English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

Palmitoleic acid (16:1Δ 9 ) possesses a double bond at the seventh carbon atom from methyl end of the acyl chain and belongs to unusual ω-7 monounsaturated fatty acids with broad applications in food, pharmaceuticals, cosmetics, biofuel, and other industries. This high-value fatty acid accumulates up to >40% of total lipid in the marine diatom  Phaeodactylum tricornutum.  The present study was conducted to determine the key gene responsible for 16:1Δ 9  biosynthesis in this unicellular alga. A new full-length cDNA and genomic DNA encoding acyl-ACP Δ 9  desaturase (PtAAD) were isolated from  P. tricornutum  cells. Expression levels of  PtAAD  gene under normal and stress culture conditions were both positively correlated with 16:1Δ 9  accumulation, implying its potential role for fatty acid determination. Functional complementation assay of a yeast mutant strain  BY4839  evidenced that  PtAAD  could restore the synthesis of unsaturated fatty acid, especially generating high levels of 16:1Δ 9 . Further transient expression of  PtAAD  gene in  Nicotiana benthamiana  leaves was accompanied by the accumulation of 16:1Δ 9 , which was absent from control groups. Three-dimensional structure modeling studies showed that functional domain of PtAAD contained three variant amino acids (F160, A223, and L156), which may narrow the space shape of substrate-binding cavity to ensure the entry of 16:0-ACP. Consistent with this prediction, the mutated version of  PtAAD  gene (F160L, A223T, and L156M) in  N. benthamiana  systems failed to accumulate 16:1Δ 9 , but increased levels of 18:1Δ 9 . Taken together, PtAAD exhibits a strong enzymatic activity and substrate preference for 16:0-ACP, acting as the key player for high biosynthesis and accumulation of 16:1Δ 9  in this alga. These findings provide new insights for better understanding the palmitoleic acid and oil biosynthetic mechanism in  P. tricornutum , indicating that  PtAAD  gene may have practical applications for enriching palmitoleic acid and oil yield in other commercial oleaginous algae and crops.

Characterization of a Novel Acyl-ACP Δ9 Desaturase Gene Responsible for Palmitoleic Acid Accumulation in a Diatom Phaeodactylum tricornutum