Manipulation of carbon flux into fatty acid biosynthesis pathway in Dunaliella salina using AccD and ME genes to enhance lipid content and to improve produced biodiesel quality

Talebi, Ahmad Farhad; Tohidfar, Masoud; Bagheri, Abdolreza; Lyon, Stephen R.; Salehi-Ashtiani, Kourosh; Tabatabaei, Meisam

doi:10.18331/BRJ2015.1.3.6

Manipulation of carbon flux into fatty acid biosynthesis pathway in Dunaliella salina using AccD and ME genes to enhance lipid content and to improve produced biodiesel quality

Document Type : Research Paper

Authors

Ahmad Farhad Talebi ¹^{, 2}

Masoud Tohidfar ²^{, 3}

Abdolreza Bagheri ⁴

Stephen R. Lyon ⁵

Kourosh Salehi-Ashtiani ⁶

Meisam Tabatabaei ²^{, 3}

¹ Semnan university, Semnan, Iran.

² Energy Crops Genetic Engineering Group, Biofuel Research Team (BRTeam), Karaj, Iran.

³ Microbial Biotechnology and Biosafety Dept, Agricultural Biotechnology Research Institute of Iran (ABRII), Karaj, Iran.

⁴ Biotechnology and Plant Breeding Dept., College of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran.

⁵ AlgaXperts, LLC, Milwaukee, Wisconsin, USA.

⁶ Division of Science and Math, and Center for Genomics and Systems Biology (CGSB), New York University Abu Dhabi, P.O. Box 129188, Abu Dhabi, UAE.

10.18331/BRJ2015.1.3.6

Abstract

Advanced generations of biofuels basically revolve around non-agricultural energy crops. Among those, microalgae owing to its unique characteristics i.e. natural tolerance to waste and saline water, sustainable biomass production and high lipid content (LC), is regarded by many as the ultimate choice for the production of various biofuels such as biodiesel. In the present study, manipulation of carbon flux into fatty acid biosynthesis pathway in Dunaliella salina was achieved using pGH plasmid harboring AccD and ME genes to enhance lipid content and to improve produced biodiesel quality. The stability of transformation was confirmed by PCR after several passages. Southern hybridization of AccD probe with genomic DNA revealed stable integration of the cassette in the specific positions in the chloroplast genome with no read through transcription by indigenous promoters. Comparison of the LC and fatty acid profile of the transformed algal cell line and the control revealed the over-expression of the ME/AccD genes in the transformants leading to 12% increase in total LC and significant improvements in biodiesel properties especially by increasing algal oil oxidation stability. The whole process successfully implemented herein for transforming algal cells by genes involved in lipid production pathway could be helpful for large scale biodiesel production from microalgae.

Graphical Abstract