Mass Spectrometry-Based Protein Identification Service

The identification and analysis of single proteins or protein mixtures via mass spectrometry, as well as the analysis of individual protein sequences, are critical tasks in biological research. Techniques include determining protein molecular weights, sequencing protein N- and C-termini, analyzing protein sequences, and identifying post-translational modification sites.

 

MtoZ Biolabs utilizes Thermo's latest Orbitrap Fusion Lumos mass spectrometer in conjunction with Nano-LC technology. This equipment allows for the precise and efficient identification of proteins from various samples such as protein extracts, SDS-PAGE bands, 2D gel spots, pull-down, and Co-IP assays.

 

Services at MtoZ Biolabs

1. Mass Spectrometry Analysis for Purified Protein

2. Mass Spectrometry of Proteins from Gel Spots and Strips, Including those with Silver, Coomassie Brilliant Blue, Fluorescence, and Zn/Cu2+ Staining

3. Analysis and Identification of Proteins in Simple Mixtures after Pull-Down, IP, and Co-IP by Mass Spectrometry

4. Analysis and Identification of Unknown Proteins in Complex Samples, Ensuring Detection even at Very Low Concentrations

 

We guarantee a 100% identification rate for single proteins and simple protein mixtures, with no charge if identification is unsuccessful.

 

Analysis Workflow

1. Sample Preprocessing

Protein samples are first reduced with dithiothreitol (DTT) and alkylated with iodoacetamide (IAA). Trypsin digestion follows, typically cleaving at lysine and arginine residues. The samples are then lyophilized to obtain peptide fragments.

 

2. Machine Analysis

The samples are redissolved in the mobile phase A of NanoLC and analyzed using the NanoLC-MS/MS system.

 

3. Database Search

For each sample, the corresponding species’ proteome database is downloaded from UniProt. Tools such as MaxQuant, Proteome Discoverer, and Peaks are used to match the mass spectrometry data with database entries, identifying proteins by comparing the masses of primary and secondary peptide fragments.

 

If a complete proteome database for the sample's species is not available, databases from closely related species or model organisms are used for analysis.

 

4. Issuing a Report

The final report includes detailed descriptions of sample preprocessing, LC-MS settings, and lists of identified proteins and peptides. Raw mass spectrometry data is made available via cloud storage.

 

You only need to collect your samples and provide them to us, and we will complete all subsequent steps. MtoZ Biolabs' mass spectrometry-based protein mass spectrometry identification/analysis service includes: sample preprocessing - protein reduction alkylation followed by digestion with highly specific proteases to obtain peptide fragments; machine analysis - separation of peptides through nano-flow chromatography combined with high-resolution mass spectrometry, collecting peptide mass spectrometry data at the highest sensitivity; database search - analyzing thousands of mass spectra (using the Uniprot database, updating the database monthly to ensure access to the latest data), thus achieving protein mass spectrometry identification of the sample; finally issuing a sample report, all done by MtoZ Biolabs in a one-stop manner:

 

(1) Provides a sample containing one or more proteins, such as gel strips, gel tapes, solutions, solid samples, pull-down, or Co-IP samples.

(2) Based on the sample situation, selects the appropriate enzyme for protein digestion and then performs nanoLC-MS/MS analysis.

(3) Analyze the obtained data.

(4) Receive the report within 10-15 working days.

 

*If your sample contains detergents/solvents, please note on the sample submission form.

• • Gel and IP Sample Protein Identification Service

  By combining MALDI-TOF mass spectrometry system and LC-MS/MS mass spectrometry system, MtoZ Biolabs provides professional and accurate protein identification services for protein spots, strips, and IP samples, as well as CO-IP sample proteins. The identifiable samples include: protein strips separated by 1D-SDS PAGE, protein spots in 2DE PAGE, protein expression products, and immunoprecipitation (Co-IP) samples.

• • Peptide Mass Fingerprinting Analysis Service

  Peptide mass fingerprinting (PMF), also termed protein fingerprinting, is a high-throughput analytical technique developed in 1933 for protein identification. It involves the cleavage of an unknown target protein into smaller peptides by endopeptidases, followed by the precise measurement of these peptides' absolute mass using a mass spectrometer to generate a peptide peak list.

• • Protein Identification Service by Shotgun Proteomics

  Shotgun proteomics, also known as shotgun method, refers to the utilization of bottom-up proteomics techniques to study all proteins present in complex mixtures such as serum, urine, and cell lysates. It combines high-performance liquid chromatography (HPLC) and mass spectrometry (MS). The uniqueness of shotgun proteomics lies in its ability to identify and quantify multiple proteins while minimally separating them.

• • Membrane Protein Identification Service

  Membrane proteins, such as receptors and ion channels, serve as crucial regulators of cellular function. Membrane proteins constitute two-thirds of known druggable targets, highlighting their significance in the biopharmaceutical industry.

• • Protein Profiling Service

  Proteins serve as the primary functional components of cells. Investigating proteins allows for a deeper understanding of biological processes, disease onset, and drug mechanisms. Protein profiling analysis, also known as shotgun proteomics, systematically examines all protein expression, functions, and interactions within biological samples. The objective of protein profiling analysis is to identify as many proteins as possible within a sample.

• • Protein Characterization Service

  Proteins serve as the carriers of life substances and executors of biological functions, playing a crucial role in maintaining normal physiological activities of organisms. Protein characterization analysis involves the characterization of protein purity, molecular weight, structure, post-translational modifications, and interactions, among others.

• • Unknown Protein Identification Service

  Unknown protein identification refers to the process of identifying, studying, and annotating proteins that are not fully understood in terms of function and structure. This process mainly includes protein molecular weight determination, amino acid sequence determination, structure prediction, functional analysis, and interaction network analysis. Mass spectrometry technology is an important method for identifying unknown proteins.

• • Protein Identification Service by Tandem Mass Spectrometry

  Protein tandem mass spectrometry (MS/MS) is an efficient, precise, and sensitive method for qualitative and quantitative identification of proteins based on mass spectrometry technology. It is widely used in proteomics research, biopharmaceutical quality control, disease biomarker discovery, and other fields. By analyzing the peptide fragments (products of protein digestion) using mass spectrometry, this technique identifies target proteins, including unknown ones.

• • MS-Based Protein Interaction Identification Service

  Interacting protein mass spectrometry identification is a method utilizing mass spectrometry technology to study protein-protein interactions. It separates target protein complexes through methods such as immunoprecipitation, affinity purification, etc. Then, it employs protein enzymatic digestion to generate peptide fragments, followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis of these peptides.