Lysogeny is a fascinating phenomenon that is not commonly studied in schools. This is unfortunate because helping students understand lysogeny is essential to grasping the biology of microorganisms. Educators must emphasize lysogeny’s significance, as it can have a vast impact on the microbial communities and environments with which we interact. Hence, teaching students about how lysogeny works would prove useful in several fields, including medicine, microbiology, and ecology.
Lysogeny is a type of symbiotic relationship between viruses and bacteria that is frequently ignored in science education. In this process, the virus, called a temperate phage or bacteriophage, infects the bacterial cell. Instead of replicating and breaking open the host cell, as occurs in the lytic cycle, the temperate phage exists in a dormant state in the host chromosome as an integrated piece of DNA called a prophage. During this state, the viral genes become a heritable part of the host genome and are replicated along with the host’s DNA. The prophage can remain silent for thousands of generations of bacterial cell division, and these bacteria are called lysogenic bacteria.
When external circumstances favor the release of viruses from lysogenic bacteria, for instance, when the bacterium undergoes cellular stress, the prophage undergoes induction to produce many copies of itself, leading to phage replication and ultimately the death of the bacterium, as occurs in the lytic cycle.
The importance of lysogeny is underscored by the many factors that can lead viruses to become prophages. Scientists realize that prophages play a critical role in transferring genes between bacterial hosts, allowing the exchange of adaptability, as well as virulence factors, antibiotic resistance genes, and pathogenicity islands. The ability to transfer heritable genetic material from one bacterium to another is referred to as horizontal gene transfer. The formation and removal of lysogenic bacteria are responsible for the dynamics of gene flow in microbial communities. For instance, lysogeny is responsible for the transfer of the cholera toxin genes from a virulent strain to a non-pathogenic strain in the 1960s, leading to the emergence of a new and more virulent strain that sickened thousands in Bangladesh.
In addition to gene transfer, lysogeny has a significant influence on bacteriophages’ population dynamics and evolution. Environmental factors, such as the availability of nutrients and bacterial strain diversity, can selectively favor either lysogenic or lytic bacteriophage populations. By deciphering lysogeny’s effects, students can develop a new insight into bacteriophage biology and evolution over a broad timescale.
Teaching students about lysogeny can also have a practical application in many fields, including medicine, microbiology, and ecology. For instance, the mechanisms of lysogenic conversion, where prophage genes influence a bacterial host’s behavior, are of interest in understanding bacterial pathogenesis and immunity. Phage therapy is a growing area of interest in using bacteriophages as antimicrobial agents against antibiotic-resistant bacteria, and lysogeny has a significant role in the selection and evolution of the viruses used in phage therapy. Finally, lysogeny can be used as a tool in environmental microbiology to identify how phages function within ecosystems and how they influence microbial community dynamics.
In conclusion, lysogeny is an essential concept that students should learn in science education. Lysogeny has practical relevance in many fields and allows students to gain a deep insight into microbiology, genetics, and evolution. If students learn how lysogenic bacteria function, they will have a more comprehensive understanding of the interactions between bacteria and viruses and how they influence genetic and ecological variability. Therefore, it is imperative to include lysogeny in the science curriculum to prepare students for the emerging opportunities and challenges in microbiology, medicine, and ecological studies.
