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Updated: Feb 12, 2026

Introducing Shear Stress in the Study of Bacterial Adhesion
Published on: September 2, 2011
Analysis of Bacterial Pilus Assembly by Shearing and Immunofluorescence Microscopy
Areli Luna-Rico1, Jenny-Lee Thomassin1, Olivera Francetic2
1Biochemistry of Macromolecular Interactions Unit, Department of Structural Biology and Chemistry, CNRS UMR3528, Institut Pasteur, Paris Cedex 15, France.
Abstract:
Bacterial surface appendages of the type 4 pilus superfamily play diverse roles in adherence, aggregation, motility, signaling, and macromolecular transport. Here we describe two analytical approaches to study assembly of type 4 pili and of pseudopili produced by type 2 protein secretion systems: the shearing assay and immunofluorescence microscopy. These complementary antibody-based methods allow for semiquantitative analysis of fiber assembly. The shearing assay can be scaled up to yield crude extracts of pili that can be further analyzed by electron and atomic force microscopy or by mass spectrometry.
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