Mountain View
biomedical and healthCAre Data Discovery Index Ecosystem
help Advanced Search
Title: Podoviridae      
ID:
PRJNA16856
description:
Description of Podoviridae adapted from ICTVdb Virion Properties Morphology Phages consist of a head and a tail and are not enveloped. Phage has a head with icosahedral symmetry and a tail with helical symmetry and exhibits icosahedral symmetry (T=7). The head is isometric and has a diameter of 60 nm. Head appear hexagonal in outline and consists of 72 capsomers. The tail is straight, short and thick, non-contractile rod built of stacked disks that is not banded and has a length of 17 nm and a width of 6 nm. The tail has 6 short, subterminal fibers. Physicochemical and Physical Properties The molecular mass (Mr) of virions is about 48 x 106. Virions have a buoyant density in CsCl of 1.44-1.51 g cm-3. The sedimentation coefficient is 510 S20w. Virions are not sensitive to treatment with ether and chloroform. Nucleic Acid The Mr of the genome constitutes 50% of the virion by weight. The genome is not segmented and contains a single molecule of linear double-stranded DNA. The DNA is fully sequenced. Complete sequence is 40000-42000 nucleotides long. The genome has a guanine + cytosine content of 50 %. Double stranded DNA is non-permuted. The genome has terminally redundant sequences. Proteins Proteins constitute about 50% of the particle weight. The viral genome encodes structural proteins and non-structural proteins. Virions consist of at least 9 structural protein(s) located in the capsid. Structural Proteins: Capsid protein head protein. Capsid protein has a molecular mass of 38000 Da with 460 copies per virion. Non-Structural Proteins: In addition to the polymerase, the virus codes for enzymes such as adenylated transferase (B type DNA polymerase and RNA polymerase) and 3 internal protein(s) located inside the head. Lipids Lipids are not reported. Carbohydrates Carbohydrates have not been reported. Genome Organization and Replication Phages are adsorbed tail first to specific receptors located on the cell wall and enter host cells by digestion with lysozyme. The process of intracellular uncoating of virions is understood. Virus uncoating occurs in the cytoplasm. Infection and Replication: Although severity of illness depends on route and dose, the majority of infections are virulent. Viral DNA entering the nucleus remains linear. Infecting genome integrates into the host genome. The host chromosome; degenerates. Transcription: The virus codes for about 55 gene(s). Virus transcription is temporally regulated; 2 classes of genes recognized; they are termed early and late. Genes with related functions are clustered together. Translation: Genome replication is bidirectional. During bidirectional replication transcription phase DNA forms concatamers. Genome replication occurs by a semi-conservative. Replication cycle Viral proteins accumulate in the cytoplasm; are associated with the perinuclear space (periphery of nucleoplasm). Virions accumulate in the cell cytoplasm. Assembly and Egress: Head proteins assemble with the viral DNA inside after genome has been cut into size to form the provirions (preformed capsids). Viruses assemble in the perinuclear space. Maturation: In thin sections the mature virus is can be seen in crystalline arrays. Release: Virus is released from host cell upon death by lysis.
accesstypes:
download
landingpage: http://www.ncbi.nlm.nih.gov/bioproject/PRJNA16856
authentication:
none
authorization:
none
abbreviation:
NCBI
homePage: http://www.ncbi.nlm.nih.gov
ID:
SCR:006472
name:
National Center for Biotechnology Information
homePage: http://www.ncbi.nlm.nih.gov/bioproject
ID:
SCR:004801
name:
NCBI BioProject