Virus-Host Interactions of Sulfolobus islandicus

We are investigating local adaptation in the coevolutionary interactions between Sulfolobus islandicus and mobile genetic elements such as plasmids, viruses and transposable elements. We are identifying to what extent the biogeographic distribution of mobile elements is determined by the biogeography of its hosts. We are investigating variation in the Sulfolobus immune systems that may be responsible for defining the patterns of coevolutionary interactions.

“Killer Archaea”

Our lab has recently shown that several Sulfolobus Spindle-Shaped Viruses (SSVs) confer a fitness benefit upon their host whereby it outcompetes uninfected cells in culture.  Interestingly, this effect is mediated by a toxic protein released by infected cells which kills off competitors, including ones with CRISPR-Cas immunity against the virus. The infected cells are protected against this toxicity by a yet-unknown mechanism. It is hypothesized that this phenotype may allow the virus to remove non-permissive hosts from the population, and could represent an emerging mutualism between S. islandicus and its virus.

Genomics of speciation in the model archaeon Sulfolobus islandicus

Sulfolobus islandicus has been developed as a novel model system to study the evolutionary process of speciation in domain Archaea. Genomic analysis of two sympatric S. islandicus species from one single hot spring located in Mutnovsky Volcano in Kamchatka, Russia revealed that although they can exchange genes recombination occurs at a higher frequency within than between species. We are interested in investigating the recombination rates among distinct S. islandicus species in lab as well as testing for and identifying the barriers to genetic exchange in S. islandicus by using genetic and genomic approach.

Population genomics of Sulfolobus islandicus

We are investigating the tempo and mode of archaeal genome evolution through comparative genomics of eight closely related Sulfolobus islandicus strains from biogeographically isolated geothermal environments. We are using this data to quantify the rate of horizontal gene transfer and other genome level dynamics over geologically-defined time scales.

We welcome you to explore these genomes yourself at 

Potential students who are interested in these projects should contact Rachel.