Dendryphiella salina and Debaryomyces hansenii: models for ecophysical adaptation to salinity by fungi that grow in the sea

Abstract

The physiology of adaptation to life in the marine environment is reviewed in two species of marine fungus, Dendryphiella salina, a filamentous Hyphomycete and Debaryomyces hansenii, an Ascomycete yeast. The constraints of living in an environment of highly negative water potential are assessed in terms of the overall water relations of these fungi and how osmotic potential is generated within the mycelium. The relative contribution of ionic and organic solutes to the osmotic potential, and how these compounds are compartmentalized within the hyphal cell, are discussed, together with what is known about how the processes leading to the generation of internal osmotic potential are regulated by the fungus. Key words: Dendryphiella salina, Debaryomyces hansenii, marine fungi, adaptation, osmotic potential, polyols.