Molecular characterization of Yarrowia lipolytica strains isolated from different environments and lipase profiling

Abstract

In order to analyze yeasts that produce industrial compounds, it is essential to identify them accurately. Yarrowia lipolytica is one of the most extensively studied 'nonconventional' yeasts, being a strictly aerobic microorganism capable of producing important metabolites and having an intense secretory activity, which justifies efforts to use it in industry (as a biocatalyst), in molecular biology, and in studies of genetics. Therefore, in this study, an accurate identification of Y. lipolytica strains was performed using 3 different molecular biological methods (RFLP analysis of ITS1-5.8S rDNA-ITS2 and 18S rDNA regions and sequencing of the D1/D2 domain of the 26S rDNA region). The 26S rRNA gene sequence of the strains showed sequence homology with various Y. lipolytica strains from the National Center for Biotechnology Information. A number of different lipids (tributyrin, olive oil, and fish oil) were screened in terms of the growth of Y. lipolytica strains and lipase production. It was determined that all lipid-related substrates supported lipase production levels ranging from 4.27 U/mL (tributyrin) to 37.08 U/mL (fish oil). Fish oil (1%) showed maximum specific activity in the supernatant (264.85 U/mg of protein) and TEM TAN 46. The Y. lipolytica strain that was produced in the media containing fish oil was found to be the best lipase producer.