Multiple Choice
A mixed infection of two bacteriophage strains is often used for what purpose?
407
views
5. Genetics of Bacteria and Viruses
Bacteriophage Genetics
2:57 minutesProblem 2
Textbook Question
Write a short summary that contrasts how recombination occurs in bacteria and bacteriophages.
Verified step by step guidance1
Understand that recombination refers to the exchange of genetic material between different DNA molecules, which can occur in both bacteria and bacteriophages, but through distinct mechanisms.
In bacteria, recombination typically occurs through processes such as transformation (uptake of foreign DNA from the environment), conjugation (direct transfer of DNA between two bacterial cells via a pilus), and transduction (transfer of DNA mediated by a bacteriophage).
In bacteriophages, recombination occurs during their replication cycle, particularly in the lysogenic cycle, where the phage DNA integrates into the host bacterial genome and can later excise, sometimes carrying bacterial genes with it. This is known as specialized transduction.
Contrast the mechanisms: In bacteria, recombination often involves direct DNA exchange between cells or uptake from the environment, while in bacteriophages, recombination is mediated by the phage's lifecycle and its interaction with the host genome.
Summarize the key difference: Bacterial recombination is primarily a horizontal gene transfer process between cells, whereas bacteriophage recombination involves the integration and excision of phage DNA within a host genome, sometimes leading to gene transfer between bacteria.
Verified video answer for a similar problem:This video solution was recommended by our tutors as helpful for the problem above
Video duration:
2mWas this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Recombination in Bacteria
Recombination in bacteria primarily occurs through three mechanisms: transformation, transduction, and conjugation. Transformation involves the uptake of free DNA from the environment, while transduction is mediated by bacteriophages that transfer genetic material between bacterial cells. Conjugation requires direct cell-to-cell contact, allowing the transfer of plasmids or chromosomal DNA, facilitating genetic diversity and adaptation.
Recommended video:
Guided course
03:51
Recombination after Single Strand Breaks
Recombination in Bacteriophages
Bacteriophages, or phages, can undergo recombination through processes such as generalized and specialized transduction. In generalized transduction, any bacterial gene can be transferred when a phage mistakenly packages bacterial DNA during replication. Specialized transduction occurs when a phage integrates into the bacterial genome and, upon excision, carries adjacent bacterial genes, leading to the transfer of specific traits between bacteria.
Recommended video:
Guided course
06:04Mapping Bacteriophages
Genetic Diversity and Evolution
Both bacterial and phage recombination contribute significantly to genetic diversity and evolution. In bacteria, recombination allows for the rapid acquisition of new traits, such as antibiotic resistance, enhancing survival in changing environments. For bacteriophages, recombination facilitates the adaptation of phages to their bacterial hosts, influencing the dynamics of bacterial populations and the co-evolutionary arms race between bacteria and phages.
Recommended video:
Guided course
08:22Evolution
3:44mWatch next
Master Plaques and Experiments with a bite sized video explanation from Kylia
Start learningRelated Videos
Related Practice