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bioRxiv · 10.1101/2025.05.02.651996

Effects of a novel Paraburkholderia phage IPK on the phenanthrene degradation efficiency of the PAH-degrading strain Paraburkholderia caledonica Bk.

Nieto, E. E.·Ghanem, N.·Cammarata, R. V.·Borim-Correa, F.·Coppotelli, B. M.·Chatzinotas, A.
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Abstract

Phages are a major cause of bacterial mortality, affecting bacterial diversity and ecosystem functioning. However, the impact of phage-host interactions in contaminated environments and their role in pollutant biodegradation have been largely overlooked. We isolated and characterized a novel phage from a polycyclic aromatic hydrocarbon (PAH)-contaminated soil that infects the PAH-degrading bacterium Paraburkholderia caledonica Bk, and investigated the effect of different multiplicity of infection (MOI) on the degradation efficiency of phenanthrene. The phage IPK is a temperate phage with a wide pH and temperature tolerance and a burst size of 80 PFC.ml{square}1. The IPK phage was classified as a member of the Caudoviricetes, related to Pseudomonas and Burkholderia phages; however, its low intergenomic similarity indicates that it belongs to a new species. Three AMGs related to amino acid metabolism and to bacterial growth regulation were identified in the phage genome. The highest multiplicity of infection (MOI 10) showed a rapid recovery of the host density abundance and greater phenanthrene degradation than MOIs ranging from 0.01 to 1. This work highlights the critical role of phage-host interactions in modulating pollutant degradation efficiency, which could be a key for improving the establishment of inoculants in bioremediation processes.

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Nieto, E. E., Ghanem, N., Cammarata, R. V., Borim-Correa, F., Coppotelli, B. M., Chatzinotas, A.. 2025-05-03. Effects of a novel Paraburkholderia phage IPK on the phenanthrene degradation efficiency of the PAH-degrading strain Paraburkholderia caledonica Bk.. https://doi.org/10.1101/2025.05.02.651996

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