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Related Experiment Video

Updated: Feb 13, 2026

High-Resolution Mapping of Protein-DNA Interactions in Mouse Stem Cell-Derived Neurons using Chromatin Immunoprecipitation-Exonuclease ChIP-Exo

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Bacterial exo-α-sialidases subvert the complement system through desialylation.

Kurni Kurniyati¹, Nicholas D Clark², Qin Fu³

¹Philips Institute for Oral Health Research, Virginia Commonwealth University, Richmond, VA, USA.

Biorxiv : the Preprint Server for Biology

|February 12, 2026

Summary

Bacterial sialidases disable complement immunity by removing sialic acids from immune proteins. This desialylation prevents complement activation, allowing pathogens to evade immune responses.

Keywords:

Complement evasion Complement system Glycosylation Sialidases Sialylation

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Last Updated: Feb 13, 2026

High-Resolution Mapping of Protein-DNA Interactions in Mouse Stem Cell-Derived Neurons using Chromatin Immunoprecipitation-Exonuclease ChIP-Exo

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Depletion of Specific Cell Populations by Complement Depletion

Depletion of Specific Cell Populations by Complement Depletion

Published on: February 5, 2010

Area of Science:

Immunology
Microbiology
Biochemistry

Background:

The complement system is crucial for innate immunity.
Bacterial sialidases modify host sialoglycans, but their effect on complement is unclear.

Purpose of the Study:

Investigate how bacterial sialidases impact complement immunity.
Elucidate the mechanism of complement evasion by bacterial sialidases.

Main Methods:

Utilized genetics, biochemistry, glycobiology, mass spectrometry, and structural biology.
Analyzed six sialidases from five human pathogens.
Examined interactions with complement components and regulators.

Main Results:

Demonstrated that complement components (IgG, C1q, C4, C5) and regulators (Factor I, Factor H, C4bp) are sialylated.
Showed bacterial sialidase-mediated desialylation suppresses complement activation and deposition.
Identified a conserved catalytic domain across diverse sialidases.

Conclusions:

Bacterial sialidases enable complement evasion through desialylation.
Diverse bacterial pathogens employ a conserved mechanism to disable complement immunity.