Selenomethionine is a naturally occurring selenium-containing amino acid . The L- enantiomer of selenomethionine, known as Se-Met (SEM), is an important dietary source of selenium. It is found in the fruits of Brazil nuts , grains , soybeans and other legumes . Se- methyl selenocysteine or its γ-glutamyl derivative is the most significant source of selenium; it is found in asparagus , onions and cabbage [1] .
| Selenomethionine | |
|---|---|
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| General | |
| Chem. formula | C 5 H 11 NO 2 Se |
| Physical properties | |
| Molar mass | 196.106 g / mol |
| Classification | |
| Reg. CAS number | |
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| Reg. EINECS number | |
| Smiles | |
| Inchi | |
| RTECS | |
| Chebi | |
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In vivo, selenomethionine is sometimes randomly incorporated into the peptide chain instead of methionine . Selenomethionine is rapidly oxidized [2] . Its antioxidant activity is due to its ability to neutralize reactive oxygen species . Selenium and sulfur are chalcogenes , and their chemical properties are largely similar, so the replacement of methionine with selenomethionine has only a limited effect on the structure and function of the protein . However, the penetration of selenomethionine into tissue proteins and keratin in horses causes alkaline disease ( alkalosis ). Alkalosis is characterized by exhaustion, hair loss, deformation and shedding of hooves, loss of vitality, and destruction of joints of long bones.
The insertion of selenomethionine into proteins instead of methionine facilitates the determination of the protein structure by X-ray diffraction analysis using or [3] . The inclusion of a heavy atom in a protein, such as, for example, a selenium atom, allows one to solve the X-ray diffraction analysis [4] .
It has been suggested that selenomethionine, which is an organic form of selenium, is more easily absorbed by the human body than selenite (inorganic form) [5] . During clinical trials, it was found that selenomethionine is absorbed 19% better than selenite [5] . The anticancer effect of selenomethionine is presumably due to its ability to enzymatically (using the methioninase enzyme) cleavage to methaneslenol (CH 3 SeH), which is supposed to play an extremely important role in the fight against cancer [6] [7] .
See also
- Selenocysteine , another selenium-containing amino acid.
- Selenoproteins
Notes
- ↑ PD Whanger, Selenocompounds in plants and animals and their biological significance, Journal of the American College of Nutrition , 21 (3), 223–232 (2002).
- ↑ E. Block, M. Birringer, W. Jiang, T. Nakahodo, HJ Thompson, PJ Toscano, H. Uzar, X. Zhang, and Z. Zhu, Allium chemistry: synthesis, natural occurrence, biological activity, and chemistry of Se -alk (en) ylselenocysteines and their γ-glutamyl derivatives and oxidation products, J. Agric. Food Chem. , 49 , 458-470 (2001).
- ↑ WA Hendrickson, Maturation of MAD phasing for the determination of macromolecular structures, Journal of Synchrotron Radiation , 6 (4), 845-851 (1999).
- ↑ AM Larsson, Preparation and crystallization of selenomethionine protein, IUL Biotechnology Series, 8 (Protein Crystallization) , 135-154 (2009).
- ↑ 1 2 Product Review: Supplements for Cancer Prevention (Green Tea, Lycopene, and Selenium) . ConsumerLab.com . Date of treatment April 20, 2008.
- ↑ H. Zeng; M. Wu; JH Botnen, Methylselenol, a selenium metabolite, induces cell cycle arrest in G1 phase and apoptosis via the extracellular-regulated kinase 1/2 pathway and other cancer signaling genes F, Journal of Nutrition , 139 (9), 1613-1618 (2009) .
- ↑ H. Zeng; M. Briske-Anderson; M. Wu; MP Moyer, Methylselenol, a selenium metabolite, plays common and different roles in cancerous colon HCT116 cell and noncancerous NCM460 colon cell proliferation, Nutrition and Cancer , 64 , 128-135 (2012).