Phage proofing Pseudomonas putida uncovers novel broad-spectrum phage resistance protein Psh
- 1Sandia National Laboratories
Abstract
Broad-spectrum phage resistance offers an important layer of protection against bacterial fermenter crashes during biomanufacturing processes, yet the underlying mechanisms are often poorly defined or come at a fitness cost. Using experimental evolution, we generated two Pseudomonas putida strains that were resistant to at least six phage genera. Genome sequencing revealed a single frameshift deletion in each strain that restored functionality of a Type I secretion system (T1SS) ATPase. We also found strong transcriptional upregulation of a nearby protein, PP_1794, which we coin Phage shielding helix rich protein (Psh). Overexpression experiments show that Psh protein is secreted by this restored T1SS to confer complete phage resistance. When compared to wild-type P. putida KT2440, no growth or expression defects were evident, but pyoverdine production was reduced. The Psh gene and T1SS are widely distributed across Gram-negative bacteria. These findings uncover a previously uncharacterized phage defense system in P. putida based on secretion-mediated receptor masking.
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BibTeX
@misc{diaz2026phage,
title = {{Phage proofing Pseudomonas putida uncovers novel broad-spectrum phage resistance protein Psh}},
author = {B. Diaz and S. Won and J. D. Jaryenneh and M. M. Rahman and V. R. Chourasia and C. M. Mageeney},
howpublished = {bioRxiv},
year = {2026},
month = sep,
doi = {10.64898/2026.09.02.748959},
url = {https://www.biorxiv.org/content/10.64898/2026.09.02.748959v1},
note = {CC BY-NC-ND},
}
RIS
TY - UNPB
TI - Phage proofing Pseudomonas putida uncovers novel broad-spectrum phage resistance protein Psh
AU - B. Diaz
AU - S. Won
AU - J. D. Jaryenneh
AU - M. M. Rahman
AU - V. R. Chourasia
AU - C. M. Mageeney
PY - 2026
DA - 2026/09/02
PB - bioRxiv
DO - 10.64898/2026.09.02.748959
UR - https://www.biorxiv.org/content/10.64898/2026.09.02.748959v1
AB - Broad-spectrum phage resistance offers an important layer of protection against bacterial fermenter crashes during biomanufacturing processes, yet the underlying mechanisms are often poorly defined or come at a fitness cost. Using experimental evolution, we generated two Pseudomonas putida strains that were resistant to at least six phage genera. Genome sequencing revealed a single frameshift deletion in each strain that restored functionality of a Type I secretion system (T1SS) ATPase. We also found strong transcriptional upregulation of a nearby protein, PP_1794, which we coin Phage shielding helix rich protein (Psh). Overexpression experiments show that Psh protein is secreted by this restored T1SS to confer complete phage resistance. When compared to wild-type P. putida KT2440, no growth or expression defects were evident, but pyoverdine production was reduced. The Psh gene and T1SS are widely distributed across Gram-negative bacteria. These findings uncover a previously uncharacterized phage defense system in P. putida based on secretion-mediated receptor masking.
ER -