INTACT PHAGE-INFECTED MARINE CYANOBACTERIA ATTRACT CHEMOTACTIC HETEROTROPHIC BACTERIA

Dissolved chemical compounds facilitate interactions among marine microbes and ultimately drive ecosystem-scale processes such as carbon and nutrient cycling. During infection, phage manipulate host metabolism, stimulating the release of varied metabolites, including signaling molecules from intact cells. However, the impact of such compounds on microbial ecology and nutrient and energy flow is poorly understood. We determined the influence of phage infection on exometabolite release from Synechococcus strain WH8102 and the chemotactic response of heterotrophic bacteria (Vibrio alginolyticus and Psuedoalteromonas haloplanktis) using time-resolved metabolomics and microfluidics-based chemotaxis assays over the course of an infection cycle. Heterotrophic bacteria exhibited strong chemoattraction to metabolites released during early stages of infection. In addition, V. alginolyticus demonstrated sustained chemotaxis toward whole, live phage-infected Synechococcus at environmentally relevant densities and no chemotaxis toward uninfected cyanobacterial cells. Using high-throughput microfluidics we identified several compounds that act as key attractants including 5’-deoxyadenosine, 5’-methylthioadenosine, leucine and cytosine. Our findings demonstrate that prior to cell lysis phage-infected picocyanobacteria release compounds that attract motile heterotrophic bacteria and highlight a novel mechanism by which marine phage may alter resource exchange, nutrient and energy flow and microbial community composition.   

Presentation Preference: Oral

Primary Presenter: Sheri Floge, Wake Forest University (floges@wfu.edu)

Authors:

Richard Henshaw, ETH Zurich  (rhenshaw@ethz.ch)

Jonathan Moon, Wake Forest University  (moonj7@upmc.edu)

Michael Stehnach, Brandeis University  (michaelstehnach@brandeis.edu)

Benjamin Bowen, Lawrence Berkeley National Laboratory  (BPBowen@lbl.gov)

Suzanne Kosina, Lawrence Berkeley National Laboratory  (smkosina@lbl.gov)

Trent Northen, Lawrence Berkeley National Laboratory  (trnorthen@lbl.gov)

Jeffrey Guasto, Tufts University  (Jeffrey.Guasto@tufts.edu)

Sheri Floge, Wake Forest University  (floges@wfu.edu)