growth phase determines gene expression and algicidal behavior of a new strain.

Fuente: PubMed
Salvato in:
Dettagli Bibliografici
Autori principali: Wiener, David, Bartolek, Zinka, Dunklin, Riley, Armbrust, E Virginia
Natura: Artículo científico
Lingua:en
Pubblicazione: mBio 2026
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1868266069673639938
author Wiener, David
Bartolek, Zinka
Dunklin, Riley
Armbrust, E Virginia
author_facet Wiener, David
Bartolek, Zinka
Dunklin, Riley
Armbrust, E Virginia
Wiener, David
Bartolek, Zinka
Dunklin, Riley
Armbrust, E Virginia
collection PubMed - marine biology
contents growth phase determines gene expression and algicidal behavior of a new strain. Wiener, David Bartolek, Zinka Dunklin, Riley Armbrust, E Virginia Diatoms Alteromonas Antibiosis Coculture Techniques Gene Expression Profiling Phytoplankton Microbial Interactions Phytoplankton-bacterium interactions are pivotal in marine ecosystems, influencing primary production and biogeochemical cycles. Diatoms, in particular, engage in diverse relationships with bacteria, ranging from mutualism to pathogenicity. However, the mechanisms governing the shift between these interactions and how they are shaped by host physiology and environmental context remain unclear. To address this, we investigated how the growth phase of the model diatom influences the behavior of an strain isolated from the Equatorial Pacific. We find that EP displays a differential algicidal impact on , depending on the growth phase of the diatom, with the greatest effect occurring during the stationary phase. The algicidal effect can be amplified to impact all growth phases by the addition of an external organic carbon source to the co-cultures. Transcriptomic analysis revealed that EP shifts from motility-associated to growth-associated gene expression patterns in response to the diatom's growth phase and co-culture duration. Bacterial cell-free exudate growth assays and fluorescence microscopy of co-cultures show a two-stage interaction model: initial bacterial swimming and exudate secretion induce diatom death, followed by bacterial aggregation around diatom debris. Comparative transcriptomics of with other algal hosts highlights host-specific bacterial responses, underscoring the context-dependent nature of these interactions. Together, these findings reveal how bacterial behavior and gene expression are modulated by host state and environmental cues, providing a molecular basis for the dynamic roles of diatom-bacterium interactions in shaping microbial community structure.IMPORTANCEDiatoms are responsible for almost a quarter of global primary production, and their ecological roles are shaped by interactions with heterotrophic bacteria. These relationships can range from mutualistic to algicidal, with consequences for nutrient cycling and carbon export. Here, we show that the growth phase of the model diatom shapes its interaction with a newly isolated open-ocean strain of . Using transcriptomics and co-culture experiments, we demonstrate that bacterial gene expression dynamically shifts with host physiology, transitioning from motility and algicidal activity to aggregation and nutrient acquisition. Our findings reveal a two-stage interaction dynamic and highlight diatom growth phase as a critical, yet often overlooked, factor in determining the outcome of bacteria-algae interactions. By linking host physiology to bacterial behavioral shifts, this study provides new insights into how microscale dynamics can scale up to influence ocean productivity and biogeochemical cycling.
format Artículo científico
id pubmed_41870039
institution PubMed
language en
publishDate 2026
publisher mBio
record_format pubmed
spellingShingle growth phase determines gene expression and algicidal behavior of a new strain.
Wiener, David
Bartolek, Zinka
Dunklin, Riley
Armbrust, E Virginia
Diatoms
Alteromonas
Antibiosis
Coculture Techniques
Gene Expression Profiling
Phytoplankton
Microbial Interactions
growth phase determines gene expression and algicidal behavior of a new strain. Wiener, David Bartolek, Zinka Dunklin, Riley Armbrust, E Virginia Diatoms Alteromonas Antibiosis Coculture Techniques Gene Expression Profiling Phytoplankton Microbial Interactions Phytoplankton-bacterium interactions are pivotal in marine ecosystems, influencing primary production and biogeochemical cycles. Diatoms, in particular, engage in diverse relationships with bacteria, ranging from mutualism to pathogenicity. However, the mechanisms governing the shift between these interactions and how they are shaped by host physiology and environmental context remain unclear. To address this, we investigated how the growth phase of the model diatom influences the behavior of an strain isolated from the Equatorial Pacific. We find that EP displays a differential algicidal impact on , depending on the growth phase of the diatom, with the greatest effect occurring during the stationary phase. The algicidal effect can be amplified to impact all growth phases by the addition of an external organic carbon source to the co-cultures. Transcriptomic analysis revealed that EP shifts from motility-associated to growth-associated gene expression patterns in response to the diatom's growth phase and co-culture duration. Bacterial cell-free exudate growth assays and fluorescence microscopy of co-cultures show a two-stage interaction model: initial bacterial swimming and exudate secretion induce diatom death, followed by bacterial aggregation around diatom debris. Comparative transcriptomics of with other algal hosts highlights host-specific bacterial responses, underscoring the context-dependent nature of these interactions. Together, these findings reveal how bacterial behavior and gene expression are modulated by host state and environmental cues, providing a molecular basis for the dynamic roles of diatom-bacterium interactions in shaping microbial community structure.IMPORTANCEDiatoms are responsible for almost a quarter of global primary production, and their ecological roles are shaped by interactions with heterotrophic bacteria. These relationships can range from mutualistic to algicidal, with consequences for nutrient cycling and carbon export. Here, we show that the growth phase of the model diatom shapes its interaction with a newly isolated open-ocean strain of . Using transcriptomics and co-culture experiments, we demonstrate that bacterial gene expression dynamically shifts with host physiology, transitioning from motility and algicidal activity to aggregation and nutrient acquisition. Our findings reveal a two-stage interaction dynamic and highlight diatom growth phase as a critical, yet often overlooked, factor in determining the outcome of bacteria-algae interactions. By linking host physiology to bacterial behavioral shifts, this study provides new insights into how microscale dynamics can scale up to influence ocean productivity and biogeochemical cycling.
title growth phase determines gene expression and algicidal behavior of a new strain.
topic Diatoms
Alteromonas
Antibiosis
Coculture Techniques
Gene Expression Profiling
Phytoplankton
Microbial Interactions
url https://pubmed.ncbi.nlm.nih.gov/41870039/