title: Crystallization and preliminary X-ray crystallographic analysis of the ArsM arsenic(III) S-adenosylmethionine methyltransferase.
abstract: Arsenic is the most ubiquitous environmental toxin and carcinogen and consequently ranks first on the Environmental Protection Agency's Superfund Priority List of Hazardous Substances. It is introduced primarily from geochemical sources and is acted on biologically, creating an arsenic biogeocycle. A common biotransformation is methylation to monomethylated, dimethylated and trimethylated species. Methylation is catalyzed by the ArsM (or AS3MT) arsenic(III) S-adenosylmethionine methyltransferase, an enzyme (EC 2.1.1.137) that is found in members of every kingdom from bacteria to humans. ArsM from the thermophilic alga Cyanidioschyzon sp. 5508 was expressed, purified and crystallized. Crystals were obtained by the hanging-drop vapor-diffusion method. The crystals belonged to the monoclinic space group C2, with unit-cell parameters a=84.85, b=46.89, c=100.35 A, beta=114.25 degrees and one molecule in the asymmetric unit. Diffraction data were collected at the Advanced Light Source and were processed to a resolution of 1.76 A.
authors.affiliation: Department of Cellular Biology and Pharmacology, Florida International University, Herbert Wertheim College of Medicine, Miami, Florida, USA.
authors.forename: Kavitha
authors.initials: K
authors.lastname: Marapakala
authors.forename: A Abdul
authors.initials: AA
authors.lastname: Ajees
authors.forename: Jie
authors.initials: J
authors.lastname: Qin
authors.forename: Banumathi
authors.initials: B
authors.lastname: Sankaran
authors.forename: Barry P
authors.initials: BP
authors.lastname: Rosen
mesh_terms: D003460:Crystallization; D018360:Crystallography, X-Ray; D008780:Methyltransferases / Q000737:chemistry*; D000461:Rhodophyta / Q000201:enzymology*
chemical_list: D008780:Methyltransferases
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