Virus–host interactions in environments with a wide range of ionic strengths

Abstract

Although high-salt environments are rich in viruses, virus-host interactions have not been much explored. Here we study the virus-host interactions occurring in a variety of salt environments, up to saturated salinity. We chose viruses from different environments with diverse morphologies that included both bacterial and archaeal viruses. To extend the test virus set five new haloviruses were isolated and initially characterized in this study. We observed adsorption rates that varied over four orders of magnitude among the virus-host cell systems used in this study. Changes in ionic strength affected the adsorption of these viruses to their host cells in a variety of ways. All the studied viruses, regardless from which environment they were isolated, were more resistant to variations in ionic strength conditions than their host cells. Our study provides a glimpse of the early events in virus life cycles for a number of viruses from different environments. We also gained information on viral responses to changing environments, a valuable piece of information in extending our understanding of the viruses in the environment.

First Insights into the Entry Process of Hyperthermophilic Archaeal Viruses

“…is surprising, given that viruses of halophilic archaea-the only group of archaeal viruses for which adsorption has been studied-often bind to their hosts extremely slowly (46). For example, only 30% of salterprovirus His1 (47,48) and Halo- arcula hispanica tailed virus 1 (HHTV-1; Siphoviridae) (46) virions adsorb in 3 h. The fast adsorption of SIRV2 is consistent with recent transcriptomics data revealing that transcription of the early SIRV2 genes starts within 1 min of infection (49).…”

Salinity influences disease-induced mortality of the oyster Crassostrea gigas and infectivity of the ostreid herpesvirus 1 (OsHV-1)

“…Different letters indicate significant differences ronmental parameters such as salinity. This type of virus is generally more susceptible to environmental changes than non-enveloped viruses (Lucas 2001, Kukkaro & Bamford 2009. Prior acclimation to salinity plays a major role in the host response to a pathogen.…”

“…For instance, the optimal salinity for the growth of pathogenic strains of Vibrio splendidus and V. aestuarianus is approximately 20 ‰ (Vezzulli et al 2015). To our knowledge, no information is available on the precise effects of salinity on eukaryotic marine viruses, but for viruses that infect bacteria, salinity influences viral adhesion to the hosts or genome injection by altering their envelope or capsid (Cordova et al 2003, Kukkaro & Bamford 2009, Mojica & Brussaard 2014.…”

New, Closely Related Haloarchaeal Viral Elements with Different Nucleic Acid Types

“…hispanica culture (1.5 ϫ 10 9 CFU/ml) was infected with HHPV-1 stock (multiplicity of infection [MOI] of 15). After an adequate adsorption period of 30 min (5 min at 22°C with no aeration, followed by 25 min at 37°C with aeration [43]), the cells were washed with MGM broth to remove the unbound viruses and resuspended into 30 ml of MGM broth. The culture was incubated at 37°C with aeration.…”