +
    329B  VAL*     3.2     7.7    +      -       +      +
    330B  GLN*     2.9    30.3    +      -       -      +
    357B  PHE*     4.0    19.5    -      -       +      -
    358B  GLN      6.1     0.2    -      -       -      +
    359B  GLY*     5.9     2.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 327 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    124B  THR*     5.0     1.1    -      -       +      -
    126B  THR*     4.6    12.1    -      -       +      -
    323B  ASP      2.9    19.3    +      -       -      +
    324B  GLY      3.5     4.3    -      -       -      +
    326B  LEU*     1.3    76.5    -      -       -      +
    328B  TYR*     1.3    60.8    +      -       -      +
    330B  GLN*     3.3     4.2    +      -       -      +
    331B  ALA*     3.1    20.5    +      -       +      +
    352B  MET*     4.0    30.1    -      -       +      +
    355B  ARG*     4.2    20.6    +      -       +      +
    356B  SER      5.2     0.2    -      -       -      +
    357B  PHE*     3.8    41.8    -      -       +      -
    364B  LEU*     4.7     6.5    -      -       +      -
    366B  ILE*     3.8    33.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 328 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      3B  LEU*     3.6    30.3    -      -       +      +
      5B  VAL*     5.3     0.7    -      -       +      -
     46B  VAL*     6.5     0.2    -      -       +      -
     79B  ALA*     3.9    11.3    +      -       -      +
     80B  VAL*     3.6    35.2    -      -       +      +
    103B  PRO*     4.7     7.9    -      -       +      -
    105B  LEU*     3.5    28.3    -      -       +      -
    324B  GLY      2.9    13.6    +      -       -      +
    325B  LEU*     3.5    21.5    -      -       +      +
    326B  LEU      3.2     0.2    -      -       -      -
    327B  LEU*     1.3    73.2    -      -       -      +
    329B  VAL*     1.3    74.8    +      -       +      +
    331B  ALA*     2.9    13.2    +      -       -      +
    332B  VAL*     2.9    41.8    +      -       +      +
    342B  VAL      4.3     4.9    +      -       -      -
    348B  ILE*     3.9    20.2    -      -       +      -
    352B  MET*     3.7    16.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 329 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31B  LEU*     5.8     0.4    -      -       +      -
     34B  VAL*     4.0    21.3    -      -       +      -
     40B  LEU*     4.0    31.0    -      -       +      -
     41B  LEU*     3.6    38.4    -      -       +      +
     46B  VAL*     4.8     7.6    -      -       +      -
    325B  LEU*     2.8    29.5    +      -       +      +
    326B  LEU*     3.2    11.6    +      -       +      +
    328B  TYR*     1.3    80.8    -      -       +      +
    330B  GLN*     1.3    61.6    +      -       -      +
    332B  VAL*     3.5     0.8    +      -       -      -
    333B  THR*     2.9    28.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLN 330 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     37B  ARG*     4.4     7.7    +      -       -      +
     40B  LEU*     3.6    29.2    -      -       -      +
    326B  LEU      2.9    14.3    +      -       -      +
    327B  LEU      3.6     8.7    -      -       -      +
    329B  VAL*     1.3    77.2    -      -       -      +
    331B  ALA*     1.3    60.9    +      -       -      +
    333B  THR*     3.6    11.3    +      -       -      +
    334B  GLU*     3.3    35.6    +      -       -      +
    355B  ARG*     3.1    29.6    -      -       -      +
    357B  PHE*     4.2    18.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 331 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    327B  LEU      3.1    11.8    +      -       -      +
    328B  TYR      2.9     9.9    +      -       -      +
    330B  GLN*     1.3    75.2    -      -       -      +
    332B  VAL*     1.3    59.5    +      -       -      +
    334B  GLU*     3.4    10.2    +      -       -      -
    335B  THR*     3.0    31.1    +      -       -      -
    348B  ILE*     3.6    28.7    -      -       +      +
    351B  ARG*     3.7    14.4    -      -       +      +
    352B  MET*     3.7    14.6    -      -       +      -
    355B  ARG*     5.2     2.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 332 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      3B  LEU*     4.1     3.4    -      -       +      -
     41B  LEU*     3.7    20.0    -      -       +      -
    328B  TYR*     2.9    53.3    +      -       +      +
    329B  VAL*     4.6     0.9    -      -       -      -
    331B  ALA*     1.3    74.1    -      -       -      +
    333B  THR*     1.3    59.5    +      -       -      +
    335B  THR*     3.0     8.7    +      -       -      -
    336B  LEU*     2.8    31.8    +      -       +      +
    341B  THR      5.4     0.2    -      -       -      -
    342B  VAL*     3.7    38.4    -      -       +      -
    348B  ILE*     4.0    12.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 333 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39B  ASP      3.5    23.8    -      -       -      +
     40B  LEU*     3.6    13.1    -      -       +      +
     41B  LEU*     3.0    26.2    +      -       -      +
     42B  PRO*     4.5     6.5    -      -       +      -
    329B  VAL      2.9    20.0    +      -       -      -
    330B  GLN*     3.7    13.2    -      -       -      +
    331B  ALA      3.3     0.2    -      -       -      -
    332B  VAL*     1.3    76.5    -      -       -      +
    334B  GLU*     1.3    58.9    +      -       +      +
    336B  LEU*     3.2     8.9    +      -       -      +
    337B  ALA*     2.9    30.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 334 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    330B  GLN*     3.3    26.9    +      -       -      +
    331B  ALA*     3.7     7.0    -      -       -      +
    333B  THR*     1.3    79.1    -      -       +      +
    335B  THR*     1.3    61.2    +      -       -      +
    337B  ALA*     3.5     7.3    +      -       -      +
    338B  GLN*     3.3    37.0    +      -       -      +
    351B  ARG*     3.7    24.6    +      -       -      +
    355B  ARG*     2.7    40.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with THR 335 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    331B  ALA      3.0    15.1    +      -       -      -
    332B  VAL*     3.0     9.6    +      -       -      -
    334B  GLU*     1.3    75.6    -      -       -      +
    336B  LEU*     1.3    63.3    +      -       -      +
    338B  GLN*     3.2     8.7    +      -       -      +
    340B  GLY*     3.0    34.7    +      -       -      -
    341B  THR      3.7    23.8    -      -       -      +
    344B  ASP*     4.3     7.9    -      -       +      +
    347B  ASN*     4.7     4.0    -      -       +      -
    348B  ILE*     3.6    22.2    -      -       +      +
    351B  ARG*     3.2    29.1    +      -       -      +
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Residues in contact with LEU 336 (chain B). Click here for Legend to table.
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                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
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     41B  LEU*     4.5     7.4    -      -       +      -
     42B  PRO*     4.3    21.8    -      -       +      +
     44B  TRP*     3.6    44.2    -      -       +      +
    332B  VAL*     2.8    34.0    +      -       +      +
    333B  THR*     3.6     5.6    -      -       -      +
    335B  THR*     1.3    71.6    -      -       -      +
    337B  ALA*     1.3    63.5    +      -       -      +
    339B  GLY*     3.0    15.2    +      -       -      -
    340B  GLY      3.8    17.7    -      -       -      +
    341B  THR*     4.3    11.4    -      -       -      +
    342B  VAL*     4.4     4.5    -      -       +      +
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Residues in contact with ALA 337 (chain B). Click here for Legend to table.
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                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
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    333B  THR*     2.9    18.7    +      -       +      +
    334B  GLU*     3.5    11.4    -      -       -      +
    335B  THR      3.3     0.4    -      -       -      -
    336B  LEU*     1.3    76.3    -      -       -      +
    338B  GLN*     1.3    64.5    +      -       +      +
    339B  GLY      3.5     0.6    +      -       -      -
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Residues in contact with GLN 338 (chain B). Click here for Legend to table.
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                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    334B  GLU*     3.3    26.7    +      -       -      +
    335B  THR      3.2     4.9    +      -       -      +
    336B  LEU      3.0     1.4    -      -       -      -
    337B  ALA*     1.3    84.3    -      -       +      +
    339B  GLY*     1.3    58.5    +      -       -      +
    340B  GLY      3.4     3.0    +      -       -      -
    351B  ARG*     2.9    31.7    +      -       -      +
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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
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  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) +   -    +    +   +   +    +    -
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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