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bioRxiv · 10.64898/2026.04.07.716877

A novel Flavobacterium quisquiliarum porphyrin binding protein independently disrupts Pseudomonas aeruginosa biofilms

Lelenaite, I.·Fletcher, C. S.·Houppy, W.·Morley, C.·Brown, A.·Black, G. W.·Malekpour, A. K.·Brown, N. L.·Singh, W.·Munoz, J.·Yau, H. C. L.·Lant, N.·Willats, W.
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Abstract

Bacterial biofilms underpin chronic infection and antimicrobial resistance, notably in Pseudomonas aeruginosa. Here we deconvolute a commercial alginate lyase preparation from Flavobacterium quisquiliarum and identify a previously uncharacterised [~]21 kDa porphyrin-binding protein (FqPBP). Structural, biophysical and docking analyses reveal high-affinity tetrapyrrole binding. Recombinant FqPBP independently inhibits and disperses P. aeruginosa biofilms, implicating porphyrin sequestration and iron homeostasis in biofilm control and highlighting a potential therapeutic strategy targeting iron acquisition pathways.

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Lelenaite, I., Fletcher, C. S., Houppy, W., Morley, C., Brown, A., Black, G. W., Malekpour, A. K., Brown, N. L., Singh, W., Munoz, J., Yau, H. C. L., Lant, N., Willats, W.. 2026-04-07. A novel Flavobacterium quisquiliarum porphyrin binding protein independently disrupts Pseudomonas aeruginosa biofilms. https://doi.org/10.64898/2026.04.07.716877

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