Post-translational modifications (PTMs) controlling various biological functions are a key aspect of protein diversity. To achieve a qualitative and quantitative analysis of various PTM, we mainly use mass spectrometry (MS)-based proteomics methods. MS-based proteomics is the method of choice for studying proteins and their PTMs. This sensitive technique allows not only the identification of previously unknown modification patterns but also the simultaneous determination of multiple isoforms of one protein with different modifications.
MS-based proteomics for PTM analysis
MS is currently the gold standard and the most informative technique for protein analysis. Similar to conventional protein identification, MS-based methods for PTM analysis include top-down, bottom-up, and middle-down proteomics. Bottom-up proteomics requires enzymatic digestion of proteins into peptide fragments prior to MS analysis, while in the case of top-down proteomics, intact proteins are directly introduced and evaluated by MS/MS analysis. Middle-down proteomics is an in-between case, working with large polypeptides produced by restricted proteolytic digestion. As the most commonly used MS method, bottom-up MS-based proteomics is useful in discovering novel PTM and specific modification sites, while top-down and middle-down MS-based proteomics provides the sequence context needed to identify co-occurring modifications.
| MS-based proteomics methods |
|---|
| Terms | Top-down MS-based proteomics | Bottom-up MS-based proteomics | Middle-down MS-based proteomics |
|---|
| Protein digestion | No | Yes | Yes |
| PTM detection | Yes | Yes | Yes |
| Analyzed sample forms | Full-length proteins | Peptide fragments | Peptide fragments |
| Detection efficiency | Relative low | Significantly high | High |
| Applications | Suitable for the characterization of small proteins.
Identify sequence variants and PTM combinations. | Well-developed for protein quantitation.
Suitable for peptide-specific modification analysis and determination of peptide modification status. | Suitable for the analysis of polypeptides and combinatorial PTMs. |
The service offering at Creative Proteomics
To help clients achieve reliable and comprehensive PTM analysis, Creative Proteomics offers different MS-based strategies, including bottom-up, middle-down, and top-down proteomics. Based on our customers' needs, we provide the best analytical strategies and solutions to facilitate biomarker discovery, disease research, protein biopharmaceutical characterization, etc.
Applications of our service
- Biomarker discovery and research.
- Histone PTM analysis and identification.
- Disease mechanism research.
- Protein biopharmaceutical characterization, such as monoclonal antibody characterization.
It is worth noting that each MS strategy has its advantages and disadvantages. To achieve a comprehensive protein PTM analysis, these approaches can be combined. We have experienced MS-based proteomics scientists and technicians and are dedicated to providing our customers with quality PTM characterization services. Feel free to contact us for more information about our services. Our customer service representatives are available 24 hours a day from Monday to Sunday.
References
- Virág, Dávid, et al. "Current trends in the analysis of post-translational modifications." Chromatographia 83.1 (2020): 1-10.
- Pandeswari, P. B., & Sabareesh, V. (2019). Middle-down approach: a choice to sequence and characterize proteins/proteomes by mass spectrometry. RSC advances, 9(1), 313-344.
Our products and services are for research use only.
