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Related Experiment Video

Updated: May 10, 2026

Rapid Generation of Amyloid from Native Proteins In vitro

Rapid Generation of Amyloid from Native Proteins In vitro

Published on: December 5, 2013

A bacterial export system for generating extracellular amyloid aggregates.

Viknesh Sivanathan¹, Ann Hochschild

¹Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA, USA.

Nature Protocols

|June 22, 2013

Summary

This summary is machine-generated.

This study introduces the curli-dependent amyloid generator (C-DAG), a bacteria-based system for creating amyloid aggregates. C-DAG simplifies the identification of amyloidogenic proteins and their variants without requiring purification.

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Purification and Aggregation of the Amyloid Precursor Protein Intracellular Domain

Purification and Aggregation of the Amyloid Precursor Protein Intracellular Domain

Published on: August 28, 2012

Area of Science:

Biochemistry
Microbiology
Molecular Biology

Background:

Amyloid aggregates are implicated in various diseases.
Studying amyloid formation often requires complex in vitro methods and protein purification.

Purpose of the Study:

To present a novel bacteria-based system, the curli-dependent amyloid generator (C-DAG), for producing amyloid aggregates.
To offer a simplified method for identifying and characterizing amyloidogenic proteins.

Main Methods:

Utilizing Escherichia coli's natural curli amyloid fiber production.
Engineering heterologous amyloidogenic proteins with an N-terminal signal sequence for surface export and assembly.
Employing a curli export pathway for protein secretion and amyloid fold acquisition.

Main Results:

Demonstrated successful generation of amyloid aggregates on the bacterial cell surface.
Showcased C-DAG's ability to facilitate amyloid fold acquisition for inherently amyloidogenic proteins.
Validated C-DAG as a tool for distinguishing between amyloidogenic and non-amyloidogenic protein variants.

Conclusions:

C-DAG provides a cell-based, purification-free alternative to in vitro amyloid aggregation assays.
This system offers a straightforward approach for identifying amyloidogenic proteins and their properties.
Results can be obtained rapidly, within one week, after vector construction.