Abstract
Lyme disease is the most common vector borne disease in the U.S becoming more frequent where recently the CDC estimated 476,000 cases each year based on insurance records. It is caused by the bacterium Borrelia burgdorferi which is transmitted by lxodes scapularis and lxodes pacificus across the United States. As B. burgdorferi cycles between tick to host, it encounters numerous environmental changes such as shifts in pH, organic acids, and osmolarity levels. B. burgdorferi successfully adapts to these environmental cues through changes in gene expression carried out by RNA polymerase (RNAP). The RNAP holoenzyme consists of two ɑ subunits, a β subunit, and a β’ subunit. Additional proteins have been implicated in the function of RNAP including RpoZ (i.e. omega subunit, ω). Investigations of RpoZ homologues from other bacteria have suggested the omega subunit helps stabilize the RNAP holoenzyme, help the RNAP bind to ? subunit during gene transcription, and bind to ppGpp to react to environmental stress. Open reading frame bb0820 of the B. burgdorferi genome is annotated as rpoZ, however, its function has yet to be tested. The goal of this study was to determine the functional role of RpoZ in B. burgdorferi. This is significant because RpoZ likely plays a critical role in the ability of B. burgdorferi to complete its infectious cycle and cause Lyme disease. My overarching hypothesis is that RpoZ contributes to B. burgdorferi gene expression, growth, survival, and infectivity.