Oleic acid induces expression in of oleate utilizing genes saccharomyces cerevisiae

Abstract

The yeast Saccharomyces cerevisiae preferentially use glucose as a carbon source. Glycolysis pathway plays a pivotal role in utilizing glucose to yield ATP for the cell. In the presence of glucose, genes required for the alternative carbon utilization pathways (i.e. gluconeogenesis, bata-oxidation) are inactivated. However, when glucose is absent, other carbon sources such as fatty acids can be alternatively used for growth. S. cerevisiae are able to use fatty acids such as oleic acid to generate cellular biomass and metabolic energy. Oleic acid utilization depends on enzyme in b-oxidation pathway which occured in peroxisomes, leading to the breakdown of oleic acid to acetyl-CoA which is then utilized via the glyoxylate cycle. A wide range of peroxisomal proteins and the enzymes necessary for breakdown of oleic acid are induced by oleate. In this study, some selected genes which encode for the key enzymes of pathway required for oleic acid utilization were selected to test for the expression levels during growth on oleic acid as a sole carbon source. Quantitative real time polymerase reaction (qRT-PCR) analysis showed increase in the mRNA levels of the b-oxidation, glyoxylate and gluconeogenesis genes (relative expression levels).