5 research outputs found
Cellular responses of microcolonial rock fungi to long-term desiccation and subsequent rehydration
Melanised rock-inhabiting fungi are astonishingly resistant to
environmental stresses. Also known as micro-colonial fungi (MCF), they are
ubiquitous and even colonise bare rocks in deserts. To survive in nutrient
poor and extremely stressful conditions, MCF have reduced morphogenetic
complexity to a minimum, and rely on a broad spectrum of stress protection
mechanisms. Although visual signs of carotenoid presence are masked by heavily
melanised black cell-walls, we were able to isolate and characterise a variety
of carotenoids (ß-carotene, ζ-carotene, phytoene, torularhodin and
torulene) in the rock-inhabiting, relatively fast-growing strain A95. The
desiccation/rehydration stress response was used to measure the ability of A95
to adapt to slow or fast changes in external conditions. Revival of MCF after
prolonged desiccation and rehydration was documented by biochemical (analyses
of lipids and protective pigments), cultivation, and microscopic methods.
Survival of MCF is enhanced when desiccation is rapid and mycostasis is
instant rather than following prolonged periods of low metabolic activity