Identification of Δ9-elongation activity from Thraustochytrium aureum by heterologous expression in Pichia pastoris

Abstract

The Δ9-elongase isolated from qÜê~ìëíçÅÜóíêáìã=~ìêÉìã, which contains a high level of polyunsaturated fatty acids (PUFAs), was demonstrated to be associated with the synthesis of C20 PUFAs. The q~bil gene contains a 825 bp ORF that encodes a protein of 274 amino acids that shares a high similarity with other PUFA elongases.

Isolation of a novel C18-Δ9 polyunsaturated fatty acid specific elongase gene from DHA-producing Isochrysis galbana H29 and its use for the reconstitution of the alternative Δ8 pathway in Saccharomyces cerevisiae

“…These results showed that the amino acid sequences of C18-D9-PUFA-specific elongases from different origins shared high identity whether they originated from the same species or not. In spite of having D9 PUFA elongation activity, BAI40363 with wide substrate specificity from M. alpine (Sakuradani et al 2009), CAM55867 with D9, D6 and D5 elongation activities from T. aureum (Lee et al 2008), and TaNE with D9, D6 and D5 elongation activities and D5 desaturation activity from T. aureum ATCC34304 (Kang et al 2010) were only 24, 20 and 6% identical with IgASE2. Moreover, IgASE2 displayed a low identity with D6 elongases and D5 elongases, e.g., 20, 18 and 20, 22% identity with the D6 and D5 PUFA elongases of Pyramimonas cordata (Petrie et al 2010a) and Thraustochytrium sp.…”

“…To date, only four C18-D9-PUFAs-specific elongases have been identified: IgASE1 from the microalga Isochrysis galbana (Qi et al 2002), Emihu-d9E from Emiliania huxleyi, Pavpi-d9E from Pavlova pinguis and Pavsa-d9E from Pavlova salina (Petrie et al 2010a, b). Recently, three multifunctional enzymes with D9 elongase activities, TaELO (Lee et al 2008), TaNE (Kang et al 2010) and MALCE1 (Sakuradani et al 2009), were reported. There is, thus, a great interest in identifying highly efficient genes that can increase the flux of fatty acids from LA and ALA to DHA.…”

Transgenic Biosynthesis of Polyunsaturated Fatty Acids: A Sustainable Biochemical Engineering Approach for Making Essential Fatty Acids in Plants and Animals

“…Des: Ac, Acanthamoeba castellanii ; , At, Arabidopsis thaliana ; Cb, Caenorhabditis briggsae ; Cc, Coprinus cinereus ; Ce, Caenorhabditis elegans ; Ci, Ctenopharyngodon idella ; Cr, Chlamydomonas reinhardtii ; Dl, Dicentrarchus labrax L.; Eg, Euglena gracilis ; Gm, Gadus morhua L.; Lc, Lates calcarifer ; Ma, Mortierella alpina ; Pl, Pavlova lutheri ; Po, Portulaca oleracea L.; Pt, Phaeodactylum tricornutum ; Ss, Salmo salar . Elo: Ig, Isochrysis galbana ; Mp, Marchantia polymorpha L.; Pi, Parietochloris incise ; Pp, Physcomitrella patens ; Ps, Pavlova salina ; Ta, Thraustochytrium aureum . PKS: S, Schizochytrium sp.…”

Production of cis -11-eicosenoic acid by Mortierella fungi

“…In the previous study, it was revealed that Δ9EL derived from Thraustochytrium aureum converts fatty acid substrates with the first double bond at the nine carbon atom position away from the carboxyl end (Δ9‐position) such as OA, linoleic acid (18:2 ω 6, LA) and α ‐linolenic acid (18:3 ω 3, ALA) through the sequential addition of C 2 units from malonyl‐CoA (Lee et al . ). As for higher plants, a fatty acid elongase 1 ( FAE1 ) showing Δ9EL‐like activity catalyses the condensation of malonyl‐CoA with a long‐chain acyl‐CoA to give a 3‐ketoacyl‐CoA, which is reduced to 3‐hydroxyacyl‐CoA, dehydrated to enoyl‐CoA and finally reduced to an elongated acyl‐CoA (Somerville et al .…”