Dataset Information

Caenorhabditis elegans Delta12-desaturase FAT-2 is a bifunctional desaturase able to desaturate a diverse range of fatty acid substrates at the Delta12 and Delta15 positions.

ABSTRACT: Caenorhabditis elegans FAT-2 has been characterized as fatty acid ?12-desaturase able to desaturate C16 and C18 fatty acids. However, in this report we show that when expressed in yeast cells this enzyme can also catalyze ?15 desaturation. This results in the production of both linoleic acid (?6 C18:2?9,12) and linolenic acid (?3 C18:3?9,12,15) from oleic acid (C18:1?9) substrate, and hexadecadienoic acid (?4 C16:2?9,12) and hexadecatrienoic acid (?1 C16:3?9,12,15) from palmitoleic acid (C16:1?9) substrate. In addition, this enzyme can also produce C14:2?9,12, C15:2?9,12, C17:2?9,12, and C18:4?6,9,12,15 when C14:1?9, C15:1?9, C17:1?9, and C18:3?6,9,12 substrates are available in yeast cells. Mass spectrometry analysis of 2,4-dimethyloxazoline modification of fatty acid methyl esters confirms the positions of all newly formed double bonds. These results indicate that when expressed in yeast the C. elegans ?12-desaturase CeFAT-2 shows a characteristic of a bifunctional ?12/?15-desaturase and has a great deal of elasticity with respect to fatty acid chain length in being able to accept fatty acids ranging from C14 to C18. Interestingly, despite possessing a bifunctional ?12/?15 desaturation activity, phylogenetic analysis suggests that C. elegans ?12-desaturase CeFAT-2 might have arisen independently from other reported dual ?12/?15-desaturases from fungi and protozoa.

SUBMITTER: Zhou XR

PROVIDER: S-EPMC3243535 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature

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Caenorhabditis elegans Delta12-desaturase FAT-2 is a bifunctional desaturase able to desaturate a diverse range of fatty acid substrates at the Delta12 and Delta15 positions.

Zhou Xue-Rong XR Green Allan G AG Singh Surinder P SP

The Journal of biological chemistry 20111031 51

Caenorhabditis elegans FAT-2 has been characterized as fatty acid Δ12-desaturase able to desaturate C16 and C18 fatty acids. However, in this report we show that when expressed in yeast cells this enzyme can also catalyze Δ15 desaturation. This results in the production of both linoleic acid (ω6 C18:2Δ9,12) and linolenic acid (ω3 C18:3Δ9,12,15) from oleic acid (C18:1Δ9) substrate, and hexadecadienoic acid (ω4 C16:2Δ9,12) and hexadecatrienoic acid (ω1 C16:3Δ9,12,15) from palmitoleic acid (C16:1Δ9 ...[more]

PMID: 22041902

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Dataset Information

Caenorhabditis elegans Delta12-desaturase FAT-2 is a bifunctional desaturase able to desaturate a diverse range of fatty acid substrates at the Delta12 and Delta15 positions.

Publications

Caenorhabditis elegans Delta12-desaturase FAT-2 is a bifunctional desaturase able to desaturate a diverse range of fatty acid substrates at the Delta12 and Delta15 positions.

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