Contacts of the helix formed by residues 240 - 251 (chain A) in PDB entry 2XIK


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 240 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    114A  GLU*     2.6    35.5    +      -       -      -
    239A  HIS*     1.3    74.7    -      -       -      +
    241A  LYS*     1.4    59.9    +      -       -      +
    242A  PRO*     3.4    17.6    -      -       -      +
    243A  PHE*     3.1    11.3    +      -       -      +
    244A  LYS*     3.0    25.2    +      -       -      +
    269A  PHE*     4.5     2.1    -      -       -      -
    272A  ARG*     5.2     5.6    +      -       -      -
    273A  TYR*     4.8     3.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 241 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    239A  HIS      3.8     1.0    +      -       -      -
    240A  SER*     1.4    69.8    -      -       -      +
    242A  PRO*     1.4    64.6    -      -       +      +
    244A  LYS*     3.2    12.5    +      -       +      +
    245A  GLU*     2.9    53.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with PRO 242 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    240A  SER*     3.4    16.6    -      -       -      +
    241A  LYS*     1.4    91.5    -      -       +      +
    243A  PHE*     1.4    54.3    +      -       -      +
    245A  GLU*     3.5    15.2    +      -       -      +
    246A  PHE*     3.1    21.0    +      -       -      +
    267A  HIS*     3.5     4.7    -      -       +      -
    268A  LYS*     4.6     7.4    -      -       +      -
    269A  PHE*     3.3    36.1    -      -       +      +
    272A  ARG*     3.9    27.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 243 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    114A  GLU*     3.7    24.0    -      -       +      +
    117A  ILE*     3.7    28.7    -      -       +      -
    121A  LEU*     4.4     0.9    -      -       +      -
    205A  ALA*     3.5    31.0    -      -       +      -
    209A  ALA*     3.6    23.1    -      -       +      -
    235A  LEU*     3.5    13.2    -      -       +      -
    239A  HIS*     4.1     6.5    -      -       +      -
    240A  SER*     3.1    23.0    +      -       -      +
    242A  PRO*     1.4    74.4    -      -       -      +
    244A  LYS*     1.3    66.0    +      -       -      +
    246A  PHE*     3.3     2.6    +      -       +      +
    247A  VAL*     3.2    37.1    +      -       +      +
    269A  PHE*     3.6    34.7    -      +       +      -
----------------------------------------------------------
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Residues in contact with LYS 244 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    235A  LEU*     3.5    45.6    +      -       +      +
    236A  GLU*     5.1     0.4    -      -       -      +
    237A  GLY      2.9    33.3    +      -       -      +
    239A  HIS*     3.4    25.7    +      -       -      +
    240A  SER      3.0    12.6    +      -       -      +
    241A  LYS*     3.6    12.1    -      -       +      +
    243A  PHE*     1.3    77.2    -      -       -      +
    245A  GLU*     1.4    55.7    +      -       +      +
    247A  VAL*     3.6     3.3    +      -       -      +
    248A  GLU*     3.1    28.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 245 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    241A  LYS*     2.9    39.5    +      -       +      +
    242A  PRO*     3.6    16.7    -      -       -      +
    243A  PHE      3.2     0.2    -      -       -      -
    244A  LYS*     1.4    74.6    -      -       +      +
    246A  PHE*     1.3    58.3    +      -       -      +
    248A  GLU*     3.4    16.7    +      -       -      +
    249A  ALA*     3.0    28.6    +      -       -      +
    267A  HIS*     3.9    13.5    +      -       +      +
    268A  LYS*     5.6     3.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 246 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    121A  LEU*     3.7    27.1    -      -       +      -
    125A  LEU*     4.1    12.6    -      -       +      -
    201A  LEU*     4.0    24.2    -      -       +      -
    205A  ALA*     4.3    11.7    -      -       +      -
    242A  PRO      3.1    14.1    +      -       -      +
    243A  PHE*     3.5     9.0    -      +       -      +
    245A  GLU*     1.3    74.6    -      -       -      +
    247A  VAL*     1.3    68.0    +      -       +      +
    249A  ALA*     3.3     5.4    +      -       -      +
    250A  CYS*     3.2    37.5    +      -       -      -
    264A  LEU*     3.8    19.2    -      -       +      +
    267A  HIS*     3.6    32.0    -      +       +      -
    269A  PHE*     4.0    14.6    -      +       +      -
    270A  ILE*     3.6    29.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 247 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    202A  GLY*     4.3     2.9    -      -       -      +
    205A  ALA*     3.8    27.4    -      -       +      -
    206A  ILE*     3.8    32.5    -      -       +      +
    233A  PRO      4.9     0.2    -      -       -      +
    234A  THR*     4.6     2.5    -      -       -      -
    235A  LEU*     4.0    24.7    -      -       +      +
    243A  PHE*     3.2    28.1    +      -       +      +
    244A  LYS      3.8     4.5    -      -       -      +
    246A  PHE*     1.3    78.1    -      -       +      +
    248A  GLU*     1.3    57.8    +      -       -      +
    250A  CYS*     3.1     7.0    +      -       -      +
    251A  LEU*     2.9    39.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 248 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    233A  PRO      5.9     1.6    -      -       -      -
    234A  THR*     6.1     4.6    -      -       +      +
    244A  LYS      3.1    18.4    +      -       -      +
    245A  GLU*     3.6    15.3    -      -       -      +
    246A  PHE      3.4     0.2    -      -       -      -
    247A  VAL*     1.3    78.0    -      -       -      +
    249A  ALA*     1.3    64.2    +      -       -      +
    251A  LEU*     3.5    19.8    +      -       -      +
    252A  ASN*     4.0     5.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 249 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    245A  GLU      3.0    14.3    +      -       -      +
    246A  PHE*     3.4    12.8    -      -       -      +
    247A  VAL      3.3     0.2    -      -       -      -
    248A  GLU*     1.3    76.7    -      -       -      +
    250A  CYS*     1.3    62.3    +      -       -      +
    252A  ASN*     4.1     7.3    +      -       -      +
    257A  PHE      4.4     2.4    -      -       -      +
    258A  ARG*     3.9     6.8    -      -       -      -
    259A  PRO*     3.4    33.7    -      -       +      +
    264A  LEU*     4.5     6.7    -      -       +      -
    267A  HIS*     4.7     8.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with CYS 250 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    198A  ILE*     3.5    27.1    -      -       -      +
    199A  TRP*     3.7     8.5    +      -       -      -
    201A  LEU*     4.1     5.6    -      -       -      -
    202A  GLY*     3.5    19.7    -      -       -      -
    246A  PHE*     3.2    32.1    +      -       -      -
    247A  VAL      3.1     4.8    +      -       -      +
    249A  ALA*     1.3    79.6    -      -       -      +
    251A  LEU*     1.3    58.0    +      -       -      +
    252A  ASN      3.3     5.3    +      -       -      -
    258A  ARG*     3.3    22.7    -      -       -      -
    264A  LEU*     3.7    30.3    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 251 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    199A  TRP*     3.2    55.2    -      -       +      +
    202A  GLY*     3.9    10.1    -      -       -      +
    203A  ILE*     3.9    15.9    -      -       +      -
    206A  ILE*     3.7    25.8    -      -       +      -
    232A  PRO*     3.1    27.7    -      -       +      +
    233A  PRO*     3.5    29.8    -      -       +      +
    247A  VAL*     2.9    22.5    +      -       +      +
    248A  GLU*     3.7    10.3    -      -       -      +
    249A  ALA      3.5     0.6    -      -       -      -
    250A  CYS*     1.3    74.1    -      -       -      +
    252A  ASN*     1.3    58.8    +      -       -      +
----------------------------------------------------------
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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