Lu, Y and Zhou, W and Wei, L and Li, J and Jia, J and Li, F and Smith, SM and Xu, J, Regulation of the cholesterol biosynthetic pathway and its integration with fatty acid biosynthesis in the oleaginous microalga Nannochloropsis oceanica, Biotechnology for Biofuels, 7, (81) pp. 1-15. ISSN 1754-6834 (2014) [Refereed Article]
Licensed under Creative Commons Attribution 4.0 International (CC BY 4.0) http://creativecommons.org/licenses/by/4.0/
Sterols are vital structural and regulatory components in eukaryotic cells; however, their biosynthetic pathways and functional roles in microalgae remain poorly understood.
In the oleaginous microalga Nannochloropsis oceanica, the sterol biosynthetic pathway produces phytosterols as minor products and cholesterol as the major product. The evidence together with their deduced biosynthetic pathways suggests that N. oceanica exhibits features of both higher plants and mammals. Temporal tracking of sterol profiles and sterol-biosynthetic transcripts in response to changes in light intensity and nitrogen supply reveal that sterols play roles in cell proliferation, chloroplast differentiation, and photosynthesis. Furthermore, the dynamics of fatty acid (FA) and FA-biosynthetic transcripts upon chemical inhibitor-induced sterol depletion reveal possible co-regulation of sterol production and FA synthesis, in that the squalene epoxidase inhibitor terbinafine reduces sterol content yet significantly elevates free FA production. Thus, a feedback regulation of sterol and FA homeostasis is proposed, with the 1-deoxy-D-xylulose 5-phosphate synthase (DXS, the committed enzyme in isoprenoid and sterol biosynthesis) gene potentially subject to feedback regulation by sterols.
These findings reveal features of sterol function and biosynthesis in microalgae and suggest new genetic engineering or chemical biology approaches for enhanced oil production in microalgae.
|Item Type:||Refereed Article|
|Keywords:||microalgae, biosynthesis, cholesterol, fatty acid, Nannochloropsis oceanica|
|Research Division:||Biological Sciences|
|Research Group:||Plant Biology|
|Research Field:||Plant Physiology|
|Objective Division:||Expanding Knowledge|
|Objective Group:||Expanding Knowledge|
|Objective Field:||Expanding Knowledge in the Biological Sciences|
|UTAS Author:||Smith, SM (Professor Steven Smith)|
|Web of Science® Times Cited:||18|
|Deposited By:||Plant Science|
|Downloads:||326 View Download Statistics|
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