Selenium, accumulator plants

Selenocysteine HSeCH2CH(NH2)C00H Non-selenium accumulating plants Biologically active, protein type, selenium species... 

Selenocystathionine HOOC-CH(NH2)CH2-Se-CH2 Selenium accumulating plants Non-biologically active, non-protein, water-soluble... 

M. Montes Bayon, D. D. L. Due, N. Terry, J. A. Caruso, Selenium speciation in wild-type and genetically modiPed selenium accumulating plants with HPLC separation and ICP-MS/SE-MS detection, J. Anal. Atom. Spectrom., 17 (2002), 872D879. 

Selenium accumulator plants -Astragalus (Fabaceae), Oonopsis, Xybrrhiza (Asteraceae), Stanleya (Brassicaceae) spp. 

Selenium dioxide (= SeO. ) (Fabaceae) spp. Selenium accumulator plants — Reacts with thiols e.g. GSH — ... 

Oonopsis condensata (Asteraceae), Astragalus bisulcatus (Fabaceae) — selenium accumulating plants... 

I -Selenomethionine Selenium accumulating plants growing Yields Dimethyldiselenide,... 

Zhu, Y.Y., Liu, H.Q., Yin, X.B., and Zhou, S.B. In press. A preliminary investigation of selenium-accumulated plants in Enshi City, Hubei Province, China. Selenium Deficiency, Toxicity, and Biofortification for Human Health. USTC Press. 

The exclusion of selenium from the proteins of accumulator plants is thought to be the basis for their selenium tolerance. Their selenium metabolism is based mainly on water-soluble nonprotein forms such as selenium methylselenomethionine (Jacobs, 1989). The garlic odor characteristic of selenium-accumulator plants reflects the volatile organic compounds dimethylselenide and dime-thyldiselenide. Plants can suffer selenium toxicity as a result of selenium competition with essential metabolites for biochemical sites, replacement of essential ions by selenium, mainly major cations, selenate occupation of the sites of essential groups such as phosphate and nitrate, or selenium substimtion in essential sulfur compounds. 

Peterson, P.J. and Butler, G.W., 1967. Significance of selenocystathionine in an Australian selenium-accumulating plant, Neptunia amplexicaulis. Nature, 213 599—600. Porritt, R.E. and Swaine, D.J., 1976. Mercury and selenium in some Australian coals and fly-ash. Preprint, Institute of Fuel Conference Sydney, Paper 18, 9 pp. 

Se-enriched plants may be divided into two broad groups [199], i.e. selenium accumulators and/or selenium non-accumulators. Selenium-accumulating plants can be divided into three subgroups selenite-accumulators (broccoli and cucumber), selenomethionine accumulators (grains such as wheat, and mushrooms) and iS e-methyl selenomethionine accumulators (garlic and onion) [200]. 

Microbiol Mol Biol Rev 79 61-80. doi 10.1128/MMBR.00037-14 Neuhierl B, Bock A (1996) On the mechanism of selenium tolerance in selenium-accumulating plants purification and characterization of a specific selenocysteine methyltransferase from cultured cells of Astragalus bisulcatus. Eur 1 Biochem 239 235-238... 

Rosenfield and Beath (1964) classified plants into three groups based on their selenium uptake from seleniferous soils (i) selenium accumulator plants which can contain >1,000 mg kg selenium and grow well on high-selenium soils ... 

High selenium concentrations (7 12gkg dry mass) were found in the seeds of the selenium-accumulator plant coco de mono Lecythis ollaria). In order to obtain information on the protein-bound part of selenium in extracts of these seeds, Hammel et al used dialysis and SDS-PAGE combined with INAA. Extractions were carried out at pH 4.5 and 7.5. In both cases about 90% of the element was dissolved. By analyzing the protein fractions separated by SDS-PAGE the element was found to be present in extremely selenium-rich proteins with molecular masses below 20 kDa. 

V/A Low-approximately 80% of all forage and grain contain <0.05 ppm of selenium MA Variable-approximately 50% contains >0.1 ppm Adequate-80% of all forages and grain contain >0.1 ppm of selenium Local areas where selenium accumulator plant contain > 50 ppm X Selenium concentration in rainwater (pg/1) by sampling location... 

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