Peptide Sequencing: Advanced Techniques for Amino Acid Arrangement

Peptides are formed by the connection of amino acids through peptide bonds, and peptide sequence detection refers to the determination of the specific order of amino acids in peptides or proteins. This information is crucial for understanding the function, structure, and interaction of peptides with other molecules.

 

Main Technologies

1. Edman Degradation

This is a classic sequence determination method that achieves its goal by continuously removing amino acid residues from the N-terminal of the peptide. This method is especially useful for short peptides, but the length is limited, usually not exceeding 50-60 amino acids.

 

2. Mass Spectrometry

Mass spectrometry has become the preferred technology for modern peptide sequence detection. It works by cutting the peptide into small fragments and then measuring the mass and sequence of these fragments. High-resolution mass spectrometers can quickly and accurately identify the sequences of long-chain peptides and proteins.

 

3. DNA Sequencing

Considering that proteins are encoded by genes, directly determining the DNA sequence of the corresponding gene is also a method to obtain peptide sequences.

 

Application

1. Structural Biology

Determining the sequence of a peptide is the first step in predicting its three-dimensional structure.

 

2. Functional Biology

By comparing with peptides or proteins of known function, the function of unknown peptides can be inferred.

 

3. Drug Discovery

Many drug targets are proteins. Determining their amino acid sequences can aid in the design of small molecules that bind to them.

 

4. Disease Diagnosis and Research

Certain diseases are related to mutations in proteins or peptides. Determining these mutations can aid in the diagnosis and treatment of the disease.

 

5. Evolutionary Biology

By comparing the sequences of similar peptides in different species, their evolutionary relationships can be inferred.