Construct Sequence Graph: Application of Protein Group Mass Spectrometry Analysis LC-MS/MS

Proteins are the most basic functional molecules in biological organisms and are of great significance for understanding the structure and function of organisms. However, the complexity of proteins makes their research challenging. To solve this problem, scientists have developed a technology called proteome mass spectrometry analysis, where Liquid Chromatography-Mass Spectrometry/Mass Spectrometry (LC-MS/MS) is one of the most commonly used methods.

 

Proteome Mass Spectrometry Analysis LC-MS/MS is a technology that combines Liquid Chromatography (LC) and Mass Spectrometry (MS) used to identify and quantify proteins in complex samples. The principle of LC-MS/MS technology is to separate the proteins in the sample through liquid chromatography and send them one by one into the mass spectrometer for mass spectrometry analysis. The mass spectrometer will break down the protein molecules into peptides and identify the protein sequence and modifications through the analysis of the mass spectrum.

 

Methods of Constructing Sequence Spectra

Constructing a sequence spectrum is one of the key steps in proteome mass spectrometry analysis LC-MS/MS. Below are two commonly used methods for constructing sequence spectra.

 

1. Database Search Method

The database search method is a commonly used method for constructing sequence spectra. First, the mass spectrum obtained by the mass spectrometer is compared with a known protein sequence database. During the comparison process, the mass, fragmentation mode, and modification information of the peptides are considered. Through comparison, protein sequences that match the mass spectrum can be found, thus determining the protein identification results.

 

2. Spectrum Library Search Method

The spectrum library search method is another commonly used method for constructing sequence spectra. In this method, proteins in a known protein sequence database are digested in vitro to produce a series of peptides. The mass spectra of these peptides are then stored in a spectrum library. During actual analysis, the mass spectrum obtained by the mass spectrometer is compared with the mass spectra in the spectrum library, thus finding the matching peptides and protein sequences.

 

Significance of Constructing Sequence Spectra

The construction of sequence spectra has important significance in proteome mass spectrometry analysis. First, by constructing sequence spectra, the sequence and modification information of proteins can be determined, thereby understanding the function and structure of proteins. Secondly, sequence spectra can be used to identify unknown proteins, helping scientists discover new biomarkers or drug targets. In addition, sequence spectra can also be used for quantitative analysis, comparing the expression levels of proteins in different samples.

 

Proteome mass spectrometry analysis LC-MS/MS can help us study the structure and function of proteins. Constructing sequence spectra is one of the key steps in proteome mass spectrometry analysis, which can be achieved through the database search method and spectrum library search method. The significance of constructing sequence spectra lies in determining the sequence and modification information of proteins, identifying unknown proteins, and carrying out quantitative analysis.