Archaea, constituting a distinct domain of life, exhibit unique characteristics such as the composition of their cell envelope, which is different from that of bacteria and eukaryotes.
As a consequence of this distinctiveness of the cell envelope archaeal viruses attempting to infect host cells face different challenges compared to viruses infecting other domains of life. In recent years, several receptors have been identified that are utilized by some archaeal viruses. However, our comprehension of the virus-receptor interaction in archaea remains rather scarce, despite the prevalent diversity and abundance of archaeal viruses in the environment.
Understanding the interplay between archaeal viruses and receptors is paramount to studying viral host range. Archaeal viruses may exhibit a broad (viruses can successfully infect multiple hosts of the same or even different species) or a narrow host range (they only infect closely related strains/species). The capability of certain archaeal viruses to interact with a wide array of host surface receptors may be to attributed to the exchange of host-specific genetic modules for RBPs (Receptor Binding Proteins), which was also observed in T-even bacteriophages, thereby enhancing their ability to infect a broad host range 1.
The study aims to elucidate the mechanism of host recognition utilized by tailed archaeal viruses Halorubrum tailed virus 7 (HRTV-7) and Halorubrum tailed virus 10 (HRTV-10). Both viruses infect the haloarchaeal model organisms Haloferax gibbonsii LR2-5, in addition to their original archaeal host strain Halorubrum sp. B2-2.
To achieve this objective, a combinatorial approach encompassing adsorption assays, one-step growth curves, genome sequencing, and transmission electron microscopy is employed. With this approach, we want to identify the host cell receptors required for host cell recognition and virus binding. This will aid to understand the infection mechanism of these viruses, and it will gain insight into host range determinants of tailed archaeal viruses.