3- Mercaptopyruvate sulfurtransferase

Duo S, Lea TC, Stipanuk MH. 1983. Developmental pattern, tissue distribution, and subcellular distribution of cysteine -ketoglutarate aminotransferase and 3-mercaptopyruvate sulfurtransferase activities in the rat. Biol Neonat 43 23-32. 

An important property of 3-mercaptopyruvate arises from electron withdrawal by the carbonyl group. This makes the SH group electrophilic and able to be transferred as SH+, S°, to a variety of nucleophiles (Eq. 24-44). Thus sulfite yields thiosulfate (S2032 + H+, Eq. 24-45, step a), cyanide yields thiocyanate (Eq. 24-45, step b), and cysteine sulfinate yields alanine thiosulfonate.448 461 The reactions are catalyzed by mercaptopyruvate sulfurtransferase, an enzyme very similar to thiosulfate sulfurtransferase. The latter is a liver enzyme often called by the traditional... 

The first hint of an essential role of molybdenum in metabolism came from the discovery that animals raised on a diet deficient in molybdenum had decreased liver xanthine oxidase activity. There is no evidence that xanthine oxidase is essential for all life, but a human genetic deficiency of sulfite oxidase or of its molybdopterin coenzyme can be lethal. The conversion of molybdate into the molybdopterin cofactor in E. coli depends upon at least five genes. In Drosophila the addition of the cyanolyzable sulfur (Eq. 16-64) is the final step in formation of xanthine dehydrogenase. It is of interest that sulfur (S°) can be transferred from rhodanese (see Eq. 24-45), or from a related mercaptopyruvate sulfurtransferase into the desulfo form of xanthine oxidase to generate an active enzyme. ... 

Sorbo B (1975). Thiosulphate sulfurtransferase and mercaptopyruvate sulfurtransferase. In Metabolic Pathways, Volume 7, Metabolism of Sulfur Compounds (DM Greenberg, ed.), pp. 433-456. New York, NY, USA Academic Press. 

At lease four intracellular enzymes may be involved for cyanide detoxification. The generalized reactions of rhodanese, mercaptopyruvate sulfurtransferase, thiosulfate reductase, and cystathionase are shown within the cell. 

Jarabak R, Westley J. Steady-state kinetics of 3-mercaptopyruvate sulfurtransferase from bovine kidney. Arch Biochem Biophys. 1978 185 458-465. 

Porter DW, Baskin SI. The effect of three a-keto acids on 3-mercaptopyruvate sulfurtransferase activity. J Biochem Toxicol. 1996 11 45-50. 

B. Sorho, Thiosulfate sulfurtransferase and mercaptopyruvate sulfurtransferase, jji "Metaholism of Sulfur Compounds, Vol. 

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