Nice new paper that may be of interest: PLOS Pathogens: From Dandruff to Deep-Sea Vents: Malassezia-like Fungi Are Ecologically Hyper-diverse by Anthony Amend.
Malassezia are commonly found in many studies of human skin and when they have been found in other places sometimes it is thought that they are vagrants having come from the skin of humans or other animals. And they are certainly found relatively commonly in buildings and other human occupied locales. For example see:
- The Impact of Sampler Selection on Characterizing the Indoor Microbiome
- Recent Advances in the Microbiology of the Built Environment
- The Diversity and Distribution of Fungi on Residential Surfaces
- Microbial Communities Associated with House Dust
and more. Given the widespread “natural” distribution of this group of organisms it seems reasonable that one should no longer assume that the Malassezia one finds in a building has to be coming from skin.
7 thoughts on “Nice paper on Malassezia-like Fungi – commonly found in human skin – but also found in many other places”
It makes sense that Malassezia would be under-represented in past culture-based surveys because it doesn’t grow on standard fungal media. It requires special media containing lipids. I have a bottle of Cremora on my chemical shelf just for cultivating the Malassezia strains in the Phaff Yeast Culture Collection at UC Davis. The Cremora agar is a much cleaner emulsion than the old messy olive oil/surfactant recipe.
Do you know if anyone uses Cremora or things like it for general culturing do try and make sure they capture Malassezias that are out there?
As for me, I use olive oil in culturing only when I’m specifically trying to get Malassezia.
We are continuously mixing-up the Human microbiome with the building microbiome. Malassezia does not grow in buildings, but it is usually detected in buildings because humans and animals occupy buildings. The problem is that DNA methods cannot distinguish between growing organisms and settled, and even dead fragments of “Malassezia-like” fungi. What is that? Amanita phalloides is deadly, while A. caesarea is gourmet food. Who would eat an Amanita-like fungus. The building microbiome has to be characterized better, anything else is speculation. PLEASE use direct observation methods in combination with sequencing when you characterize the source of microorganisms. In many cases like Malassezia you are simply detecting a sink.
The paper here discusses the issue of DNA vs. living and I am (relatively) convinced that they are detecting living species in these diverse environments. See the section “How Do We Know that Malassezia Detected in Marine Environmental DNA Aren’t Contaminants?”
I have read the article. Marine organisms also have Malassezia on their skin/scales
excellent point …