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 THE T(-24) ADENOVIRUS MAJOR LATE PROMOTER TATA BOX VARIANT BOUND TO WILD-TYPE TBP (ARABIDOPSIS THALIANA TBP ISOFORM 2). TATA ELEMENT RECOGNITION BY THE TATA BOX-BINDING PROTEIN HAS BEEN CONSERVED THROUGHOUT EVOLUTION.
PDB code 1QN4   (PDB summary)
NDB code PD0154 (NDB atlas)
Duplex length 14 base pairs
Protein TBP, Transcription factor, DNA binding domain: TATA box binding protein

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' G201 C202 T203 A204 T205 A206 A207 A208 A209 T210 G211 G212 C213 A214 3'
Strand 2    3' C228 G227 A226 T225 A224 T223 T222 T221 T220 A219 C218 C217 G216 T215 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      

G201 C228            
    2.9 -0.3 -0.6 34° -13°
C202 G227            
    3.7 1.3 0.6 40° -18° -4°
T203 A226            
    3.7 -0.0 -1.0 32° 39° -5°
A204 T225            
    2.6 -0.8 -1.4 24°
T205 A224            
    3.4 0.2 1.3 31° -12°
A206 T223            
    2.9 0.4 0.3 27° 12° -5°
A207 T222            
    3.2 -0.2 0.1 27° -0°
A208 T221            
    2.9 0.4 0.2 31° -1° -1°
A209 T220            
    4.3 0.2 -1.5 28° 37° -0°
T210 A219            
    3.2 -0.5 0.1 36° -5°
G211 C218            
    3.2 0.5 -0.4 33° -7°
G212 C217            
    3.0 -0.0 -0.3 36° -7°
C213 G216            
    3.1 0.8 1.1 41° -10° -3°
A214 T215            


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 

    C3'-endo -176° G201 C228 -145° C2'-endo    
 59°   9° (BI)             -105° (BI)   52° 
    C2'-endo -115° C202 G227 -106° C2'-endo    
 52°   -69° (BI)             14° (BI)   55° 
    C3'-endo -131° T203 A226 -94° C2'-endo    
 62°   -88° (BI)             -71° (BI)   57° 
    C2'-endo -122° A204 T225 -119° C4'-exo    
 50°   -78° (BI)             -91° (BI)   58° 
    O1'-endo -123° T205 A224 -116° C3'-endo    
 52°   -62° (BI)             -72° (BI)   50° 
    C4'-exo -104° A206 T223 -107° C4'-exo    
 43°   -75° (BI)             -71° (BI)   58° 
    C3'-endo -106° A207 T222 -120° C4'-exo    
 51°   -73° (BI)             -88° (BI)   49° 
    C3'-endo -113° A208 T221 -124° C4'-exo    
 56°   -80° (BI)             -65° (BI)   55° 
    C3'-endo -117° A209 T220 -125° C1'-exo    
 58°   -66° (BI)             -74° (BI)   60° 
    C1'-exo -114° T210 A219 -152° C3'-endo    
 53°   -36° (BI)             -89° (BI)   48° 
    C2'-endo -110° G211 C218 -151° C4'-exo    
 53°   -90° (BI)             -16° (BI)   51° 
    C2'-endo -105° G212 C217 -102° C2'-endo    
 54°   -39° (BI)             -75° (BI)   -169° 
    C1'-exo -111° C213 G216 -99° C3'-exo    
 73°   -16° (BI)             78° (BII)   61° 
    C3'-exo -103° A214 T215 -101° 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