This enzyme, which has been found mainly in plants, introduces a double bond at Delta8 of C18 and C20 fatty acids . The enzyme from the marine microalga Euglena gracilis requires a double bond to be present at Delta11 and is most active with 20:3 Delta11,14,17 and 20:2 Delta11,14 as substrates, although it can also desaturate 20:1 Delta11 . The Delta8-desaturation pathway represents an alternate pathway for the synthesis of the polyunsaturated fatty acids arachidonate (C20:4 Delta5,8,11,14) and eicosapentaenoate (C20:5 Delta5,8,11,14,17) in organisms lacking a Delta6-desaturase . The enzyme from the sunflower Helianthus annuus and from the herb Borago officinalis comprises a C-terminal desaturase domain and an N-terminal cytochrome-b5 domain .
exclusively produces (Z)-9-fluoro-8-phytosphingenine. This result is explained by an initial attack onto the C8-HR and syn-elimination of two vicinal hydrogen atoms via an anti-conformation of the substrate. An initial attack on the C9-F is excluded and generates no product
product predominantly transformed to (Z)-8-fluoro-8-phytosphingenine along with only trace amounts of the (E)-8-fluoro-8-phytosphingenine (ratio 95:5). This ratio indicates that the fluorinated substrate strongly favors the anti-configuration at the active center of the desaturase
DELTA8 sphingolipid desaturase creates double bonds in long-chain bases, i.e. sphingobases, such as sphinganine, phytosphinganine, or 4-sphingenine to produce E- and Z-isomers of 8-sphingenine, 8-phytosphingenine, or 4,8-sphingadienine, respectively
cloned into pBINI19-35S, transferred to Agrobacterium tumefaciens strain GV3101 and expressed in wild-type Arabidopsis Col 0 or in transgenic line CA1-9 expressing the Isochrysis galbana elongating activity IgASE1; cloned into the yeast expression vector pYES2 and expressed in Saccharomyces serevisiae strain W303-1A
functional expression in Saccharomyces cerevisiae, using the constitutive ADH1 promotor of the yeast expression vector pVT-U-102, results in synthesis of acylated (8E)- and (8Z)-4-hydroxy-8-sphingenine via N-acyl-4-hydroxysphinganine from fed deuterium-labeled palmitic acid, primary kinetic isotope effects, overview
gene S581, DNA and amino acid sequence determination and analysis, expression in Saccharomyces cerevisiae and constitutively in Arabidopsis thaliana, under control of the CaMV35S promoter, confers tolerance to aluminium and gadolinium, Gd3+, but not to lanthanum, La3+, or manganese, Mn2+, to cells and seedlings, respectively, the transgenic expression leads to the accumulation of 8(Z/E)-C18-phytosphingenine and 8(Z/E)-C20-phytopshingenine in yeast and to the accumulation of 8(Z/E)-C18-phytosphingenine in the leaves and roots of Arabidopsis plants, overview