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Published on: September 30, 2014
An exported inducer peptide regulates bacteriocin production in Enterococcus faecium CTC492
1Laboratory of Microbial Gene Technology, Agricultural University of Norway, As.
Journal of Bacteriology
|April 16, 1998
Summary
Bacteriocin production in Enterococcus faecium is regulated by an induction factor (EntF). Environmental conditions like pH and solutes affect EntF
Area of Science:
- Microbiology
- Molecular Biology
- Biochemistry
Background:
- Bacteriocin production in Enterococcus faecium is crucial for antimicrobial activity.
- The regulation of bacteriocin synthesis is not fully understood.
- Enterocin A and B production in E. faecium CTC492 is strain-dependent.
Purpose of the Study:
- To identify and characterize the induction factor for enterocin A and B production.
- To investigate the influence of environmental factors on bacteriocin production.
- To elucidate the regulatory mechanism of bacteriocin synthesis.
Main Methods:
- Purification and amino acid sequencing of the induction factor.
- DNA sequencing to identify the gene encoding the induction factor.
- Culturing E. faecium under various pH and solute concentrations.
Main Results:
- Identified a 25-amino acid peptide induction factor (EntF).
- EntF gene encodes a prepeptide with a double-glycine leader peptide.
- Bacteriocin production is optimal at pH 6.2 and inhibited by low pH, NaCl, and ethanol.
- EntF induces its own synthesis and bacteriocin production, with sensitivity to environmental conditions.
Conclusions:
- EntF is a key regulator of enterocin A and B production in E. faecium.
- Environmental factors significantly modulate the response to EntF.
- Understanding this regulatory system can aid in controlling bacteriocin production for applications.
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