@article {ISI:000264792600048,
	title = {Redox photochemistry of methionine by sulfur K-edge X-ray absorption spectroscopy: potential implications for cataract formation.},
	journal = {J. Am. Chem. Soc.},
	volume = {131},
	number = {10},
	year = {2009},
	month = {mar},
	pages = {3577{\textendash}82},
	abstract = {The photochemistry of methionine, methionine sulfoxide, and methionine sulfone have been investigated by using sulfur K-edge X-ray absorption spectroscopy to explore the redox photochemical processes under different conditions. Methionine is easily photooxidized to the sulfoxide and the sulfone in the presence of dioxygen. In the absence of oxidant, photoirradiation leads to the one-electron-oxidized cation radical with no further reaction, suggesting that an alternative mechanism for photooxidation of thioethers through direct oxidation is feasible. The photochemistry of methionine sulfoxide allows for independent oxidative and reductive processes. Photoreduction of the sulfoxide leads back to the parent thioether under both aerobic and anaerobic conditions. Photooxidation occurs only under aerobic conditions. In contrast, methionine sulfone is photochemically inert. These results provide new insights into potential photochemical processes that may lead to cataract formation.},
	keywords = {Cataract, Cataract: etiology, METHIONINE, Methionine: chemistry, Oxidation-Reduction, PHOTOCHEMISTRY, Spectrum Analysis, Spectrum Analysis: methods, sulfur redox, XAS},
	issn = {1520-5126},
	doi = {10.1021/ja806946r},
	url = {http://www.ncbi.nlm.nih.gov/pubmed/19226173},
	author = {Karunakaran-Datt, Anusha and Kennepohl, Pierre}
}
@article {Kennepohl2009,
	title = {X-ray spectroscopic approaches to the investigation and characterization of photochemical processes.},
	journal = {J. Syncr. Rad.},
	volume = {16},
	number = {Pt 4},
	year = {2009},
	pages = {484{\textendash}8},
	publisher = {International Union of Crystallography},
	abstract = {Despite a wealth of studies exemplifying the utility of the 2-5 keV X-ray range in speciation and electronic structure elucidation, the exploitation of this energy regime for the study of photochemical processes has not been forthcoming. Herein, a new endstation set-up for in situ photochemical soft X-ray spectroscopy in the 2-5 keV energy region at the Stanford Synchrotron Radiation Lightsource is described for continuous photolysis under anaerobic conditions at both cryogenic and ambient temperatures. Representative examples of this approach are used to demonstrate the potential information content in several fields of study, including organometallic chemistry, biochemistry and materials chemistry.},
	keywords = {Absorptiometry, METHIONINE, Methionine: analogs \& derivatives, Methionine: radiation effects, ORGANOMETALLIC COMPOUNDS, Organometallic Compounds: chemistry, Organometallic Compounds: radiation effects, Photochemical Processes, Photon, Photon: methods, Synchrotrons},
	issn = {1600-5775},
	doi = {10.1107/S0909049509021384},
	url = {http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=2698811\&tool=pmcentrez\&rendertype=abstract},
	author = {Kennepohl, Pierre and Wasinger, Erik C and DeBeer George, Serena}
}
@article {4718,
	title = {Antimony biomethylation by Scopulariopsis brevicaulis: characterization of intermediates and the methyl donor},
	journal = {Chemosphere},
	volume = {41},
	number = {11},
	year = {2000},
	note = {ISI Document Delivery No.: 345WVTimes Cited: 15Cited Reference Count: 23},
	month = {Dec},
	pages = {1717-1725},
	type = {Article},
	abstract = {The filamentous fungus Scopulauiopsis brevicaulis biomethylates inorganic antimony(III) compounds to trimethylstibine, that can be detected in culture headspace gases. Dimethylantimony and trimethylantimony species have been detected in the medium of these cultures, but the origin of these species was controversial. We now show that the dimethylantimony species is a true intermediate on the pathway to trimethylstibine (rather than arising from trimethylstibine oxidation or as an analytical artifact) because no dimethylantimony species are formed on trimethylstibine oxidation, as determined by using HG-GC-AAS. Furthermore, the dimethylantimony and trimethylantimony species can be separated, by using anion exchange chromatography, and so the dimethylantimony species is not an analytical artifact, formed during the hydride generation process. The antimony biomethylation mechanism was further probed by measuring incorporation of the methyl group, from (CD3)-C-13-L-methionine and CD3-D-methionine, into methylantimony species and, for comparison, into methylarsenic species. The percentage incorporation of the labeled methyl group into methylarsenic and methylantimony species was not significantly different. The incorporation from (CD3)-C-13-L-methionine was 54\% and 47\% for antimony and arsenic, respectively. The incorporation from CD3-D-methionine was 20\% and 16\% for antimony and arsenic, respectively. It appears that the biomethylation of arsenic and antimony occur by very similar, perhaps identical, mechanisms. (C) 2000 Elsevier Science Ltd. All rights reserved.},
	keywords = {APIOTRICHUM-HUMICOLA, arsenic, dimethylantimony, GENERATION, GROWTH, INFANT-DEATH-SYNDROME, INORGANIC ANTIMONY, METHIONINE, RELEVANCE, Scopulariopsis brevicaulis, SPECIATION, trimethylantimony, TRIMETHYLARSINE, trimethylstibine, trimethylstibine oxidation},
	isbn = {0045-6535},
	url = {<Go to ISI>://000088838900002},
	author = {Andrewes, P. and Cullen, W. R. and Polishchuk, E.}
}
