Contacts of ligand SO4 310A in PDB entry 6F26

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 310A in PDB entry 6F26
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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
----------------------------------------------------------
     87A  PRO*     4.8    13.2    -      -       -      +
     92A  LEU*     2.9    34.3    -      -       -      +
     95A  PHE*     3.7    24.8    -      -       -      -
    290A  TRP*     3.2    38.4    +      -       -      +
    291A  ASN*     4.1     8.5    +      -       -      -
----------------------------------------------------------


Table III
List of putative hydrogen bonds between ligand SO4 310A and protein in PDB entry 6F26
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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        ASN  291A     OD1    II        4.7      1.6
  5   O4     I        TRP  290A     O      II        3.7     13.3
  5   O4     I        ASN  291A     OD1    II        4.1      6.9
------------------------------------------------------------------------


Table IV
Full list of atomic contacts with ligand SO4 310A in PDB entry 6F26
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Total number of contacts is 24
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      LEU   92A     CD2    IV        4.0       1.6  
  1   S      VI      TRP  290A     CD1     V        4.2       1.1  
  1   S      VI      PHE   95A     CE1     V        4.2       1.6  
  2   O1     I       LEU   92A     CD2    IV        4.1       5.2* 
  2   O1     I       TRP  290A     CD1     V        4.3       4.3  
  2   O1     I       ASN  291A     OD1    II        4.7       1.6  
  2   O1     I       PRO   87A     CG     IV        4.8       7.1* 
  2   O1     I       PRO   87A     CD     IV        5.1       1.7* 
  3   O2     I       PHE   95A     CE1     V        4.1       7.8  
  3   O2     I       PHE   95A     CZ      V        4.2       3.1  
  3   O2     I       PHE   95A     CD1     V        4.3       1.6  
  3   O2     I       LEU   92A     CD2    IV        4.3       2.8* 
  3   O2     I       PHE   95A     CE2     V        4.5       2.1  
  3   O2     I       PHE   95A     CG      V        4.6       0.7  
  3   O2     I       PHE   95A     CD2     V        4.7       0.3  
  3   O2     I       PRO   87A     CG     IV        5.1       4.3* 
  4   O3     I       LEU   92A     CD2    IV        2.9      24.8* 
  4   O3     I       TRP  290A     CB     IV        3.2      18.4* 
  4   O3     I       TRP  290A     CD1     V        3.2       1.2  
  4   O3     I       PHE   95A     CE1     V        3.7       2.8  
  5   O4     I       TRP  290A     O      II        3.7      13.3  
  5   O4     I       ASN  291A     OD1    II        4.1       6.9  
  5   O4     I       PHE   95A     CE1     V        4.1       3.5  
  5   O4     I       PHE   95A     CZ      V        4.4       1.4  
------------------------------------------------------------------------


Table V
Complementarity values for the ligand SO4 310A in PDB entry 6F26
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---------------------------------------------
Theoretical maximum (Å2)                 195
Actual value (Å2)                         -9
Normalised complementarity             -0.05
---------------------------------------------


Table VI
Normalised complementarity as a function of atomic substitution for ligand SO4 310A in PDB entry 6F26
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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 -0.06 -0.06 -0.06 -0.05 -0.05 -0.05 -0.05 -0.05
2 O1 I -0.05 -0.06 -0.05 0.08 0.10 0.10 0.10 0.08
3 O2 I -0.05 -0.05 -0.05 0.02 0.02 0.02 0.02 0.02
4 O3 I -0.05 -0.05 -0.05 0.39 0.39 0.39 0.39 0.39
5 O4 I -0.05 -0.26 -0.05 -0.26 -0.05 -0.05 -0.05 -0.26


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:
Ligand C9Z  314
1. Carbon (in rings)
                     1 CC4    8 CC4    9 C03   16 C12    3 C20    4 C21
                     5 C22   18 C23   17 C18    6 C24    7 C28   19 C25
                    10 C05   11 C06   15 C11   16 C12   11 C06   12 C07
                    13 C08   14 C09   20 C29   21 C30   22 C31   23 C32
                    24 C34   25 C35   29 C39   30 C40   31 C41   32 C42
                    34 C45   35 C46
2. Oxygen ("hydroxy" or "carbonyl")
                    34 O02   35 O14   44 O16
3. Nitrogen ("hydrophilic")
                    37 N04   38 N10   39 N17   40 N19   41 N27
Ligand C9Z  307
1. Carbon (in rings)
                     1 CC4    8 CC4    9 C03   16 C12    3 C20    4 C21
                     5 C22   18 C23   17 C18    6 C24    7 C28   19 C25
                    10 C05   11 C06   15 C11   16 C12   11 C06   12 C07
                    13 C08   14 C09   20 C29   21 C30   22 C31   23 C32
                    24 C34   25 C35   29 C39   30 C40   31 C41   32 C42
                    34 C45   35 C46
2. Oxygen ("hydroxy" or "carbonyl")
                    34 O02   35 O14   44 O16
3. Nitrogen ("hydrophilic")
                    37 N04   38 N10   39 N17   40 N19   41 N27


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