title: Yeast peroxisomes: structure, functions and biotechnological opportunities.
abstract: Peroxisomes are ubiquitous organelles found in most eukaryotic cells. In yeasts, peroxisomes play important roles in cell metabolism, especially in different catabolic processes including fatty acid β-oxidation, the glyoxylic shunt and methanol metabolism, as well as some biosynthetic processes. In addition, peroxisomes are the compartment in which oxidases and catalase are localized. New peroxisomes mainly arise by fission of pre-existing ones, although they can also be formed from the endoplasmic reticulum (ER). Peroxisomes consist of matrix-soluble proteins and membrane proteins known as peroxins. A total of 34 PEX peroxin genes and proteins have been identified to date. and their functions have been elucidated. Protein import into peroxisomes depends on peroxins and requires specific signals in the structure of transported proteins: PTS1, PTS2 and mPTS. The mechanisms of metabolite penetration into peroxisomes are still poorly understood. Peroxisome number and the volume occupied by these organelles are tightly regulated. Methanol, fatty acids and methylamine act as efficient peroxisome proliferators, whereas glucose and ethanol induce peroxisome autophagic degradation (pexophagy). To date, 42 Atg proteins involved in pexophagy are known. Catabolism and alcoholic fermentation of the major pentose sugar, xylose, depend on peroxisomal enzymes. Overexpression of peroxisomal transketolase and transaldolase activates xylose fermentation. Peroxisomes could be useful as target organelles for overexpression of foreign toxic proteins.
authors.affiliation: Department of Molecular Genetics and Biotechnology, Institute of Cell Biology, NAS of Ukraine, Drahomanov Street, 14/16, Lviv 79005, Ukraine Department of Biotechnology and Microbiology, University of Rzeszow, Zelwerowicza 4, Rzeszow 35-601, Poland sibirny@yahoo.com.
authors.forename: Andriy A
authors.initials: AA
authors.lastname: Sibirny
mesh_terms: D001709:Biotechnology / Q000379:methods*; D007218:Industrial Microbiology / Q000379:methods*; D020675:Peroxisomes / Q000378:metabolism* / Q000648:ultrastructure*; D012441:Saccharomyces cerevisiae / Q000378:metabolism*
keywords: peroxins; peroxisomal enzymes; peroxisome propagation; peroxisome targeting; pexopahgy; xylose alcoholic fermentation