Production of 5,8,11-eicosatrienoic acid by a delta5 and delta6 desaturation activity-enhanced mutant derived from a delta12 desaturation activity-defective mutant of Mortierella alpina 1S-4.
Enhanced production of 5,8,11-eicosatrienoic acid (Mead acid, 20:3omega9) was attained with a mutant fungus, Mortierella alpina JT-180, derived from delta12 desaturation activity-defective and delta6 desaturation activity-enhanced M. alpina M209-7. Production of 20:3omega9 by JT-180 was 1.4 times greater than that of the parent strain M209-7. This is thought to be due to its enhanced Delta5 desaturation activity, which was 3.3 times higher than that of M209-7. In both strains, 78.5-80.4% of the total lipids comprised triacylglycerol (TG), and 76.6-79.0% of 20:3omega9 was present in TG. Comparing the fatty acid compositions among various lipid species, the highest percentages (24.1-37.6%) of 20:3omega9 in total lipids were found in phosphatidylcholine. For optimization of 20:3omega9 production by JT-180, a glucose concentration of 4% in the culture medium and shifting of the growth temperature from 28 degrees C to 20 degrees C on the 2nd day were shown to be effective. Under optimal conditions, 20:3omega9 production by JT-180 reached 1.92 g/l culture medium in a 10-l jar fermentor (corresponding to 81.5 mg/g dry mycelia and 18.3% of total fatty acids), which is greater than that reported previously from M209-7 (1.65 g/l).
Sakuradani
E
E
Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa-oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan.
Kamada
N
N
Hirano
Y
Y
Nishihara
M
M
Kawashima
H
H
Akimoto
K
K
Higashiyama
K
K
Ogawa
J
J
Shimizu
S
S
D015126:8,11,14-Eicosatrienoic Acid / Q000031:analogs & derivatives* / Q000378:metabolism*; D003470:Culture Media; D044943:Fatty Acid Desaturases / Q000502:physiology*; D005227:Fatty Acids / Q000032:analysis; D005947:Glucose / Q000494:pharmacology; D020094:Mortierella / Q000254:growth & development / Q000378:metabolism*; D009154:Mutation; D013696:Temperature
D003470:Culture Media; D005227:Fatty Acids; D044943:Fatty Acid Desaturases; D015126:8,11,14-Eicosatrienoic Acid; D005947:Glucose; C010944:mead acid