Abstract
Mucor circinelloides, an oleaginous filamentous fungus, is gaining popularity due to its ability to synthesize significant amounts of lipids containing γ-linolenic acid (GLA) that have important health benefits. Malic enzyme (ME), which serves as the main source of NADPH in some fungi, has been found to regulate lipid accumulation in oleaginous fungi. In the present study, the role of two cytosolic ME genes, cmalA and cmalB, in the lipid accumulation of the M. circinelloides high-lipid-producing strain WJ11, was evaluated. Strains overexpressing cmalA and cmalB showed a 9.8- and 6.4-fold rise in specific ME activity, respectively, and an elevation of the lipid content by 23.2% and 5.8%, respectively, suggesting that these genes are involved in lipid biosynthesis. Due to increased lipid accumulation, overall GLA content in biomass was observed to be elevated by 11.42% and 16.85% in cmalA and cmalB overexpressing strains, respectively. Our study gives an important insight into different studies exploring the role of the cmalA gene, while we have for the first time investigated the role of the cmalB gene in the M. circinelloides WJ11 strain.
Highlights
For decades microbial oil has been regarded as an important substitute for oils derived from plants
Though the cmalA gene has been studied in other strains of M. circinelloides, we investigated it for the first time in the WJ11 strain
A study on the development of embryos in rapeseed has shown that Malic enzyme (ME) may have a role in the synthesis of fatty acids [65]. This is the first study to investigate the role played in the accumulation of lipids by cytosolic ME genes cmalA and cmalB in the M. circinelloides WJ11 strain, though previously the cmalA gene has been evaluated for its role in the accumulation of lipids in the CBS 277.49 strain
Summary
For decades microbial oil has been regarded as an important substitute for oils derived from plants. Microbial oil was generated commercially for the first time in 1985 but was found to be too expensive compared to the plant source [1]. Microbial oil was regarded as an important generator for the production of novel fatty acids that were difficult to be generated via agricultural means [1]. The medicinal significance of PUFAs has been investigated intensively in the past decades [7]. Together, these factors have contributed to the emergence of microbial oil being valuable in terms of industry and economics. Microbial lipid production is becoming attractive because of its extensive utilization as a biofuel and nutraceutical source [8–11]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
