The rpoN gene of Enterococcus faecalis directs sensitivity to subclass IIa bacteriocins

Area of Science:

• Microbiology
• Molecular Biology
• Bacteriocin Research

Background:

• Subclass IIa bacteriocins are antimicrobial peptides with activity against Gram-positive bacteria.
• Listeria monocytogenes sensitivity to mesentericin Y105 involves the sigma 54 factor.
• Enterococcus faecalis is a common bacterium that can be pathogenic.

Purpose of the Study:

• To identify and characterize the rpoN gene encoding the sigma 54 factor in Enterococcus faecalis JH2-2.
• To investigate the role of the sigma 54 factor in Enterococcus faecalis sensitivity to bacteriocins.
• To determine if sigma 54 specifically affects sensitivity to subclass IIa bacteriocins.

Main Methods:

• Gene identification and knockout of the rpoN gene in Enterococcus faecalis JH2-2.
• Bacteriocin susceptibility testing using subclass IIa bacteriocins (e.g., mesentericin Y105) and class I bacteriocins (e.g., nisin).
• Phenotypic analysis of the rpoN mutant compared to the wild-type strain.

Main Results:

• The rpoN gene, encoding sigma 54, was identified in Enterococcus faecalis JH2-2.
• Interruption of the rpoN gene resulted in Enterococcus faecalis resistance to various subclass IIa bacteriocins.
• The rpoN mutant retained sensitivity to nisin, a class I bacteriocin, indicating specificity.

Conclusions:

• The sigma 54 factor (RpoN) plays a crucial role in Enterococcus faecalis sensitivity to subclass IIa bacteriocins.
• Targeting the sigma 54 factor could be a strategy to overcome resistance to specific bacteriocins.
• This finding highlights the specific involvement of sigma 54 in the bacteriocin response pathway.