Bacterial Amyloids

  • Margery L. Evans
  • Elizabeth Gichana
  • Yizhou Zhou
  • Matthew R. Chapman
Part of the Methods in Molecular Biology book series (MIMB, volume 1779)


Many bacteria can assemble functional amyloid fibers on their cell surface. Most bacterial amyloids contribute to biofilm or other community behaviors where cells interact with a surface or with other cells. Bacterial amyloids, like all functional amyloids, share structural and biochemical properties with disease-associated eukaryotic amyloids. The general ability of amyloids to bind specific dyes, like Congo red and Thioflavin T, and their resistance to denaturation have provided useful tools for scoring and quantifying bacterial amyloid formation. Here, we present basic approaches to study bacterial amyloids by focusing on the well-studied curli amyloid fibers expressed by Enterobacteriaceae. These methods exploit the specific tinctorial and biophysical properties of amyloids. The methods described here are straightforward and can be easily applied by any modern molecular biology lab for the study of other bacterial amyloids.

Key words

Bacterial amyloids Curli Congo red dye Western blot analysis Plug Western blot analysis Overlay assay Interbacterial complementation 



Congo Red


Curli specific genes


Formic acid




Room temperature



We thank members of the Chapman laboratory for helpful discussions and review of this manuscript, especially DRS and LB. This work was supported by the National Institutes of Health Grant R01 GM118651 to MRC.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  • Margery L. Evans
    • 1
  • Elizabeth Gichana
    • 1
  • Yizhou Zhou
    • 1
  • Matthew R. Chapman
    • 1
  1. 1.Department of Molecular, Cellular, and Developmental BiologyUniversity of MichiganAnn ArborUSA

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