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Analyzing and Building Nucleic Acid Structures with 3DNA
Published on: April 26, 2013
Characterization of alpha helices interacting with nucleic acids.
R Sreekanth1, Vasantha Pattabhi, S S Rajan
1Centre of Advanced Study in Crystallography and Biophysics, University of Madras, Chennai, India.
Computational Biology and Chemistry
|August 1, 2008
Summary
Most alpha helices interacting with nucleic acids show structural distortions, with many exhibiting bends. These findings enhance understanding of protein-nucleic acid complex geometry.
Area of Science:
- Structural biology
- Biochemistry
- Genetics
Background:
- Protein-nucleic acid interactions are fundamental to genetic processes.
- Understanding the structural basis of these interactions is crucial.
Purpose of the Study:
- To survey the geometry of alpha helices involved in nucleic acid binding.
- To characterize structural variations induced by nucleic acid interactions.
Main Methods:
- Analysis of 161 alpha helices from 70 non-redundant protein chains using X-ray crystallography.
- Utilized the RADIL program and a custom algorithm to assess helical geometry.
Main Results:
- Approximately 70% of analyzed alpha helices displayed distortions (bend, terminal, or complete).
- Nearly one-third of helices had bends, predominantly between 5-15 degrees.
- Bent helices often approached nucleic acid helices perpendicularly.
Conclusions:
- Alpha helices in protein-nucleic acid complexes exhibit significant structural variability.
- The RADIL program effectively characterizes nucleic acid-induced structural changes in alpha helices.
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