Selenium containing amino acids and proteins in marine algae

The assimilation ofelements ingested by marine planktonic bivalve larvae

“…High levels of Se have also been observed in the soluble fractions of the chlorophytes Dunaliella tertiolecta (7 3% soluble) and ChZorella sp. (98% soluble) (Bottino et al 1984).…”

Analytical selenoamino acid studies by chromatography with interfaced atomic mass spectrometry and atomic emission spectral detection

“…Wrench has reported the presence of selenomethionine selenoxide in marine phytoplankton, determined by elution similarity to the methionine sulfoxide analog [21]. Bottino et al suggested the presence of Se-methyl-DL-selenocysteine selenoxide and selenone in marine algae, determined by similar retention (ion exchange) and similar mobility (thin layer chromatography) to the sulfur analogs [22]. The only report of the presence of selenoxides in plants was made by Spare et al, tentatively identifying the presence of Se-methyl-DL-selenocysteine-selenoxide, Se-[β-carboxypropyl]-selenocysteine selenoxide, and γ-glutamyl-Se-DL-propenyl-selenocysteine [12].…”

“…The inductively coupled plasma mass spectrometer (ICP-MS ) is an effective element specific HPLC detector which has been applied to a number of selenium speciation studies [22,[33][34][35][36][37][38][39]. In this paper, as part of an ongoing study of the cancer chemopreventive activity of selenium, extracts of selenium containing samples are analyzed by HPLC-ICP-MS and by chloroformate derivatization GC-AED.…”

Selenium fractionation and cycling in the intertidal zone of the Carquinez Strait. Annual report, October 1, 1995--December 31,1996

“…In biota, all of the above mentioned organo-Se forms have been reported to occur as the structural components of amino acids and proteins (Ganther, 1974;Bottino et al, 1984;Stadtman, 1990). Other organo-Se compounds such as seleno-urea, -inosine, -guanosine in which Se forms double bonds with C, which in turn is linked to amine or amide groups have been synthesized, but their occurrences in the biological systems have not been reported so far.…”

“…While the main Se contributors to the San Francisco Bay are from both natural sources (primarily as Se0:-through rivers receiving drainage from agricultural lands of the San Joaquin Valley, California (Presser and Ohlendorf, 1988)), and anthropogenic sources (as SeO: -from local oil refinery discharges (Cutter, 1989)), Se in the surface water occurs in a number of forms, including dissolved species, species adsorbed onto suspended particulate matter, and phytoplankton-Se. Particle-adsorbed Se(vI) and Se(IV) may undergo modifications by reacting with the unsaturated C-0 bonds and by displacing S from -SH groups of the dissolved and particle bound humic substances, and also by reacting with similar functional groups within the algal cells (Bottino et al, 1984;Luoma et al, 1992;Besser et al, 1993;Amarathunga and Milne, 1994). Such reactions can transform inorganic Se into organo-Se forms mentioned above, and although direct speciation is not possible, the presence of organo-Se compounds has been suggested in Bay waters, based on indirect methods (Cutter, 1989).…”