title: As(III) S-adenosylmethionine methyltransferases and other arsenic binding proteins.
abstract: Efflux is by far the most common means of arsenic detoxification is by methylation catalyzed by a family of As(III) S-adenosylmethionine (SAM) methyltransferases (MTs) enzymes designated ArsM in microbes or AS3MT in higher eukaryotes. The protein sequence of more than 5000 AS3MT/ArsM orthologues have been deposited in the NCBI database, mostly in prokaryotic and eukaryotic microbes. As(III) SAM MTs are members of a large superfamily of MTs involved in numerous physiological functions. ArsMs detoxify arsenic by conversion of inorganic trivalent arsenic (As(III)) into mono-, di- and trimethylated species that may be more toxic and carcinogenic than inorganic arsenic. The pathway of methylation remains controversial. Several hypotheses will be examined in this review.
authors.affiliation: Department of Atomic and Molecular Physics, LG-01, Academic Block -5, MIT Campus, Manipal University, Manipal - 576 104, Karnataka, India.
authors.forename: A Abdul
authors.initials: AA
authors.lastname: Ajees
authors.affiliation: Department of Cellular Biology and Pharmacology, Florida International University, Herbert Wertheim College of Medicine, Miami, Florida, USA 33199, 305-348-0657.
authors.forename: Barry P
authors.initials: BP
authors.lastname: Rosen