How does mitomycin C induce the lytic cycle?
Based on studies in the phage lambda (Gottesman & Oppenheim 1994), mitomycin C and UV-C damage the DNA, which activates the SOS repair system, including the enzyme RecA. The RecA protein cleaves a repressor and induces the lytic cycle.
How do you induce prophage?
The traditional and most common approach to studying prophages or temperate phages is to induce lysogenic bacteria with mitomycin C treatment or UV exposure (2, 18, 34). In most cases, bacteria isolated from environmental sources are induced without prior knowledge of the presence or absence of a prophage(s).
What is phage induction?
The process by which phage production is activated in a lysogen is known as induction. The purpose of this experiment is to use the temperate bacteriophage λ to create and isolate lysogens of E. coli, then to induce lytic cycle replication within those cells by exposing them to uv light.
What is Lysogenic conversion?
Lysogenic conversion describes the situation where a bacterial host acquires a new trait as a direct result of the expression a gene encoded by a lysogen. From: Encyclopedia of Virology (Fourth Edition), 2021.
Why is lysogeny advantageous to a bacteriophage?
Why is lysogeny advantageous to a bacteriophage? it speeds up the viral infection cycle. it allows the bacteriophage to destroy the host cell’s DNA.
What causes phage induction?
Lysogenic phage induction is usually a consequence of DNA damage (induced by UV light, mitomycin C, or similar mutagens); however, in all cases, it results from the destruction or inactivation of the phage repressor.
What are some factors that lead to phage induction?
Lytic production of phage particles is induced under stress conditions, such as DNA damage. Phages encode various virulence factors, such as Shiga toxins of enterohaemorrhagic Escherichia coli (EHEC). Moreover, prophages are also prevalent in bacteria associated with the human gut microbiome.
What phage protein is required for induction?
In bacteriophage lambda (λ), induction is associated with cleavage of the CI repressor. The result is production of the protein, Cro, which inhibits further production of CI.
What is lysogenic induction?
What is the difference between transduction and lysogenic conversion?
lysogenic cycle: A form of viral reproduction involving the fusion of the nucleic acid of a bacteriophage with that of a host, followed by proliferation of the resulting prophage. transduction: Transduction is the process by which DNA is transferred from one bacterium to another by a virus.
What is the mechanism of action of mitomycin C?
Alkylation of DNA is the most favored mechanism of action for MMC, but other modes of action, such as redox cycling and inhibition of rRNA, may also contribute to the biological action of the drug. In this work, we show that thioredoxin reductase (TrxR) is also a cellular target for MMC.
What triggers lysogeny?
Triggers that lead to a switch from lysogeny to lysis may include environmental damage to the host or its genome or, conversely, a peak in host growth and fitness that provides optimal conditions for viral replication and eventual lysis.
What is lysogeny in bacteriophage?
Lysogeny is characterized by integration of the bacteriophage nucleic acid into the host bacterium’s genome or formation of a circular replicon in the bacterial cytoplasm. In this condition the bacterium continues to live and reproduce normally, while the bacteriophage lies in a dormant state in the host cell.
What phage protein is necessary to maintain a stable lysogen?
Two phage proteins, Int and CI, are required to form stable lysogens. Int allows the integration of the phage genome into the bacterial chromosome, and CI represses the two early phage promoters to prevent any lytic phage gene expression.
What causes lysogenic induction?
What is the difference between lytic and lysogenic bacteriophages?
1: Lytic versus lysogenic cycle: A temperate bacteriophage has both lytic and lysogenic cycles. In the lytic cycle, the phage replicates and lyses the host cell. In the lysogenic cycle, phage DNA is incorporated into the host genome, where it is passed on to subsequent generations.