A proteolytic cleavage gives rise to the mature capsid vertex protein.
Belongs to the Tevenvirinae capsid vertex protein family.
Capsid protein that self-associates to form pentons, building the capsid in association with hexamers of the major capsid protein and one dodecamer of the portal protein.
Homopentamer. Interacts with the portal protein. Interacts with the major capsid protein that forms hexamers.
Accumulates harmlessly in the cytoplasmic membrane until it reaches a critical concentration that triggers the formation of micron-scale pores (holes) causing host cell membrane disruption and endolysin escape into the periplasmic space. Determines the precise timing of host cell lysis. Regulated by specific antiholins that somehow sense superinfections and then delay lysis. Participates with the endolysin and spanin proteins in the sequential events which lead to the programmed host cell lysis releasing the mature viral particles from the host cell.
Belongs to the T4likevirus holin family.
Disulfide bond is required for functionality.
Homomultimer. Heterotetramer composed of 2 holin and 2 antiholin. The holin-antiholin complex binds dsDNA. Interacts (via C-terminus) with antiholin (via C-terminus); this interaction blocks the holin homomultimerization and delays host cell lysis. Interacts (via N-terminus) with the lysis inhibition accessory protein rIII; this interaction stabilizes the holin-antiholin complex thereby resulting in a robust block of the hole formation.
The C-terminus serves, in association with the antiholin, as a DNA sensor for lysis inhibition under superinfection conditions.
Activation of anaerobic ribonucleoside-triphosphate reductase under anaerobic conditions by generation of an organic free radical, using S-adenosylmethionine and reduced flavodoxin as cosubstrates to produce 5'-deoxy-adenosine.
Belongs to the organic radical-activating enzymes family.
Belongs to the Caudovirales head completion nuclease family.
During phage morphogenesis, plays an essential role in the head-tail joining step. The associated nuclease activity is essential for morphogenesis, possibly by cleaving packaged DNA to enable the joining of heads to tails. Displays both exo- and endonuclease activity.
Belongs to the Tequatrovirus RNA ligase 1 family.
Binds 2 magnesium ions that perform the catalytic activity via a two-metal mechanism. One of the catalytic Mg(2+), which is coordinated by 5 water molecules, engages the lysine nucleophile and the ATP alpha phosphate while the Mg(2+) orients the PPi leaving group.
Involved in countering a host defense mechanism which, following viral infection, activates the host anticodon nuclease and shuts off viral translation. Repairs 5'-PO4 and 3'-OH groups in the cleaved host tRNA.
Belongs to the Tequatrovirus single-stranded DNA-binding protein family.
Homodimer in the absence of DNA, monomer when binding DNA. Interacts with the DNA helicase assembly protein; a ternary complex between the helicase assembly protein, the single-stranded DNA-binding protein and ssDNA is an obligatory intermediate in the helicase loading mechanism. Part of the replicase complex that includes the DNA polymerase, the polymerase clamp, the clamp loader complex, the single-stranded DNA binding protein, the primase, the DnaB-like SF4 replicative helicase and the helicase assembly factor. Interacts (via C-terminus) with the viral SF1 dDA helicase. Interacts with the viral SF2 UvsW repair helicase.
Single-stranded DNA-binding protein that participates in viral DNA replication, recombination, and repair. Coats the lagging-strand ssDNA as the replication fork advances. Stimulates the activities of viral DNA polymerase and DnaB-like SF4 replicative helicase, probably via its interaction with the helicase assembly factor. Together with DnaB-like SF4 replicative helicase and the helicase assembly factor, promotes pairing of two homologous DNA molecules containing complementary single-stranded regions and mediates homologous DNA strand exchange. Promotes also the formation of joint molecules. mRNA specific autogenous translational repressor.
The acidic C-terminus is involved in modulating the ssDNA binding properties. The N-terminus LAST motif is involved in the cooperative binding of the protein to ssDNA.
Belongs to the anti-CBASS protein Acb1 family.
Baseplate central spike complex-associated lysozyme that is essential for the localized hydrolysis of bacterial cell wall, so that the tail tube, through which the phage DNA is ejected, can penetrate to the host inner membrane. The tail lysozyme complex at the tip of the tail tube penetrates through the outer membrane into the periplasm and during that process, gp5* dissociates from gp5C and activated. Due to the lower pH in the periplasm, gp5* would dissociate from gp27 which probably still binds to the tip of the tube. This way, lysozyme domain is released and locally digests the peptidoglycan layer to make a hole to let the tube penetrate to the inner membrane. Involved in the tail assembly.
Belongs to the glycosyl hydrolase 24 family.
Homotrimer. The central spike complex, which creates an extension of the tail tube, is made up of three copies of the gp27-gp5*-gp5C complex and one copy of gp5.4. Part of the baseplate macromolecular complex which consists of gp5*, gp5C, gp5.4, gp27 (central spike complex); gp6, gp25, gp53 (inner baseplate); gp7, gp8 (intermediate baseplate); gp9, gp10, gp11, gp12 (peripheral); gp48 and gp54 (proximal region of the tail tube).
In the fully assembled virus, gp5 precursor is cleaved to form the mature tail lysozyme gp5*, and a C-terminus fragment, gp5C. The two fragments remain associated with the virion. The enzymatic activity of the precursor is about 10% of that of mature gp5*.
Monomer. The central spike complex, which creates an extension of the tail tube, is made up of three copies of the gp27-gp5*-gp5C complex and one copy of gp5.4. Part of the baseplate macromolecular complex which consists of gp5*, gp5C, gp5.4, gp27 (central spike complex); gp6, gp25, gp53 (inner baseplate); gp7, gp8 (intermediate baseplate); gp9, gp10, gp11, gp12 (peripheral); gp48 and gp54 (proximal region of the tail tube).
ADP-ribosyltransferase that efficiently ADP-ribosylates one of the two alpha subunits of host RNA polymerase RPOA on an arginine located in the C-terminal region. ADP-ribosylation of RPOA alpha subunit enhances the transcription of viral early genes. Also ribosylates RPOA subunits beta, beta' and sigma 70 and performs an autoribosylation reaction.
Belongs to the Tevenvirinae NAD(+)--arginine ADP-ribosyltransferase family.
Belongs to the DNA polymerase type-B family.
Part of the replicase complex that includes the DNA polymerase, the polymerase clamp, the clamp loader complex, the single-stranded DNA binding protein, and the primase/helicase. Interacts with the polymerase clamp; this interaction constitutes the polymerase holoenzyme.
Replicates the viral genomic DNA. This polymerase possesses two enzymatic activities: DNA synthesis (polymerase) and an exonucleolytic activity that degrades single-stranded DNA in the 3'- to 5'-direction for proofreading purpose.
The N-terminus contains the 3'-5' exonuclease activity. The C-terminus contains the polymerase activity and is involved in binding to the polymerase clamp protein. A beta hairpin structure is necessary for the proofreading function of the polymerase.
Activates transcription at late promoters when the sliding clamp is present. Binds to both the host RNA polymerase (RNAP) and the upstream dsDNA.
Belongs to the Tevenvirinae late transcription coactivator family.
Interacts with the beta subunit of host RNAP RpoB (via flap domain). Part of the transcription activation complex containing host RNAP, the viral RNA polymerase sigma-like factor, the coactivator gp33, and the sliding clamp.
The C-terminus is involved in transcriptional enhancement.
Belongs to the Tevenvirinae RNA polymerase sigma-like factor family.
Interacts with the host RNA polymerase catalytic core formed by RpoA, RpoB, RpoC and RpoZ to form the RNAP-gp55 holoenzyme. Part of the transcription activation complex containing host RNAP, the viral RNA polymerase sigma-like factor, the late transcription coactivator, and the sliding clamp. Interacts with the terminase large subunit; this interaction may load the terminase onto DNA for packaging.
Plays a role in the transcription of the viral late genes by acting as a late promoter recognition subunit. Associates with host RNA polymerase (RNAP) core and thus replaces the host sigma-70/rpoD subunit in the complex. May also play a role in DNA packaging by interacting with the terminase subunit gp17.
Belongs to the ribonucleoside diphosphate reductase small chain family.
Belongs to the Tevenvirinae sliding clamp family.
Homotrimer. Interacts with the viral DNA polymerase; this interaction constitutes the polymerase holoenzyme. Interacts with the sliding-clamp-loader; this interaction allows the sliding-clamp-loader to open the sliding clamp. Interacts with the viral DNA ligase. Part of the replicase complex that includes the DNA polymerase, the polymerase clamp, the clamp loader complex, the single-stranded DNA binding protein, the primase, the helicase and the helicase assembly factor. Interacts with the viral RNA polymerase (RNAP). Part of the transcription activation complex containing host RNAP, the viral RNA polymerase sigma-like factor, the late transcription coactivator, and the sliding clamp.
Sliding clamp that encircles the genomic DNA and links the DNA polymerase to the template to control the processivity of DNA synthesis. Responsible for tethering the catalytic subunit of DNA polymerase to DNA during high-speed replication. Interaction with the sliding-clamp-loader opens the sliding clamp so that it can be loaded around the DNA template. During transcription, encircles the DNA and tethers host RNA polymerase (RNAP) to it.
Belongs to the thymidylate synthase family.
ATPase activity requires 1 Mg(2+) ion per subunit. Nuclease activity probably requires 2 Mg(2+) ions per subunit.
Belongs to the Tequatrovirus large terminase family.
Interacts with the terminase small subunit; the active complex is composed of a pentamer of terminase large subunits and a dodecamer of terminase small subunits. Interacts with the portal protein.
Lacks conserved residue(s) required for the propagation of feature annotation.
Stimulated up to 50 to 100-fold by the terminase small subunit.
The N-terminus contains an ATPase domain. The C-terminus contains an endonuclease domain.
The terminase large subunit acts as an ATP driven molecular motor necessary for viral DNA translocation into empty capsids and as an endonuclease that cuts the viral genome to initiate and to end a packaging reaction. The terminase lies at a unique vertex of the procapsid and is composed of two subunits, a small terminase subunit involved in viral DNA recognition (packaging sequence), and a large terminase subunit possessing endonucleolytic and ATPase activities. Both terminase subunits heterooligomerize and are docked on the portal protein to form the packaging machine. The terminase large subunit exhibits endonuclease activity and cleaves the viral genome concatemer once the capsid is full (headful packaging). Once the capsid is packaged with the DNA, the terminase complex is substituted by the tail.
Belongs to the T4likevirus antiholin family.
Homotetramer; in free-form. Homomultimer. Heterotetramer composed of 2 holin and 2 antiholin. The holin-antiholin complex binds dsDNA. Interacts (via C-terminus) with holin (via C-terminus); this interaction blocks the holin homomultimerization and delays the host cell lysis.
Involved in lysis inhibition. Senses superinfections and inhibits the holin, thereby delaying the host cell lysis timing. The genomic DNA from the superinfecting phage bound to the complex holin-antiholin probably serves as a signal for the lysis inhibition and blocks the holin multimerization.
To endonucleases of group I introns of fungi and phage.
Belongs to the Tevenvirinae sliding-clamp-loader large subunit family.
Forms the sliding-clamp-loader together with the small subunit. Functions as an ATPase enzyme. The clamp loader holds the clamp in an open conformation and places it onto the DNA. 4 ATP molecules must bind to the sliding-clamp-loader before the latter can open the sliding clamp. ATP hydrolysis triggers the detachment of the sliding clamp from the sliding-clamp-loader, freeing the sliding clamp to track along DNA.
The sliding-clamp-loader consists of 4 large subunits and 1 small subunit. Interacts with the sliding clamp; this interaction allows the sliding-clamp-loader to open the sliding clamp. Part of the replicase complex that includes the DNA polymerase, the polymerase clamp, the clamp loader complex, the single-stranded DNA binding protein, the primase, the helicase and the helicase assembly factor.
ADP-ribosyltransferase that regulates transcription by ADP-ribosylation of host ribosomal protein S1 (PubMed:10634320). Additional identified targets include proteins involved in either translation or cellular metabolism such as elongation factor-Tu or trigger factor.
Belongs to the Tevenvirinae NAD--protein ADP-ribosyltransferase modA family.
Disorganizes the host nucleoid and inhibits replication, but without host DNA cleavage or degradation. Only the architecture of the nucleoid is affected. May act on the host chromosomal sequences that determine the structure of the nucleoid. Binds to dsDNA but not to ssDNA.
Belongs to the cytidine and deoxycytidylate deaminase family.
Controls the translation of a number of proteins (such as regA itself, rIIB and at least 35 others) by binding to their mRNA.
Capsid decoration protein which helps to stabilize the capsid against extremes of pH and temperature. Once maturation and expansion of the capsid has occured, trimers of soc attach the interfaces between the hexamer of the major capsid protein. Acts as a 'glue' between neighboring hexameric capsomers. Dispensable for the head morphogenesis and phage infection.
Homotrimer. Interacts with the major capsid protein; three soc molecules associate with each interface between the major capsid protein facets.
ADP-ribosyltransferase that efficiently ADP-ribosylates both alpha subunits of host RNA polymerase RPOA. The ModA-induced ADP-ribosylation of RPOA alpha subunits inhibits transcription from viral early promoters.
Belongs to the Tevenvirinae spackle protein family.
Inhibits viral DNA ejection into the host cytoplasm, thereby confering the infected host bacteria with immunity against secondary phage infection. Achieves superinfection exclusion by localizing to the periplasm and inhibiting the activity of tail-associated lysozyme, thereby preventing penetration by the tail tube of incoming phages.
Monomer. Interacts with the baseplate central spike protein; this interaction selectively inhibits the lysozyme activity of the baseplate central spike protein.
Belongs to the T4likevirus lysis inhibition accessory protein rIII family.
Homooligomer. Interacts with holin (via N-terminus).
Probably binds to the cytoplasmic part of the holin during lysis inhibition and stabilizes the holin-antiholin complex thereby resulting in a robust block of the hole formation.
Capsid decoration protein that binds as a monomer at the center of each major capsid protein hexamer once maturation and expension of the capsid has occured. It only has a marginal effect on head stability. Dispensable for the head morphogenesis and phage infection.
Monomer. Interacts with the major capsid protein; one hoc molecule associates with each hexamer facet.
Belongs to the Tevenvirinae portal protein family.
Forms the portal vertex of the capsid. This portal plays critical roles in head assembly, genome packaging, neck/tail attachment, and genome ejection. The portal protein multimerizes as a single ring-shaped homododecamer arranged around a central channel. Binds to the terminase subunits to form the packaging machine.
Homododecamer. Interacts with the large terminase subunit. Interacts with the major capsid protein. Interacts with the capsid vertex protein.
ATP-dependent DNA helicase essential for viral DNA replication and recombination. The helicase moves 5' -> 3' on the lagging strand template, unwinding the DNA duplex ahead of the leading strand polymerase at the replication fork and generating ssDNA for both leading and lagging strand synthesis. Interaction with the primase allows the primase to initiate lagging strand synthesis and fully activates the helicase. Loaded by the helicase assembly factor on replication forks that begin at discrete replication origin sequences, as well as on forks that are created during recombination.
Belongs to the helicase family. DnaB subfamily.
Homohexamer. The homohexamer is a trimer of asymmetric dimers. Interacts with the DNA primase; this interaction forms the active primosome complex, which is composed of 6 helicase and 1 primase subunits and expresses full helicase and primase activities. Interacts (via C-terminus) with the helicase assembly factor; this interaction brings about the rapid assembly of the helicase onto ssDNA. Part of the replicase complex that includes the DNA polymerase, the polymerase clamp, the clamp loader complex, the single-stranded DNA binding protein, the primase, the DnaB-like replicative helicase and the helicase assembly factor.
Belongs to the Tevenvirinae sliding-clamp-loader small subunit family.
Forms the sliding-clamp-loader together with the small subunit. The clamp loader holds the clamp in an open conformation and places it onto the DNA.