bioRxiv Science⌕ Search

bioRxiv · 10.64898/2026.11.03.763947

RNA-triggered Cas12a2 antibacterial activity and resistance plasmid degradation

Abstract

Antimicrobial resistance (AMR) necessitates programmable antibacterial strategies with novel mechanisms. Here, we evaluated an inducible intracellular CRISPR/Cas12a2 system in engineered Escherichia coli targeting a chloramphenicol-resistance (Chl) transcript. Cas12a2 activation significantly delayed bacterial growth and reduced recoverable colony-forming units (CFU) by 3-log10 in vitro, and reduced bacterial burdens in a mouse skin wound model. Transcriptomic profiling revealed upregulation of recA, a key mediator of the SOS response. We therefore designed a Chl-recA dual-targeting construct, which produced a greater growth delay than either single-targeting counterpart. The optimized dual-targeting system led to an approximately 4-log10 reduction in bacterial burden in vivo. Furthermore, exploratory qPCR of culture supernatants suggested a treatment-associated decrease in amplifiable plasmid DNA. Overall, this study provides proof-of-concept for resistance-transcript-guided Cas12a2 antibacterial activity and highlights the potential of co-targeting stress-associated transcripts to enhance programmable antimicrobials.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Bai, Y., Song, Y., Gu, W., Wu, H., Liu, Y.. 2026-11-05. RNA-triggered Cas12a2 antibacterial activity and resistance plasmid degradation. https://doi.org/10.64898/2026.11.03.763947

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

1D model simulations suggest biofilms can suppress cathodic H2 bubble formation

Microbial electrosynthesis (MES) electrochemically generates H2 for the reduction of CO2 into acetate by acetogens. So far, the importance of a biofilm on the cathode of such systems remains under debate. Here, we investigated the role of cathodic biofilms through computational modelling. We developed MES-BIOFILM, a comprehensive one-dimensional model to simulate steady-state H2 and CO2 concentration gradients within cathodic biofilms, while accounting for the limited solubility of H2. The effects of key biofilm properties, including thickness, cell density and H2 consumption rate were analysed. Overall, our simulations indicate that cathodic biofilms play an important role in (1) minimizing H2 loss from the system through H2 consumption within the biofilm; and (2) suppressing H2 bubble formation by maintaining the H2 concentrations at the cathode surface below saturation. Our model predicts that the current density at which H2 bubbles begin to form can be increased by 5.5-fold relative to a bare electrode when biofilms exhibit a high cell density and high H2 consumption rate. This effect requires biofilms of at least 50 m thickness, whereas CO2 diffusion limitations arise above 200 m. These findings highlight the critical role of biofilms to increase MES performance, while requiring further experimental validation.

bioengineering↗

Cascaded Dual-Targeting (WTW/TAT) Liposomes Delivery DOX for Precision Glioblastoma Treatment

Glioblastoma (GBM) remains difficult to treat because the blood-brain barrier (BBB) and blood-tumor barrier (BTB) severely limit drug transport into tumor tissue. To address these delivery constraints, we developed a dual-targeted liposomal nanoplatform (WT-LIP) that integrates a WTW dual-targeting peptide to promote receptor-mediated BBB transcytosis and specificity to GBM and a TAT peptide to enhance post-barrier penetration and tumor-cell uptake, enabling sequential barrier crossing and GBM targeting. DOX@WT-LIP efficiently encapsulated doxorubicin (DOX) and increased endothelial transport in vitro, achieving a permeated dose of 60.74 {+/-} 2.14% at 480 min, while producing deeper transendothelial penetration and greater downstream tumor killing in a BBB/GBM co-culture. In orthotopic U251-luc models, DiD-labeled WT-LIP showed enhanced brain/tumor accumulation (G/B = 2.16 {+/-} 0.06), and DOX@WT-LIP markedly suppressed tumor growth (74.92% inhibition), improved survival, and exhibited comparatively reduced systemic toxicity. This work highlights a ligand-guided strategy that couples efficient BBB transport with tumor-selective delivery to improve GBM chemotherapy.

bioengineering↗

Biological Signaling Pathways Associated with Late Tendon Development in Chicken Embryos and Their Dependence on Mechanical Stimulation

During embryonic and neonatal development, tendons exhibit rapid changes in mechanics and structure, including increases in collagen content, crosslinking, and fibril length. These functional and structural changes are partly dependent on mechanical stimulation. However, the specific mechanobiological mechanisms driving these changes remain poorly understood. The objective of this study was to identify the potential biological mechanisms and pathways driving tendon maturation into load-bearing materials using an embryonic chick model. Using bulk RNA sequencing, gene set enrichment analysis, and transcription factor analysis, we produced a transcriptomic profile of chick hindlimb tendons during late embryonic development (E16, E18, and E20) and tendons from rigid and flaccid paralysis-treated embryos. Additionally, we assessed the results from two differential expression analysis models to improve the replicability of our findings. Our results suggest that the largest transcriptomic response occurs between embryonic day 16 and 20, and that among paralysis conditions, rigid paralysis produces the greatest effect relative to controls. Across development, we found positive enrichment in processes related to mechanotransduction, extracellular matrix remodeling, cell adhesion, and contractility, and identified candidate pathways upregulated with development, including TGF-{beta}, PI3K-AKT-mTOR, Hippo, circadian rhythm, and focal adhesion signaling. In paralysis-treated embryos, our data suggest impairment in extracellular matrix remodeling and mechanotransduction events. Specifically, we found that both modes of paralysis are associated with a cellular stress response and downregulation of WNT signaling. Together, our findings identify candidate mechanotransduction pathways that are associated with late tendon maturation and altered by paralysis, which may inform tendon tissue engineering and regenerative approaches.

bioengineering↗