Contacts of the helix formed by residues 26 - 54 (chain D) in PDB entry 3PJV


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

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

Legend:
Dist - nearest distance (Å) between atoms of two residues
Surf - contact surface area (Å2) between two residues
HB   - hydrophilic-hydrophilic contact (hydrogen bond)
Arom - aromatic-aromatic contact
Phob - hydrophobic-hydrophobic contact
DC   - hydrophobic-hydrophilic contact (destabilizing contact)
+/-  - indicates presence/absence of a specific contacts
*    - indicates residues forming contacts  by their side chain
       (including CA atoms)
Residues in contact with SER 26 (chain D).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     23D  PHE*     3.3    23.7    +      -       -      +
     24D  MSE      3.2     0.2    -      -       -      -
     25D  VAL*     1.3    79.7    -      -       -      +
     27D  LEU*     1.3    65.5    +      -       -      +
     28D  GLU      3.4     2.0    -      -       -      -
     29D  SER*     3.2    14.2    +      -       -      -
     30D  SER*     2.9    31.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 27 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     23D  PHE      3.1    15.6    +      -       -      +
     24D  MSE      3.3    44.3    +      -       +      +
     25D  VAL      3.4     0.4    -      -       -      -
     26D  SER*     1.3    77.4    -      -       -      +
     28D  GLU*     1.3    60.8    +      -       -      +
     30D  SER*     3.6     3.7    -      -       -      -
     31D  ARG*     2.8    39.5    +      -       +      +
    106F  PHE*     6.2     0.9    -      -       +      -
    109F  LEU      6.2     0.2    -      -       -      +
    110F  ILE*     4.0    27.8    -      -       +      -
    144F  LEU*     4.9    11.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 28 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24D  MSE      4.9     0.8    +      -       -      -
     25D  VAL      5.0     1.8    +      -       -      +
     26D  SER      3.4     0.6    -      -       -      -
     27D  LEU*     1.3    79.0    -      -       -      +
     29D  SER*     1.3    63.8    +      -       -      +
     31D  ARG*     3.5     9.4    +      -       +      +
     32D  THR*     3.1    30.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 29 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     26D  SER*     3.2    19.7    +      -       -      -
     28D  GLU*     1.3    74.5    -      -       -      +
     30D  SER*     1.3    68.6    +      -       -      +
     32D  THR*     3.3     8.3    +      -       -      -
     33D  GLN*     3.0    32.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 30 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     26D  SER*     2.9    30.3    +      -       -      -
     27D  LEU*     3.6     6.1    -      -       -      -
     29D  SER*     1.3    77.4    +      -       -      +
     31D  ARG*     1.3    62.8    +      -       -      +
     33D  GLN*     3.2    19.3    +      -       -      +
     34D  TYR*     3.1    32.6    +      -       -      -
    144F  LEU*     4.7    13.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 31 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27D  LEU*     2.8    27.6    +      -       +      +
     28D  GLU*     3.7     9.2    -      -       -      +
     30D  SER*     1.3    75.9    -      -       -      +
     32D  THR*     1.3    69.3    +      -       -      +
     34D  TYR*     3.1     9.8    +      -       -      +
     35D  VAL*     2.9    40.3    +      -       -      +
    110F  ILE*     2.8    39.8    +      -       +      +
    111F  GLY      2.9    29.7    +      -       -      -
    112F  LEU*     3.8    15.9    -      -       +      +
    113F  GLU*     4.6     4.9    -      -       -      +
    144F  LEU*     4.9     6.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with THR 32 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     28D  GLU*     3.1    17.4    +      -       -      +
     29D  SER*     3.6    11.2    -      -       -      -
     30D  SER      3.3     0.2    -      -       -      -
     31D  ARG*     1.3    83.7    +      -       -      +
     33D  GLN*     1.3    55.5    +      -       +      +
     35D  VAL*     3.2     9.0    +      -       +      +
     36D  ASN*     2.8    48.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 33 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     29D  SER*     3.0    27.0    +      -       -      +
     30D  SER*     3.2    21.2    +      -       -      +
     32D  THR*     1.3    76.8    -      -       +      +
     34D  TYR*     1.3    63.5    +      -       +      +
     36D  ASN*     3.4     8.1    +      -       -      +
     37D  GLN*     2.9    30.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 34 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30D  SER*     3.1    26.1    +      -       -      -
     31D  ARG*     3.1     7.0    +      -       -      +
     33D  GLN*     1.3    81.2    -      -       +      +
     35D  VAL*     1.3    62.1    +      -       -      +
     37D  GLN*     3.7    25.6    -      -       -      +
     38D  LEU*     2.9    36.7    +      -       -      +
    112F  LEU*     5.5     5.2    -      -       +      -
    140F  ALA*     4.0    25.1    -      -       +      -
    143F  LYS*     3.5    54.1    +      -       +      +
    144F  LEU*     3.5    40.8    -      -       +      -
    147F  SER*     4.5     6.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 35 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31D  ARG*     2.9    37.3    +      -       -      +
     32D  THR*     3.5    11.0    -      -       +      +
     34D  TYR*     1.3    76.0    -      -       -      +
     36D  ASN*     1.3    68.0    +      -       -      +
     38D  LEU*     4.0     5.6    -      -       -      +
     39D  ARG*     3.0    46.3    +      -       +      +
    112F  LEU*     3.7    25.8    -      -       +      -
    113F  GLU      5.9     2.0    -      -       -      +
    115F  ALA*     5.1     1.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 36 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     32D  THR*     2.8    38.4    +      -       -      +
     33D  GLN*     3.8     6.7    -      -       -      +
     35D  VAL*     1.3    77.9    -      -       -      +
     37D  GLN*     1.3    58.2    +      -       -      +
     39D  ARG*     3.0    30.4    +      -       -      +
     40D  SER*     2.9    35.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 37 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     33D  GLN      2.9    17.6    +      -       -      +
     34D  TYR*     3.7    33.0    +      -       -      +
     36D  ASN*     1.3    77.1    -      -       -      +
     38D  LEU*     1.3    59.3    +      -       +      +
     40D  SER*     3.3     6.8    +      -       -      -
     41D  HIS*     2.9    28.1    +      -       +      +
     72F  ASP      3.0    25.7    +      -       -      +
     73F  SER*     3.8    13.6    -      -       -      +
     75F  TYR*     6.5     1.1    -      -       -      -
    140F  ALA*     5.8     1.4    -      -       -      +
    143F  LYS*     4.8     5.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 38 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     34D  TYR      2.9    21.2    +      -       -      +
     35D  VAL*     4.0     4.3    -      -       -      +
     37D  GLN*     1.3    75.5    -      -       +      +
     39D  ARG*     1.3    63.3    +      -       -      +
     41D  HIS*     3.1     6.7    +      -       +      +
     42D  ALA*     3.0    23.2    +      -       -      +
     75F  TYR*     3.9    21.5    -      -       +      +
    112F  LEU*     4.2    12.6    -      -       +      -
    113F  GLU      5.9     1.6    -      -       -      +
    115F  ALA*     3.6    20.4    -      -       +      +
    135F  SER*     3.9    13.6    +      -       -      +
    136F  HIS      3.9    14.4    -      -       -      +
    137F  PRO*     3.9    27.4    -      -       +      -
    140F  ALA*     3.9    24.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 39 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     35D  VAL*     3.0    37.4    +      -       +      +
     36D  ASN*     3.0    30.9    +      -       -      +
     38D  LEU*     1.3    77.1    -      -       -      +
     40D  SER*     1.3    58.1    +      -       -      +
     42D  ALA*     3.2     5.0    +      -       -      +
     43D  GLN*     2.9    29.5    +      -       +      +
    115F  ALA*     3.9    12.7    -      -       +      +
    116F  GLY      3.8    20.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with SER 40 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     36D  ASN*     2.9    19.8    +      -       -      +
     37D  GLN*     3.6     6.5    -      -       -      -
     39D  ARG*     1.3    77.3    -      -       -      +
     41D  HIS*     1.3    57.6    +      -       -      +
     43D  GLN*     4.4     5.6    -      -       -      -
     44D  ASP*     2.9    45.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 41 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     37D  GLN*     2.9    15.9    +      -       +      +
     38D  LEU*     3.1    13.7    +      -       +      +
     40D  SER*     1.3    78.3    -      -       -      +
     42D  ALA*     1.3    61.3    +      -       -      +
     44D  ASP*     3.5     6.0    +      -       -      +
     45D  ALA*     3.2    21.5    +      -       -      +
     75D  TYR*     4.0    18.6    -      -       +      +
     76D  TYR*     3.3    35.7    +      +       -      -
     73F  SER      5.3     8.5    -      -       -      -
     74F  GLY*     6.5     0.2    -      -       -      -
     75F  TYR*     3.9    33.3    -      +       -      +
    135F  SER*     2.8    24.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 42 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     38D  LEU      3.0     8.3    +      -       -      +
     39D  ARG      3.7     5.8    -      -       -      +
     41D  HIS*     1.3    75.6    -      -       -      +
     43D  GLN*     1.3    64.6    +      -       -      +
     45D  ALA*     3.3     4.0    +      -       -      +
     46D  ALA*     3.0    22.7    +      -       -      +
    115F  ALA      3.5    23.1    -      -       -      +
    116F  GLY      3.8     0.9    -      -       -      -
    117F  GLY*     3.7    16.8    -      -       -      +
    133F  VAL*     3.7    16.7    -      -       +      +
    135F  SER*     3.2    19.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 43 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39D  ARG*     2.9    20.0    +      -       +      +
     40D  SER*     3.9     7.0    -      -       -      +
     42D  ALA*     1.3    75.6    -      -       -      +
     44D  ASP*     1.3    62.3    +      -       -      +
     46D  ALA      3.2     0.5    +      -       -      -
     47D  THR*     2.9    53.3    +      -       -      +
    116F  GLY      5.3     0.4    -      -       -      +
    117F  GLY*     3.7    10.7    -      -       -      -
    118F  ASP*     3.0    41.3    +      -       -      +
    119F  ALA*     4.4     0.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 44 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     40D  SER*     2.9    32.2    +      -       -      +
     41D  HIS*     3.9     6.0    -      -       -      +
     43D  GLN*     1.3    80.6    -      -       -      +
     45D  ALA*     1.3    57.1    +      -       -      +
     47D  THR*     3.4     5.8    +      -       -      -
     48D  ALA*     2.9    31.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 45 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     41D  HIS      3.2    10.5    +      -       -      +
     42D  ALA      3.6     4.5    -      -       -      +
     43D  GLN      3.2     0.2    -      -       -      -
     44D  ASP*     1.3    75.4    -      -       -      +
     46D  ALA*     1.3    60.2    +      -       -      +
     48D  ALA*     3.4     4.8    +      -       -      +
     49D  LEU*     2.9    31.4    +      -       -      +
     70D  ILE*     4.8     9.7    -      -       +      +
     76D  TYR*     3.4    43.1    -      -       +      +
    133F  VAL*     4.1     9.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 46 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     42D  ALA      3.0    16.1    +      -       -      +
     43D  GLN      3.2     4.2    +      -       -      +
     45D  ALA*     1.3    76.9    -      -       -      +
     47D  THR*     1.3    59.0    +      -       -      +
     49D  LEU*     3.3     0.7    +      -       -      +
     50D  ALA*     2.8    31.4    +      -       -      +
    117F  GLY      3.7    21.1    -      -       -      +
    118F  ASP*     3.8    19.1    -      -       -      -
    119F  ALA*     3.5     4.2    -      -       -      +
    131F  VAL*     4.0    11.1    -      -       -      +
    133F  VAL*     3.7    14.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with THR 47 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     43D  GLN*     2.9    35.6    +      -       -      +
     44D  ASP*     3.8     7.0    -      -       -      -
     46D  ALA*     1.3    78.1    -      -       -      +
     48D  ALA*     1.3    62.2    +      -       -      +
     50D  ALA*     3.5     2.5    +      -       -      +
     51D  LEU*     3.1    23.7    +      -       +      +
    119F  ALA*     3.8    11.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 48 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     44D  ASP      2.9    19.1    +      -       -      +
     45D  ALA*     3.9     5.6    -      -       -      +
     47D  THR*     1.3    78.8    -      -       -      +
     49D  LEU*     1.3    56.5    +      -       -      +
     51D  LEU*     3.3    10.4    +      -       -      +
     52D  SER*     2.9    32.0    +      -       -      +
     70D  ILE*     6.4     2.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 49 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     45D  ALA      2.9    18.6    +      -       -      +
     46D  ALA      3.9     2.7    -      -       -      +
     48D  ALA*     1.3    73.7    -      -       -      +
     50D  ALA*     1.3    66.6    +      -       -      +
     52D  SER*     3.1     7.9    +      -       -      -
     53D  LEU*     2.8    48.1    +      -       +      +
     66D  LEU*     3.8    29.8    -      -       +      +
     67D  VAL*     4.2    14.6    -      -       +      -
     70D  ILE*     4.4    16.4    -      -       +      -
     79D  ILE*     3.6    38.1    -      -       +      -
     81D  VAL*     5.1     0.4    -      -       +      -
    131F  VAL*     3.8    15.7    -      -       +      -
    133F  VAL*     5.1     1.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 50 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     46D  ALA      2.8    17.6    +      -       -      +
     47D  THR      3.8     3.1    -      -       -      +
     49D  LEU*     1.3    76.1    -      -       -      +
     51D  LEU*     1.3    61.1    +      -       -      +
     53D  LEU      3.3     0.3    +      -       -      -
     54D  THR*     2.9    28.5    +      -       -      -
    119F  ALA*     3.7    15.9    -      -       +      -
    120F  LEU      3.7    23.1    -      -       -      +
    121F  VAL*     3.6    18.8    -      -       +      +
    131F  VAL*     3.9     9.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 51 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     47D  THR*     3.1    14.8    +      -       +      +
     48D  ALA*     3.4    12.3    -      -       -      +
     49D  LEU      3.2     0.2    -      -       -      -
     50D  ALA*     1.3    77.0    -      -       -      +
     52D  SER*     1.3    63.1    +      -       -      +
     54D  THR*     3.2    16.7    +      -       -      +
     55D  PRO*     3.4    10.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with SER 52 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     48D  ALA*     2.9    17.0    +      -       -      +
     49D  LEU*     3.1    16.2    +      -       -      -
     51D  LEU*     1.3    77.8    -      -       -      +
     53D  LEU*     1.3    58.2    +      -       -      +
     55D  PRO*     3.5     6.6    -      -       -      +
     56D  ASN*     3.1    20.6    -      -       -      +
     66D  LEU*     3.6    23.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 53 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     49D  LEU*     2.8    29.7    +      -       +      +
     50D  ALA      3.8     4.0    -      -       -      +
     52D  SER*     1.3    76.7    -      -       -      +
     54D  THR*     1.3    64.6    +      -       -      +
     55D  PRO      3.4     0.2    -      -       -      -
     56D  ASN*     2.9     3.4    +      -       +      -
     57D  ILE*     2.9    32.9    +      -       +      +
     63D  VAL*     3.9    40.2    -      -       +      +
     66D  LEU*     3.9    22.7    -      -       +      -
     67D  VAL*     4.6     0.9    -      -       +      -
     81D  VAL*     4.0    25.4    -      -       +      -
    121F  VAL*     4.2     9.6    -      -       +      -
    131F  VAL*     3.9    24.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 54 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     50D  ALA      2.9    20.6    +      -       -      -
     51D  LEU*     3.6    12.8    +      -       +      +
     53D  LEU*     1.3    77.7    -      -       -      +
     55D  PRO*     1.3    69.7    -      -       +      +
     56D  ASN      3.2     1.2    +      -       -      -
     57D  ILE*     3.7    15.1    +      -       -      +
    120F  LEU      5.3     0.3    +      -       -      -
    121F  VAL*     3.6    19.8    -      -       -      +
    122F  SER      3.8    22.4    +      -       -      +
----------------------------------------------------------
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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