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

Search MEDLINE/PubMed


  • Title: Solubilization and characterization of the leukotriene C4 synthetase of rat basophil leukemia cells: a novel, particulate glutathione S-transferase.
    Author: Bach MK, Brashler JR, Morton DR.
    Journal: Arch Biochem Biophys; 1984 May 01; 230(2):455-65. PubMed ID: 6324687.
    Abstract:
    Rat basophil leukemia cell homogenates effectively catalyze the conversion of leukotriene A4 to a mixture of leukotrienes C4 and D4 in the presence of glutathione. These homogenates also catalyze the formation of adducts of halogenated nitrobenzene with glutathione, as determined spectrophotometrically. While all the classical glutathione S-transferase activity resides in the soluble fraction of the homogenates, the thiol ether leukotriene-generating activity is found in the particulate fraction. This "leukotriene C synthetase" activity has been solubilized from a crude high-speed particulate fraction by means of the nonionic detergent, Triton X-100. The solubilized enzyme is incapable of converting 2,4-dinitrochlorobenzene to a colored product in the presence of glutathione. Nor will it react with 3,4-dichloronitrobenzene. On the other hand, under optimal conditions, this enzyme preparation is capable of generating about 0.1 nmol leukotriene C mg protein-1 min-1 in a reaction which continues in linear fashion for at least 10 min. This dissociation in substrate specificity, as well as differences in the inhibition profile, distinguish the enzyme activity in the particulate fraction from rat basophil leukemia cell homogenates from the microsomal glutathione S-transferase which has been described in rat liver homogenates, suggesting that this "leukotriene C synthetase" is a new and unique enzyme.
    [Abstract] [Full Text] [Related] [New Search]