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ICTVdB Virus Description - 00.026. Flaviviridae

Descriptions are generated automatically from the ICTVdB database including links. Some descriptions are only very basic and links may point to documents that are not yet published on the Web.

Cite this publication as: ICTVdB Management (2006). 00.026. Flaviviridae. In: ICTVdB - The Universal Virus Database, version 3. Büchen-Osmond, C. (Ed), Columbia University, New York, USA

Cite this site as: ICTVdB - The Universal Virus Database, version 4. http://www.ncbi.nlm.nih.gov/ICTVdb/ICTVdB/

Classification

This is a description of a vertebrate virus at the family level.

ICTVdB Virus Code: 00.026. Virus accession number: 00026FAM. Obsolete virus code: 26.; superceded accession number: 26000000.
NCBI Taxon Identifier NCBI Taxonomy ID: 11050.

Name, Synonyms and Lineage

Synonym(s): Flavivirus group.

Morphology

Virions consist of an envelope and a nucleocapsid. Virus capsid is enveloped. Virions are spherical to pleomorphic measuring 40-60 nm in diameter. Surface projections are small spikes surrounded by a prominent fringe. Capsid/nucleocapsid is round and exhibits polyhedral symmetry. The core is isometric and has a diameter of 25-30 nm.

Capsids can be penetrated by stain and some appear dark in the center.

Physicochemical and Physical Properties

The molecular mass (Mr) of virions is 60 x 10⁶. Virions have a buoyant density in CsCl of 1.07-1.24 g cm^-3; sucrose of 1.1-1.23 g cm^-3. The sedimentation coefficient is 140-200 S_20w. Under in vitro conditions virions are stable in alkaline environment of pH 8. Virions are sensitive to treatment with heat, organic solvents, and detergents.

Nucleic Acid

The genome is not segmented and contains a single molecule of linear positive-sense, single-stranded RNA. The complete genome is 9500-12500 nucleotides long. The 5'-end of the genome has a methylated nucleotide cap, or genome-linked protein (VPg). The 3'-terminus has no poly (A) tract, or a poly (A) tract (in some strains of tick-borne encephalitis complex of flaviviruses).

GenBank records for nucleotide sequences; complete genome sequences.

Proteins

The viral genome encodes structural proteins and non-structural proteins. Virions consist of 3-4 structural protein(s).

Lipids

Lipids are present and located in the envelope. Virions are composed of 15-20% lipids by weight. The composition of viral lipids and host cell membranes are similar. The lipids are of host origin that derived from host cell membranes.

Genome Organization and Replication

By itself, genomic nucleic acid is infectious.

Replication cycle Features: the genome has 5' end encodes structural proteins which has a stem and loop structure. The non-structural proteins including protease, helicase and polymerase, are encode at the 3' end.