What Common Qualitative Methods are Used for Protein Identification?

Protein is an important functional molecule in biological systems, and its identification and qualification are crucial for understanding the function and mechanism of biological systems. Protein qualification refers to determining the existence and nature of proteins, which involves many common qualification methods. This article will introduce the commonly used qualification methods in the field of protein qualification, discuss the technical principles and applications of protein identification, and reveal the importance and diversity of protein qualification for readers.

 

Mass Spectrometry Analysis

1. Protein Identification

Through mass spectrometry analysis techniques, such as Liquid Chromatography-Mass Spectrometry (LC-MS), Capillary Electrophoresis-Mass Spectrometry (CE-MS), etc., the protein samples are separated and then analyzed by mass spectrometry to identify and qualify the proteins based on the mass spectra.

 

2. Protein Sequence Analysis

Through mass spectrometry analysis techniques, such as Tandem Mass Spectrometry (MS/MS), the protein samples are fragmented and analyzed to deduce the sequence information of the proteins.

 

Gel Electrophoresis Method

1. Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE)

The samples are separated by electrophoresis based on the molecular weight of the protein, and then the proteins are identified and qualified by staining or mass spectrometry analysis.

 

2. Western Blotting

The proteins separated by electrophoresis are transferred to a membrane, and then detected using a specific antibody, achieving the qualification of the target protein.

 

Immunoprecipitation Method

The target protein is precipitated from the mixed sample using a specific antibody, and then the protein is identified and qualified by staining, mass spectrometry analysis, etc.

 

Enzyme Activity Analysis Method

The protein is indirectly identified and qualified by measuring the enzyme activity, such as the conversion rate of the enzyme substrate or the formation of the product in the enzyme-catalyzed reaction.

 

Protein Interaction Analysis Method

Through protein interaction analysis techniques, such as yeast two-hybrid, co-immunoprecipitation, etc., the interaction relationship between the protein and other molecules is determined, thereby identifying and qualifying the target protein.

 

Genomics Method

By analyzing the gene expression profile, mutation spectrum, etc., related to the gene encoding the target protein, the existence and function of the protein are inferred.

 

Protein qualification and identification is an important part of proteomics research. Through a variety of qualification methods such as mass spectrometry analysis, gel electrophoresis, immunoprecipitation, enzyme activity analysis, protein interaction analysis, and genomics methods, we can accurately determine the existence and nature of proteins. These methods play an important role in biological drug research, life science research, and clinical diagnosis. By deeply understanding and applying these common qualification methods, we can better understand the function and regulation mechanism of proteins, and promote research and application in the field of biological drugs.