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bioRxiv · 10.64898/2026.02.02.703343

Time-resolved transcriptomic mapping reveals conserved stress programs and metabolic rewiring in Escherichia coli under antimicrobial photodynamic and blue light exposure.

Burzynska, N.·Szczesniak, M.·Grinholc, M.
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Abstract

Antimicrobial photodynamic inactivation (aPDI) and antimicrobial blue light (aBL) are emerging, resistance-agnostic strategies for controlling bacterial pathogens, yet their systems-level impact on prokaryotic physiology remains incompletely understood. Here, we used time-resolved global transcriptomics to define how Escherichia coli reprograms gene expression in response to diverse photodynamic stresses. E. coli K-12 BW25113 was exposed to five phototreatments differing in photosensitizer chemistry and light wavelength, including rose bengal, TMPyP, new methylene blue, aBL alone, and aBL combined with 5-aminolevulinic acid, and transcriptional responses were profiled after short (30 min) and prolonged (7-8 h) exposure. Short-term phototreatments triggered rapid and extensive transcriptional remodeling, affecting up to [~]58% of the genes and dominated by conserved stress programs including oxidative defense, sulfur metabolism, and a broad downshift in biosynthesis and energy generation. In contrast, prolonged exposure elicited more restrained but highly treatment-specific adaptive responses, characterized by suppression of core energy metabolism, including oxidative phosphorylation and the tricarboxylic acid cycle, coupled with activation of alternative catabolic pathways. Together, these findings reveal a common acute stress architecture across photodynamic modalities followed by divergent long-term adaptive trajectories, providing a systems-level framework for understanding bacterial responses to light-based antimicrobials and informing the rational optimization of photodynamic therapies. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=66 SRC="FIGDIR/small/703343v1_ufig1.gif" ALT="Figure 1"> View larger version (22K): org.highwire.dtl.DTLVardef@a990a1org.highwire.dtl.DTLVardef@5670bcorg.highwire.dtl.DTLVardef@1035840org.highwire.dtl.DTLVardef@96ff67_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Burzynska, N., Szczesniak, M., Grinholc, M.. 2026-02-05. Time-resolved transcriptomic mapping reveals conserved stress programs and metabolic rewiring in Escherichia coli under antimicrobial photodynamic and blue light exposure.. https://doi.org/10.64898/2026.02.02.703343

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