The effect of phosphorus and nitrogen limitation on viral infection in microcystis aeruginosa NIES298 using the cyanophage Ma-LMM01

<p>Throughout different times in freshwater cyanobacterial harmful algal blooms (cHAB), the availability of specific nutrients from the environment varies, causing fluctuations in the severity and species composition of a bloom. In addition to nutrient regulation of blooms, the cyanobacteria are subject to regulation by biotic factors, including phage infection. To address the potential role of cyanophages on the dominant species in most cHABs during nutrient-limited periods, we studied a specific host-phage system: Ma- LMM01 (phage) and <em>Microcystis aeruginosa</em> strain NIES298 (host), both of which originate from a eutrophic lake in Japan. The effect of phosphate and nitrogen limitation on phage and host replication was evaluated through modification of <em>M. aeruginosa</em> culture media. Growth of the host cells was monitored by culture light absorbance at 600 nm, while phage (genome) replication was quantified using real-time quantitative PCR (qPCR). Under phosphorus-limited conditions, Ma-LMM01 infected cells demonstrated a decrease in growth rate and carrying capacity compared to uninfected and infected nonlimited cultures. This relationship suggests that phage infection decreases <em>M. aeruginosa</em> growth to a greater degree under phosphorous stress than when the nutrient is readily available. In this model, these results indicate cyanophage replication may accelerate cHAB collapse under phosphorus-limiting conditions, and that increased concentrations of phosphorus may decrease the impact of cyanophage infections in the wild.</p>

Name thesis:degree_name

Master of Science (MS)

Level thesis:degree_level

Open Access Thesis

Discipline thesis:degree_discipline

Biology

Year dc:date.available

2017

Author dc:creator

• McKindles, Katelyn

Contributors dc:contributor

• Michael Angell, Ph.D. Chair
• Daniel Clemans, Ph.D.
• Steven Francoeur, Ph.D.

• Cyanophage
• HABs
• Microcystis aeruginosa
• Nitrogen limitation
• Phosphorus limitation
• Biology

Repository record dc:identifier

https://commons.emich.edu/theses/741

OAI identifier oai:identifier

oai:commons.emich.edu:theses-2122