Linkage between copepods and bacteria in the North Atlantic Ocean

• Published in: Aquatic Microbial Ecology
• Main Authors: De Corte, D., Lekunberri, I., Sintes, E., Garcia, J.A.L., Gonzalez, S., Herndl, G.J.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2014
• Subjects: North Atlantic; Copepods
• Online Access: https://www.vliz.be/imisdocs/publications/79/264079.pdf

Copepods and bacteria are fundamental components of the pelagic food web andplay a major role in biogeochemical cycles. Marine bacteria have a free-living or particleattachedlifestyle, but as members of the microbial food web, the only biotic interaction of bacteriais commonly assumed to be with their predators (protists and/or viruses). However, acopepod’s body is highly enriched in organic matter and harbors a large and complex bacterialcommunity. The aim of this study was to compare the composition of the free-living bacterialcommunity of the open Atlantic to that associated with copepods. We used 454 highthroughputsequencing of the 16S rRNA gene to decipher the bacterial community compositionassociated with this zooplankton group and the ambient water. Significant differences werefound between the bacterial communities associated with the dominant copepod families(Calanoida: Centropagidae and Clausocalanidae; Cyclopoida: Corycaeidae, Oncaeidae, andLubbockiidae) and the ambient water. Bacilli and Actinobacteria dominated the copepodassociatedcommunity and Alphaproteobacteria, Deltaproteobacteria, and Synechococcus dominatedthe free-living community. However, the presence of shared bacterial operational taxonomicunits (OTUs) between these 2 distinct habitats suggests a dynamic exchange of bacteriabetween seawater and copepods. Taken together, our results support the hypothesis that theinterior and exterior surfaces of copepods provide a specific niche with a strong selective pressurefor bacteria.