Contacts of ligand SO4 802B in PDB entry 1OSB

Ligand-Protein Contacts (LPC) are derived with the LPC 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.


On this page you will find:

Table II
Residues in contact with ligand SO4 802B in PDB entry 1OSB
(back to top of page)
Legend:
Dist - nearest distance (Å) between atoms of the ligand and the residue
Surf - contact surface area (Å2) between the ligand and the residue
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 contacting ligand by their side chain
       (including CA atoms)

----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue      Dist    Surf    HB    Arom    Phob    DC
----------------------------------------------------------
     17A  SER      4.9     2.1    +      -       -      -
     18A  TYR*     4.2    14.0    -      -       -      -
     21A  ASP*     4.5     2.6    +      -       -      -
    150A  HIS*     3.0    37.9    +      -       -      +
    161A  HIS*     2.5    35.2    +      -       -      -
    163A  HIS*     3.2    13.0    +      -       -      -
    803A  SO4      3.7    14.7    +      -       -      -
     25B    T*     3.1    59.4    +      -       -      +
----------------------------------------------------------


Table III
List of putative hydrogen bonds between ligand SO4 802B and protein in PDB entry 1OSB
(back to top of page)
Legend:
N     - ligand atom number in PDB entry
Dist  - distance (Å) between the ligand and protein atoms
Surf  - contact surface area (Å2) between the ligand and protein atoms
------------------------------------------------------------------------
    Ligand atom            Protein atom
-----------------   ----------------------------    Dist     Surf
  N   Name   Class    Residue       Name   Class
------------------------------------------------------------------------
  2   O1     I        HIS  150A     NE2    I         3.0     28.8
  2   O1     I        HIS  163A     NE2    I         3.6      2.6
  2   O1     I        ASP   21A     OD2    II        4.5      0.9
  2   O1     I        SER   17A     O      II        4.9      2.1
  3   O2     I          T   25B     C1'    I         3.4      0.3
  3   O2     I        HIS  163A     NE2    I         3.6      2.9
  4   O3     I          T   25B     N3     III       3.4      0.5
  4   O3     I        SO4  803A     O1     I         3.7     13.7
  4   O3     I        SO4  803A     O4     I         3.8      1.0
  4   O3     I        ASP   21A     OD2    II        4.6      1.7
  5   O4     I        HIS  161A     NE2    I         2.5     34.3
  5   O4     I        HIS  163A     NE2    I         3.2      5.2
------------------------------------------------------------------------


Table IV
Full list of atomic contacts with ligand SO4 802B in PDB entry 1OSB
(back to top of page)
Total number of contacts is 30
Legend:
N     - ligand atom number in PDB entry
Dist  - distance (A) between the ligand and protein atoms
Surf  - contact surface area (A**2) between the ligand and protein atoms
*     - indicates destabilizing contacts
------------------------------------------------------------------------
    Ligand atom            Protein atom
-----------------   ----------------------------    Dist     Surf
  N   Name   Class    Residue       Name   Class
------------------------------------------------------------------------
  1   S      VI        T   25B     N1      V        3.6       1.3  
  1   S      VI      HIS  163A     NE2    I         3.6       1.3  
  1   S      VI      HIS  150A     CG      V        3.9       1.3  
  2   O1     I       HIS  150A     NE2    I         3.0      28.8  
  2   O1     I       HIS  150A     CE1     V        3.0       5.7  
  2   O1     I       HIS  150A     CD2     V        3.0       1.4  
  2   O1     I       HIS  163A     NE2    I         3.6       2.6  
  2   O1     I       HIS  163A     CD2     V        3.8       0.9  
  2   O1     I       TYR   18A     CD2     V        4.4       4.2  
  2   O1     I       ASP   21A     OD2    II        4.5       0.9  
  2   O1     I       TYR   18A     CA     VII       4.8       0.3  
  2   O1     I       SER   17A     O      II        4.9       2.1  
  3   O2     I         T   25B     C6      V        3.1      17.5  
  3   O2     I         T   25B     N1      V        3.2       1.4  
  3   O2     I         T   25B     C2'    IV        3.3       7.3* 
  3   O2     I         T   25B     C1'    I         3.4       0.3  
  3   O2     I       HIS  163A     NE2    I         3.6       2.9  
  3   O2     I       TYR   18A     CE2     V        4.2       9.2  
  3   O2     I       TYR   18A     CD2     V        4.4       0.3  
  4   O3     I         T   25B     C4      V        3.2      22.7  
  4   O3     I         T   25B     C5      V        3.3       1.6  
  4   O3     I         T   25B     N3     III       3.4       0.5  
  4   O3     I       SO4  803A     O1     I         3.7      13.7  
  4   O3     I       SO4  803A     O4     I         3.8       1.0  
  4   O3     I       ASP   21A     OD2    II        4.6       1.7  
  5   O4     I       HIS  161A     NE2    I         2.5      34.3  
  5   O4     I       HIS  163A     NE2    I         3.2       5.2  
  5   O4     I         T   25B     C2      V        3.3       6.8  
  5   O4     I       HIS  161A     CE1     V        3.3       0.9  
  5   O4     I       HIS  150A     CB     IV        3.7       0.7* 
------------------------------------------------------------------------


Table V
Complementarity values for the ligand SO4 802B in PDB entry 1OSB
(back to top of page)

---------------------------------------------
Theoretical maximum (Å2)                 194
Actual value (Å2)                        162
Normalised complementarity              0.84
---------------------------------------------


Table VI
Normalised complementarity as a function of atomic substitution for ligand SO4 802B in PDB entry 1OSB
(back to top of page)

Legend:
N- ligand atom number in PDB entry
Bold - indicates atomic substitution which could stabilize the complex
Italics- indicates atomic substitution which could destabilize the complex
Ligand atomAtom class
NTypeClassI IIIIIIVV VIVIIVIII
1 S VI 0.84 0.84 0.84 0.82 0.84 0.84 0.84 0.84
2 O1 I 0.84 0.81 0.83 0.48 0.84 0.84 0.83 0.81
3 O2 I 0.84 0.84 0.84 0.88 0.91 0.91 0.91 0.91
4 O3 I 0.84 0.82 0.83 0.66 0.84 0.84 0.83 0.82
5 O4 I 0.84 0.84 0.84 0.44 0.84 0.84 0.84 0.84


A short description of the analytical approach (back to top of page)

The analysis of ligand-protein contacts used in this page is based upon the surface complementarity approach developed in: Sobolev V., Wade R.C., Vriend G. and Edelman M. PROTEINS (1996) 25, 120-129.
The complementarity function therein is defined as:

CF=Sl-Si-E

Where Sl is the sum of all surface areas of legitimate atomic contacts between ligand and receptor, Si is the sum of all surface areas of illegitimate atomic contacts, and E is a repulsion term.

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 ligands are automatically assigned based on the atomic coordinates. However, in three cases the automatic assignment is currently ambiguous (due to low resolution). In these three cases, the user is advised to manually analyze the full list of contacts (Table IV).
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).

IN YOUR STRUCTURE, the following atoms fall in these ambiguous cases:

NONE.

Please E-mail any questions and/or suggestions concerning this page to Vladimir.Sobolev@weizmann.ac.il