The use of mass spectrometry for the characterization of individual or complex protein samples continues to be one of the fastest growing fields in the life science market.
Bottom-up proteomics is the traditional approach to address these questions. Optimization of each the individual steps (e.g. sample prep, digestion and instrument performance) is critical to the overall success of the entire experiment.
To address issues that may arise in your experimental design, Promega has developed unique tools and complementary webinars to help you along the way.
The novel mass spectrometry compatible surfactant sulfonate-(sodium 3-((1-(furan-2-yl)undecyloxy) carbonylamino)-propane-1-sulfonate (i.e.ProteaseMAX) facilitates both in-gel and in-solution digestion applications by reducing the time required, enabling protein solubilization/denaturation and increasing peptide/protein identifications.
A new application was highlighted in a recent publication (1) which utilized ProteaseMAX to lyse cells prior to trypsin digestion and subsequent mass spec analysis. The composition of the buffer determines the overall efficiency of cell lysis, dissociation of protein complexes, protein solubility and ease of removal prior to LC/MS-MS analysis.
When compared to lysis buffers containing either urea or SDC, ProteaseMAX provided the optimal number of identified peptides/proteins.
In addition it can be easily removed from the lysate by acidic precipitation.
Pirmoradian, M. et al. (2013). Rapid and deep human proteome analysis by single-dimension shotgun proteomics. Mol. Cell. Prot.12, 3330–8.
Efficient proteolysis is a major requirement for protein mass spectrometry analysis. Incomplete digestion has multiple ramifications including decreased number of identified proteins, compromised analytical reproducibility and protein quantitation, etc. Trypsin is one of the most robust proteases and is characterized by efficient proteolysis. Typical trypsin reactions do not digest proteins to completion, missing 15–30% of cleavage sites. Incomplete digestion affects protein identification, reproducibility of mass spectrometry analysis and accuracy of protein quantitation. Supplementing Trypsin with Lys-C compensates for the majority of missed cleavages. Continue reading “Enhanced Protein Mass Spectrometry Analysis with Trypsin/Lys-C Mix”