New Scholar Award in Global Infectious Disease
Fitnat Yildiz, Ph.D.
University of California - Santa Cruz

Environmental factors that modulate biofilm formation dynamics in Vibrio cholerae O1 E1 Tor

Alterations to aquatic environments via natural or anthropogenic factors can directly or indirectly lead to infectious disease outbreaks. At present, little information is available on the molecular ecology and evolutionary dynamics of infectious agents in the environment. Understanding environmental factors involved in persistence, growth, and transmission of pathogens and the response of organisms to environmental changes will provide information about the emergence or re-emergence of infectious diseases.

Vibrio cholerae, the causative agent of the Asiatic cholera, is an excellent model system to study these processes because V. cholerae causes periodic seasonal outbreaks in regions where it is an established member of the indigenous aquatic flora. The capacity of the organism to cause seasonal epidemics is linked to its survival in free-living and in biofilm growth modes in aquatic environments between outbreaks. However, the processes governing the survival of V. cholerae and its adaptability to changes in habitat remain elusive.

In aquatic habitats V. cholerae is found as attached to various biotic and abiotic surfaces. It has been proposed that attachment of bacteria to surfaces, and subsequent biofilm growth mode, exemplifies a survival strategy. Identification of the genes required for the development of V. cholerae biofilms and of metabolic pathways operating in these biofilms is central to understanding of the sessile lifecycle of the organism. We know very little about the processes that allow V. cholerae to sense, respond, and adapt to a life on a surface. This project focuses on the identification and characterization of the signals and regulatory networks that are essential for biofilm formation by V. cholerae by employing the combined use of molecular genetics, functional genomics, proteomics, microbial ecology and microscopy.

Results will expand our understanding of the environmental life cycle of an important human pathogen and provide information useful for the prediction and control of cholera epidemics.

Contact Dr. Yildiz.