Contacts of ligand PEG1151A in PDB entry 3ZG1

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 PEG1151A in PDB entry 3ZG1
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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
----------------------------------------------------------
     46A  HIS*     3.4    37.5    +      -       -      -
     47A  GLU*     3.3    29.2    +      -       -      +
     56A  ARG*     3.8    14.2    +      -       -      -
     59A  LEU*     4.5     3.8    +      -       -      +
     60A  GLU*     3.5    36.5    +      -       -      +
     63A  GLU*     3.2    39.8    -      -       -      +
----------------------------------------------------------


Table III
List of putative hydrogen bonds between ligand PEG1151A and protein in PDB entry 3ZG1
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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        HIS   46A     NE2    I         3.9      2.1
  2   O1     I        LEU   59A     O      II        4.5      0.3
  2   O1     I        GLU   60A     N      III       4.6      0.3
  2   O1     I        GLU   47A     OE2    II        4.9      2.1
  2   O1     I        ARG   56A     NH1    III       5.5      0.7
  7   O4     I        GLU   47A     OE2    II        3.3     10.6
------------------------------------------------------------------------


Table IV
Full list of atomic contacts with ligand PEG1151A in PDB entry 3ZG1
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Total number of contacts is 32
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   C1     VI      HIS   46A     NE2    I         3.5      13.2  
  1   C1     VI      GLU   63A     CG     IV        3.6      17.7  
  1   C1     VI      GLU   63A     CB     IV        3.9       2.5  
  1   C1     VI      HIS   46A     CD2     V        4.1       1.1  
  1   C1     VI      GLU   63A     CD     VI        4.1       1.1  
  1   C1     VI      GLU   63A     OE1    II        4.4       0.7  
  2   O1     I       GLU   63A     CG     IV        3.2      15.1* 
  2   O1     I       GLU   60A     CG     IV        3.7      11.8* 
  2   O1     I       HIS   46A     NE2    I         3.9       2.1  
  2   O1     I       GLU   60A     CA     VII       4.2       0.3  
  2   O1     I       HIS   46A     CD2     V        4.3       1.2  
  2   O1     I       LEU   59A     O      II        4.5       0.3  
  2   O1     I       GLU   60A     N      III       4.6       0.3  
  2   O1     I       LEU   59A     C      VI        4.7       0.5  
  2   O1     I       GLU   47A     OE2    II        4.9       2.1  
  2   O1     I       LEU   59A     CD1    IV        5.2       2.1* 
  2   O1     I       LEU   59A     CB     IV        5.3       0.9* 
  2   O1     I       ARG   56A     NH1    III       5.5       0.7  
  3   C2    VIII     GLU   60A     CG     IV        4.2       9.0  
  3   C2    VIII     GLU   60A     CD     VI        4.6       0.9  
  3   C2    VIII     GLU   63A     CB     IV        4.8       2.7  
  3   C2    VIII     GLU   60A     CB     IV        4.8       1.1  
  4   O2     II      GLU   60A     OE2    II        3.5       9.2* 
  5   C3    VIII     HIS   46A     NE2    I         3.4       9.2  
  5   C3    VIII     HIS   46A     CE1     V        3.9       1.3  
  6   C4     VI      GLU   47A     OE2    II        3.6      11.7  
  6   C4     VI      ARG   56A     NH1    III       3.8      13.5  
  6   C4     VI      GLU   60A     OE2    II        4.4       3.8  
  7   O4     I       GLU   47A     OE2    II        3.3      10.6  
  7   O4     I       HIS   46A     CE1     V        3.6       9.4  
  7   O4     I       GLU   47A     CD     VI        3.8       3.6  
  7   O4     I       GLU   47A     CG     IV        3.9       1.2* 
------------------------------------------------------------------------


Table V
Complementarity values for the ligand PEG1151A in PDB entry 3ZG1
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---------------------------------------------
Theoretical maximum (Å2)                 266
Actual value (Å2)                         80
Normalised complementarity              0.30
---------------------------------------------


Table VI
Normalised complementarity as a function of atomic substitution for ligand PEG1151A in PDB entry 3ZG1
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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 C1 VI 0.15 0.15 0.15 0.20 0.30 0.30 0.30 0.30
2 O1 I 0.30 0.28 0.29 0.48 0.53 0.53 0.52 0.51
3 C2 VIII 0.21 0.21 0.21 0.30 0.30 0.30 0.30 0.30
4 O2 II 0.37 0.30 0.37 0.30 0.37 0.37 0.37 0.30
5 C3 VIII 0.30 0.30 0.30 0.23 0.30 0.30 0.30 0.30
6 C4 VI 0.30 0.19 0.20 0.08 0.30 0.30 0.20 0.19
7 O4 I 0.30 0.22 0.30 0.23 0.31 0.31 0.31 0.23


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 PEG 1149
2. Oxygen ("hydroxy" or "carbonyl")
                     2 O1     7 O4 
Ligand PEG 1150
2. Oxygen ("hydroxy" or "carbonyl")
                     2 O1     7 O4 
Ligand PEG 1151
2. Oxygen ("hydroxy" or "carbonyl")
                     2 O1     7 O4 
Ligand GOL 1149
2. Oxygen ("hydroxy" or "carbonyl")
                     2 O1     4 O2     6 O3 
Ligand GOL 1150
2. Oxygen ("hydroxy" or "carbonyl")
                     2 O1     4 O2     6 O3 
Ligand GOL 1151
2. Oxygen ("hydroxy" or "carbonyl")
                     2 O1     4 O2     6 O3 
Ligand PEG 1152
2. Oxygen ("hydroxy" or "carbonyl")
                     2 O1     7 O4 
Ligand PGE 1153
2. Oxygen ("hydroxy" or "carbonyl")
                     2 O1     7 O4 


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