How to apply protein's omics to his own topic?

How to apply protein's omics to his own topic?

Identification of isolated protein is an important part of protein Formation research. Traditional protein identification techniques, such as protein Microsequencing and amino acid composition analysis, can no longer meet the requirements of Qualcomm quantity and high efficiency. Biological mass spectrometry is another supporting technology of genomics in protein.

There are two main soft ionization techniques in biological mass spectrometry, namely matrix-assisted laser desorption ionization (MALDl) and electrospray ionization (ESl). MALDI volatilizes from the matrix crystal and ionizes the sample under the excitation of laser pulse. ESI ionizes the analyte in the solution phase, so it is suitable to be used in combination with liquid phase separation methods such as liquid chromatography and capillary electrophoresis. MALDI is suitable for the analysis of simple peptide mixtures, while LC-MS is suitable for the analysis of complex samples.

The appearance of soft ionization technology expands the application space of mass spectrometry, and the improvement of mass analyzer also promotes the development of mass spectrometry technology. There are four kinds of mass analyzers used in biological mass spectrometry: ion trap (IT), time of flight (TOF), quadrupole and Fourier transform ion cyclotron resonance (FTICR). Their structures and properties are different, and each has its own advantages and disadvantages. They can be used alone or combined with each other to form a more powerful tool.

Ion trap mass spectrometry has high sensitivity, stable performance and multi-stage mass spectrometry ability, so it is widely used in protein omics research, but it has the disadvantage of low quality accuracy. Similar to ion trap, Fourier transform ion cyclotron resonance (FTICR) mass spectrometry is an instrument that can "capture" ions, but its cavity is in a high vacuum and high magnetic field environment, with high sensitivity, wide dynamic range, high resolution and mass accuracy (the mass accuracy can be easily less than 65,438+0 mg/L), which makes it possible to determine the mass of hundreds of complete protein molecules in one analysis. An important function of FTICR-MS is multi-element tandem mass spectrometry. Different from the usual tandem mass spectrometry, FTICR-MS can select several parent ions for dissociation at the same time, which will undoubtedly greatly increase the flux of protein identification. However, its disadvantages are obvious, such as complicated operation, low efficiency of peptide cleavage and high price, which limit its wide application in protein omics. MALDI is usually combined with TOF mass spectrometry to analyze the precise mass of peptide fragments, while ESI is usually combined with ion trap or quadrupole mass spectrometry to obtain the fragment information of peptide fragments through collision-induced dissociation (CID).