Yeast habitats: Different but global

Abstract

Yeasts, a taxonomically heterogenic group of unicellular fungi, populate many different habitats on our planet. They occur in aquatic and terrestrial environments and also in the atmosphere; however, they are not evenly distributed. While some species are ubiquitous generalists occurring in wide geographic range and dwelling in different habitats, others may have more restricted distribution either geographically or by habitats. Some are known from very few isolates, and about one third of the known yeast species are represented by only one strain. In these cases their ecology remains to be elucidated. As nonmotile organisms their dispersal depends on the vectors carrying them. Insects are of outstanding importance among yeast vectors. Several exciting questions can be raised about the habitat-yeasts-vector associations. For example, which yeasts are there? Why are they only there? How did they get there? What are they doing there? The last two decades witnessed the widespread application of DNA sequencing, providing quicker and more reliable yeast identification than earlier phenotypebased methods. Nowadays, the culture-independent methods are gaining ground in the study of biodiversity and ecology of yeasts. In this chapter some new achievements from the field of habitat-yeasts-vector system are introduced and are embedded in a broader context.