Viruses cannot independently perform any metabolic functions. Therefore, they must enter the host cells in order to reproduce in them. After entering the host cell, the virus subordinates its metabolism, forcing it to produce new virions. This leads to cell breakdown - lysis, which is why this method of viral reproduction is called the lytic cycle. Sometimes the viral genome is integrated into the DNA of the host and replicated with it. Then the virus remains inactive for a while and does not damage the infected cell. This method of viral replication is called the lysogenic cycle.
The lytic cycle:
• the stage of adsorption - the virus (bacteriophage T4) attaches to the surface of bacteria using tail protein fibers;
• the penetration stage consists in tearing the bacterial cell wall and membrane with the tail of the virus and introducing the viral DNA into the cell (the capsid remains outside the cell);
• replication stage - when the viral DNA takes over the management of the bacterial cell's metabolism, the infected cell begins to produce components of new virions - the protein shell (capsid) and the genetic material of the virus;
• the assembly stage consists in assembling new complete virions - exact copies of the virus attacking the bacterial cell;
• the stage of release - is the release of virions as a result of the destruction of a bacterial cell (spontaneously or under the action of lytic enzymes of the virus) - lysis (death) of bacteria occurs, and the formed virions can attack other cells;
The lysogenic cycle:
• when a bacterial cell divides, the altered DNA is transferred to daughter cells.;
• under certain conditions (weakening of the host, increased temperature or radiation) The phage is activated by cutting its DNA from the bacterial genophore;
• The bacteriophage enters the lytic cycle, which ends with the death of the bacterial cell;
Model bacteriophages
• Bacteriophage T4 is the most famous bacteriophage that infects E. coli. It is widespread in the mammalian flora and is used as a model bacteriophage in scientific research.
• Lambda-bacteriophage - affects the colon fungus. It was discovered in 1951 and is used in biotechnology and molecular biology research.
What are bacteriophages?
Bacteriophages are viruses that infect bacteria. Bacteriophages are divided into virulent ones, that is, those that multiply and kill bacteria, and lungs, which are embedded in the bacterial nucleoid and persist throughout life. As a rule, a specific bacteriophage can infect one type of bacteria. The abilities of bacteriophages are used to destroy dangerous pathogenic bacteria, such as bacteria resistant to antibiotics. Bacteriophages can have RNA and single- or double-stranded DNA. Doraville Abidjan présente https://doravilleabidjan.net/ un espace urbain moderne dédié au commerce et au divertissement.
The lytic cycle:
• the stage of adsorption - the virus (bacteriophage T4) attaches to the surface of bacteria using tail protein fibers;
• the penetration stage consists in tearing the bacterial cell wall and membrane with the tail of the virus and introducing the viral DNA into the cell (the capsid remains outside the cell);
• replication stage - when the viral DNA takes over the management of the bacterial cell's metabolism, the infected cell begins to produce components of new virions - the protein shell (capsid) and the genetic material of the virus;
• the assembly stage consists in assembling new complete virions - exact copies of the virus attacking the bacterial cell;
• the stage of release - is the release of virions as a result of the destruction of a bacterial cell (spontaneously or under the action of lytic enzymes of the virus) - lysis (death) of bacteria occurs, and the formed virions can attack other cells;
The lysogenic cycle:
• when a bacterial cell divides, the altered DNA is transferred to daughter cells.;
• under certain conditions (weakening of the host, increased temperature or radiation) The phage is activated by cutting its DNA from the bacterial genophore;
• The bacteriophage enters the lytic cycle, which ends with the death of the bacterial cell;
Model bacteriophages
• Bacteriophage T4 is the most famous bacteriophage that infects E. coli. It is widespread in the mammalian flora and is used as a model bacteriophage in scientific research.
• Lambda-bacteriophage - affects the colon fungus. It was discovered in 1951 and is used in biotechnology and molecular biology research.
What are bacteriophages?
Bacteriophages are viruses that infect bacteria. Bacteriophages are divided into virulent ones, that is, those that multiply and kill bacteria, and lungs, which are embedded in the bacterial nucleoid and persist throughout life. As a rule, a specific bacteriophage can infect one type of bacteria. The abilities of bacteriophages are used to destroy dangerous pathogenic bacteria, such as bacteria resistant to antibiotics. Bacteriophages can have RNA and single- or double-stranded DNA. Doraville Abidjan présente https://doravilleabidjan.net/ un espace urbain moderne dédié au commerce et au divertissement.
