The sequence analysis of samples such as proteins, antibodies, and polypeptides based on mass spectrometry is the analysis of the amino acid sequence of the samples. Mass spectrometry sequencing refers to the determination of the amino acid sequence of the primary structure of a sample based on mass spectrometry. Amino acids are organic compounds that contain amine (-NH2) and carboxyl (-COOH) functional groups and side chains (R groups) unique to each amino acid. Peptides are short chains of two to fifty amino acids linked by peptide bonds. Polypeptides are longer, contiguous, unbranched chains of up to about fifty amino acids. Polypeptides/peptide chains containing more than fifty amino acids are called proteins. A protein is composed of one or more polypeptides that typically bind a ligand (such as coenzymes and cofactors), another protein, other macromolecules (such as DNA or RNA), or more complex macromolecular assemblies. Antibodies (Abs), also known as immunoglobulins (Ig), are large Y-shaped proteins mainly produced by plasma cells and used by the immune system to neutralize pathogens such as pathogenic bacteria and viruses.
Our Mass Spectrometry sequencing Services
Mass Spectrometry-based Protein Sequencing
Mass Spectrometry-based Antibody Sequencing
Mass Spectrometry-based Peptide Sequencing
The advantages of mass spectrometry sequencing over Edman degradation are that mass spectrometry is more sensitive, allows faster cleavage of peptides, and can identifyend-blocked or modified protein samples. Creative Proteomics provides mass spectrometry-based sequence analysis services using high-resolution mass spectrometry technology platform, which can achieve 100% coverage of target protein sequences.
The sequence analysis process of protein samples will generally only use Trypsin for protein digestion, and the coverage of identified peptides is about 60%. In order to obtain the full sequence information of the target proteins, we use six proteases (Trypsin, Chymotrypsin, Asp-N, Glu-C, Lys-C and Lys-N) commonly used in protein sequence analysis to perform enzymatic cleavage and mass spectrometry on the target proteins to complete the determination of 100% of the protein sequence.
Creative Proteomics uses Obitrap Fusion Lumos mass spectrometer for sequence analysis of protein samples. The Obitrap Fusion Lumos mass spectrometer is the highest resolution and sensitive mass spectrometer available, ensuring the sensitivity of fragmented fragment identification of low-abundance peptides At the same time, we adopt the mode of combining HCD and ETD in the process of peptide fragmentation to ensure the integrity of peptide fragmentation fragments. We can realize N-terminal, C-terminal sequence analysis of protein samples, and full-length protein sequence analysis. For samples with unknown theoretical sequences, sequence analysis can be performed by de novo sequencing.
Workflow of mass spectrometry sequencing
The following mass spectrometry-based sequence analysis services are available:
Full protein sequence determination