Selenometabolomics Explored by Speciation

Abstract

Selenium (Se) belongs to the same group as sulfur in the periodic table but possesses certain chemical properties characteristic of a metal. It is an essential element in animals but becomes severely toxic when the amount ingested exceeds the required level. On the other hand, Se is not essential in plants although some plants are Se hyperaccumulators. Se changes into several chemical forms when metabolized. Thus, the identification of selenometabolites would enable us to formulate a metabolic chart of Se. Recently, speciation analysis by hyphenated techniques has contributed immensely to the study of selenometabolomes, i.e., the entirety of selenometabolites. Indeed, speciation has unveiled some unique selenometabolites in biological samples. The aim of this review is to present newly identified selenometabolites in animals and plants by speciation using hyphenated techniques and to delineate the perspectives of Se biology and toxicology from the viewpoint of speciation.

Protolytic Cleavage of Hg–C Bonds Induced by 1-Methyl-1,3-dihydro-2H-benzimidazole-2-selone: Synthesis and Structural Characterization of Mercury Complexes

“… 4 , 5 , 9 Furthermore, mercury may bind to the active sites of selenoenzymes and thereby inhibit their functions. 4 , 6 For example, selenium is a component of a variety of enzymes that incorporate the amino acids selenocysteine and selenomethionine (Figure 1 ), as illustrated by glutathione peroxidases, thioredoxin reductases, glycine reductases, formate dehydrogenases, and selenoprotein P. 4 , 5 , 7 , 10 Other examples of selenium-containing biomolecules include the amino acid derivatives selenoneine 11 , 12 and Se-methylselenoneine 12 , 13 (Figure 1 ), of which the latter was identified in human urine and blood.…”

Biological activity of selenorganic compounds at heavy metal salts intoxication

“…Уникальность этого процесса объясняется тем, что аминокислота селеноцистеин кодируется кодоном UGA, который обычно выступает в роли стоп-кодона [95,96]. Второй метаболический путь превращения селена связан с утилизацией избытка селена через реакции метилирования и образования селеносахаров, которые выводятся из организма с мочой [97].…”

Atomic spectrometry updates. Review of advances in elemental speciation

“…During the past year, two reviews have appeared. A comprehensive review of Se metabolism in cancer cells by Weekley et al 170 summarised recently published data on selenium speciation in cells and rat tissues with a range of techniques including X-ray absorption spectroscopy (XAS), X-ray uorescence microscopy (XFM), HPLC-ICP-MS and ESI-MS-MS. Ogra et al 171 focused on some selenometabolites recently identied in biological samples by speciation analysis. The paper is divided into two parts.…”