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Updated: Jul 3, 2026
05:48
Rapid Generation of Amyloid from Native Proteins In vitro
Published on: December 5, 2013
Bacterial inclusion bodies contain amyloid-like structure
Lei Wang1, Samir K Maji, Michael R Sawaya
1Structural Biology Laboratory, The Salk Institute, La Jolla, California, United States of America.
Plos Biology
|August 8, 2008
Summary
Bacterial inclusion bodies, previously thought amorphous, are actually amyloid-like protein aggregates. This suggests that amyloid formation is common across life and that protein sequences evolve to prevent it.
Area of Science:
- Biochemistry
- Structural Biology
- Molecular Biology
Background:
- Protein aggregation leads to amorphous or ordered fibrils.
- Amyloid fibrils are linked to human diseases like Alzheimer's.
- Bacterial inclusion bodies were traditionally classified as amorphous aggregates.
Purpose of the Study:
- To investigate the structure of bacterial inclusion bodies.
- To determine if inclusion bodies exhibit ordered structures.
- To explore the prevalence of amyloid formation in prokaryotes.
Main Methods:
- Studied the in vivo structure of three types of bacterial inclusion bodies.
- Analyzed the structural characteristics of these aggregates.
Main Results:
- All studied inclusion bodies were found to be amyloid-like.
- These aggregates possess a cross-beta structure specific to their amino acid sequences.
- Inclusion bodies are structured, not amorphous.
Conclusions:
- Amyloid formation is a widespread process in both prokaryotes and eukaryotes.
- Protein sequences may evolve to avoid adopting amyloid conformations.
- Bacterial inclusion bodies represent a structured form of protein aggregation.
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