Contacts of the helix formed by residues 21 - 40 (chain A) in PDB entry 1S4X


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 LYS 21 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     22A  LEU*     1.3    59.0    +      -       -      +
     23A  LEU      3.4     2.0    -      -       -      -
     24A  ILE*     3.3    36.4    -      -       +      +
     25A  THR*     2.4    64.7    +      -       -      +
----------------------------------------------------------
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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
----------------------------------------------------------
     21A  LYS*     1.3    82.0    -      -       -      +
     23A  LEU*     1.3    66.6    +      -       +      +
     25A  THR*     3.6     3.4    -      -       -      -
     26A  ILE*     3.1    45.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 23 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     22A  LEU*     1.3    82.3    -      -       +      +
     24A  ILE*     1.3    61.8    +      -       +      +
     25A  THR      2.7     6.4    +      -       -      -
     26A  ILE*     3.9    18.6    -      -       +      +
     27A  HIS*     2.4    61.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 24 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     21A  LYS*     3.3    40.2    -      -       +      +
     23A  LEU*     1.3    78.2    -      -       +      +
     25A  THR*     1.3    56.6    +      -       -      +
     27A  HIS*     4.6     2.0    -      -       -      -
     28A  ASP*     2.8    38.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with THR 25 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     21A  LYS*     2.4    60.9    +      -       -      +
     22A  LEU*     3.6     4.7    -      -       -      -
     23A  LEU      2.7     0.2    +      -       -      -
     24A  ILE*     1.3    76.8    -      -       -      +
     26A  ILE*     1.3    62.9    +      -       +      +
     28A  ASP*     3.8     1.8    -      -       -      -
     29A  ARG*     2.8    37.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 26 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     22A  LEU*     3.1    39.2    +      -       +      +
     23A  LEU*     2.8    19.8    +      -       +      +
     25A  THR*     1.3    75.9    -      -       +      +
     27A  HIS*     1.3    64.9    +      -       +      +
     28A  ASP      3.0     5.8    +      -       -      -
     29A  ARG*     3.4    51.9    +      -       -      +
     30A  LYS*     3.7     8.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 27 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     23A  LEU*     2.4    51.1    +      -       +      +
     24A  ILE*     4.6     1.1    -      -       -      -
     26A  ILE*     1.3    76.7    -      -       +      +
     28A  ASP*     1.3    64.9    +      -       -      +
     30A  LYS*     4.2    10.8    -      -       -      +
     31A  GLU*     5.9     0.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 28 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24A  ILE*     2.8    33.9    +      -       -      +
     25A  THR*     3.6     1.7    +      -       -      +
     26A  ILE      3.0     0.4    -      -       -      -
     27A  HIS*     1.3    91.6    +      -       -      +
     29A  ARG*     1.3    54.4    +      -       -      +
     30A  LYS*     2.5    18.4    +      -       -      +
     31A  GLU*     2.9    25.1    +      -       +      +
     32A  PHE*     4.0     0.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 29 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     25A  THR*     2.8    29.8    +      -       +      +
     26A  ILE*     3.4    47.1    +      -       -      +
     28A  ASP*     1.3    75.4    -      -       -      +
     30A  LYS*     1.3    56.6    +      -       -      +
     31A  GLU      3.1     0.2    -      -       -      -
     32A  PHE*     2.8    17.6    +      -       +      -
     33A  ALA*     2.4    43.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 30 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     26A  ILE      3.7     6.8    +      -       -      +
     27A  HIS*     4.2    13.5    -      -       -      +
     28A  ASP      2.5     6.8    +      -       -      +
     29A  ARG*     1.3    78.0    -      -       -      +
     31A  GLU*     1.3    60.7    +      -       -      +
     33A  ALA*     3.1    12.8    +      -       +      +
     34A  LYS*     2.6    44.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 31 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27A  HIS      5.9     0.2    -      -       -      +
     28A  ASP*     2.9    13.4    +      -       +      +
     30A  LYS*     1.3    86.5    -      -       +      +
     32A  PHE*     1.3    52.6    +      -       +      +
     34A  LYS*     2.7    10.1    +      -       -      +
     35A  PHE*     2.5    63.2    +      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 32 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     28A  ASP      4.0     0.8    +      -       -      -
     29A  ARG*     2.8    22.4    +      -       +      +
     31A  GLU*     1.3    76.9    -      -       +      +
     33A  ALA*     1.3    66.1    +      -       -      +
     35A  PHE*     3.6     8.9    -      +       +      +
     36A  GLU*     2.8    26.7    +      -       -      +
     39A  ARG*     5.1    17.3    -      -       -      -
     42A  ALA*     4.6    21.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 33 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     29A  ARG*     2.4    33.6    +      -       +      +
     30A  LYS*     3.4    16.2    -      -       +      +
     32A  PHE*     1.3    73.1    -      -       -      +
     34A  LYS*     1.3    55.8    +      -       -      +
     36A  GLU*     2.6    40.7    -      -       -      +
     43A  LYS*     5.4     0.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 34 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30A  LYS*     2.6    23.7    +      -       +      +
     31A  GLU*     2.7    16.2    +      -       -      +
     33A  ALA*     1.3    73.7    -      -       -      +
     35A  PHE*     1.3    64.0    +      -       +      +
     36A  GLU*     2.5    16.9    +      -       -      +
     37A  GLU*     3.0    35.9    +      -       +      +
     38A  GLU*     5.8     4.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 35 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31A  GLU*     2.5    56.8    +      -       +      +
     32A  PHE*     4.0     8.7    -      +       +      +
     34A  LYS*     1.3    80.3    -      -       +      +
     36A  GLU*     1.3    64.0    +      -       -      +
     37A  GLU      3.1     0.7    -      -       -      -
     38A  GLU*     2.8    48.9    +      -       -      +
     39A  ARG*     3.3    16.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 36 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     32A  PHE*     2.8    11.8    +      -       -      +
     33A  ALA*     2.6    38.6    -      -       -      +
     34A  LYS      2.5     6.6    +      -       -      +
     35A  PHE*     1.3    73.1    -      -       -      +
     37A  GLU*     1.3    75.4    +      -       +      +
     38A  GLU      2.7     0.2    +      -       -      -
     39A  ARG*     4.7     0.9    -      -       -      -
     40A  ALA*     2.3    48.6    +      -       +      +
     43A  LYS*     3.1    31.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 37 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     34A  LYS*     3.0    28.2    +      -       +      +
     36A  GLU*     1.3    87.9    -      -       +      +
     38A  GLU*     1.3    63.9    +      -       +      +
     40A  ALA*     4.6     3.1    +      -       -      +
     41A  ARG*     4.7     2.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 38 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     34A  LYS*     5.8     4.3    +      -       -      +
     35A  PHE*     2.8    39.6    +      -       -      +
     36A  GLU      2.7     4.2    +      -       -      -
     37A  GLU*     1.3    80.2    -      -       +      +
     39A  ARG*     1.3    55.6    +      -       +      +
     40A  ALA      3.5     0.2    -      -       -      -
     41A  ARG*     2.4    32.2    +      -       -      -
     51A  LEU*     3.6     7.4    -      -       -      +
     55A  ALA*     4.0    29.4    -      -       +      +
     58A  THR*     4.9    14.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 39 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     32A  PHE*     5.1    17.5    -      -       -      -
     35A  PHE*     3.9    19.1    -      -       +      +
     36A  GLU*     3.2     1.1    +      -       -      -
     38A  GLU*     1.3    77.1    -      -       +      +
     40A  ALA*     1.3    48.9    -      -       -      +
     41A  ARG*     1.8    45.0    +      -       -      +
     42A  ALA*     2.9    26.2    +      -       -      +
     46A  THR*     4.4     8.9    +      -       -      +
     52A  TYR*     3.7    46.1    +      -       +      -
     55A  ALA*     4.0    17.6    -      -       +      +
     56A  THR*     5.3    11.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 40 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     36A  GLU*     2.3    54.8    +      -       +      +
     37A  GLU*     4.6     2.9    -      -       -      +
     38A  GLU      3.5     1.0    -      -       -      -
     39A  ARG*     1.3    59.1    -      -       -      +
     41A  ARG*     1.3    54.3    +      -       +      +
     42A  ALA*     3.3     2.2    -      -       -      +
     43A  LYS*     2.8    22.5    -      -       +      +
     44A  TRP*     2.6    38.8    +      -       +      +
----------------------------------------------------------
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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