Family of viruses
Lipothrixviridae
is a family of
viruses
in the order
Ligamenvirales
.
Thermophilic
archaea
in the phylum
Thermoproteota
serve as natural hosts. There are 11 species in this family, assigned to 4 genera.
[1]
[2]
[3]
[4]
[5]
Taxonomy
[
edit
]
The following genera and species are assigned to the family:
[2]
The family consists of three genera:
Alphalipothrixvirus
,
Betalipothrixvirus
, and
Deltalipothrixvirus
.
Captovirus
used to be in this family as the genus Gammalipothrixvirus, but now it is the only genus in the family
Ungulaviridae
.
[6]
[7]
They are classified into genera based on their genomic properties and on the diversity of their terminal appendages, which are involved in host cell recognition. The originally proposed genus
Alphalipothrixvirus
was renamed
Alphatristromavirus
and moved to family
Tristromaviridae
.
[8]
[9]
In 2020, the genus
Alphalipothrixvirus
was recreated for classification of Sulfolobus filamentous virus 1
[10]
and Sulfolobales Beppu filamentous virus 2.
[11]
In the genus
Gammalipothrixvirus
claw-like structures are found at either end of the virion.
Members of the
Lipothrixviridae
share structural and genomic characteristics with viruses from the
Rudiviridae
family, which contains non-enveloped rod-shaped viruses. Viruses from the two families have linear dsDNA genomes and share up to nine genes. In addition, the filamentous particles of rudiviruses and lipothrixviruses are built from structurally similar, homologous major capsid proteins. Due to these shared properties viruses from the two families are classified into an order
Ligamenvirales
.
[12]
Members of the
Ligamenvirales
are structurally related to viruses of the family
Tristromaviridae
which, similar to lipothrixviruses, are enveloped and encode two paralogous major capsid proteins with the same fold as those of ligamenviruses.
[13]
Due to these structural similarities, order
Ligamenvirales
and family
Tristromaviridae
were proposed to be unified within a class 'Tokiviricetes' (toki means ‘thread’ in Georgian and
viricetes
is an official suffix for a virus class).
[13]
Virology
[
edit
]
The viruses are enveloped and filamentous. The capsid varies considerably in length ? 410?1950 nanometers (nm) ? and is 24?38 nm in diameter. The envelope has a monolayer structure and includes di-phytanyl tetraethers lipids.
[
citation needed
]
From either end of the viron are protrusions extending from the core through the envelope. The capsid itself is elongated and exhibits helical symmetry. The core itself is helical.
[
citation needed
]
There are two major capsid proteins (MCP1 and MCP2). MCP1 and MCP2 form a heterodimer, which wraps around the linear dsDNA genome transforming it into A-form. Interaction between the genome and the MCPs leads to condensation of the genome into the virion superhelix.
[10]
[14]
[15]
Genomes are linear, up to 40 kb in length.
[1]
Genus
|
Structure
|
Symmetry
|
Capsid
|
Genomic arrangement
|
Genomic segmentation
|
Alphalipothrixvirus
|
Filamentous
|
Helical
|
Enveloped
|
Linear
|
Monopartite
|
Betalipothrixvirus
|
Filamentous
|
Helical
|
Enveloped
|
Linear
|
Monopartite
|
Deltalipothrixvirus
|
Filamentous
|
Helical
|
Enveloped
|
Linear
|
Monopartite
|
Life cycle
[
edit
]
Viral replication is cytoplasmic. Entry into the host cell is achieved by adsorption to the host cell. Acidianus filamentous virus 1 was found to bind to cellular pili-like appendages. DNA templated transcription is the method of transcription. Archaea serve as the natural host. Transmission routes are passive diffusion.
[1]
Virion assembly and egress have been studied in the case of
Sulfolobus islandicus filamentous virus
(SIFV). The virions assemble inside the cell. Binding of the major capsid protein dimers to the linear dsDNA genome lead to the assembly of nucleocapsids, which are subsequently enveloped intracellularly through an unknown mechanism.
[16]
All lipothrixviruses are likely to be lytic viruses. In the case of betalipothrixviruses and deltalipothrixviruses, virions are released through pyramidal portals, referred to as virus-associated pyramids (VAPs). The VAPs of SIFV have a hexagonal base (i.e., constructed from six triangular facets).
[16]
Genus
|
Host details
|
Tissue tropism
|
Entry details
|
Release details
|
Replication site
|
Assembly site
|
Transmission
|
Alphalipothrixvirus
|
Archaea:
Saccharolobus
|
None
|
Injection
|
Unknown
|
Cytoplasm
|
Cytoplasm
|
Passive diffusion
|
Betalipothrixvirus
|
Archaea:
Acidianus
,
Saccharolobus
|
None
|
Injection
|
Lytic
|
Cytoplasm
|
Cytoplasm
|
Passive diffusion
|
Deltalipothrixvirus
|
Archaea:
Acidianus
|
None
|
Injection
|
Lytic
|
Cytoplasm
|
Cytoplasm
|
Passive diffusion
|
References
[
edit
]
- ^
a
b
c
"Viral Zone"
. ExPASy
. Retrieved
15 June
2015
.
- ^
a
b
"Virus Taxonomy: 2020 Release"
. International Committee on Taxonomy of Viruses (ICTV). March 2021
. Retrieved
14 May
2021
.
- ^
Arnold, H.P., Zillig, W., Ziese, U., Holz, I., Crosby, M., Utterback, T., Weidmann, J.F., Kristjanson, J.K., Klenk, H.P., Nelson, K.E. and Fraser, C.M. (2000). A novel lipothrixvirus, SIFV, of the extremely thermophilic crenarchaeon Sulfolobus. Virology, 267, 252?266.
- ^
Janekovic, D., Wunderl S, Holz I, Zillig W, Gierl A, Neumann H (1983) TTV1, TTV2 and TTV3, a family of viruses of the extremely thermophilic anaerobic, sulphur reducing, archaeabacterium Thermoproteus tenax. Mol. Gen. Genet. 19239?19245
- ^
Bettstetter, M., Peng, X., Garrett, R.A. and Prangishvili, D. (2003). AFV-1, a novel virus infecting hyperthermophilic archaea of the genus Acidianus. Virology, 315, 68?79.
- ^
"Current ICTV Taxonomy Release | ICTV"
.
- ^
Haring M, Vestergaard G, Brugger K, Rachel R, Garrett RA, Prangishvili D (2005) Structure and genome organization of AFV2, a novel archaeal lipothrixvirus with unusual terminal and core structures. J Bacteriol 187(11): 3855?3858
doi
:
10.1128/JB.187.11.3855-3858.2005
- ^
Prangishvili, D; Rensen, E; Mochizuki, T; Krupovic, M; ICTV Report, Consortium (February 2019).
"ICTV Virus Taxonomy Profile: Tristromaviridae"
.
The Journal of General Virology
.
100
(2): 135?136.
doi
:
10.1099/jgv.0.001190
.
PMID
30540248
.
- ^
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.
- ^
a
b
Liu, Y; Osinski, T; Wang, F; Krupovic, M; Schouten, S; Kasson, P; Prangishvili, D; Egelman, EH (2018).
"Structural conservation in a membrane-enveloped filamentous virus infecting a hyperthermophilic acidophile"
.
Nature Communications
.
9
(1): 3360.
Bibcode
:
2018NatCo...9.3360L
.
doi
:
10.1038/s41467-018-05684-6
.
PMC
6105669
.
PMID
30135568
.
- ^
Liu, Y; Brandt, D; Ishino, S; Ishino, Y; Koonin, EV; Kalinowski, J; Krupovic, M; Prangishvili, D (2019). "New archaeal viruses discovered by metagenomic analysis of viral communities in enrichment cultures".
Environmental Microbiology
.
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(6): 2002?2014.
Bibcode
:
2019EnvMi..21.2002L
.
doi
:
10.1111/1462-2920.14479
.
PMID
30451355
.
S2CID
53950297
.
- ^
Prangishvili D, Krupovic M (2012).
"A new proposed taxon for double-stranded DNA viruses, the order "Ligamenvirales"
"
.
Arch Virol
.
157
(4): 791?795.
doi
:
10.1007/s00705-012-1229-7
.
PMID
22270758
.
- ^
a
b
Wang, Fengbin; Baquero, Diana P; Su, Zhangli; Osinski, Tomasz; Prangishvili, David; Egelman, Edward H; Krupovic, Mart (2020).
"Structure of a filamentous virus uncovers familial ties within the archaeal virosphere"
.
Virus Evolution
.
6
(1): veaa023.
doi
:
10.1093/ve/veaa023
.
PMC
7189273
.
PMID
32368353
.
- ^
Kasson, P; DiMaio, F; Yu, X; Lucas-Staat, S; Krupovic, M; Schouten, S; Prangishvili, D; Egelman, EH (2017).
"Model for a novel membrane envelope in a filamentous hyperthermophilic virus"
.
eLife
.
6
: e26268.
doi
:
10.7554/eLife.26268
.
PMC
5517147
.
PMID
28639939
.
- ^
Wang, F; Baquero, DP; Beltran, LC; Su, Z; Osinski, T; Zheng, W; Prangishvili, D; Krupovic, M; Egelman, EH (2020).
"Structures of filamentous viruses infecting hyperthermophilic archaea explain DNA stabilization in extreme environments"
.
Proceedings of the National Academy of Sciences of the United States of America
.
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:
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.
doi
:
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.
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7443925
.
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32759221
.
- ^
a
b
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.
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:
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.
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:
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.
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.
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.
External links
[
edit
]