Date of Award

Spring 2023

Document Type

Open Access Thesis


Marine Science

First Advisor

Xuefeng (Nick) Peng


Microbial metabolic activity is central to biogeochemical cycling in virtually all ecosystems. Fungi are important parts of microbial communities, serving as decomposers, parasites, and symbionts. Most of our understanding of fungal ecology is derived from the study of isolated, cultured terrestrial fungi. However, the marine environment includes thousands of divergent, uncultured fungi. A number of these species, which include saprobes, parasites, and endophytes, can survive and sporulate in a wide range of salinities. Other such species face the additional challenge of limited nutrient accessibility. The genus Exophiala includes agents of mycoses in both humans and in marine animals. This research seeks to characterize the genome of Exophiala sp. ETNP2018, a novel strain of marine fungi isolated from the Eastern Tropical North Pacific (ETNP) oxygen minimum zone, revealing the genetic adaptations of this strain to its unique environment, including low oxygen conditions and nutrient limitation. Structural and functional annotation, as well as a comparison to the representative species of its genus (Exophiala aquamarina), serves to elucidate the lifestyle of this novel strain. Furthermore, this research will, through the identification of protein-encoding sequences, determine the mechanisms used by this species to break down and metabolize biomass in the ocean.


© 2023, Margaret Kelly Bernish