Salty Genetics: a genetic toolbox for the study of haloarchaea and their viruses

Viruses have a profound impact on members of all three domains of life, eukarya, bacteria and archaea. Archaea are single celled microorganisms which are most well known for thriving in extreme environments such as hot springs or salt lakes. They are however ubiquitous and can be found even in the human microbiome. While viruses of bacteria and eukaryotes have been studied in detail, archaeal viruses remain understudied. Therefore, this thesis aims to establish a new model system for the detailed study of archaea and their associated viruses. A halophilic (salt-loving) archaeon, Haloferax gibbonsii LR2-5, and its associated virus, HFTV1, were used for this purpose. First, both the archaeon and the virus are described in detail, granting first insights into their individual features and their interaction. Next, the archaeal host organism was genetically modified to allow for the use of more sophisticated molecular tools. Experiments showed that the modification was successful and can be used for the intended biomolecular tools.
Lastly, similar approaches to genetically modify viruses are described and first experiments are used to explore which of these could be used with the virus HFTV1. Taken together, this thesis introduces a new model system for the study of archaeal virus-host interactions.