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, Volume 34, Issue 1–2, pp 103–105 | Cite as

CoA-independent transacylase has characteristics distinct from those of PLA2 enzymes

  • J. D. Winkler
  • C. -M. Sung
  • L. Huang
PLA2/5-Lipoxygenase

Abstract

CoA-independent transacylase (CoA-IT) catalyzes the transfer of arachidonic acid from acyl- to alkyl-linked phospholipids. The removal of arachidonic acid from the sn-2 position of the donor phospholipid is a PLA2-like reaction. However, examination of CoA-IT in U937 cells demonstrated that CoA-IT has many characteristics that are distinct from those of PLA2 enzymes, including activity in the absence of Ca2+, activity that was heat and acid unstable and stable in 10 mM 2-mercaptoethanol and that was inhibited by detergents. Compounds that inhibit PLA2 activity did not inhibit CoA-IT activity, including quinacrine, aristolochic acid and arachidonic acid. All of these characteristics of CoA-IT are in contrast to those of most PLA2 enzymes. These data suggest that CoA-IT is biochemically different from, and has a mechanism of action unique from, PLA2 enzymes.

Keywords

Arachidonic Acid U937 Cell Quinacrine Aristolochic Acid PLA2 Activity 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
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References

  1. [1]
    T. Sugiura, Y. Masuzawa, Y. Nakagawa and K. T. Waku,Transacylation of lyso-platelet-activating factor and other lysophospholipids by macrophage microsomes. Distinct donor and acceptor selectivities. J. Biol. Chem.262, 1199–1205 (1987).PubMedGoogle Scholar
  2. [2]
    J. D. Winkler, C.-M. Sung, C. F. Bennett and F. H. Chilton,Characterization of CoA-independent transacylase activity in U937 cells. Biochim. Biophys. Acta Lipids Lipid Metab.1081, 339–346 (1991).CrossRefGoogle Scholar
  3. [3]
    F. H. Chilton and T. R. Connell,1-Ether-linked phosphoglycerides. Major endogenous sources of arachidonate in the human neutrophil. J. Biol. Chem.263, 5260–5265 (1988).PubMedGoogle Scholar
  4. [4]
    C. C. Leslie, D. R. Voelker, J. Y. Channon, M. M. Wall and P. T. Zelarney,Properties and purification of an arachidonoyl-hydrolyzing phospholipase A 2 from a macrophage cell line, RAW 264.7. Biochim. Biophys. Acta963, 476–492 (1988).PubMedGoogle Scholar
  5. [5]
    E. Diez and S. Mong,Purification of a 56 kDa 1-O-hexadecyl-2-arachidonyl-sn glycero-3-phosphocholine hydrolytic phospholipase A 2 from human monocytic leukemic U937 cells. Calcium-dependent activation and membrane association. J. Biol. Chem.265, 14654–14661 (1990).PubMedGoogle Scholar
  6. [6]
    M. Waite,The Phospholipases. New York, Plenum Press, 1–332 (1987).Google Scholar
  7. [7]
    P. Vadas, E. Stefanski and W. Pruzanski,Characterization of extracellular phospholipase A 2 in rheumatoid synovial fluid. Life Sci.36, 579–587 (1985).CrossRefPubMedGoogle Scholar
  8. [8]
    S. Hara, I. Kudo, H. W. Chang, K. Matsuta, T. Miyamoto and K. Inoue,Purification and characterization of extracellular phospholipase A 2 from human synovial fluid in rheumatoid arthritis. J. Biochem. (Tokyo)105, 395–399 (1989).Google Scholar

Copyright information

© Birkhäuser Verlag 1991

Authors and Affiliations

  • J. D. Winkler
    • 1
  • C. -M. Sung
    • 1
  • L. Huang
    • 1
  1. 1.Department of PharmacologySmithKline Beecham PharmaceutialsKing of PrussiaUSA

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