Model for a novel membrane envelope in a filamentous hyperthermophilic virus
- University of Virginia, United States
- University of Washington, United States
- Institut Pasteur, France
- NIOZ Royal Netherlands Institute for Sea Research, Netherlands
Abstract
Biological membranes create compartments, and are usually formed by lipid bilayers. However, in hyperthermophilic archaea that live optimally at temperatures above 80°C the membranes are monolayers which resemble fused bilayers. Many double-stranded DNA viruses which parasitize such hosts, including the filamentous virus AFV1 of Acidianus hospitalis, are enveloped with a lipid-containing membrane. Using cryo-EM, we show that the membrane in AFV1 is a ~2 nm-thick monolayer, approximately half the expected membrane thickness, formed by host membrane-derived lipids which adopt a U-shaped 'horseshoe' conformation. We hypothesize that this unusual viral envelope structure results from the extreme curvature of the viral capsid, as 'horseshoe' lipid conformations favor such curvature and host membrane lipids that permit horseshoe conformations are selectively recruited into the viral envelope. The unusual envelope found in AFV1 also has many implications for biotechnology, since this membrane can survive the most aggressive conditions involving extremes of temperature and pH.
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Funding
National Institutes of Health (GM035269)
- Edward H Egelman
Agence Nationale de la Recherche (ANR-13-BSV3-0017-01)
- David Prangishvili
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2017, Egelman et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Model for a novel membrane envelope in a filamentous hyperthermophilic virus
eLife 6:e26268.
https://doi.org/10.7554/eLife.26268
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