Publication Cover
Xenobiotica
the fate of foreign compounds in biological systems
Volume 9, 1979 - Issue 11
5
Views
27
CrossRef citations to date
0
Altmetric
Research Article

Some Properties of the Sulphoxidases and Sulphoxide Reductases of the CestodeMoniezia Expansa, the Nematode Ascaris Suum and Mouse Liver

&
Pages 675-679 | Received 22 Mar 1979, Published online: 22 Sep 2008
 

Abstract

1. The anthelmintics bithionol, phenothiazine, albendazole and fenbendazole were oxidized to sulphoxides by enzymes in the cytosol of the proglottids of the cestode Moniezia expansa and the cytosol of the intestinal epithelial cells of the nematode Ascaris suum. Enzymes in these tissues were also able to reduce these sulphoxides to the thioethers in the absence of oxygen.

2. Sulphoxidation and sulphoxide reduction also occurred in mouse liver enzyme preparations. About 20% of the sulphoxidation activity was not associated with microsomes and was not inhibited by CO; about 50% of the reductase activity was found in the microsomes.

3. The pH optima for sulphoxidases from both helminths were in the range 7.0-7.2, and both required NADH or NADPH for activity. Low molecular weight thiols and flavins did not affect sulphoxidation. Enzyme activity was inhibited by 0.1 mM Cu2+, Hg2+, Cd2+ or Zn2+ and by p-chloromercuribenzoate or N-ethylmaleimide.

4. Both helminth sulphoxide reductases displayed pH optima in the range 7.2-7.4, and required NADH or NADPH for activity. Oxygen inhibited the reductases.

Reprints and Corporate Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

To request a reprint or corporate permissions for this article, please click on the relevant link below:

Academic Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

Obtain permissions instantly via Rightslink by clicking on the button below:

If you are unable to obtain permissions via Rightslink, please complete and submit this Permissions form. For more information, please visit our Permissions help page.