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The Identification of Sea Lamprey Pheromones Using Bioassay-Guided Fractionation

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Published on: July 17, 2018

Pheromone peptide cOB1 from native Enterococcus faecalis forms amyloid-like structures: A new paradigm for peptide

Shalini Gour¹, Vijay Kumar¹, Monika Rana²

¹Department of Biotechnology, Central University of Rajasthan, NH-8 Bandarsindri, Kishangarh Ajmer, 305817, Rajasthan, India.

Journal of Peptide Science : an Official Publication of the European Peptide Society

|July 19, 2019

Summary

The bacterial pheromone peptide cOB1 forms amyloid-like structures, a novel finding for quorum-sensing molecules. This discovery may impact therapeutic strategies against resistant Enterococcus faecalis strains.

Keywords:

Enterococcus faecalis MDR strains amyloids antimicrobial peptides peptide aggregation pheromone peptides

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Area of Science:

Microbiology
Biochemistry
Structural Biology

Background:

Pheromone peptides regulate bacterial communication in quorum sensing.
Enterococcus faecalis pheromone peptide cOB1 also acts as an antimicrobial peptide (AMP).
cOB1 has demonstrated antimicrobial activity against E. faecalis V583.

Purpose of the Study:

To investigate the structural properties of the pheromone peptide cOB1.
To determine if cOB1 can form amyloid-like structures.
To explore the implications of these structural properties for bacterial conjugation and therapeutics.

Main Methods:

In silico prediction of amyloidogenicity.
Congo red binding assays to detect amyloid formation.
Thioflavin T fluorescence assays.
Transmission electron microscopy (TEM) for structural visualization.

Main Results:

In silico analysis predicted cOB1 to be highly amyloidogenic.
Experimental results confirmed cOB1 forms amyloid-like aggregates.
Aggregates showed characteristic amyloid signatures: Congo red bathochromic shift, enhanced Thioflavin T fluorescence, and fibrillar morphology via TEM.

Conclusions:

The pheromone peptide cOB1 exhibits a previously unreported ability to form amyloid structures.
This amyloidogenic property could influence pheromone-receptor interactions and conjugative transfer.
Understanding cOB1's amyloid formation is crucial for developing therapeutics against multidrug-resistant E. faecalis.