Targeting TPP Riboswitches Using Chimeric Antisense Oligonucleotide Technology for Antibacterial Drug Development.

Area of Science:

• Microbiology
• Molecular Biology
• Antimicrobial Research

Background:

• Multidrug-resistant bacteria pose a significant global health threat, necessitating novel antibiotic development.
• Riboswitches, particularly the Thiamine Pyrophosphate (TPP) riboswitch, are emerging as promising targets for antimicrobial strategies.
• Listeria monocytogenes presents a challenge due to intrinsic resistance to certain antibiotics.

Purpose of the Study:

• To investigate the potential of targeting the TPP riboswitch in pathogenic bacteria.
• To develop and assess an antisense oligonucleotide (ASO) for suppressing bacterial growth.
• To evaluate the specificity and efficacy of the developed ASO against Listeria monocytogenes.

Main Methods:

• Bioinformatic analysis of the TPP riboswitch and its role in thiamine pyrophosphate synthesis.
• Engineering of an antisense oligonucleotide (ASO) covalently bonded with the cell-penetrating protein pVEC.
• Testing the bacteriostatic effect of the ASO on Listeria monocytogenes and Escherichia coli.

Main Results:

• The engineered ASO demonstrated a bacteriostatic effect on Listeria monocytogenes by targeting the TPP riboswitch.
• The ASO specifically inhibited L. monocytogenes growth and showed no effect on Escherichia coli, which lacks the TPP riboswitch.
• An effective dosage of 700 nM (4.5 μg/mL) of ASO was determined to inhibit 80% of L. monocytogenes growth.

Conclusions:

• The Thiamine Pyrophosphate (TPP) riboswitch is a viable and valuable target for developing new antibacterial agents.
• Antisense oligonucleotides offer a specific and effective approach to combatting pathogenic bacteria like Listeria monocytogenes.
• This research contributes to the urgent need for novel antibiotics against multidrug-resistant pathogens.