NERDG 2026
Poster 2 Abstract
Programmable Antisense Nucleic Acid Mimics as Targeted Antibiotics
Hamayal Sharma, Raman Bahal
University of Connecticut
Presenting Author: Hamayal Sharma
Corresponding Author: Raman Bahal, [email protected]
Purpose
For decades, antibiotics have transformed medicine, turning deadly bacterial infections into treatable conditions. However, due to antibiotic resistance and a declining pipeline of antibiotics, bacterial infections have evolved at an alarming rate. This has led to the rise of “superbugs,” multidrug-resistant pathogens that now pose a serious threat to global health, making even last-resort therapies like vancomycin ineffective. Hence, it is essential to explore novel antimicrobial strategies.
Our project aims to use synthetic nucleic acids, such as peptide nucleic acids (PNAs), which are capable of sequence-specific recognition of bacterial mRNA, allowing targeted inhibition of essential gene expression. However, their therapeutic use is limited by inefficient intracellular delivery across bacterial cell envelopes.
Methods
In this study, we designed and evaluated chemically modified cell-penetrating peptides (CMCPPs) to improve PNA uptake through the bacterial cell wall. CMCPPs were evaluated in both Gram-positive and Gram-negative bacteria to identify effective and safe delivery strategies. Fluorescently labeled CMCPPs showed optimal and quantifiable internalization in both Gram-positive and Gram-negative bacteria, analyzed via flow cytometry. Our results indicate that CMCPPs are promising carriers for delivering antisense agents into bacteria.
Results
Building on these findings, we developed a conjugate of CMPPs with an anti-acpP PNA that targets acpP mRNA - a critical gene involved in fatty acid biosynthesis in Escherichia coli. Preliminary studies, using colony forming unit (CFU) assays, indicate effective antimicrobial activity, confirming the potential for programmable antisense PNAs as species-specific antimicrobials.
In parallel, collaborative studies extend the application of our platform to target difficult pathogens such as Pseudomonas aeruginosa, which causes chronic infections in cystic fibrosis patients, using a PNA mimic of Let-7b-5p microRNA to enhance antibiotic susceptibility and inhibit biofilm formation of P. aeruginosa.
Conclusion
Our findings demonstrate that RNA-directed nucleic acid therapies, combined with rationally designed CMPPs, can overcome the permeability barriers typically associated with antimicrobial approaches. The programmability of this technique enables rapid redesign of PNA sequences to target various bacterial RNAs, including those associated with virulence and antibiotic resistance genes, potentially resensitizing bacteria to existing antibiotics. This work provides a foundation for developing next-generation nucleic acid-based antimicrobials against multidrug-resistant pathogens.
Keywords
Antimicrobial resistance, Nucleic-acid therapeutics, Precision antibiotics, Peptide nucleic acids, Cell-penetrating peptides
Poster 2 Abstract
Programmable Antisense Nucleic Acid Mimics as Targeted Antibiotics
Hamayal Sharma, Raman Bahal
University of Connecticut
Presenting Author: Hamayal Sharma
Corresponding Author: Raman Bahal, [email protected]
Purpose
For decades, antibiotics have transformed medicine, turning deadly bacterial infections into treatable conditions. However, due to antibiotic resistance and a declining pipeline of antibiotics, bacterial infections have evolved at an alarming rate. This has led to the rise of “superbugs,” multidrug-resistant pathogens that now pose a serious threat to global health, making even last-resort therapies like vancomycin ineffective. Hence, it is essential to explore novel antimicrobial strategies.
Our project aims to use synthetic nucleic acids, such as peptide nucleic acids (PNAs), which are capable of sequence-specific recognition of bacterial mRNA, allowing targeted inhibition of essential gene expression. However, their therapeutic use is limited by inefficient intracellular delivery across bacterial cell envelopes.
Methods
In this study, we designed and evaluated chemically modified cell-penetrating peptides (CMCPPs) to improve PNA uptake through the bacterial cell wall. CMCPPs were evaluated in both Gram-positive and Gram-negative bacteria to identify effective and safe delivery strategies. Fluorescently labeled CMCPPs showed optimal and quantifiable internalization in both Gram-positive and Gram-negative bacteria, analyzed via flow cytometry. Our results indicate that CMCPPs are promising carriers for delivering antisense agents into bacteria.
Results
Building on these findings, we developed a conjugate of CMPPs with an anti-acpP PNA that targets acpP mRNA - a critical gene involved in fatty acid biosynthesis in Escherichia coli. Preliminary studies, using colony forming unit (CFU) assays, indicate effective antimicrobial activity, confirming the potential for programmable antisense PNAs as species-specific antimicrobials.
In parallel, collaborative studies extend the application of our platform to target difficult pathogens such as Pseudomonas aeruginosa, which causes chronic infections in cystic fibrosis patients, using a PNA mimic of Let-7b-5p microRNA to enhance antibiotic susceptibility and inhibit biofilm formation of P. aeruginosa.
Conclusion
Our findings demonstrate that RNA-directed nucleic acid therapies, combined with rationally designed CMPPs, can overcome the permeability barriers typically associated with antimicrobial approaches. The programmability of this technique enables rapid redesign of PNA sequences to target various bacterial RNAs, including those associated with virulence and antibiotic resistance genes, potentially resensitizing bacteria to existing antibiotics. This work provides a foundation for developing next-generation nucleic acid-based antimicrobials against multidrug-resistant pathogens.
Keywords
Antimicrobial resistance, Nucleic-acid therapeutics, Precision antibiotics, Peptide nucleic acids, Cell-penetrating peptides
