These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Photolysis of "purple" lipoxygenase: implications for the structure of the chromophore.
    Author: Nelson MJ, Chase DB, Seitz SP.
    Journal: Biochemistry; 1995 May 09; 34(18):6159-63. PubMed ID: 7742320.
    Abstract:
    Treatment of soybean lipoxygenase isozyme 1 with its substrates, linoleic acid and oxygen, or product, 13(S)-hydroperoxy-9,11(Z,E)-octadecadienoic acid (13-HPOD), leads to the appearance of a purple color. Although the structure of the chromophore has not been determined, we present strong evidence that it is an Fe(3+)-OOR complex between the enzyme and 13-HPOD. Irradiation of frozen purple solutions of lipoxygenase causes the reversible production of a radical, shown by the effects of 2H and 17O enrichment on its EPR spectrum to be derived from 13-HPOD. The action spectrum of the photolysis reaction corresponds to the visible spectrum of the purple species, strongly implying that the purple chromophore contains 13-HPOD (or a product thereof) as part of its structure. Concomitant with the production of this radical there is a decrease in the intensity of an EPR signal corresponding to enzyme-bound Fe3+ and characteristic of the purple species. Taken together, these observations support the suggestion that the purple species is a complex between ferric lipoxygenase and 13-HPOD, likely the ferric peroxide.
    [Abstract] [Full Text] [Related] [New Search]