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 RESPONSE ELEMENT OF THE ORPHAN NUCLEAR RECEPTOR REV-ERB BETA
PDB code 1BN9   (PDB summary)
NDB code 1BN9 (NDB atlas)
Duplex length 15 base pairs

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' T1 A2 G3 A4 A5 T6 G7 T8 A9 G10 G11 T12 C13 A14 G15 3'
Strand 2    3' A16 T17 C18 T19 T20 A21 C22 A23 T24 C25 C26 A27 G28 T29 C30 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      

T1 A16            
    2.7 -0.1 -0.6 30° 10° -1°
A2 T17            
    3.0 0.1 -0.1 32° -4°
G3 C18            
    3.5 1.0 -0.5 36°
A4 T19            
    3.2 -0.8 0.5 40° -2° -2°
A5 T20            
    3.2 -0.1 -0.7 28° -4°
T6 A21            
    3.0 0.3 0.9 44° -2° -4°
G7 C22            
    3.3 -0.2 -0.4 30° -0°
T8 A23            
    3.0 -0.0 -0.2 33° -2°
A9 T24            
    3.4 0.9 -0.1 32° -7° -4°
G10 C25            
    4.2 0.0 -0.3 38°
G11 C26            
    3.7 -0.6 -0.2 36°
T12 A27            
    3.1 0.6 -0.1 31°
C13 G28            
    3.0 -0.9 0.7 39°
A14 T29            
    3.0 1.2 -0.4 31° -11° -3°
G15 C30            


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 -131° T1 A16 -106° C1'-exo    
 48°   -80° (BI)             -76° (BI)   54° 
    C1'-exo -112° A2 T17 -111° C2'-endo    
 50°   -75° (BI)             -65° (BI)   53° 
    C2'-endo -107° G3 C18 -119° C2'-endo    
 52°   -69° (BI)             -45° (BI)   58° 
    C2'-endo -116° A4 T19 -105° C2'-endo    
 55°   -25° (BI)             -68° (BI)   55° 
    C3'-exo -109° A5 T20 -122° C1'-exo    
 54°   -76° (BI)             -79° (BI)   56° 
    C2'-endo -113° T6 A21 -103° C3'-exo    
 55°   -47° (BI)             -27° (BI)   55° 
    C3'-exo -102° G7 C22 -114° C2'-endo    
 53°   -75° (BI)             -70° (BI)   45° 
    C1'-exo -113° T8 A23 -103° C2'-endo    
 54°   -71° (BI)             -75° (BI)   55° 
    C1'-exo -114° A9 T24 -112° C2'-endo    
 61°   -77° (BI)             -52° (BI)   60° 
    C2'-endo -119° G10 C25 -135° C2'-endo    
 58°   -47° (BI)             -49° (BI)   62° 
    C2'-endo -127° G11 C26 -122° C2'-endo    
 50°   -64° (BI)             -63° (BI)   51° 
    C2'-endo -113° T12 A27 -104° C2'-endo    
 52°   -77° (BI)             -51° (BI)   48° 
    C2'-endo -108° C13 G28 -97° C2'-endo    
 56°   -16° (BI)             -75° (BI)   55° 
    C3'-exo -105° A14 T29 -113° C2'-endo    
 57°   -82° (BI)             -50° (BI)   0° 
    C1'-exo -122° G15 C30 -130° C2'-endo    


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