What Is Peptide Mass Spectrometry Identification

Peptides are a class of compounds whose molecular structure lies between amino acids and proteins, composed of 20 natural amino acids in different compositions and arrangements, from dipeptides to complex linear or cyclic structures of polypeptides. We refer to peptides composed of 2-10 amino acids as oligopeptides, those composed of 11-50 amino acids as polypeptides, and those composed of more than 50 amino acids as proteins. There is no strict distinction between polypeptides and proteins, only the length of the peptide chain differs.

 

As an important bioactive substance, polypeptides play an important role in life activities and are widely used in the fields of medicine, health food, cosmetics, etc. Therefore, the identification of polypeptides is of great significance. There are various methods for identifying polypeptides, among which the most common is peptide mass spectrometry.

 

Peptide mass spectrometry identification is the use of mass spectrometry to analyze and identify peptides, mainly for qualitative identification. Mass spectrometry is based on the principle of measuring the mass-to-charge ratio (m/z). The peptide sample is first ionized into charged particles, then separated in an electromagnetic field according to the mass-to-charge ratio, and finally the ion intensity of different mass-to-charge ratios is detected and recorded by a detector. By analyzing these data, the molecular weight, amino acid sequence, and post-translational modifications of the peptide can be inferred. 

 

Analysis Workflow

1. Sample Preparation

This is the first step in peptide mass spectrometry identification, which usually includes protein digestion and enrichment. Proteins are digested into peptide fragments by proteases and the target peptides are separated by liquid chromatography and gel electrophoresis separation and enrichment techniques.

 

2. Mass Spectrometry Analysis

This is the key step in peptide mass spectrometry identification. The peptide fragments are ionized in the mass spectrometer and separated according to the mass-to-charge ratio in the magnetic field, eventually producing a mass spectrum. Based on the mass and fragmentation pattern of the peptide fragments in the mass spectrum, the sequence of the peptide can be inferred.

 

3. Data Interpretation

By comparing the experimentally obtained mass spectrometry data with known protein databases, the sequence information of the peptide fragments can be determined. Researchers can use bioinformatics tools and algorithms to analyze and interpret mass spectrometry data, thereby accurately identifying peptide sequences in proteins.

 

At present, peptide mass spectrometry identification has a wide range of application value in the fields of biology, medicine, etc. For example, it can be used in biological research: it can help researchers determine the sequence and structure of unknown proteins, thereby understanding the function and mechanism of action of proteins; it can be used in the field of drug development: it can help researchers identify drug targets and understand the mechanism of drug-protein interactions. In general, as a highly efficient and accurate protein analysis technique, peptide mass spectrometry identification plays an important role in promoting life science research and medical progress.

 

MtoZ Biolabs uses the latest Obitrap Fusion Lumos mass spectrometer from Thermo, combined with Nano-LC nano-scale chromatography technology, to provide high-resolution and high-sensitivity identification of peptides. You only need to provide the sample, we will provide you with a one-stop service of "sample processing-machine analysis-data analysis-project report", welcome your consultation.