Purification, Crystallization, and Preliminary Crystallographic Studies of Human As(III) S-Adenosylmethionine Methyltransferase (hAS3MT)

• Published in: Crystallography reports Vol. 66; no. 7; pp. 1311 - 1315
• Main Authors: Radhakrishnan, M., Packianathan, C., Sankaran, B., Kandavelu, P., Rosen, B. P.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01.12.2021; Springer Nature B.V
• Subjects: Arsenic; BASIC BIOLOGICAL SCIENCES; Carcinogens; Crystallization; Crystallography; Crystallography and Scattering Methods; Physics; Physics and Astronomy; Structure of Macromolecular Compounds; Unit cell
• ISSN: 1063-7745; 1562-689X; 1562-689X
• DOI: 10.1134/S1063774521070129

Exposure to environmental arsenic is associated with serious of health issues such as cancer, diabetes and developmental delays in infants and children. In human liver, As(III) S-adenosylmethionine methyl transferase (hAS3MT) (EC 2.1.1.137) was proposed to be an detoxification process by methylation of inorganic arsenite into pentavalent methyl MAs(V) and dimethyl arsenite DMAs(V). More recently the first product was shown to be highly toxic and potentially carcinogenic trivalent methylarsenite (MAs(III)). Our studies are designed to elucidate the mechanism of AS3MT and its contribution to arsenic-related diseases. Here, we report the first crystallization and preliminary X-ray diffraction analysis of the human AS3MT enzyme. The crystals belong to the monoclinic P 12 1 1 space group with unit cell parameters of a = 135.03 Å, b = 260.44 Å, c = 279.03 Å, α = 90.00°, β = 93.36°, γ = 90.00°.