Vibrio cholerae is a natural inhabitant of aquatic environments and serves as the etiological agent for the severe diarrheal disease, cholera. Cholera epidemics follow a regular seasonal pattern, which account for tens to hundreds of thousands of deaths in a given year. V. choleraenaturally persist between epidemics through entry into a dormant state known as viable but nonculturable (VBNC). Research has shown that V. choleraein this VBNC state experience drastic morphological and metabolic changes, which serve as survival mechanisms until environmental conditions become suitable again. The natural marine ecosystem that V. cholerae inhabitis comprised of a complex combination of biotic and abiotic factors, which influence their growth and survival. Some of these factors include interactions with other marine dwellers and environmental pressures, such as fluctuations in temperature and oxygen concentration. Of great interest, we have currently elucidated the role of oxygen on the classical O395 biotype of V. cholerae. Through this discovery, we are especially interested in the role of oxygen and biotype on V. cholerae persistence and how these variables can influence entry into the VBNC dormant state. Specifically, in this study we will compare culturability between the O395 and N16961 biotypes in both aeration and static (non-aeration environments) at 4°C and 30°C. It is of crucial importance to elucidate the role of abiotic environmental factors involved with entry into this dormant state and to understand how V. cholerae have evolved their genetic mechanisms to persist in their natural environments through comparison of biotypes. Understanding entry into the VBNC state is significant because V. cholerae found in this dormant state remain a threat to the human population due their ability to resuscitate and infect the human host under the appropriate environmental conditions.
Bachelor of Science (B.S.)
College of Medicine
Freiberg, Amy M., "Elucidating the Role of Oxygen and Biotype in the Environmental Persistence of Vibrio Cholerae" (2019). Honors Undergraduate Theses. 664.