Contacts of the helix formed by residues 21 - 46 (chain A) in PDB entry 2FA5


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 PHE 21 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     16A  LEU*     3.6    33.7    -      -       +      -
     17A  ASN      3.2    11.6    +      -       -      +
     18A  LEU*     2.9    21.8    +      -       +      +
     19A  GLU      3.5     0.2    -      -       -      -
     20A  GLN*     1.3    74.9    -      -       -      +
     22A  LEU*     1.3    66.8    +      -       -      +
     23A  PRO*     3.7    24.2    -      -       +      -
     24A  TYR*     2.9    27.2    +      -       +      +
     25A  ARG*     3.0    12.9    +      -       -      +
     37B  ILE*     4.6     1.3    -      -       +      -
    124B  VAL*     3.7    13.7    -      -       +      -
    125B  ASN*     3.7    11.9    -      -       -      -
    128B  GLU*     3.2    45.5    -      -       +      -
    801B   CL      3.9    20.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 22 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     20A  GLN      3.6     5.9    +      -       -      -
     21A  PHE*     1.3    69.4    -      -       -      +
     23A  PRO*     1.3    80.3    -      -       +      +
     25A  ARG*     3.1     8.7    +      -       +      -
     26A  LEU*     2.8    33.6    +      -       +      +
    150A  LEU*     4.3    17.3    -      -       +      -
     33B  ILE*     4.8     0.7    -      -       +      -
    128B  GLU*     4.1    14.5    +      -       -      +
    131B  LEU*     4.7     4.5    -      -       +      -
    132B  MSE      3.7    28.5    -      -       +      -
    140B  GLN*     4.9     4.3    -      -       -      +
    143B  LEU*     4.2    12.6    -      -       +      -
    144B  GLU*     4.5    20.2    +      -       +      +
    147B  ILE*     4.0    24.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with PRO 23 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     21A  PHE*     3.5    26.9    -      -       +      -
     22A  LEU*     1.3    99.2    -      -       +      +
     24A  TYR*     1.3    55.5    +      -       -      +
     26A  LEU*     3.9     4.1    -      -       +      +
     27A  SER*     3.0    28.8    +      -       -      -
     30B  SER*     4.7     1.7    +      -       -      -
     33B  ILE*     3.9    30.8    -      -       +      +
     34B  SER*     5.7     0.3    +      -       -      -
     37B  ILE*     4.1    10.8    -      -       +      -
     53B  ARG*     5.3     4.3    -      -       -      +
    128B  GLU*     3.5    24.9    -      -       +      -
    131B  LEU*     4.4     9.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 24 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     18A  LEU*     3.3    39.0    -      -       +      +
     19A  GLU*     4.3    11.9    +      -       -      -
     21A  PHE*     2.9    20.7    +      -       +      +
     23A  PRO*     1.3    76.9    -      -       -      +
     25A  ARG*     1.3    83.3    +      -       -      +
     27A  SER*     3.1     4.9    +      -       -      -
     28A  VAL*     2.8    54.2    +      -       +      +
     53B  ARG*     3.7    42.3    -      -       -      +
     57B  ILE*     3.5    24.6    -      -       +      +
     72B  ARG*     3.7    18.4    +      -       -      +
     73B  THR*     3.7    14.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 25 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19A  GLU*     3.2    46.5    +      -       -      +
     20A  GLN*     4.7     2.5    -      -       -      +
     21A  PHE      3.0    19.1    +      -       -      +
     22A  LEU*     3.6    15.5    -      -       +      +
     24A  TYR*     1.3   103.0    -      -       -      +
     26A  LEU*     1.3    62.3    +      -       -      +
     28A  VAL*     4.0    27.6    -      -       -      +
     29A  LEU*     3.1    25.3    +      -       -      +
     72B  ARG      5.7     0.2    +      -       -      -
    144B  GLU*     6.4     1.8    -      -       +      -
    147B  ILE*     4.5    17.4    -      -       +      +
    148B  ASP*     4.6    15.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 26 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     22A  LEU*     2.8    25.3    +      -       +      +
     23A  PRO      3.9     3.8    -      -       -      +
     25A  ARG*     1.3    75.5    -      -       -      +
     27A  SER*     1.3    60.4    +      -       -      +
     29A  LEU*     3.4     6.7    +      -       +      +
     30A  SER*     2.9    32.6    +      -       -      -
    147A  ILE*     4.8     5.8    -      -       +      -
    150A  LEU*     4.9     2.2    -      -       +      -
     26B  LEU*     3.6    33.4    -      -       +      +
     29B  LEU*     3.7    30.3    -      -       +      -
     30B  SER*     4.2    15.9    -      -       -      +
     33B  ILE*     3.9    20.2    -      -       +      -
    143B  LEU*     6.5     0.2    -      -       +      -
    147B  ILE*     4.2    21.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with SER 27 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     23A  PRO      3.0    19.3    +      -       -      -
     24A  TYR*     3.1     8.7    +      -       -      -
     26A  LEU*     1.3    77.6    -      -       -      +
     28A  VAL*     1.3    59.2    +      -       -      +
     30A  SER*     3.4     1.0    +      -       -      -
     31A  ASN*     2.9    46.9    +      -       -      +
     30B  SER*     3.3    21.1    +      -       -      -
     34B  SER*     5.1     6.7    +      -       -      -
     53B  ARG*     5.4     9.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 28 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24A  TYR*     2.8    61.6    +      -       +      +
     25A  ARG*     4.0    19.3    -      -       -      +
     27A  SER*     1.3    74.3    -      -       -      +
     29A  LEU*     1.3    62.6    +      -       -      +
     31A  ASN*     3.2     2.9    +      -       -      +
     32A  ARG*     2.9    43.4    +      -       +      +
     72B  ARG      3.5    21.1    -      -       -      +
     73B  THR*     4.1    16.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 29 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     25A  ARG      3.1    18.5    +      -       -      +
     26A  LEU*     3.8     7.0    -      -       +      +
     28A  VAL*     1.3    77.9    -      -       -      +
     30A  SER*     1.3    58.3    +      -       -      +
     32A  ARG*     3.3     4.7    +      -       -      +
     33A  ILE*     2.9    49.9    +      -       +      +
     26B  LEU*     4.4     9.2    -      -       +      -
    147B  ILE*     3.8    31.6    -      -       +      +
    150B  LEU*     4.0    30.5    -      -       +      -
    151B  ALA*     4.0    33.0    -      -       +      +
    155B  LEU*     4.4     9.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 30 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     26A  LEU      2.9    19.0    +      -       -      -
     27A  SER*     3.7     6.1    -      -       -      -
     29A  LEU*     1.3    77.7    -      -       -      +
     31A  ASN*     1.3    61.6    +      -       -      +
     33A  ILE*     3.4     9.2    +      -       -      +
     34A  SER*     2.9    34.1    +      -       -      -
     23B  PRO      4.5     1.4    +      -       -      +
     26B  LEU*     4.2    21.8    -      -       -      +
     27B  SER*     3.2    32.8    +      -       -      -
     30B  SER*     4.6     3.3    -      -       -      -
----------------------------------------------------------
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Residues in contact with ASN 31 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27A  SER*     2.9    33.8    +      -       -      +
     28A  VAL      3.6     1.6    -      -       -      +
     30A  SER*     1.3    80.3    +      -       -      +
     32A  ARG*     1.3    56.0    +      -       -      +
     34A  SER*     3.5     5.9    +      -       -      -
     35A  GLY*     2.9    25.5    +      -       -      -
     49A  ILE*     5.4     1.6    -      -       -      +
     73B  THR      3.0    17.8    +      -       -      +
     74B  ALA*     3.4    33.5    +      -       +      +
     75B  MSE      3.9    15.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 32 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     28A  VAL*     2.9    34.8    +      -       -      +
     29A  LEU*     3.3     5.8    +      -       -      +
     31A  ASN*     1.3    73.9    -      -       -      +
     33A  ILE*     1.3    66.1    +      -       -      +
     35A  GLY*     3.3     1.5    +      -       -      -
     36A  ASN*     3.0    29.3    +      -       -      +
     71B  ASP      6.0     0.9    -      -       -      +
     74B  ALA*     3.7    17.9    -      -       +      -
    151B  ALA*     4.4    15.5    +      -       -      +
    152B  LYS*     5.4     6.3    -      -       -      +
    155B  LEU*     3.2    40.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 33 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     29A  LEU*     2.9    36.2    +      -       +      +
     30A  SER*     3.7     4.9    -      -       -      +
     32A  ARG*     1.3    75.8    -      -       -      +
     34A  SER*     1.3    64.2    +      -       -      +
     36A  ASN      3.2     2.1    +      -       -      -
     37A  ILE*     3.0    28.1    +      -       +      +
    131A  LEU*     3.9    28.0    -      -       +      -
     22B  LEU*     5.7     0.9    -      -       +      -
     23B  PRO*     3.8    36.8    -      -       +      -
     26B  LEU*     3.8    28.7    -      -       +      -
    150B  LEU*     4.9     4.3    -      -       +      -
    155B  LEU*     4.0    18.8    -      -       +      -
    158B  MSE      3.6     7.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with SER 34 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30A  SER*     2.9    24.1    +      -       -      -
     31A  ASN*     3.8     6.7    -      -       -      -
     33A  ILE*     1.3    80.9    -      -       -      +
     35A  GLY*     1.3    51.7    +      -       -      +
     37A  ILE*     3.3     9.0    +      -       -      +
     38A  ALA*     2.8    36.0    +      -       -      +
     41A  TYR*     4.5     1.4    +      -       -      -
     49A  ILE*     4.2    23.8    -      -       -      +
     53A  ARG*     5.6     3.5    +      -       -      -
     23B  PRO*     4.9     6.1    +      -       -      +
     27B  SER*     4.8     9.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLY 35 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31A  ASN      2.9    17.9    +      -       -      -
     32A  ARG*     3.3     2.7    +      -       -      -
     33A  ILE      3.2     0.4    -      -       -      -
     34A  SER*     1.3    76.7    -      -       -      +
     36A  ASN*     1.3    65.2    +      -       -      +
     38A  ALA*     3.3    18.0    +      -       -      +
     39A  LYS*     3.5     8.3    +      -       -      +
     49A  ILE*     4.6     7.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with ASN 36 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     32A  ARG*     3.0    17.9    +      -       -      +
     33A  ILE      3.7     4.7    -      -       -      +
     35A  GLY*     1.3    75.0    -      -       -      +
     37A  ILE*     1.3    65.6    +      -       -      +
     39A  LYS*     3.3    19.7    +      -       -      +
    127A  MSE      3.3    15.4    -      -       -      +
    155B  LEU*     3.6    31.0    -      -       -      +
    158B  MSE      3.7    26.9    -      -       +      +
    159B  ALA*     5.6     3.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 37 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     33A  ILE*     3.0    24.2    +      -       +      +
     34A  SER*     3.7     7.6    -      -       -      +
     36A  ASN*     1.3    76.3    -      -       -      +
     38A  ALA*     1.3    61.7    +      -       -      +
     39A  LYS      3.1     0.4    -      -       -      -
     40A  VAL*     3.1    22.4    +      -       -      +
     41A  TYR*     3.6    15.9    -      -       +      +
     52A  TRP*     4.9     0.4    -      -       +      -
    124A  VAL*     3.8    40.6    -      -       +      +
    127A  MSE      3.6    13.9    -      -       +      -
    128A  GLU*     5.5     1.6    -      -       +      -
    802A   CL      4.4    11.2    -      -       +      -
     21B  PHE*     4.6     2.9    -      -       +      -
     23B  PRO*     3.8    35.4    -      -       +      -
    158B  MSE      3.6    14.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 38 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     34A  SER      2.8    17.1    +      -       -      +
     35A  GLY*     3.4    11.7    -      -       -      +
     37A  ILE*     1.3    77.3    -      -       -      +
     39A  LYS*     1.3    56.6    +      -       -      +
     40A  VAL      3.2     0.2    -      -       -      -
     41A  TYR*     3.4    27.5    +      -       +      +
     42A  GLY*     2.7    29.8    +      -       -      -
     47A  MSE      4.8     0.4    -      -       -      +
     49A  ILE*     3.7    17.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 39 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     35A  GLY      3.5     7.1    +      -       -      +
     36A  ASN*     3.3    14.9    +      -       -      +
     37A  ILE      3.1     1.2    -      -       -      -
     38A  ALA*     1.3    75.6    -      -       -      +
     40A  VAL*     1.3    67.2    +      -       +      +
     42A  GLY*     4.4     1.1    -      -       -      +
     43A  ASP*     2.7    66.2    +      -       -      +
    127A  MSE      5.6     3.1    -      -       +      -
    159B  ALA*     6.0     7.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 40 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     37A  ILE      3.1    15.0    +      -       -      +
     39A  LYS*     1.3    80.3    -      -       -      +
     41A  TYR*     1.3    58.9    +      -       -      +
     43A  ASP*     4.0     1.3    -      -       -      +
     44A  ARG*     3.2    31.8    +      -       +      +
    120A  VAL*     3.7    26.5    -      -       +      +
    123A  LEU*     3.9    39.5    -      -       +      +
    124A  VAL*     4.5     7.6    -      -       +      -
    127A  MSE      3.7    31.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 41 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     34A  SER      4.5     1.9    +      -       -      -
     37A  ILE*     3.6    23.5    -      -       +      +
     38A  ALA*     3.4    17.8    +      -       +      +
     40A  VAL*     1.3    75.2    -      -       -      +
     42A  GLY*     1.3    62.3    +      -       -      +
     43A  ASP      3.2     1.3    -      -       -      -
     44A  ARG*     3.8     6.5    -      -       -      +
     45A  TYR*     2.8    30.3    +      -       +      +
     46A  GLY      3.3     4.9    +      -       -      -
     47A  MSE      3.4    46.7    +      -       +      -
     48A  ALA      3.7     9.4    -      -       -      -
     49A  ILE*     3.3    30.4    +      -       -      +
     52A  TRP*     3.3    54.9    -      +       +      +
    120A  VAL*     4.0    26.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 42 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     38A  ALA      2.7    20.9    +      -       -      -
     39A  LYS*     4.5     1.3    -      -       -      -
     41A  TYR*     1.3    78.3    -      -       -      +
     43A  ASP*     1.3    60.8    +      -       -      +
     46A  GLY*     2.9    25.4    +      -       -      -
     47A  MSE      3.7    16.4    -      -       -      -
----------------------------------------------------------
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Residues in contact with ASP 43 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39A  LYS*     2.7    56.2    +      -       -      +
     40A  VAL*     4.0     2.5    -      -       -      +
     42A  GLY*     1.3    80.6    -      -       -      +
     44A  ARG*     1.3    66.8    +      -       +      +
     45A  TYR      3.5     0.2    +      -       -      -
     46A  GLY      4.5     0.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 44 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     40A  VAL*     3.2    24.8    +      -       +      +
     43A  ASP*     1.3    81.0    -      -       +      +
     45A  TYR*     1.3    94.7    +      -       +      +
    119A  THR*     3.5    29.7    -      -       +      +
    120A  VAL*     5.1     2.0    -      -       +      -
    123A  LEU*     4.3    16.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 45 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     41A  TYR*     2.8    19.5    +      -       +      +
     44A  ARG*     1.3   101.8    +      -       +      +
     46A  GLY*     1.3    61.0    +      -       -      +
     47A  MSE      3.1    17.0    -      -       +      -
     90A  ARG*     2.8    32.3    +      -       -      +
     92A  PHE*     4.5     7.9    -      +       -      -
    115A  GLN*     4.1     3.5    +      -       -      +
    116A  VAL*     3.8    40.3    +      -       +      -
    119A  THR*     3.5    28.7    +      -       +      +
    120A  VAL*     3.6    24.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 46 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     42A  GLY*     2.9    20.2    +      -       -      -
     43A  ASP      4.5     1.6    +      -       -      -
     44A  ARG      4.0     0.2    -      -       -      -
     45A  TYR*     1.3    76.4    -      -       -      +
     47A  MSE      1.3    58.5    +      -       -      +
     48A  ALA      4.3     0.5    +      -       -      -
     51A  GLU*     4.7     0.9    -      -       -      +
     90A  ARG*     3.2    14.4    +      -       -      -
----------------------------------------------------------
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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