Editing Lytic cycle (section)

== Transcription and biosynthesis ==
During the transcription and biosynthesis stages, the virus hijacks the cell's replication and translation mechanisms, using them to make more viruses. The virus's nucleic acid uses the host cell's metabolic machinery to make large amounts of viral components.<ref>{{cite web |title=Ebola - Lytic or Lysogenic |url=https://blog.ebola-cases.com/ebola-lytic-or-lysogenic/ |website=Ebola-Cases.com |access-date=2023-01-26}}</ref>

In DNA viruses, the DNA [[Transcription (genetics)|transcribes]] itself into [[messenger RNA]] (mRNA) molecules that are then used to direct the cell's ribosomes. One of the first polypeptides to be translated destroys the host's DNA. In [[retrovirus]]es (which inject an RNA strand), the enzyme [[reverse transcriptase]] transcribes the viral RNA into DNA, which is then transcribed again into RNA. Once the viral DNA has taken control it induces the host cell's machinery to synthesize viral DNA and proteins and begins to multiply.{{cn|date=October 2022}}

The biosynthesis is (e.g. [[Enterobacteria phage T4|T4]]) regulated in three phases of mRNA production followed by a phase of protein production.<ref name=Brock>{{cite book |editor1-last=Madigan |editor1-first=Michael T. |editor2-last=Martinko |editor2-first=John M. |title=Brock biology of microorganisms |date=2006 |publisher=Prentice Hall |isbn=978-0-13-144329-7 |edition=11}}</ref>

;Early phase
:Enzymes modify the host's transcriptional process by [[RNA polymerase]]. Amongst other modifications, virus T4 changes the [[sigma factor]] of the host by producing an [[anti-sigma factor]] so that the host [[promoter (biology)|promotor]]s are not recognized any more but now recognize T4 middle proteins. For protein synthesis [[Shine-Dalgarno]] subsequence GAGG dominates an early genes translation.<ref>{{cite journal |last1=Malys |first1=N |title=Shine-Dalgarno sequence of bacteriophage T4: GAGG prevails in early genes |journal=Molecular Biology Reports |volume=39 |issue=1 |pages=33–9 |year=2012 |pmid=21533668 |doi=10.1007/s11033-011-0707-4|s2cid=17854788 }}</ref>

;Middle phase
:Virus nucleic acid (DNA or RNA depending on virus type).{{cn|date=October 2022}}

;Late phase
:Structural proteins including those for the head and the tail.{{cn|date=October 2022}}