Screening for viruses using unicellular eukaryotes as hosts

Abstract

This master’s project delves into the microbial diversity of the Arctic region, with focus on the isolation and characterization of a yeast of the Cystobasidium genus and likely viruses capable of infecting it. The research also shows preliminary results pointing at the movement and chemotaxis capabilities of the yeast, presenting findings that have the potential to shape our understanding of microbial interactions in marine environments. A new species of Cystobasidium was identified. In addition, Cystobasidium was used as unicellular eukaryotic host target for viruses from a diverse sample collection obtained from Tromsø's surroundings and other regions in the Arctic. Giant virus isolation attempts utilizing Acanthamoeba as hosts was also performed as comparative analysis of a new artic host. Giant virus isolation efforts yielded the discovery of potential infectious agents, particularly in a sample from a deep-sea vent, showcasing notable structural variations in electron microscopy. The necessity for full genomic sequencing to confirm whether our Cystobasidium is a new species and to prove the viral nature of the isolated agent is emphasized throughout the study, which concludes with a contribution to enhance understanding of microbial interactions in marine environments, setting the stage for further exploration and discoveries.