%0 Journal Article
%T Yeast Methylotrophy: Metabolism, Gene Regulation and Peroxisome Homeostasis
%A Hiroya Yurimoto
%A Masahide Oku
%A Yasuyoshi Sakai
%J International Journal of Microbiology
%D 2011
%I Hindawi Publishing Corporation
%R 10.1155/2011/101298
%X Eukaryotic methylotrophs, which are able to obtain all the carbon and energy needed for growth from methanol, are restricted to a limited number of yeast species. When these yeasts are grown on methanol as the sole carbon and energy source, the enzymes involved in methanol metabolism are strongly induced, and the membrane-bound organelles, peroxisomes, which contain key enzymes of methanol metabolism, proliferate massively. These features have made methylotrophic yeasts attractive hosts for the production of heterologous proteins and useful model organisms for the study of peroxisome biogenesis and degradation. In this paper, we describe recent insights into the molecular basis of yeast methylotrophy. 1. Introduction Reduced C1-compounds, such as methane and methanol, are relatively abundant in nature. Methylotrophs, that have the ability to utilize C1-compounds as the sole source of carbon and energy, also appear to be ubiquitous in nature. A diverse range of prokaryotes and eukaryotes can utilize C1-compounds for growth, and methylotrophs have a diverse range of metabolic pathways for assimilating and dissimilating C1-compounds [1¨C4]. Prokaryotic methylotrophs can utilize a variety of C1-compounds (e.g., methane, methanol, methylamine), while eukaryotic methylotrophs can only use methanol as a carbon source, and methylamine not as a carbon source but as a nitrogen source. The latter group of organisms is limited to a number of yeast genera including Candida, Pichia, and some genera that were recently separated from Pichia, that is, Ogataea, Kuraishia, and Komagataella [5]. Since the first isolation in 1969 [6], methylotrophic yeasts have been studied intensively in terms of both physiological activities and potential applications. In the early 1970s, production of single cell protein (SCP) using methanol as a carbon source was studied intensively [7, 8]. These studies established a high-cell-density cultivation method although large-scale production of SCP from methanol was eventually found not to be economically feasible. The metabolic pathways involved in methanol assimilation and dissimilation and characterization of the enzymes have been described in Hansenula polymorpha (Pichia angusta) and Candida boidinii [9¨C12]. One major finding was the strong inducibility of these enzymes by methanol. A variety of genes encoding enzymes and proteins involved in methanol metabolism have since been cloned, and the regulation of methanol-inducible gene expression has been studied [13, 14]. Methylotrophic yeasts also have been used as model organisms for
%U http://www.hindawi.com/journals/ijmicro/2011/101298/