λ is a temperate bacteriophage, that means that it can interchangeably choose between any of two lifecycle strategies lysogeny or lysis. Through our reaserch, we observed how the bacteriophage adapts to changes in nutrients availability and temperature, and how the presence of the bacteriophage affects its host. The basic culture parameters were tested in batches and later with the help of one- and two-stage miniature chemostat bioreactor systems with E. coli. We characterized the host and revitalized the lyophilized bacteriophage, determined the specificity of culture growth and checked the activity of the bacteriophage. Statistical and graphical analysis of the data was performed and the growth parameters of the host identified. The effect of temperature on the bacteriophage and the host was tested in a series of batch experiments at different temperatures. The increase in temperature in the tested area had a positive effect on bacterial culture growth, bacteriophage growth was proportional to host growth, μmax was much slower compared to experiments where bacteriophage was not added to the system. Research of the limiting factors of switching between the two cycles was performed by restricting the flow of nutrients through the system. We found that temperature change has a much greater impact on host growth than flow regulation and consequently a greater impact on bacteriophage growth. In order to create a reliable predictive model for the switching of the reproductive cycle, many more successful experiments would need to be performed.
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