Peptide Sample Analysis in Peptide Identification Technology

Identification and analysis of the biological world is a key step in deciphering any form of life science problem. Among these analyses, peptide identification technology, with its superior precision and profound complexity, occupies an important position in scientific research. Peptides are usually products of protein degradation, composed of different arrangements and conformations of several to several hundred amino acids, and can participate in or regulate many biological processes widely.

 

Basic Strategy of Peptide Identification

Identification of peptide samples mainly consists of two steps: Firstly, generate peptide samples through protein hydrolysis; then, identify the peptide especially the amino acid sequence, using mass spectrometry. The basic steps involved in mass spectrometry include ionization, protonation, flight, detection, etc.

 

Continuous technological innovation makes today's peptide identification work effective. At present, the most widely used and successful peptide identification technology is Liquid Chromatography-Mass Spectrometry (LC-MS/MS), which segments peptides and arranges them for sequencing within a certain period of time through liquid mass coupling technology.

 

Characteristics of Peptide Samples

We can analyze the protein structure of peptides through methods such as X-ray crystallography, NMR and Cryo-EM. The functions or biologically active properties of peptides include enzyme catalysis, antibody recognition, hormone signal transduction, etc. We can study them through biochemical and molecular biological methods, such as enzyme activity detection, affinity experiments, signal pathway detection, etc.

 

Since peptides are functional, there must be interactions between them. These interactions may restrain or affect the function of peptides. For the study of peptide interactions, we can track and verify through techniques such as Enzyme-linked Immunosorbent Assay (ELISA), Biochromatography, Co-immunoprecipitation (Co-IP), etc., to better understand the mechanism of peptide action.

 

Information Covered by Peptide Identification

In addition to revealing the composition of peptide samples, peptide identification can reveal multiple characteristics of peptide samples through advanced data analysis means. For example, hydrophobicity, acidity and alkalinity, compact structure, conformation, etc. of peptides.

 

Additionally, by identifying peptide modification situations, such as phosphorylation, acetylation, ubiquitination, etc., we can further understand the functions of peptides in various biological processes such as signal transduction, gene expression regulation, etc.

 

Optimization of peptide identification

Here are some issues we need to face, such as sample complexity, detection sensitivity, and difficulty of data analysis.

 

For sample complexity, we can reduce complexity through separation technology, such as high performance liquid chromatography, electrophoresis; for detection sensitivity, we can optimize sample quality through preprocessing steps, such as sample purification and concentration; the difficulty of data analysis is well solved by various mass spectrometry analysis software, such as Mascot, Sequest, MaxQuant, etc.