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  • Individual Microcystis colonies harbour distinct bacterial communities that differ by Microcystis oligotype and with time
Title: Individual Microcystis colonies harbour distinct bacterial communities that differ by Microcystis oligotype and with time
Summary

Interactions between bacteria and phytoplankton in the phycosphere have impacts at the scale of whole ecosystems, including the development of harmful algal blooms. The cyanobacteriumMicrocystiscauses toxic blooms that threaten freshwater ecosystems and human health globally.Microcystisgrows in colonies that harbour dense assemblages of other bacteria, yet the taxonomic composition of these phycosphere communities and the nature of their interactions withMicrocystisare not well characterized. To identify the taxa and compositional variance withinMicrocystisphycosphere communities, we performed 16S rRNA V4 region amplicon sequencing on individualMicrocystiscolonies collected biweekly via high‐throughput droplet encapsulation during a western Lake Erie cyanobacterial bloom. TheMicrocystisphycosphere communities were distinct from microbial communities in whole water and bulk phytoplankton seston in western Lake Erie but lacked ‘core’ taxa found across all colonies. However, dissimilarity in phycosphere community composition correlated with sampling date and theMicrocystis16S rRNA oligotype. Several taxa in the phycosphere were specific to and conserved withMicrocystisof a single oligotype or sampling date. Together, this suggests that physiological differences betweenMicrocystisstrains, temporal changes in strain phenotypes, and the composition of seeding communities may impact community composition of theMicrocystisphycosphere.

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Award ID(s):
1736629
NSF-PAR ID:
10367840
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
Environmental Microbiology
Volume:
23
Issue:
6
ISSN:
1462-2912
Page Range / eLocation ID:
p. 3020-3036
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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