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Updated: Aug 9, 2025
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Expression, Purification, and Antimicrobial Activity of S100A12
Published on: May 13, 2017
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Post-translational modifications on the metal-sequestering protein calprotectin
Elizabeth M Nolan1, Janet J Y Peet2
1Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA. lnolan@mit.edu.
Summary
Human calprotectin (CP) uses post-translational modifications (PTMs) to adapt its function in innate immunity. These modifications create diverse CP proteoforms, impacting its role in nutritional immunity against microbial pathogens.
Area of Science:
- Immunology
- Biochemistry
- Microbiology
Background:
- Human calprotectin (CP), an S100A8/S100A9 oligomer, is a key neutrophil protein in innate immunity.
- CP sequesters extracellular metal ions, limiting nutrient availability for microbial pathogens and inhibiting their growth.
Purpose of the Study:
- To review post-translational modifications (PTMs) on human calprotectin (CP) subunits.
- To highlight recent studies on the structural and functional impacts of methionine and cysteine oxidation on CP.
Main Methods:
- Literature review of fundamental and clinical studies on CP PTMs.
- Analysis of recent research evaluating the consequences of CP subunit oxidation.
Main Results:
- CP subunits (S100A8 and S100A9) undergo diverse PTMs.
- Methionine and cysteine oxidation significantly affect CP structure and function.
- Extracellular CP exists as a complex mixture of multiple proteoforms.
Conclusions:
- PTMs generate distinct CP proteoforms with potentially altered biological functions and lifespans.
- Understanding PTMs is crucial for a comprehensive model of CP's role in nutritional immunity.
- Modified CP species must be integrated into current nutritional immunity models.
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