Exploring Circular Dichroism for Secondary Structure Analysis in Biomolecules

Studying the structure and function of biological macromolecules is of major significance for drug development and biomedical fields. Among them, Circular Dichroism (CD) secondary structure analysis, as a very effective method, is widely used in the research and analysis of biological macromolecules.

 

Circular Dichroism is a technology that studies molecular structure by measuring the absorption difference of molecules to left and right circularly polarized light. It utilizes the chiral properties of molecules, that is, the non-symmetry of molecules leads to the absorption difference of circularly polarized light. By measuring the absorption of samples to circularly polarized light of different wavelengths, the CD spectrum of the sample can be obtained.

 

Technical Principles of Circular Dichroism

The measurement of Circular Dichroism is based on two key technical principles: polarization rotation and dispersion.

 

1. Polarization Rotation

Polarization rotation refers to the rotation of light when it passes through chiral molecules, due to the non-symmetry of molecules. The direction and angle of rotation of left and right circular light are closely related to the structure of the molecule. By measuring the absorption difference of the sample to left and right circularly polarized light, information about the molecular structure can be obtained.

 

2. Dispersion

Dispersion refers to the phenomenon that light of different wavelengths has different propagation speeds in a medium. Circular Dichroism uses the phenomenon of dispersion. By measuring the absorption of samples to circularly polarized light of different wavelengths, the CD spectrum of the sample can be obtained.

 

Application of Circular Dichroism in the Research of Biological Macromolecules

Circular Dichroism has a wide range of applications in the research of biological macromolecules, mainly including the secondary structure analysis of proteins and nucleic acids, drug screening and structural optimization.

 

1. Protein Secondary Structure Analysis

The secondary structure of proteins refers to the spatial arrangement of amino acid residues in proteins. Circular Dichroism can obtain information about the secondary structure of proteins by measuring the absorption difference of proteins to circularly polarized light. By analyzing the CD spectrum, the content and spatial arrangement of α-helices, β-folds and other secondary structures in proteins can be determined.

 

2. Nucleic Acid Secondary Structure Analysis

The secondary structure of nucleic acids refers to the spatial arrangement of nucleic acid chains. Circular Dichroism can obtain information about the secondary structure of nucleic acids by measuring the absorption difference of nucleic acids to circularly polarized light. By analyzing the CD spectrum, the content and spatial arrangement of double-strand and single-strand structures in nucleic acids can be determined.

 

3. Drug Screening and Structural Optimization

Circular Dichroism can be used for drug screening and structural optimization. By measuring the absorption difference of drug molecules to circularly polarized light, the interaction between drug molecules and target proteins can be evaluated. This is of great significance for drug development and optimization, helping scientists to select drug molecules with good interactions.

 

The secondary structure analysis of Circular Dichroism, as a very effective means, plays an important role in the research of biological macromolecules. It can provide information about the secondary structure of proteins and nucleic acids, helping scientists to understand the structure and function of biological macromolecules. In addition, Circular Dichroism can also be used for drug screening and structural optimization, providing important references for drug development. With the continuous development of technology, the application prospects of Circular Dichroism in the research of biological macromolecules will be even broader.