@article {647,
	title = {Interaction of trivalent axsenicals with metallothionein},
	journal = {Chemical Research in Toxicology},
	volume = {16},
	number = {7},
	year = {2003},
	note = {ISI Document Delivery No.: 702UQTimes Cited: 53Cited Reference Count: 625th International Conference on Arsenic Exposure and Health EffectsJUL 14-18, 2002SAN DIEGO, CALIFORNIA},
	month = {Jul},
	pages = {873-880},
	type = {Proceedings Paper},
	abstract = {Arsenic is a human carcinogen, causing skin, bladder, and lung cancers. Although arsenic in drinking water affects millions of people worldwide, the mechanism(s) of action by which arsenic causes cancers is not known. Arsenic probably exerts some toxic effects by binding with proteins. However, few experimental data are available on arsenic-containing proteins in biological systems. This study reports on arsenic interaction with metallothionein and established binding stoichiometries between metallothionein and the recently discovered trivalent metabolites of arsenic metabolism. Size exclusion chromatography with inductively coupled plasma mass spectrometry analysis of reaction mixtures between trivalent arsenicals and metallothionein clearly demonstrated the formation of complexes of arsenic with metallothionein. Analysis of the complexes using electrospray quadrupole time-of-flight tandem mass spectrometry revealed the detailed binding stoichiometry between arsenic and the 20 Cys residues in the metallothionein molecule. Inorganic arsenite (As-III) and its two trivalent methylation metabolites, monomethylarsonous acid (MMA(III)) and dimethylarsinous acid (DMA(III)), readily bind with metallothionein. Each metallothionein molecule could bind with up to six As-III, 10 MMA(III), and 20 DMA(III) molecules, consistent with the coordination chemistry of these arsenicals. The findings on arsenic interaction with proteins are useful for a better understanding of arsenic health effects.},
	keywords = {ARSENIC METABOLITES, ENZYMATIC METHYLATION, GLUTATHIONE-REDUCTASE, HUMAN URINE, INORGANIC ARSENICALS, MONOMETHYLARSONOUS ACID MMA(III), PYRUVATE-DEHYDROGENASE, RABBIT LIVER, THIOREDOXIN REDUCTASE, TOXICITY},
	isbn = {0893-228X},
	url = {<Go to ISI>://000184243200009},
	author = {Jiang, G. F. and Gong, Z. L. and Li, X. F. and Cullen, W. R. and Le, X. C.}
}
@article {386,
	title = {Determination of arsenic metabolic complex excreted in human urine after administration of sodium 2,3-dimercapto-1-propane sulfonate},
	journal = {Chemical Research in Toxicology},
	volume = {15},
	number = {10},
	year = {2002},
	note = {ISI Document Delivery No.: 607TXTimes Cited: 15Cited Reference Count: 42},
	month = {Oct},
	pages = {1318-1323},
	type = {Article},
	abstract = {Sodium 2,3-dimercapto-1-propane sulfonate (DMPS) has been used to treat acute arsenic poisoning. Presumably DMPS functions by chelating some arsenic species to increase the excretion of arsenic from the body. However, the excreted complex of DMPS with arsenic has not been detected. Here we describe a DMPS complex with monomethylarsonous acid (MMA(III)), a key trivalent arsenic in the arsenic methylation process, and show the presence of the DMPS-MMA(III) complex in human urine after the administration of DMPS. The DMPS-MMA(III) complex was characterized using electrospray tandem mass spectrometry and determined by using HPLC separation with hydride generation atomic fluorescence detection (HGAFD). The DMPS-MMAIII complex did not form a volatile hydride with borohydride treatment. On-line digestion with 0.1 M sodium hydroxide following HPLC separation decomposed the DMPS-MMA(III) complex and allowed for the subsequent quantification by hydride generation atomic fluorescence. Arsenite (As-III), arsenate (As-V), monomethylarsonic, acid (MMA(V)), dimethylarsinic acid (DMA(V)), MMA(III), and DMPS-MMA(III) complex were analyzed in urine samples from human subjects collected after the ingestion of 300 mg of DMPS. The administration of DMPS resulted in a decrease of the DMA(V) concentration and an increase of the MMA(V) concentration excreted in the urine, confirming the previous results. The finding of the DMPS-MMA(III) complex in human urine after DMPS treatment provides an explanation for the inhibition of arsenic methylation by DMPS. Because MMA(III) is the substrate for the biomethylation of arsenic from MMA(V) to DMA(V), the formation of DMPS-MMA(III) complex would reduce the availability of MMA(III) for the subsequent biomethylation.},
	keywords = {ARSENICALS, CHALLENGE TEST, DRINKING-WATER, ENZYMATIC, GLUTATHIONE-REDUCTASE, HUMAN HEPATOCYTES, IN-VITRO INHIBITION, LIVER, METHYLATED, METHYLATION, MONOMETHYLARSONOUS ACID MMA(III), RABBIT, THIOREDOXIN REDUCTASE},
	isbn = {0893-228X},
	url = {<Go to ISI>://000178807800016},
	author = {Gong, Z. and Jiang, G. F. and Cullen, W. R. and Aposhian, H. V. and Le, X. C.}
}
