Over-expression of LPAAT gene in Phaeodactylum tricornutum enhances fatty acid accumulation and increases fatty acid chain length

Abstract

Li: LPAAT gene in Phaeodactylum tricornutum enhances fatty acid accumulation To provide a potential method for improving microalgal lipid production, an over expression vector that expresses lysophosphatidic acid acyltransferase gene in Phaeodactylum tricornutum was constructed. Total fatty acid production incresed significantly in over-expression transformants and the length of fatty acids ranged from C14 to C22. The response to both lysophosphatidic acid acyltransferase over-and under-expression over the growth phase was also characterized. This study indicated a potential method to increase fatty acids accumulation in microalgae by employing a metabolic engineering approach.

A “CRISPY” tale on microalgal genome editing: featuring Nannochloropsis oceanica IMET1

“…On the other hand, the improved protein production under stress in the mutants could be hindering their growth properties. In line with the other studies, a 12.8 % increase in the lipid content of mutant B (13.02 g. gDW -1 ) under nitrogen starved condition compared to the WT (11.88 g. gDW -1 ) (Figure S1) [387,389,390]. However, the lipid contents in the mutant strains were lower compared to the WT under optimal conditions.…”

“…The C16:1 content in the TFA of mutant B was increased by 21% under nitrogen starved condition compared to the WT (Table S1). Similar variations in the fatty acid profiles were also reported in P. tricornutum where endogenous LPAAT overexpression improved the fatty acids with chain length C14 to C20 [389]. Under nitrogen starved conditions, mutant A depicted significantly slower growth rate, reduced lipid and EPA accumulation compared to mutant B and WT.…”

“…Codon harmonized BnLPAAT expression in N. oceanica Overexpression of LPAAT has been reported to enhance the lipid content in microalgae such as Chlamydomonas reinhardtii, Phaeodactylum tricornutum, Neochloris oleabundans and Chlorella sp. [387][388][389][390][391]. However, overexpression of LPAAT to tailor the accumulation of speci c fatty acids in TAGs was seldom reported in microalgae.…”

Microalgal-Based Bioenergy: Strategies, Prospects, and Sustainability

“…In general, there are three routes for biohydrogen production through microalgae. They comprise of (a) the photosystem II (PSII)-dependent hydrogen (H 2 ) production route, (b) the nutrient deprivation H 2 production pathway (i.e., absence of sulfur, nitrogen, phosphorus, and magnesium in the medium), and (c) the anaerobic biohydrogen generation pathway during dark fermentation. − In comparison to nitrogen, phosphorus, and magnesium deprivation, sulfur shortage was determined to be the most efficient method of biohydrogen synthesis. , The PSII activity and oxygen generation rate were both slowed by sulfur deficiency. Oxygen is used up during mitochondrial respiration, which triggers the biohydrogen evolution catalyzing enzyme hydrogenase under anaerobic conditions …”

“…Green algae, like Chlorella, Chlamydomonas, and S. obliquus, are the most common hosts for [FeFe]-hydrogenase. ,, Because of its one-of-a-kind H-cluster structure, hydrogenase of Chlorella is 10–100 times more catalytically active than other hydrogenases . The highly oxygen-sensitive nature of the hydrogenase enzyme also makes photolysis of algae quite challenging .…”