Ecology and biodiversity of yeasts with potential value in biotechnology

Abstract

In the latest edition of the standard treatise of yeasts, in 1998, 700 species were described. Since then, the number of recognized yeast species has doubled, with a steep increase particularly in the number of the basidiomycetous yeasts. Of all these yeast species, only about a dozen is used at industrial scale, and some 70-80 species have been shown at laboratory scale to possess potential value in biotechnology; their ratio is, in the best case, 5-10%. If it is accepted, that according to a modest estimate, the known yeast species represent only 5 % of the total number which may inhabit the Earth, then there is ample room to search for new species with novel potential to exploit. Where could these yeasts be discovered? In recent years we are witnessing great progress in exploring the diverse ecological niches of yeasts, and revealing the great diversity of species living in the various habitats. Still, compared to the profusing metabolic capability of bacteria living in the soil, surprisingly less is known about the soil yeasts. Much remains to be learned on yeasts associated with insects, invertebrates and fishes in the deep ocean, inhabiting tropical forests, or striving in extreme environments. It could reasonably be expected, that among the numerous species to be discovered in specific and unusual habitats, many will be found to possess enzymes, carry out metabolic routes and show physiological properties which hold out promises to be valuable for biotechnological applications. This chapter will examine these potential values from the point of view of ecology and biodiversity of yeasts © 2009 Springer Netherlands.