Lipids of archaeal viruses

Abstract

Archaeal viruses represent one of the least known territory of the viral universe and even less is known about their lipids. Based on the current knowledge, however, it seems that, as in other viruses, archaeal viral lipids are mostly incorporated into membranes that reside either as outer envelopes or membranes inside an icosahedral capsid. Mechanisms for the membrane acquisition seem to be similar to those of viruses infecting other host organisms. There are indications that also some proteins of archaeal viruses are lipid modified. Further studies on the characterization of lipids in archaeal viruses as well as on their role in virion assembly and infectivity require not only highly purified viral material but also, for example, constant evaluation of the adaptability of emerging technologies for their analysis. Biological membranes contain proteins and membranes of archaeal viruses are not an exception. Archaeal viruses as relatively simple systems can be used as excellent tools for studying the lipid protein interactions in archaeal membranes.

Figure 1

Schematic representation of the currently known lipid containing archaeal viruses (C = viruses infecting crenarchaeal hosts, E = viruses infecting euryarchaeal hosts). As a comparison, an archaeal virus devoid of a membrane [32] is also shown. Membrane is illustrated as a yellow layer either inside or outside of the protein capsid depicted in purple. The viral particles are not drawn in scale.

Figure 2

Comparison of the phospholipid compositions of Har. hispanica, HHPV-1 and SH1. Concentrations are expressed as the mol% of the total phospholipids. Only phospholipids representing more than 1% of the total are shown. Error bars represent standard deviations of data from at least three independent experiments. Copyright American Society for Microbiology, [36].