The Desulfuration of Thiourea by Thyroid Cytoplasmic Particulate Fractions
Year: 1959
Type: article
Abstract: Thiourta, a goitrogen (1, 2) and an inhibitor of the iodination of tyrosyl groups in the thyroid (3), is itself metabolized by this organ.The sulfur of thiourea is converted largely to inorganic sulfate (4, 5) and partially to protein-bound sulfur and two unidentified sulfur compounds (5).Recently thiosulfatel has also been found among the products of the metabolism in viva of thiourea by the rat thyroid.This report will describe a cytoplasmic particulate system in vitro from mammalian thyroid which desulfurates thiourea to sulfur-containing products similar to those observed in vivo.EXPERIMENTAL 1Materials-S35-thiourea C?4-thiourea were obtained from the iew and SVhiocyanate England Nuclear Corporation; the specific activities ranged from 15.0 to 40.0 mc. per mmole.The chromatographically pure compounds were dissolved in tripledistilled water, and the solutions were stored at -20".S%ulfide in 0.02 N NaOH, with a specific activity of 4.2 mcuries per mmole, was obtained from the same source.Dehydroascorbic acid, potassium selenocyanate, and 3,4-dichlorophcnylserine were kindly furnished by Drs.I'.L. Munson, J. Wolff, and D. Gilbert, respectively.Thyroglobulin (Preparation CH-%9,91921 A) was supplied by Dr. R. L. Kroc of the Warner-Chilcott Laboratories.DPNH and TPNH were obtained from the Sigma Chemical Company.Wherever necessary, rompounds were neutralized with potassium hydroxide before use.Preparation of Thyroid Cytoplasmic Particulate Fractions-Thyroids from freshly killed sheep were obtained at local abattoirs, chilled on ice, and cleaned of extraneous matter.The tissue was minced with a razor blade and disintegrated with 9 volumes of 0.25 M sucrose-O.027M KHC08 in a chilled Servall Omni-Mixer run at half speed for 15 seconds.The mixture was ground gently in a chilled homogenizer of the Potter-Elvehjem type until a homogeneous suspension resulted.Unbroken cells, nuclei, and tissue debris
Source: Journal of Biological Chemistry
Authors: F. Maloof, L. Spector
Institutions: Harvard University, Massachusetts General Hospital
Language: English
Subfield: Endocrinology, Diabetes and Metabolism
Field: Medicine
Domain: Health Sciences
Open Access status: hybrid
Estimated APC paid: $3,430
OpenAlex ID: W1859374232