Cell death due to excess GTP and phage activation in B. subtilis

Session Number

Project ID: BIO 43

Advisor(s)

Dr. Kachun (Danny) Fung; University of Wisconsin

Dr. Jade Wang; University of Wisconsin

Discipline

Biology

Start Date

22-4-2020 9:45 AM

End Date

22-4-2020 10:00 AM

Abstract

Guanosine penta/tetraphosphate ((p)ppGpp) is involved with the stringent response in bacteria, and it inhibits RNA synthesis when there is a shortage of amino acids by regulating Guanosine triphosphate (GTP) biosynthesis enzymes. Due to unknown reasons, excess GTP has been observed to kill cells due to a lack of the alarmone nucleotide (p)ppGpp in Bacillus subtilis. The aim of this study was to research the link between GTP and phage activation. GTP is the energy used for transcription and replication. Due to the extremely high rate that these two processes happen in a cell, these processes may meet one another and cause damage to the DNA. It was hypothesized that increased GTP leads to DNA damage through transcription-replication conflict, which causes phage activation and kills the cells. Cells without (p)ppGpp were grown with or without phages, with or without pcrA overexpression (a gene that reduces transcription-replication conflict), and with or without a vector control. The results of this study found that cells grown in the absence of (p)ppGpp without phages had much higher populations than those grown with phages. It was also found that overexpression of pcrA in cells with phages was able to prevent some, but not all, cell death.

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Apr 22nd, 9:45 AM Apr 22nd, 10:00 AM

Cell death due to excess GTP and phage activation in B. subtilis

Guanosine penta/tetraphosphate ((p)ppGpp) is involved with the stringent response in bacteria, and it inhibits RNA synthesis when there is a shortage of amino acids by regulating Guanosine triphosphate (GTP) biosynthesis enzymes. Due to unknown reasons, excess GTP has been observed to kill cells due to a lack of the alarmone nucleotide (p)ppGpp in Bacillus subtilis. The aim of this study was to research the link between GTP and phage activation. GTP is the energy used for transcription and replication. Due to the extremely high rate that these two processes happen in a cell, these processes may meet one another and cause damage to the DNA. It was hypothesized that increased GTP leads to DNA damage through transcription-replication conflict, which causes phage activation and kills the cells. Cells without (p)ppGpp were grown with or without phages, with or without pcrA overexpression (a gene that reduces transcription-replication conflict), and with or without a vector control. The results of this study found that cells grown in the absence of (p)ppGpp without phages had much higher populations than those grown with phages. It was also found that overexpression of pcrA in cells with phages was able to prevent some, but not all, cell death.