Coexistence of marine viruses and their phytoplankton hosts: Virus competition for hosts
Viruses are important regulators of phytoplankton population dynamics and species succession, and viral infection is a key driver for host diversity. In marine environments, a large variety of viruses and phytoplankton hosts are known to coexist, showing specific succession patterns for host and virus strains. However, the mechanisms and dynamics behind virus competition and host-virus coexistence are, thus far, only poorly understood. Moreover, it is now becoming clear that environmental factors such as light or temperature affect host-virus interactions. Global climate change is expected to lead to an increase in water temperature as well as a change in water column mixing regimes and consequently light intensity
and duration. These changes will most likely also impact and alter virus-host dynamics. We conduct detailed laboratory studies aimed at unravelling how virus competition for the same host affect phytoplankton host-virus infection dynamics and virus production, and how changes in environmental conditions affect these dynamics.
These experiments involve semi-continuous culturing of the algal host species and their respective viruses under various growth regimes. Host cultures will then be inoculated with multiple viruses at the same time and the infection cycle will be closely monitored for virus and algal host abundances, which are analysed using flow cytometry. The latent period, viral production and burst size will be determined. In addition, progeny virus will be analysed for infectivity. Moreover, molecular techniques such as qPCR will be employed to target and quantify the competing viruses individually.
This project is suitable for MSc students. Projects have a planned duration of 6 - 8 months and will take place at NIOZ, Texel.
If you are interested, please contact Prof. Dr. Corina Brussaard (Corina.Brussaard@nioz.nl).