Lipids

, Volume 44, Issue 7, pp 621–630

Characterization of Both Polyunsaturated Fatty Acid Biosynthetic Pathways in Schizochytrium sp.

  • J. Casey  Lippmeier
  • Kristine S. Crawford
  • Carole B. Owen
  • Angie A. Rivas
  • James G. Metz
  • Kirk E. Apt
Original Article

DOI: 10.1007/s11745-009-3311-9

Cite this article as:
Lippmeier, J.C., Crawford, K.S., Owen, C.B. et al. Lipids (2009) 44: 621. doi:10.1007/s11745-009-3311-9

Abstract

Schizochytrium produces long chain polyunsaturated fatty acids (PUFAs) via a PUFA synthase. Targeted mutagenesis of one gene of this synthase was conducted to confirm PUFA synthase function and determine its metabolic necessity. The resulting mutants were auxotrophic and required supplementation with PUFAs. In vivo labeling experiments with radioactive fatty acids demonstrated the presence of several elongase and desaturase activities associated with the standard pathway of PUFA synthesis. However, this system was missing a critical Δ12 desaturase activity and was therefore not capable of synthesizing PUFAs from the 16- or 18-carbon saturated fatty acid products of the fatty acid synthase. Because Schizochytrium uses a PUFA synthase system for the production of PUFAs, the existence of a partial desaturase-elongase system (if not a simple vestige) is suggested to be either a scavenging mechanism for intermediate fatty acids prematurely released by the PUFA synthase or for PUFAs found in the organism’s native environment.

Keywords

Fatty acid metabolismMetabolismPolyunsaturated fatty acids (PUFA)Specific lipidsRadiotracerAnalytical techniquesMarine lipid biochemistryGeneral areaMolecular biologyMiscellaneous

Abbreviations

DHA

Docosahexaenoic acid

DPA

Docosapentaenoic acid

Copyright information

© AOCS 2009

Authors and Affiliations

  • J. Casey  Lippmeier
    • 1
  • Kristine S. Crawford
    • 1
  • Carole B. Owen
    • 1
  • Angie A. Rivas
    • 1
  • James G. Metz
    • 2
  • Kirk E. Apt
    • 1
  1. 1.Martek Biosciences CorporationColumbiaUSA
  2. 2.Martek Biosciences CorporationBoulderUSA