Cationic heme-mimetic gallium porphyrin kills bacteria and disrupts biofilms

Wozniak-Pawlikowska, A.; Szymczak, K.; Burzynska, N.; Pieranski, M.; Goik, D.; Kubicka, M.; Rychnowski, M.; Zhang, L.; Nakonieczna, J.; Grinholc, M.

doi:10.64898/2025.12.11.693697

bioRxiv · 10.64898/2025.12.11.693697

Cationic heme-mimetic gallium porphyrin kills bacteria and disrupts biofilms

Wozniak-Pawlikowska, A.·Szymczak, K.·Burzynska, N.·Pieranski, M.·Goik, D.·Kubicka, M.·Rychnowski, M.·Zhang, L.·Nakonieczna, J.·Grinholc, M.

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Abstract

The emergence of antimicrobial resistance in ESKAPE pathogens remains a clinical challenge and limits the utility of conventional antibiotics. Antimicrobial photodynamic inactivation (aPDI) using metal porphyrins is of interest, but the activity of heme-mimetic gallium porphyrins against structured biofilms has not been well defined. In this study, we evaluated a newly synthesized cationic heme-mimetic gallium porphyrin (GaCHP-2-3) activated with visible light against biofilms formed by ESKAPE representatives under static and flow conditions and on titanium surface. Light-activated GaCHP-2-3 reduced biofilm viable counts by up to 4 log10 CFU/mL. Prolonged serial passaging of planktonic bacteria in the presence of GaCHP-2-3 for 20 passages did not yield increases in MIC, indicating no detectable resistance development under these conditions. This work presents GaCHP-2-3 aPDI as a candidate approach for biofilm control and treatment of infections where antibiotic resistance limits the option.

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Wozniak-Pawlikowska, A., Szymczak, K., Burzynska, N., Pieranski, M., Goik, D., Kubicka, M., Rychnowski, M., Zhang, L., Nakonieczna, J., Grinholc, M.. 2025-12-12. Cationic heme-mimetic gallium porphyrin kills bacteria and disrupts biofilms. https://doi.org/10.64898/2025.12.11.693697

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