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A Fast and Quantitative Method for Post-translational Modification and Variant Enabled Mapping of Peptides to Genomes
Published on: May 22, 2018
Amino acid sequence and post-translational modification of human interleukin 2
Summary
Human interleukin 2 exhibits molecular heterogeneity due to glycosylation variations, but these do not impact its activity. Researchers determined the complete primary sequence and disulfide bridge location for interleukin 2.
Area of Science:
- Immunology
- Protein Chemistry
- Molecular Biology
Background:
- Human interleukin 2 (IL-2) is a critical cytokine involved in immune responses.
- Molecular heterogeneity of IL-2 has been observed, suggesting post-translational modifications.
- Understanding IL-2 structure and function is crucial for immunology and therapeutic development.
Purpose of the Study:
- To investigate the molecular heterogeneity of human interleukin 2.
- To identify the specific modifications causing IL-2 heterogeneity.
- To determine the complete primary sequence and disulfide bridge of IL-2.
Main Methods:
- Selective immunoaffinity chromatography
- Chromatofocusing
- Peptide mapping
- Protein sequencing
Main Results:
- Human IL-2 was separated into multiple molecular forms.
- Heterogeneity was primarily attributed to glycosylation variations at threonine position 3.
- Different molecular forms showed nearly identical specific activities in proliferation assays.
- The complete primary sequence and the intramolecular disulfide bridge location were determined.
Conclusions:
- Glycosylation variations of human IL-2 do not significantly affect its in vitro proliferation activity.
- The determined primary sequence and disulfide bridge information are valuable for identifying IL-2 active sites.
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