JenaLib Home    
[JenaLib Home]     [Helix Analysis Home]     [Image Library Entry]     [Sequence, Chains, Units]     [Bending Analysis Entry]     [Bending Classification]   

Analysis of nucleic acid double helix geometry

Title CRYSTAL STRUCTURE OF TANDEM ZIF268 MOLECULES COMPLEXED TO DNA
PDB code 1P47   (PDB summary)
NDB code PD0424 (NDB atlas)
Duplex length 21 base pairs
Protein Early growth response protein 1 (EGR-1) (Krox-24 protein) (ZIF268) (Nerve growth factor-induced protein A) (NGFI-A), Transcription Factor, DNA binding domain: Zinc finger|alpha-helix|beta-barrel, DNA binding domain: Zinc finger

Only the nucleic acid double helix part of the structure is analysed here. Small ligands, proteins, and overhanging ends are not taken into account. Information on the complete structure is available at the Image Library Entry page and at the Sequence, Chains, Units page.

Strand 1    5' T2 G3 G4 C5 G6 T7 G8 G9 G10 C11 G12 G13 C14 G15 T16 G17 G18 G19 C20 G21 T22 3'
Strand 2    3' A63 C62 C61 G60 C59 A58 C57 C56 C55 G54 C53 C52 G51 C50 A49 C48 C47 C46 G45 C44 A43 5'

Side view 1 Top view
Side view 1 Top view
Side view 2 3-dimensional interactive models
(Help)
  

RASMOL, CHIME, VRML 2.0, PDB

Side view 2  

Figure 1   Three orthogonal views of the double helix (Help). Residues are colored according to the nucleotide type (Help: Color codes). The curvilinear helical axis (green) was calculated with CURVES. The double helix is oriented with respect to the principle axis of inertia of the curvilinear helical axis (see Help for further explanations). This drawing reveals immediately if there is any bending of the helical axis.


Analysis of helical axis bending


Inter base pair parameters

The six inter base pair parameters (rise, shift, slide, twist, roll, tilt) describe the translational and rotational displacement between neighbouring base pairs. See Help for further explanations.

Plot of inter base pair parameters with respect to global and local helical axes:  PDF,   GIF
(Global parameters from CURVES,  local parameters from CURVES and FREEHELIX)

Table 1.  Inter base pair parameters with respect to the global helical axis, calculated with CURVES.


  Strand 1      Strand 2        riseg          shiftg          slideg          twistg         rollg         tiltg    
    / Å / Å / Å      

T2 A63            
    3.2 0.5 0.1 31° -4°
G3 C62            
    3.4 -0.5 -0.1 40° -2° -2°
G4 C61            
    2.9 1.0 -0.3 26° -1°
C5 G60            
    3.3 -0.7 0.5 38° -3°
G6 C59            
    3.0 1.0 -0.3 24°
T7 A58            
    3.5 -0.7 0.4 36° -3° -8°
G8 C57            
    3.3 -0.0 -0.5 32° -1°
G9 C56            
    3.2 -0.1 0.1 41°
G10 C55            
    3.2 1.0 -0.2 27° -8°
C11 G54            
    3.4 -0.8 0.4 34° -7°
G12 C53            
    3.3 0.1 -0.4 35° -1° -0°
G13 C52            
    3.1 0.7 -0.2 23° -0° -1°
C14 G51            
    3.2 -0.7 0.5 39° -5°
G15 C50            
    3.2 1.0 -0.4 25°
T16 A49            
    3.7 -0.6 0.2 37° -2° -6°
G17 C48            
    3.1 -0.4 -0.4 34°
G18 C47            
    3.1 0.3 -0.1 34° -1°
G19 C46            
    3.2 0.9 -0.3 29° -3°
C20 G45            
    3.4 -1.0 0.2 37° -5°
G21 C44            
    3.1 0.7 -0.3 23°
T22 A43            


Backbone parameters

Table 2.  Selected torsional angles and sugar pucker phase angles describing the conformation of the sugar phosphate backbone. (See Help for further explanations.)


 gamma     epsilon-zeta       pucker        chi      Strand 1     Strand 2      chi        pucker       epsilon-zeta     gamma 

    C2'-endo -106° T2 A63 -90° C2'-endo    
 76°   -104° (BI)             -90° (BI)   50° 
    C2'-endo -102° G3 C62 -126° C1'-exo    
 52°   -80° (BI)             -63° (BI)   41° 
    C1'-exo -117° G4 C61 -99° C2'-endo    
 46°   -56° (BI)             66° (BII)   27° 
    C1'-exo -114° C5 G60 -99° C2'-endo    
 37°   31° (BII)             -69° (BI)   48° 
    C2'-endo -132° G6 C59 -125° C1'-exo    
 34°   -67° (BI)             -87° (BI)   52° 
    C1'-exo -101° T7 A58 -123° O1'-endo    
 40°   39° (BII)             -63° (BI)   -142° 
    C2'-endo -132° G8 C57 -136° C2'-endo    
 42°   -39° (BI)             -29° (BI)   60° 
    C1'-exo -130° G9 C56 -140° C2'-endo    
 34°   -53° (BI)             -71° (BI)   -164° 
    C2'-endo -109° G10 C55 -162° C3'-endo    
 36°   -75° (BI)             59° (BII)   64° 
    C2'-endo -92° C11 G54 -105° C1'-exo    
 20°   19° (BI)             -72° (BI)   -25° 
    C3'-exo -117° G12 C53 -118° C1'-exo    
 76°   -87° (BI)             -51° (BI)   73° 
    C2'-endo -103° G13 C52 -132° O1'-endo    
 0°   -69° (BI)             -33° (BI)   32° 
    -Pucker -96° C14 G51 -111° C2'-endo    
 26°   -150° (BI)             -72° (BI)   60° 
    C2'-endo -129° G15 C50 -124° C1'-exo    
 14°   -15° (BI)             -91° (BI)   47° 
    C1'-exo -109° T16 A49 -138° O1'-endo    
 55°   47° (BII)             -68° (BI)   -64° 
    O1'-endo -141° G17 C48 -117° C2'-endo    
 -44°   -45° (BI)             -69° (BI)   62° 
    C3'-exo -124° G18 C47 -120° C2'-endo    
 44°   -72° (BI)             -52° (BI)   -161° 
    C2'-endo -94° G19 C46 -154° O1'-endo    
 63°   -66° (BI)             61° (BII)   43° 
    C1'-exo -116° C20 G45 -100° C2'-endo    
 41°   46° (BII)             -62° (BI)   -72° 
    C1'-exo -121° G21 C44 -106° C3'-exo    
 -51°   -101° (BI)             -60° (BI)   57° 
    C3'-exo -85° T22 A43 -137° C1'-exo    


Groove width

Plot of minor groove width:   PDF,   GIF
Plot of major groove width:   PDF,   GIF
(See Help for further explanations.)

Further information

Full output from CURVES  (helical parameters with respect to global and local axes)

Full output from FREEHELIX  (helical parameters with respect to local axis, angles between normal vectors)

Chirality of ribose and phosphate atoms
Check the naming of phosphate and ribose substituents. Recommended for phosphate oxygens and for ribose hydrogens in NMR structures.


Go to    [JenaLib Home]    [Helix Analysis Home]    [Image Library Entry]    [Sequence, Chains, Units]    [Bending Analysis Entry]    [Bending Classification]   

Perl script:    helixparameter.pl  (15 Sep 2016)
Author:    Peter Slickers  (slickers@leibniz-fli.de),  IMB Jena,  Germany