Malassezia fungi have been linked to skin diseases like dandruff and eczema. Until recently, they were assumed to have evolved to inhabit mammalian skin. More recently, however, they have been found in a much wider range of habitats, and this short review focuses on what researchers know and would like to know about marine Malassezia.
Discoveries of Malassezia representatives in fish, plankton, sponges, corals, lobster, etc., and the fact that marine Malassezia appear to dominate certain marine habitats, suggest that marine Malassezia should be the focus of future research into the diversity and distribution of this enigmatic group. The paper also discusses the challenges of such research: Malassezia fungi are notoriously difficult to grow in laboratory cultures, especially in “clean” cultures that consist only of a single species, and recreating marine environments with specialized pressure and saltiness are likely to further complicate cultivation efforts.
From Dandruff to Deep-Sea Vents: Malassezia-like Fungi Are Ecologically Hyper-diverse. (2014) PLoS Pathog 10(8): e1004277. doi: 10.1371/ journal.ppat.1004277
As the dominant component of the mycobiota on human skin – both healthy and diseased – the genus Malassezia has received a fair amount of attention. Since the middle of the 19th century, researchers have linked these fungi with skin maladies such as dandruff and eczema, but their difficulty to culture axenically long hampered studies of their systematics and diversity. Malassezia is the sole genus within the fungal order Malasseziales, contained within the proposed subphylum Malasseziomycetes (anonymous reviewer; personal communication). Although Malassezia is sister to the so-called ”smut” plant pathogens, they are markedly divergent in ecological terms. A hallmark of Malassezia species is their incomplete fatty acids synthesis metabolic pathway, and reliance, instead, on a suite of extracellular lipases, phospho-lipases, and acid sphingomyelinases. In fact, only a single species, M. pachydermatis, is able to survive in culture. Until recently, it was assumed that Malassezia evolved into a specialized and narrow niche associated with the skin of mammalian hosts. However, culture-independent studies of fungi from environmental samples show that Malassezia are exceedingly widespread and ecologically diverse. Recent studies in little- characterized marine environments point to extensive diversification of Malassezia-like organisms, providing exciting opportunities to explore the ecology, evolution and diversity of this enigmatic group.