Contacts of the helix formed by residues 2 - 35 (chain B) in PDB entry 1WFB


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 THR 2 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24A  THR*     4.5     0.9    -      -       +      +
     25A  ALA*     3.5    37.7    -      -       +      +
     28A  ALA*     3.7    24.8    -      -       +      +
     29A  ALA*     5.1     1.5    -      -       +      +
      1B  ASP*     1.4    74.0    -      -       -      +
      3B  ALA*     1.3    52.7    +      -       -      +
      5B  ASP*     3.3     8.9    +      -       +      +
      6B  ALA*     2.8    33.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 3 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      1B  ASP*     3.3    13.2    +      -       -      +
      2B  THR*     1.3    76.3    -      -       -      +
      4B  SER*     1.3    61.3    +      -       -      +
      6B  ALA*     3.9     5.3    -      -       -      +
      7B  ALA*     3.1    23.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 4 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      1B  ASP*     3.1    23.7    +      -       -      -
      3B  ALA*     1.3    74.4    -      -       -      +
      5B  ASP*     1.3    63.7    +      -       -      +
      7B  ALA*     3.3     6.8    +      -       -      +
      8B  ALA*     2.9    29.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 5 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24A  THR*     3.9    14.2    -      -       +      +
      1B  ASP      3.0    25.6    +      -       -      +
      2B  THR*     3.7     7.4    -      -       -      +
      4B  SER*     1.3    80.4    -      -       -      +
      6B  ALA*     1.3    56.6    +      -       -      +
      8B  ALA*     3.3     6.0    +      -       -      +
      9B  ALA*     2.9    28.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 6 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     21A  ALA*     3.5    38.3    -      -       +      +
     24A  THR*     3.8    11.2    -      -       -      +
     25A  ALA*     4.3    14.4    -      -       +      +
      2B  THR      2.8    22.5    +      -       -      +
      3B  ALA*     3.9     5.6    -      -       -      +
      5B  ASP*     1.3    72.5    -      -       -      +
      7B  ALA*     1.3    57.6    +      -       -      +
      9B  ALA*     3.3     1.7    +      -       -      +
     10B  ALA*     3.0    23.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 7 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     21A  ALA*     5.4     0.2    -      -       -      -
      3B  ALA      3.1    17.7    +      -       -      +
      4B  SER*     3.6     9.0    -      -       -      +
      5B  ASP      3.3     0.2    -      -       -      -
      6B  ALA*     1.3    77.0    -      -       -      +
      8B  ALA*     1.3    61.4    +      -       -      +
     10B  ALA*     3.3     7.2    +      -       -      +
     11B  ALA*     3.0    24.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 8 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      4B  SER      2.9    17.7    +      -       -      +
      5B  ASP*     3.3     6.7    +      -       -      +
      7B  ALA*     1.3    74.8    -      -       -      +
      9B  ALA*     1.4    57.2    +      -       -      +
     11B  ALA*     3.8     5.9    -      -       -      +
     12B  LEU*     2.9    33.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 9 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     20A  ALA*     4.0    11.4    -      -       +      +
     24A  THR*     3.3    27.8    -      -       +      +
      5B  ASP      2.9    16.2    +      -       -      +
      6B  ALA      3.6     5.2    -      -       -      +
      7B  ALA      3.3     0.2    -      -       -      -
      8B  ALA*     1.4    75.7    -      -       -      +
     10B  ALA*     1.3    54.5    +      -       -      +
     12B  LEU*     3.9     4.7    -      -       -      +
     13B  THR*     2.7    38.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 10 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     17A  ALA*     3.4    36.3    -      -       +      +
     18A  LYS*     5.5     0.2    -      -       -      -
     20A  ALA*     4.2     1.0    -      -       -      +
     21A  ALA*     4.0     8.1    -      -       +      -
      6B  ALA      3.0    14.2    +      -       -      +
      7B  ALA*     3.3    11.4    +      -       -      +
      9B  ALA*     1.3    76.5    -      -       -      +
     11B  ALA*     1.3    56.7    +      -       -      +
     13B  THR*     3.5     0.5    +      -       -      -
     14B  ALA*     2.9    31.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 11 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      7B  ALA      3.0    17.3    +      -       -      +
      8B  ALA*     3.8     5.8    -      -       -      +
     10B  ALA*     1.3    75.7    -      -       -      +
     12B  LEU*     1.3    58.1    +      -       -      +
     14B  ALA*     3.4     6.1    +      -       -      +
     15B  ALA*     3.0    29.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 12 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      8B  ALA      2.9    17.6    +      -       -      +
      9B  ALA*     4.0     4.0    -      -       -      +
     11B  ALA*     1.3    76.9    -      -       -      +
     13B  THR*     1.3    63.2    +      -       -      +
     15B  ALA*     3.3     8.4    +      -       +      +
     16B  ASN*     2.9    51.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 13 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     16A  ASN*     3.4    42.4    -      -       +      +
     17A  ALA*     3.9     1.1    -      -       -      +
     20A  ALA*     3.3    15.2    -      -       +      +
      9B  ALA*     2.7    23.0    +      -       -      +
     10B  ALA      3.7     3.4    -      -       -      -
     12B  LEU*     1.3    77.3    -      -       -      +
     14B  ALA*     1.3    56.2    +      -       -      +
     16B  ASN*     3.3     9.2    +      -       -      +
     17B  ALA*     2.9    28.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 14 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     13A  THR*     3.8    22.2    -      -       +      +
     17A  ALA*     3.9    15.4    -      -       +      +
     10B  ALA      2.9    22.6    +      -       -      +
     11B  ALA*     3.7     6.1    -      -       -      +
     13B  THR*     1.3    69.7    -      -       -      +
     15B  ALA*     1.3    60.8    +      -       -      +
     17B  ALA*     3.2     3.8    +      -       -      +
     18B  LYS*     2.9    29.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 15 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     11B  ALA      3.0    17.9    +      -       -      +
     12B  LEU*     3.3    11.0    +      -       +      +
     14B  ALA*     1.3    75.4    -      -       -      +
     16B  ASN*     1.3    60.7    +      -       -      +
     18B  LYS*     3.3     7.4    +      -       -      +
     19B  ALA*     2.9    28.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 16 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12B  LEU*     2.9    43.9    +      -       -      +
     13B  THR*     3.7     7.1    -      -       -      +
     15B  ALA*     1.3    77.6    -      -       -      +
     17B  ALA*     1.3    58.3    +      -       -      +
     19B  ALA*     3.3     8.2    +      -       -      +
     20B  ALA*     3.0    27.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 17 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12A  LEU*     5.3     1.8    -      -       +      -
     13A  THR*     3.4    34.8    +      -       +      +
     16A  ASN*     5.4     9.0    -      -       +      +
     13B  THR*     2.9    16.8    +      -       +      +
     14B  ALA*     3.5     4.3    -      -       -      +
     16B  ASN*     1.3    77.0    -      -       -      +
     18B  LYS*     1.3    55.2    +      -       -      +
     20B  ALA*     3.2    10.0    +      -       -      +
     21B  ALA*     3.0    26.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 18 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     13A  THR*     4.2     7.5    +      -       +      +
     14B  ALA      2.9    16.3    +      -       -      +
     15B  ALA*     3.6     7.9    -      -       -      +
     17B  ALA*     1.3    71.2    -      -       -      +
     19B  ALA*     1.3    65.1    +      -       -      +
     21B  ALA*     3.1    14.8    +      -       +      +
     22B  GLU*     2.9    48.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 19 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     15B  ALA      2.9    15.0    +      -       -      +
     16B  ASN*     3.3    13.4    +      -       -      +
     18B  LYS*     1.3    75.5    -      -       -      +
     20B  ALA*     1.3    60.7    +      -       -      +
     22B  GLU*     3.2    16.4    +      -       -      +
     23B  LEU*     2.9    37.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 20 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     16B  ASN      3.0    13.3    +      -       -      +
     17B  ALA*     3.2    11.9    +      -       -      +
     19B  ALA*     1.3    74.8    -      -       -      +
     21B  ALA*     1.3    56.8    +      -       -      +
     23B  LEU*     3.4     8.3    +      -       -      +
     24B  THR*     2.8    33.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 21 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      9A  ALA*     4.3    23.6    -      -       +      -
     13A  THR*     5.7     1.6    -      -       -      +
     17B  ALA      3.0    14.0    +      -       -      +
     18B  LYS*     3.1    19.0    +      -       +      +
     20B  ALA*     1.3    76.2    -      -       -      +
     22B  GLU*     1.3    56.5    +      -       +      +
     24B  THR*     3.3     7.6    +      -       -      -
     25B  ALA*     2.9    30.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 22 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     18B  LYS*     2.9    37.5    +      -       -      +
     19B  ALA*     3.5    24.5    +      -       -      +
     21B  ALA*     1.3    74.9    -      -       -      +
     23B  LEU*     1.3    61.7    +      -       +      +
     25B  ALA*     3.3     6.2    +      -       -      +
     26B  ALA*     2.9    29.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 23 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19B  ALA*     2.9    32.7    +      -       +      +
     20B  ALA*     3.6    10.8    -      -       -      +
     22B  GLU*     1.3    83.1    -      -       +      +
     24B  THR*     1.3    63.6    +      -       -      +
     26B  ALA*     3.4     6.5    +      -       +      +
     27B  ASN*     3.0    25.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 24 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      5A  ASP*     6.1     2.0    -      -       +      +
     20B  ALA*     2.8    19.6    +      -       -      +
     21B  ALA*     3.5     7.7    -      -       -      -
     22B  GLU      3.3     0.2    -      -       -      -
     23B  LEU*     1.3    76.3    -      -       -      +
     25B  ALA*     1.3    57.6    +      -       -      +
     27B  ASN*     3.2     6.2    +      -       -      +
     28B  ALA*     2.9    33.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 25 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     21B  ALA      2.9    17.4    +      -       -      +
     22B  GLU*     3.7     7.4    -      -       -      +
     24B  THR*     1.3    74.9    -      -       -      +
     26B  ALA*     1.3    66.0    +      -       -      +
     28B  ALA*     3.4     5.5    +      -       -      +
     29B  ALA*     2.9    26.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 26 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     22B  GLU      2.9    17.4    +      -       -      +
     23B  LEU*     3.8     7.2    -      -       +      +
     25B  ALA*     1.3    74.7    -      -       -      +
     27B  ASN*     1.3    57.6    +      -       -      +
     29B  ALA*     3.4     5.4    +      -       -      +
     30B  ALA*     3.0    29.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 27 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     23B  LEU      3.0    18.6    +      -       -      +
     24B  THR*     3.5     6.3    -      -       -      +
     26B  ALA*     1.3    78.7    -      -       -      +
     28B  ALA*     1.3    56.3    +      -       -      +
     30B  ALA*     3.3     8.6    +      -       -      +
     31B  ALA*     3.0    27.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 28 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24B  THR*     2.9    21.3    +      -       +      +
     25B  ALA*     3.8     5.6    -      -       -      +
     27B  ASN*     1.3    76.9    -      -       -      +
     29B  ALA*     1.3    57.1    +      -       -      +
     31B  ALA*     3.2     8.6    +      -       -      +
     32B  ALA*     3.0    28.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 29 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     25B  ALA      2.9    17.2    +      -       -      +
     26B  ALA*     3.7     6.7    -      -       -      +
     28B  ALA*     1.3    76.8    -      -       -      +
     30B  ALA*     1.3    56.6    +      -       -      +
     32B  ALA*     3.3     7.6    +      -       -      +
     33B  ALA*     2.9    30.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 30 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     26B  ALA      3.0    14.0    +      -       -      +
     27B  ASN*     3.5    13.7    -      -       -      +
     29B  ALA*     1.3    76.7    -      -       -      +
     31B  ALA*     1.4    58.6    +      -       -      +
     33B  ALA*     3.4     5.5    +      -       -      +
     34B  ALA*     2.9    31.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 31 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27B  ASN      3.0    13.7    +      -       -      +
     28B  ALA*     3.2    12.1    +      -       -      +
     30B  ALA*     1.4    77.4    -      -       -      +
     32B  ALA*     1.3    62.4    +      -       -      +
     34B  ALA*     3.3     6.4    +      -       -      +
     35B  THR*     3.1    30.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 32 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     28B  ALA      3.0    15.9    +      -       -      +
     29B  ALA*     3.3     8.3    +      -       -      +
     31B  ALA*     1.3    75.6    -      -       -      +
     33B  ALA*     1.3    63.1    +      -       -      +
     35B  THR*     2.7    25.7    +      -       -      -
     36B  ALA*     3.5     7.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 33 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     29B  ALA      2.9    17.4    +      -       -      +
     30B  ALA*     3.8     6.5    -      -       -      +
     32B  ALA*     1.3    76.5    -      -       -      +
     34B  ALA*     1.3    62.8    +      -       -      +
     36B  ALA*     3.5     1.2    +      -       -      -
     37B  ARG*     2.9    50.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 34 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30B  ALA      2.9    17.8    +      -       -      +
     31B  ALA*     3.3     7.2    +      -       -      +
     33B  ALA*     1.3    76.6    -      -       -      +
     35B  THR*     1.3    62.1    +      -       -      +
     37B  ARG*     3.1    16.1    +      -       -      +
     38B  NH2      3.2     9.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with THR 35 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31B  ALA*     3.1    18.7    +      -       +      +
     32B  ALA*     2.7    21.7    +      -       -      -
     34B  ALA*     1.3    76.4    -      -       +      +
     36B  ALA*     1.3    61.3    +      -       -      +
     37B  ARG      3.3     0.9    +      -       -      -
     38B  NH2      3.4     7.3    +      -       -      -
----------------------------------------------------------
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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