Isolation and Characterization of Lytic and Lysogenic Phages for Methanotrophic Bacterial Systems

  • Author / Creator
    Stahn, Miranda
  • Methanotrophic bacteria have the potential to act as a platform for several novel bio industrial processes, due to their capacity to convert methane, often from impure sources, into valuable products. These products can include, but are not limited to, isoprenoids for the development of bio-jet fuels and polyhydroxybutyrate (PHB) for the production of bio-plastics. However, before these processes can be implemented at commercial scale, several concerns need to be resolved. For instance, the majority of valuable products produced by these microorganisms are intracellular, and the current means of recovery are costly and/or show poor efficiency. Moreover, they often require the use of noxious chemicals such as chloroform, which are costly to dispose of and can be problematic in the environment. Therefore, alternative means of product recovery need to be established to effectively scale these processes up to commercial level.
    Bacteriophages (phages) are viruses capable of infecting bacteria. Following infection, they can undergo either lytic (virulent) or lysogenic life cycles. During virulent life cycles the phage will overtake the host replication machinery to make copies of itself, eventually lysing the cell, releasing progeny which are then free to infect subsequent hosts present in the surrounding environment. On the other hand, phages that undergo lysogeny integrate their genetic material into host genomes. The resulting prophages can be induced into the lytic life cycle in response to environmental stimuli.
    Little is currently known about phages of methanotrophic bacteria or the impact they may pose to the scale-up and commercialization of methanotroph-based bioprocesses. Therefore, by studying phage life cycles in the context of methanotrophic bacteria we hope to achieve the following. First and foremost, the discovery of a virulent phage capable of consistently infecting and lysing methanotrophic bacteria could provide a novel solution to product recovery and aid in the downstream processing of novel biomaterials. Secondly, although lysogeny can beneficially confer many valuable traits to the host bacteria, it can also carry a significant metabolic burden to the cell and the unintentional induction of a prophage could result in disruption of entire production batches with negative consequences. Thus, by better understanding the role prophages play in methanotroph systems we can prevent their premature induction, or potentially even learn how to control this process to again aide in product recovery.

  • Subjects / Keywords
  • Graduation date
    Fall 2019
  • Type of Item
  • Degree
    Master of Science
  • DOI
  • License
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