DNA Aptamers Mediated Inhibition of Pathogenic Erm42 Enzyme Involved in Antimicrobial Resistance

Area of Science:

• Molecular Biology
• Biochemistry
• Drug Discovery

Background:

• Antimicrobial resistance (AMR) is a growing threat driven by pathogen resistance mechanisms.
• Erythromycin-resistant methyltransferase (Erm) enzymes confer resistance to multiple antibiotics by modifying ribosomal RNA (rRNA).
• Specific inhibitors for Erm enzymes, particularly Erm42, are lacking.

Purpose of the Study:

• To discover and characterize high-affinity DNA aptamers targeting the pathogenic Erm42 methyltransferase.
• To evaluate the inhibitory potential of these aptamers against Erm42-mediated rRNA methylation.
• To develop novel DNA aptamer-based tools for combating AMR.

Main Methods:

• In vitro selection (SELEX) was used to identify DNA aptamers against Erm42.
• Binding affinity was assessed using techniques like surface plasmon resonance (SPR) or similar.
• Inhibitory activity was confirmed by measuring the reduction in rRNA methylation.
• DNase I footprinting assays were employed to characterize aptamer binding and engineer truncated versions.

Main Results:

• Two high-affinity DNA aptamers, Apt-E1 and Apt-E2, were identified with nanomolar binding affinity for Erm42.
• These aptamers effectively inhibited the methyltransferase activity of Erm42.
• Engineered truncated aptamers demonstrated comparable binding and enhanced specificity for Erm42.
• Specificity was validated against other methyltransferases and DNA-binding proteins.

Conclusions:

• Novel DNA aptamers targeting Erm42 have been developed.
• These aptamers represent a promising new strategy for inhibiting Erm-mediated AMR.
• The findings pave the way for developing aptamer-based therapeutics and diagnostics to combat multidrug-resistant pathogens.