TEMPERATURE CORRELATES WITH PHAGE RESISTANCE IN MICROCYSTIS AERUGINOSA NIES298

Microcystis aeruginosa is a freshwater cyanobacterium largely recognized for its role in the formation of harmful algal blooms (HABs). However, less well characterized are the host-phage interactions that occur in these toxic blooms. Here, we describe the relationship between a microcystin producing strain of M. aeruginosa, NIES298, and its lytic phage Ma-LMM01. In this study we explored how host pre-acclimation to different temperature conditions, which also affect toxin production in NIES298, influenced sensitivity to subsequent infection by Ma-LMM01. NIES298 cultures pre-acclimated to 26° C (7.15 +/- 0.02 fg cell^-1 toxin) were completely lysed whether infection occurred at 26° C or at 19° C. In contrast, 19° C acclimated NIES298 (14.13 +/- 0.20 fg cell^-1 toxin) resisted lytic infection regardless of infection temperature. To investigate key parameters driving these dynamics, a mathematical model was formulated which indicated a partially resistant subpopulation of comparable abundance in both 19° C and 26° C acclimated hosts. Specifically, we found the 19° C acclimated host subpopulation was almost completely resistant to infection, while the 26° C acclimated host subpopulation was only partially resistant. Overall, our observations demonstrate that NIES298 acclimation to a decrease in temperature played a role in the development / selection of resistance to Ma-LMM01. Ongoing efforts to better elucidate the mechanism of resistance to infection include examinations of the potential role of microcystin, whose intracellular concentration at 26° C was half that at 19° C.

Presentation Preference: Poster

Primary Presenter: Kennedi Hambrick, University of Tennessee (khambri3@vols.utk.edu)

Authors:

Kennedi Hambrick, University of Tennessee  (khambri3@vols.utk.edu)

Laura Smith, University of Tennessee  (lsmit282@utk.edu)

Robbie Martin, University of Tennessee  (rmarti49@vols.utk.edu)

Gwendolyn Stark, University of Tennessee  (gstark2@vols.utk.edu)

Bofan Wei, State University of New York College of Environmental Science and Forestry  (bwei101@syr.edu)

Gregory Boyer, State University of New York College of Environmental Science and Forestry  (glboyer@esf.edu)

David Talmy, University of Tennessee  (dtalmy@utk.edu)

Steven Wilhelm, University of Tennessee  (wilhelm@utk.edu)

Erik Zinser, University of Tennessee  (ezinser@utk.edu)