Contacts of the helix formed by residues 327 - 352 (chain D) in PDB entry 4EC4


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 CYS 327 (chain D).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    252D  ASN      4.5     1.7    +      -       -      -
    300D  CYS*     3.9     3.1    -      -       -      -
    302D  HIS*     4.0     5.2    -      -       -      -
    303D  CYS*     3.3    28.0    -      -       +      +
    320D  HIS*     4.0     0.4    -      -       -      -
    324D  TYR      3.4    15.1    +      -       -      +
    325D  PRO      3.3     4.2    -      -       -      +
    326D  GLY*     1.3    74.9    -      -       -      +
    328D  LYS*     1.3    61.1    +      -       -      +
    329D  TYR*     3.2    10.7    +      -       -      -
    330D  LEU*     3.2    14.2    +      -       +      +
    331D  LEU*     2.9    26.9    +      -       -      +
    339D  ILE*     5.8     0.2    -      -       -      +
    401D   ZN      2.3    36.3    -      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 328 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    253D  SER*     4.3     7.8    -      -       -      +
    254D  THR*     3.2    36.4    +      -       -      +
    255D  ASN*     2.9    42.8    +      -       -      +
    302D  HIS*     3.8     9.9    +      -       +      -
    326D  GLY      3.3     6.3    +      -       -      +
    327D  CYS*     1.3    74.9    -      -       -      +
    329D  TYR*     1.3    56.7    +      -       -      +
    331D  LEU*     3.5    27.5    -      -       +      +
    332D  GLU*     3.1    29.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 329 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    263D  ALA      5.9     0.9    -      -       -      -
    268D  ARG*     3.6    14.6    +      -       -      -
    286D  ARG*     3.3    15.9    +      -       -      +
    287D  ALA      3.9     5.8    -      -       -      -
    288D  GLY*     3.6    27.8    -      -       -      -
    300D  CYS*     5.2     0.7    -      -       -      -
    301D  PHE*     3.5    31.9    -      +       -      -
    302D  HIS*     3.7    30.9    +      +       +      -
    317D  TRP*     4.5     2.0    -      +       -      -
    320D  HIS*     4.8     3.6    -      +       -      -
    327D  CYS*     3.2     3.8    -      -       -      -
    328D  LYS*     1.3    75.1    -      -       -      +
    330D  LEU*     1.3    70.2    +      -       -      +
    331D  LEU      3.1     1.3    -      -       -      -
    332D  GLU*     3.0    15.0    +      -       +      +
    333D  GLN*     2.8    66.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 330 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    317D  TRP*     3.7    39.0    -      -       +      +
    320D  HIS*     3.9    18.8    -      -       +      +
    321D  ALA*     3.6    37.0    -      -       +      +
    324D  TYR      3.9    12.1    -      -       -      +
    325D  PRO*     4.7     1.8    -      -       +      -
    327D  CYS*     3.2    16.9    +      -       +      +
    329D  TYR*     1.3    82.7    -      -       -      +
    331D  LEU*     1.3    58.1    +      -       -      +
    333D  GLN*     3.2     2.8    +      -       -      -
    334D  LYS*     2.8    46.8    +      -       +      +
    338D  TYR*     4.6     4.7    -      -       +      -
    339D  ILE*     4.1    16.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 331 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    325D  PRO      5.7     2.2    -      -       -      +
    326D  GLY      5.5     3.6    -      -       -      +
    327D  CYS      2.9    17.0    +      -       -      +
    328D  LYS*     3.5    37.2    -      -       +      +
    329D  TYR      3.1     0.2    -      -       -      -
    330D  LEU*     1.3    76.2    -      -       -      +
    332D  GLU*     1.3    56.4    +      -       -      +
    335D  GLY*     2.7    32.6    +      -       -      -
    336D  GLN*     3.8    50.9    -      -       +      +
    339D  ILE*     4.1    10.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 332 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    255D  ASN*     6.0     4.5    -      -       -      +
    328D  LYS*     3.1    15.9    +      -       +      +
    329D  TYR*     3.0    19.2    +      -       +      +
    331D  LEU*     1.3    80.9    -      -       +      +
    333D  GLN*     1.3    67.3    +      -       +      +
    334D  LYS      3.3     0.5    +      -       -      -
    335D  GLY*     4.1     2.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLN 333 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    286D  ARG*     4.8     2.9    -      -       -      +
    317D  TRP*     3.5    29.9    -      -       +      -
    329D  TYR*     2.8    65.2    +      -       +      +
    330D  LEU      3.9     0.9    -      -       -      +
    332D  GLU*     1.3    79.2    -      -       +      +
    334D  LYS*     1.3    70.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 334 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    337B  GLU*     5.3     3.6    -      -       -      +
    317D  TRP*     3.7    55.6    -      -       +      +
    330D  LEU*     2.8    18.4    +      -       +      +
    333D  GLN*     1.3    89.7    +      -       -      +
    335D  GLY*     1.3    66.4    +      -       -      +
    337D  GLU*     5.2     1.2    -      -       -      +
    338D  TYR*     3.3    55.6    +      -       +      +
    339D  ILE*     5.1     0.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 335 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    331D  LEU*     2.7    24.1    +      -       -      -
    332D  GLU      4.1     2.7    +      -       -      -
    333D  GLN      3.9     0.4    -      -       -      -
    334D  LYS*     1.3    76.9    -      -       -      +
    336D  GLN*     1.3    64.5    +      -       -      -
    337D  GLU*     3.2     4.8    +      -       -      -
    338D  TYR      3.7     2.3    +      -       -      -
    339D  ILE*     2.9    21.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 336 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    325D  PRO      4.9     8.1    +      -       -      -
    331D  LEU*     3.8    33.6    -      -       +      +
    335D  GLY*     1.3    71.5    -      -       -      -
    337D  GLU*     1.3    71.3    +      -       -      +
    339D  ILE*     3.6    12.0    -      -       -      +
    340D  ASN*     2.4    67.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 337 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    334B  LYS*     5.7     2.5    +      -       -      +
    337B  GLU*     3.6    24.7    -      -       +      +
    338B  TYR*     4.0    29.9    -      -       +      +
    341B  ASN*     3.2    33.3    +      -       +      +
    334D  LYS      5.2     0.9    -      -       -      +
    335D  GLY*     3.2     3.3    -      -       -      -
    336D  GLN*     1.3    82.6    +      -       -      +
    338D  TYR*     1.3    67.8    +      -       -      +
    340D  ASN*     3.0     5.5    +      -       -      +
    341D  ASN*     2.9    30.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 338 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    337B  GLU*     4.1    32.2    -      -       +      +
    315D  ASP*     3.4    10.4    +      -       -      -
    317D  TRP*     3.4    29.6    -      -       +      +
    318D  GLU*     3.1    27.5    +      -       -      +
    321D  ALA*     4.3     6.3    -      -       +      -
    330D  LEU*     4.6     3.8    -      -       +      -
    334D  LYS*     3.3    52.7    +      -       +      +
    335D  GLY      3.7     1.0    +      -       -      -
    336D  GLN      3.6     0.2    -      -       -      -
    337D  GLU*     1.3    78.3    -      -       -      +
    339D  ILE*     1.3    72.5    +      -       +      +
    341D  ASN*     3.2     2.9    +      -       -      +
    342D  ILE*     3.2    43.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 339 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    321D  ALA*     4.2    10.8    -      -       +      -
    325D  PRO*     3.7    38.6    -      -       +      +
    327D  CYS      5.8     0.2    -      -       -      +
    330D  LEU*     4.1    27.8    -      -       +      +
    331D  LEU*     4.1    23.6    -      -       +      +
    334D  LYS*     5.0     0.4    -      -       +      -
    335D  GLY      2.9    32.8    -      -       -      +
    336D  GLN*     3.6    15.5    -      -       -      +
    337D  GLU      3.4     0.4    -      -       -      -
    338D  TYR*     1.3    83.2    -      -       +      +
    340D  ASN*     1.3    71.4    +      -       -      +
    342D  ILE*     3.1    10.6    +      -       -      +
    343D  HIS*     3.3    22.8    +      -       +      -
    403D  P33      5.5     3.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 340 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    341B  ASN*     3.9    17.0    -      -       -      +
    336D  GLN*     2.4    47.2    +      -       -      +
    337D  GLU*     3.0     5.3    +      -       -      +
    339D  ILE*     1.3    80.4    -      -       -      +
    341D  ASN*     1.3    60.7    +      -       -      +
    343D  HIS*     3.3     6.6    +      -       -      +
    344D  LEU*     2.9    39.4    +      -       +      +
    403D  P33      3.4    27.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 341 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    337B  GLU*     2.7    49.7    +      -       -      +
    340B  ASN*     4.0     5.5    -      -       -      +
    341B  ASN*     2.9    37.9    -      -       -      +
    344B  LEU*     3.7    16.1    -      -       +      +
    337D  GLU      2.9    15.8    +      -       -      +
    338D  TYR      3.8     3.6    -      -       -      +
    340D  ASN*     1.3    76.1    -      -       -      +
    342D  ILE*     1.3    61.1    +      -       +      +
    344D  LEU*     3.8     3.7    -      -       -      +
    345D  THR*     2.6    36.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 342 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    318D  GLU*     3.8    39.7    -      -       +      +
    321D  ALA*     4.2     4.9    -      -       +      -
    322D  LYS*     4.1    27.4    -      -       +      +
    338D  TYR*     3.2    40.9    +      -       +      +
    339D  ILE      3.1     9.7    +      -       -      +
    341D  ASN*     1.3    77.8    -      -       +      +
    343D  HIS*     1.3    60.0    +      -       +      +
    345D  THR*     4.4     4.1    -      -       -      +
    346D  HIS*     3.0    32.7    +      -       +      -
----------------------------------------------------------
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Residues in contact with HIS 343 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    321D  ALA      2.7    28.6    +      -       -      -
    322D  LYS*     3.4    20.6    -      -       -      -
    325D  PRO*     3.4    17.3    -      -       +      +
    339D  ILE*     3.3    27.7    +      -       +      +
    340D  ASN*     3.3     7.0    +      -       -      +
    341D  ASN      3.1     0.4    -      -       -      -
    342D  ILE*     1.3    78.8    -      -       +      +
    344D  LEU*     1.3    60.5    +      -       -      +
    345D  THR      3.2     1.3    -      -       -      -
    346D  HIS*     3.1     7.9    +      -       -      +
    347D  SER*     2.6    34.7    +      -       -      +
    403D  P33      4.0    41.1    +      -       -      +
    250K  PHE*     3.8    22.3    -      +       -      -
    253K  SER*     5.8     3.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 344 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    341B  ASN*     3.8    26.7    -      -       -      +
    344B  LEU*     4.2    19.5    -      -       +      +
    345B  THR*     4.1    24.5    -      -       -      +
    348B  LEU*     4.1    27.8    -      -       +      +
    340D  ASN*     2.9    28.8    +      -       +      +
    341D  ASN*     3.8    11.4    -      -       -      +
    343D  HIS*     1.3    75.4    -      -       -      +
    345D  THR*     1.3    57.8    +      -       -      +
    347D  SER*     3.3     6.4    +      -       -      -
    348D  LEU*     2.9    30.0    +      -       -      +
    403D  P33      4.9    10.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 345 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    344B  LEU*     3.8    26.3    -      -       +      +
    341D  ASN      2.6    25.3    +      -       -      -
    342D  ILE*     4.4     5.6    -      -       -      +
    344D  LEU*     1.3    77.2    -      -       -      +
    346D  HIS*     1.3    62.3    +      -       -      +
    348D  LEU*     3.4     9.4    +      -       +      +
    349D  GLU*     3.1    22.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 346 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    318D  GLU*     4.5    13.1    +      -       -      -
    322D  LYS*     3.5    44.2    +      -       +      +
    342D  ILE*     3.0    25.5    +      -       +      +
    343D  HIS*     3.1     9.8    +      -       -      +
    345D  THR*     1.3    80.1    -      -       -      +
    347D  SER*     1.3    54.4    +      -       -      +
    349D  GLU*     2.9    41.8    +      -       -      +
    350D  GLU*     2.8    23.5    +      -       -      +
    248K  ARG*     3.9    10.5    +      -       -      -
    250K  PHE*     3.6    23.8    -      +       +      -
----------------------------------------------------------
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Residues in contact with SER 347 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    348B  LEU*     4.0    13.8    -      -       -      +
    343D  HIS*     2.6    25.6    +      -       -      +
    344D  LEU*     3.7     6.9    -      -       -      -
    346D  HIS*     1.3    75.0    -      -       -      +
    348D  LEU*     1.3    65.6    +      -       -      +
    350D  GLU*     3.4     7.3    +      -       -      -
    351D  CYS*     3.3    12.1    +      -       -      +
    250K  PHE*     5.6     3.0    -      -       -      -
    253K  SER*     3.2    26.4    +      -       -      +
    254K  THR*     3.2    32.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 348 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    344B  LEU*     4.5    18.4    -      -       +      +
    347B  SER*     3.6    32.5    -      -       -      +
    348B  LEU*     3.7    19.4    -      -       +      +
    351B  CYS*     4.7     3.6    -      -       +      -
    344D  LEU      2.9    15.3    +      -       -      +
    345D  THR*     3.5     9.9    -      -       +      +
    347D  SER*     1.3    76.5    -      -       -      +
    349D  GLU*     1.3    63.6    +      -       -      +
    351D  CYS*     3.0    20.9    +      -       -      +
    352D  LEU*     3.4    28.3    -      -       +      +
    253G  SER      5.9     1.6    -      -       -      +
    254G  THR*     4.6    13.5    -      -       -      +
    255G  ASN      6.0     0.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 349 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    345D  THR      3.1     7.8    +      -       -      +
    346D  HIS*     2.9    50.6    +      -       -      +
    348D  LEU*     1.3    80.1    -      -       -      +
    350D  GLU*     1.3    61.9    +      -       -      +
    352D  LEU*     3.1    28.4    +      -       -      +
    248K  ARG*     3.8    18.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 350 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    346D  HIS      2.8    23.0    +      -       -      +
    347D  SER*     3.6    12.3    -      -       -      +
    348D  LEU      3.2     0.4    -      -       -      -
    349D  GLU*     1.3    78.8    -      -       -      +
    351D  CYS*     1.3    62.1    +      -       -      +
    352D  LEU      3.2     5.2    +      -       -      +
    353D  VAL      4.4     0.3    -      -       -      +
    246K  SER*     5.9     1.1    -      -       -      +
    248K  ARG*     2.6    28.4    +      -       -      +
    250K  PHE*     4.5     2.9    -      -       -      -
    251K  PRO      3.1    12.4    -      -       -      +
    252K  ASN*     2.9    26.8    -      -       -      +
    253K  SER      5.3     1.1    +      -       -      -
    254K  THR*     4.3     6.3    -      -       +      +
    256K  LEU*     4.1    19.7    -      -       +      +
    258K  ARG*     2.5    41.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with CYS 351 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    348B  LEU*     5.2     3.4    -      -       -      -
    351B  CYS*     3.3    44.6    -      -       +      -
    352B  LEU*     4.7    15.5    -      -       -      -
    347D  SER      3.3    10.0    +      -       -      +
    348D  LEU*     3.0    15.8    +      -       -      +
    350D  GLU*     1.3    79.8    -      -       -      +
    352D  LEU*     1.3    57.2    +      -       -      +
    353D  VAL*     3.1    19.4    -      -       -      +
    254K  THR*     4.7    13.0    -      -       -      +
    255K  ASN      6.0     0.4    -      -       -      -
    256K  LEU*     5.8     7.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 352 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    351B  CYS*     3.0    35.7    -      -       -      -
    348D  LEU*     3.4    28.0    -      -       +      +
    349D  GLU*     3.1    18.2    +      -       -      +
    350D  GLU      3.1     4.3    -      -       -      +
    351D  CYS*     1.3    78.1    -      -       -      +
    353D  VAL*     1.3    56.9    +      -       +      +
    254G  THR*     5.4     0.2    -      -       -      +
    255G  ASN*     3.6    37.5    -      -       +      +
    256G  LEU*     4.0    11.7    -      -       +      -
----------------------------------------------------------
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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
------------------------------------------------------------
  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