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Updated: Jun 15, 2026
08:02
Synchronization of Caulobacter Crescentus for Investigation of the Bacterial Cell Cycle
Published on: April 8, 2015
A localized multimeric anchor attaches the Caulobacter holdfast to the cell pole
Gail G Hardy1, Rebecca C Allen, Evelyn Toh
1Department of Biology, Jordan Hall 142, Indiana University, 1001 E. 3rd Street, Bloomington, IN 47405, USA.
Molecular Microbiology
|March 18, 2010
Summary
Caulobacter crescentus uses HfaA, HfaB, and HfaD proteins for outer membrane anchoring of the holdfast. HfaB is crucial for stability and translocation, facilitating cell attachment.
Area of Science:
- Microbiology
- Cell Biology
- Biochemistry
Background:
- Caulobacter crescentus attachment relies on the holdfast, a polysaccharide structure.
- The holdfast is anchored to the cell surface by HfaA, HfaB, and HfaD proteins.
Purpose of the Study:
- To investigate the roles of HfaA, HfaB, and HfaD in holdfast assembly and cell attachment.
- To elucidate the localization and interactions of these key anchoring proteins.
Main Methods:
- Protein localization studies using microscopy.
- Analysis of mutant phenotypes for adherence and holdfast attachment.
- Investigation of protein multimerization and stability.
Main Results:
- HfaA, HfaB, and HfaD are surface-exposed outer membrane proteins.
- HfaA and HfaD form homomultimers, requiring HfaB for stability and outer membrane translocation.
- HfaB is essential for holdfast attachment, with mutants showing severe deficiencies.
Conclusions:
- HfaB likely secretes HfaA and HfaD across the outer membrane.
- The HfaA, HfaB, and HfaD complex anchors the holdfast to the stalk, mediating bacterial adhesion.
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