C-terminal Sequencing Analysis Service

The C-terminal sequence is an important structural and functional part of proteins and peptides, and plays a role in the biological function of proteins. In the analysis process of recombinant protein expression and purification products, especially the development and process establishment of recombinant protein products, the C-terminal sequence of the protein needs to be identified and analyzed to study the type of degradation products of protein drugs and the specificity of enzyme cleavage . Our protein C-terminal sequencing technology service can provide C-terminal sequencing analysis methods for biopharmaceutical proteins or other biological reagents such as MALDI-ISD for Top-down protein C-terminal sequencing and carboxypeptidase hydrolysis.

Creative Proteomics is a reliable biopharmaceutical partner with professional proteomics research resources. We use first-class experimental platform and mature technical methods to provide you with high-quality one-stop service. The quality control of the biopharmaceutical industry requires information on the identification and structural analysis of the C-terminal sequence of protein and peptide drug molecules. In particular, the ICH Q6B guidelines require the C-terminal sequence information of protein (peptide) drugs. To this end, we will provide you with comprehensive N-terminal sequencing technology services. We will provide you with comprehensive and GLP / cGMP-compliant N-terminal sequencing analysis service around the ICH guidelines (especially ICH Q6B) and the US FDA issues 'Points to Consider' document.

We Can Provide but Not Limited to:

  • Analysis of amino acid release
  • Advanced structural analysis of proteins
  • C-terminal sequence analysis
  • Target peptide fragmentation poor quality analysis
  • C-terminal modification site type analysis
  • Protein molecular analysis

Technology Platform of C-terminal Sequencing Analysis Service:

Creative Proteomics uses MALDI-ISD to perform Top-down protein sequencing, mass spectrometry analysis technology, carboxypeptidase kinetics technology, C-terminal amino acid release technology and other technologies to effectively and accurately analyze the protein C-terminal sequence.

We provide the following analysis methods:

1) MALDI Top-Down Sequencing.
MALDI-ISD is used to break the inter-residue bond of the target peptide, which mainly cleaves the N-Cα bond of the main chain of the target peptide, so that it is fragmented in the mass spectrometer, and then is cleaved by the inter-residue bond by analysis. The mass difference between the generated series of consecutive fragment ions is used to identify the C-terminal sequence of the target peptide. The specific workflow is as follows.

MALDI Top-Down Sequencing

2) Carboxypeptidase hydrolysis method
First, carry out the kinetic experiment of carboxypeptidase to determine the appropriate enzyme concentration and reaction time, so that the released amino acids are mainly C-terminal amino acids. According to the relationship between the amount of released amino acids (moles) and the reaction time, the peptide chain can be identified C-terminal amino acid sequence. The specific workflow is as follows.

Carboxypeptidase hydrolysis method

Advantages of C-terminal Sequencing Analysis Service:

  • Short time-consuming: MALDI-ISD for Top-down protein sequencing method does not require proteinase digestion by protease,it can identify the C-terminal sequence of the protein within 1 minute and confirm the type of C-terminal modification, which greatly shortens the time for sample identification and analysis.
  • High sensitivity: Using mass spectrometry analysis methods can get high sensitivity during the analysis of C-terminal sequence.
  • High-throughput: In this service, the C-terminal sequence of the protein can be combined by MALDI-ISD Top-down protein C-terminal sequencing and carboxypeptidase hydrolysis method, these two methods can complement each other to obtain complete C-terminal sequence analysis information.
  • Rapid turnaround time: 5-7 days to provide detailed technical reports.
  • Customized service: We can customize professional solutions for you according to your research plan needs. You can select or suggest the required items for analysis.

Creative Proteomics's professional researchers can provide customers with complete C-terminal sequence analysis information of proteins to speed up your research on advanced protein structure, C-terminal sequence analysis and modification types. We will provide you with detailed experimental design and final C-terminal sequence information analysis report and other data reports.


  • Asakawa D. Principles of hydrogen radical mediated peptide/protein fragmentation during matrix-assisted laser desorption/ionization mass spectrometry. Mass Spectrom Rev, 2016.
  • Zhang X, Zhang L, Li J. Peptide-modified nanochannel system for carboxypeptidase B activity detection. Anal Chim Acta, 2019.

*For Research Use Only. Not for use in the treatment or diagnosis of disease.

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