Basic Strong Cation Exchange Chromatography, BaSCX, a Highly Efficient Approach for C-Terminomic Studies Using...

Area of Science:

• Proteomics
• Biochemistry
• Chromatography

Background:

• Protein C-termini analysis is challenging with conventional methods.
• Mass spectrometry (MS)-based approaches have advanced C-terminomics.
• More efficient methods are needed for proteome-scale C-terminome discovery.

Purpose of the Study:

• To introduce the BaSCX (basic strong cation exchange) chromatography method for C-terminome studies.
• To establish a more efficient approach for identifying protein C-termini and their modifications.

Main Methods:

• Utilized carboxylic amidation, LysargiNase digestion, and optimized search parameters.
• Employed basic strong cation exchange chromatography (BaSCX).
• Analyzed protein C-termini from HeLa, 293T cells, mice, *C. elegans*, and tomatoes.

Main Results:

• Identified 2151 human protein C-termini, tripling the largest previously reported dataset.
• Achieved similar results across different organisms.
• Discovered novel C-terminal modifications, including methyl-esterified and α-amidated protein C-termini.

Conclusions:

• The BaSCX method is highly effective for large-scale C-terminome analysis.
• BaSCX enables the discovery of previously unknown C-terminal modifications.
• This technique holds significant potential for advancing C-terminomics research.