Mechanism of enzymatic and non-enzymatic tyrosine iodination Inhibition by excess hydrogen peroxide and/or iodide

Enzymatic iodination of tyrosine and thyroglobulin with chloroperoxidase.

1. Crystalline chloroperoxidase is effective in catalyzing the iodination of tyrosine or thyroglobulin when supplemented with HzOz, or with the H20z-generating system, glucoseglucose oxidase. The iodination reaction is very rapid at low concentrations of iodide (5 X 10-5 M), and at low concentrations of tyrosine (1 X 10V4 M) or thyroglobulin (0.33 mg per ml). 2. Iodide is rapidly bound as 3-iod...

Non-enzymatic oxidation of tyrosine and dopa.

4Winge, 0., and Roberts, C., Comp. Rend. Trav. Lab., Carlsb., Ser. Physiol., 24, 263-315 (1948). 5 Ryan, F. J., and Schneider, L. K., Genetics, 34, 72-91 (1949). 6 Luria, S. E., and Delbruck, M., Ibid., 28, 491-511 (1943). 7Mundkur, B., and Lindegren, C. C., Am. J. Botany, 36, 722-727 (1949). 8 Lea, D. E., and Coulson, C. A., J. Genetics, 49, 264-285 (1949). 9Spiegelman, S., Cold Spring Harbor ...

Enzymatic iodination of Sindbis virus proteins.

Sindbis virus was iodinated by using the enzyme lactoperoxidase, an iodination technique which labels only surface proteins. By this technique, the two viral glycoproteins are labeled, and the internal viral protein is not. The two glycoproteins are iodinated to strikingly different extents. This difference in susceptibility to iodination apparently is due to the position or conformation of the...

In-situ Enzymatic Generation of Hydrogen Peroxide for Bleaching Purposes

Bleaching detergent formulations contain environmentally unfriendly bleaching agents (perborates and percarbonates), which cause aquatic eutrophication, although without these compounds detergents are much less efficient for the washing processes. In an effort to replace these compounds, in this study, hydrogen peroxide was generated as a bleaching compound by means of enzymatic reactions. Thre...

Mechanism of the inhibition of enzymatic halogenation by antithyroid agents.