S. Mahadevan, P. Shukla, V. Kalyanaraman
Jan 1, 1969
Citations
0
Influential Citations
2
Citations
Journal
FEBS Letters
Abstract
Organic thiocyanates are known for their insecticidal, fungicidal and bactericidal properties [l-3] . In recent years, reports in the literature of their ability to act as anti-tumor and anti-hormonal agents [4,5 ] , have given impetus to the synthesis and pharmacological study of a variety of thiocyanic acid esters. However, the mode of action of these compounds at a molecular level is not well understood. Sexton [6] and Zsolnai [3] have indicated the possibility of the interaction of organic thiocyanates with thiol groups in the organism. During our studies on the substrate specificity of the enzyme nitrilase (3.5.5 . 1) from Aspergillus niger, we observed that phenylthiocyanate, which bears a structural resemblance to the substrate phenylacetonitrile, acted as a noncompetitive inhibitor. Similar inhibition was also observed with another C-N bond hydrolysing enzyme, riboflavin hydrolase (3.5.99.1) [7]. s ince both of these enzymes, nitrilase and riboflavin hydrolase, are “thiol” enzymes, sensitive to thiol reagents such as p-hydroxymercuribenzoate, N-ethylmaleimide etc., we examined the action of phenylthiocyanate on the activity of several enzymes with a view to determine the nature of its action. In this communication some preliminary observations on the interaction between thiol compounds and phenylthiocyanate as well as its action on some enzymes are reported.