Morphological response to salinity, temperature, and pH changes by marine fungus Epicoccum nigrum

Ramón Ahumada-Rudolph, Vanessa Novoa, José Becerra

Keywords: Fungal ecology, Extremophile fungi, Metabolism, Extracellular polymeric substance (EPS), Cell wall


Epicoccum nigrum (strain LQRA39-P) was isolated from sediments collected in Chilean Patagonian fjords using microscopy and molecular techniques. We analyzed adaptive responses of cell wall morphology to salinity, temperature, and pH in order to explain the ability of E. nigrum to co-inhabit both marine and freshwater environments. For this purpose, E. nigrum was cultured in a series of media with variations in salinity (freshwater and seawater), pH (acidic, neutral, and basic), and temperature (5 to 25 °C). Changes were observed through transmission electron microscopy. A direct correlation between increased salinity and cell wall thickening (> 0.2 μm) was observed, along with a significant relationship between pH and the presence of extracellular polymeric substances (EPS) on the outside of the cell wall. The observed morphological changes could confirm that an ubiquitous fungus such as E. nigrum requires adaptive responses to co-inhabit freshwater, marine, and terrestrial substrates.

Más información

Título de la Revista: Environmental Monitoring and Assessment
Volumen: 191
Número: 35
Editorial: Springer International Publishing
Fecha de publicación: 2019
Idioma: English
Notas: collection ISI