Exploration of Genome Length, Burst Time, and Burst Size of  Streptomyces griseus Bacteriophages (open access)

Exploration of Genome Length, Burst Time, and Burst Size of Streptomyces griseus Bacteriophages

Since phages use the host resources to replicate themselves after infection, the different sizes of the phage genome should influence the replication rate. We, therefore, hypothesized that the smaller genomes should burst the cell faster than the larger ones. As well, the shorter genomes would have greater burst sizes because they should replicate faster. Here, we obtained 16 phages of various genome length. All phages were isolated on Streptomyces griseus and available in our phage bank at the University of North Texas. We performed one-step growth studies for the 16 phages, as well as determined the host doubling time from its growth curve. The results show that S. griseus grown in nutrient broth has a doubling time of 5 hours and 22 minutes. This doubling time is used as a guideline for the phage growth studies. Because the filamentous nature of the host caused several difficulties during the experiment, we isolated single cells by sonication and centrifugation. After the cell number was determined by viable cell count, the cells were infected with each type of phage using a multiplicity of infection (MOI) of 0.5. The results show that phages' burst times range between 45 (±0, standard error) and 420 (±30) …
Date: May 2019
Creator: Maneekul, Jindanuch
System: The UNT Digital Library