Abstract
A new type of viral-induced lysis system has recently been discovered for two unrelated archaeal viruses, STIV and SIRV2. Prior to the lysis of the infected host cell, unique pyramid-like lysis structures are formed on the cell surface by the protrusion of the underlying cell membrane through the overlying external S-layer. It is through these pyramid structures that assembled virions are released during lysis. The STIV viral protein c92 is responsible for the formation of these lysis structures. We searched for c92-like proteins in viral sequences present in multiple viral and cellular metagenomic libraries from Yellowstone National Park acidic hot spring environments. Phylogenetic analysis of these proteins demonstrates that, although c92-like proteins are detected in these environments, some are quite divergent and may represent new viral families. We hypothesize that this new viral lysis system is common within diverse archaeal viral populations found within acidic hot springs.
Highlights
Compared to the viruses infecting organisms from the domains Bacteria and Eukarya, few viruses infecting archaeal organisms have been isolated and most are poorly understood in molecular detail
The unique viral lysis system described for Sulfolobus turreted icosahedral virus (STIV) [12, 14] and SIRV2 [18,19,20] appears within the archaeal viral community associated within YNP acidic hot springs
By comparing STIV c92 and homologues in rudiviral genomes against our YNP viral and cellular metagenomic databases, we found 70 contigs coding for protein sequences that represent closely related proteins
Summary
Compared to the viruses infecting organisms from the domains Bacteria and Eukarya, few viruses infecting archaeal organisms have been isolated and most are poorly understood in molecular detail. Sulfolobus turreted icosahedral virus (STIV) has emerged as a model system for examining archaeal virus replication and structure [5,6,7,8,9,10,11,12,13,14,15]. The cryoelectron microscopy image reconstruction of STIV particles revealed a pseudo T = 31 capsid, an internal membrane, and turret-like projections extending from each of the virions fivefold axes [15]. Structural analysis of the major capsid protein has suggested an evolutionary link between archaeal viruses and bacterial and eukaryotic viruses [7, 15]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
