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Title: Heterotrophic bacteria trigger transcriptome remodelling in the photosynthetic picoeukaryote Micromonas commoda
Abstract Marine biogeochemical cycles are built on interactions between surface ocean microbes, particularly those connecting phytoplankton primary producers to heterotrophic bacteria. Details of these associations are not well understood, especially in the case of direct influences of bacteria on phytoplankton physiology. Here we catalogue how the presence of three marine bacteria (Ruegeria pomeroyiDSS‐3,Stenotrophomonassp. SKA14 andPolaribacter dokdonensisMED152) individually and uniquely impact gene expression of the picoeukaryotic algaMicromonas commodaRCC 299. We find a dramatic transcriptomic remodelling byM. commodaafter 8 h in co‐culture, followed by an increase in cell numbers by 56 h compared with the axenic cultures. Some aspects of the algal transcriptomic response are conserved across all three bacterial co‐cultures, including an unexpected reduction in relative expression of photosynthesis and carbon fixation pathways. Expression differences restricted to a single bacterium are also observed, with the FlavobacteriiaP. dokdonensisuniquely eliciting changes in relative expression of algal genes involved in biotin biosynthesis and the acquisition and assimilation of nitrogen. This study reveals thatM. commodahas rapid and extensive responses to heterotrophic bacteria in ways that are generalizable, as well as in a taxon specific manner, with implications for the diversity of phytoplankton‐bacteria interactions ongoing in the surface ocean.  more » « less
Award ID(s):
2019589
PAR ID:
10559570
Author(s) / Creator(s):
; ;
Publisher / Repository:
Wilely-Blackwell
Date Published:
Journal Name:
Environmental Microbiology Reports
Volume:
16
Issue:
3
ISSN:
1758-2229
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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