Adaptations of fungi and fungal-like organisms for growth under reduced dissolved oxygen concentrations

Abstract

Our knowledge of the ecological roles of fungi in oxygen-depleted environments has been limited because of the lack of techniques for observing, isolating, and growing these fungi, and as a result they were thought to have only a minor role in the ecosystem processes of anoxic environments . Furthermore, only a few species of fungi have been tested for growth under anaerobic conditions in culture, and the redox potentials in oxygen depleted environments, where fungi have been found, have rarely been measured. Some of the species of fungi which will grow under anaerobic conditions are considered in this chapter. This chapter provides an overview on the diversity, metabolism, and ecological roles of fungi and fungal-like organisms that have adapted to host-associated as well as nonhost-associated anoxic environments. It focuses on true fungi and fungal-like organisms in the Opisthokont supergroup and in fungal-like organisms in the Oomycota (Rhizaria+Alveolates+Stramenopiles supergroup) and does not consider the protists in the other supergroups as defined by Baldauf (2003, 2008). In particular, the important ecological roles of these organisms are discussed.