Tools for characterizing bacterial protein synthesis inhibitors

Area of Science:

• Microbiology
• Molecular Biology
• Drug Discovery

Background:

• Antibiotic resistance necessitates the discovery of novel protein synthesis inhibitors.
• Current methods for identifying antibiotic targets and modes of action are often slow and inefficient.
• Dereplication of known antibiotic scaffolds from complex extracts is a major bottleneck in drug discovery.

Purpose of the Study:

• To develop a rapid, two-pronged approach for characterizing inhibitors of protein synthesis (ChIPS).
• To enable swift identification of the antibiotic target site and mode of action on the bacterial ribosome.
• To improve the process of dereplication for chemically complex natural product extracts.

Main Methods:

• Engineering hypersensitive Escherichia coli strains with single rRNA operons to isolate resistance mutants.
• Utilizing rRNA mutations to pinpoint the antibiotic's site of action.
• Monitoring drug-induced ribosome stalling on mRNA via primer extension to elucidate the mode of action.

Main Results:

• Demonstrated a rapid and efficient method for identifying the site and mode of action of translation inhibitors.
• Successfully validated the ChIPS approach on a bacterial extract containing an unknown metabolite.
• Rapidly detected the presence of the antibiotic chloramphenicol in the validated extract.

Conclusions:

• The ChIPS approach provides a fast and effective strategy for characterizing novel protein synthesis inhibitors.
• This method accelerates the identification of antibiotic mechanisms, aiding in the discovery of new antibacterial agents.
• Facilitates efficient dereplication, saving time and resources in the search for novel lead molecules.