INVESTIGATING THE ROLE OF E. COLI TCA CYCLE METABOLISM IN BACTERIOPHAGE REPLICATION

Abstract

Bacteriophages are viruses that specifically infect and hijack Escherichia coli's metabolic processes to proliferate, ultimately destroying the host cell in the process. The Tricarboxylic Acid Cycle (TCA Cycle) is a multi-step aerobic enzyme-catalyzed pathway that occurs in the cytoplasm of E. coli and is responsible for generating the electron-carrier molecules NADH and FADH2 which are crucial for generating ATP for the cell in future steps of cellular respiration. The E. coli genes, acnB, and acnA, encode enzymes that catalyze different reactions that are necessary for the TCA cycle.

We hypothesize that the removal of these genes would negatively impact the growth rate and ATP levels of E. coli and, as a result, inhibit or slow the replication of bacteriophage. To determine the effects of the removal of these genes, enzyme assays, comparative growth curves of the knockout strains, and plaque assays of bacteriophage replication were measured and investigated. Furthermore, we quantified the knockout’s effects by collecting lysis curves as well as performing an ATP assay using bioluminescence.