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Pseudomycoicidin, a Class II Lantibiotic from Bacillus pseudomycoides
Shradha Basi-Chipalu1, Jasmin Dischinger1, Michaele Josten1
1Institute of Medical Microbiology, Immunology and Parasitology (IMMIP), University of Bonn, Bonn, Germany.
Applied and Environmental Microbiology
|March 15, 2015
Summary
Researchers discovered pseudomycoicidin, a novel lantibiotic (lanthionine-containing bacteriocin), from Bacillus pseudomycoides. This antimicrobial peptide was successfully produced in Escherichia coli, demonstrating its potential therapeutic applications.
Area of Science:
- Microbiology
- Biochemistry
- Molecular Biology
Background:
- Lantibiotics are ribosomally synthesized antimicrobial peptides featuring unique posttranslational modifications, including lanthionine and methyllanthionine bridges.
- These modifications involve dehydration of Ser/Thr residues and subsequent cyclization with Cys residues, contributing to their structural complexity and antimicrobial activity.
Purpose of the Study:
- To identify and characterize a novel lantibiotic from Bacillus pseudomycoides DSM 12442.
- To elucidate the biosynthetic pathway and confirm the antimicrobial activity of the newly discovered lantibiotic.
Main Methods:
- Bioinformatic analysis using BLAST searches with mersacidin biosynthetic enzyme (MrsM) to identify a putative lantibiotic gene cluster.
- Partial purification of the antimicrobial substance from Bacillus pseudomycoides and mass spectrometric analysis.
- Heterologous expression of the prepeptide (PseA) and modification enzyme (PseM) in Escherichia coli for structural and functional characterization.
Main Results:
- Identification of a new class II lantibiotic gene cluster in Bacillus pseudomycoides.
- Detection and partial purification of an antimicrobial substance active against Gram-positive bacteria.
- Heterologous expression confirmed the production of a modified peptide (pseudomycoicidin) with four thioether and one disulfide bridge, exhibiting antimicrobial activity after leader peptide removal.
Conclusions:
- Pseudomycoicidin is a novel lantibiotic produced by Bacillus pseudomycoides.
- Heterologous production in Escherichia coli is feasible, providing a platform for further study and potential biotechnological applications of this antimicrobial peptide.
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