Anaerobic biosynthesis of unsaturated fatty acids in the cyanobacterium,Oscillatoria limnetica

✍ Scribed by L. L. Jahnke; B. Lee; M. J. Sweeney; H. P. Klein

• Book ID: 104762264
• Publisher: Springer
• Year: 1989
• Tongue: English
• Weight: 302 KB
• Volume: 152
• Category: Article
• ISSN: 0302-8933
• DOI: 10.1007/bf00409653

✦ Synopsis

The mechanism for synthesis of monounsaturated fatty acids under aerobic and anaerobic conditions was studied in the facultative anaerobic cyanobacterium, Oscillatoria limnetica. The hexadecenoic acid (C16:1) of aerobically grown O. limnetica was shown to contain both the A7 (79%) and A 9 (21%) isomers, while the octadecenoic (C18:1) acid was entirely the A9 acid. Incorporation of [2-14C] acetate into the fatty acids under aerobic conditions resulted in synthesis of the A7 and A9 C16:1 and the A9 C18:1. Synthesis of unsaturated fatty acids in the presence of DCMU required sulfide. Anaerobic incubations in the presence of DCMU and sulfide (less than 0.003% atmospheric oxygen) resulted in a two-fold increase in monounsaturated fatty acids of both A 7 and A 9 C16:1 and A 9 and A 11 C18:1. The synthesis of these isomers is characteristic of a bacterialtype, anaerobic pathway.