title: Microbial production of dihomo-γ-linolenic acid by Δ5-desaturase gene-disruptants of Mortierella alpina 1S-4.
abstract: We constructed dihomo-γ-linolenic acid (DGLA)-producing strains with disruption of the Δ5-desaturase (Δ5ds) gene, which encodes a key enzyme catalyzing the bioconversion of DGLA to arachidonic acid (ARA), by efficient gene-targeting, using Δlig4 strain of Mortierella alpina 1S-4 as the host. In previous study, we had already identified and disrupted the lig4 gene encoding DNA ligase 4, which involves in non-homologous end joining, in M. alpina 1S-4, and the Δlig4 strain had showed efficient gene-targeting. In this study, the uracil auxotroph of Δlig4 strain was constructed, and then transformed for disruption of Δ5ds. The isolation of nine Δ5ds-disruptants out of 18 isolates indicated that the disruption efficiency was 50%. The ratio of DGLA among the total fatty acids of the Δ5ds-disruptants reached 40.1%; however, no ARA was detected. To our knowledge, this is the first study to report the construction of DGLA-producing transformants by using the efficient gene-targeting system in M. alpina 1S-4.
authors.affiliation: Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa-oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kikukawa
authors.affiliation: Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa-oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan; Institute of Technology and Science, Tokushima University, 2-1 Minami-Josanjima, Tokushima 770-8506, Japan.
authors.forename: Eiji
authors.initials: E
authors.lastname: Sakuradani
authors.affiliation: Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa-oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan; Research Unit for Physiological Chemistry, Kyoto University, Kitashirakawa-oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan.
authors.forename: Akinori
authors.initials: A
authors.lastname: Ando
authors.affiliation: Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa-oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan.
authors.forename: Tomoyo
authors.initials: T
authors.lastname: Okuda
authors.affiliation: Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa-oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan; Department of Bioscience and Biotechnology, Faculty of Bioenvironmental Science, Kyoto Gakuen University, 1-1 Nanjo, Sogabe, Kameoka 621-8555, Japan.
authors.forename: Sakayu
authors.initials: S
authors.lastname: Shimizu
authors.affiliation: Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa-oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan; Research Unit for Physiological Chemistry, Kyoto University, Kitashirakawa-oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan. Electronic address: ogawa@kais.kyoto-u.ac.jp.
authors.forename: Jun
authors.initials: J
authors.lastname: Ogawa
mesh_terms: D015126:8,11,14-Eicosatrienoic Acid / Q000378:metabolism*; D016718:Arachidonic Acid / Q000032:analysis / Q000096:biosynthesis; D019149:Bioreactors; D059766:DNA End-Joining Repair; D011088:DNA Ligases / Q000172:deficiency / Q000235:genetics; D000090943:Delta-5 Fatty Acid Desaturase; D044943:Fatty Acid Desaturases / Q000172:deficiency* / Q000235:genetics* / Q000378:metabolism; D018390:Gene Targeting; D060847:Metabolic Engineering; D020094:Mortierella / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism*
chemical_list: D000090943:Delta-5 Fatty Acid Desaturase; D016718:Arachidonic Acid; D044943:Fatty Acid Desaturases; D011088:DNA Ligases; D015126:8,11,14-Eicosatrienoic Acid
keywords: Dihomo-γ-linolenic acid; Gene-targeting; Mortierella alpina; Polyunsaturated fatty acid; Δ5-desaturase