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Specific Occurence of Selenium in Certain Enzymes and Amino Acid Transfer Ribonucleic Acids |
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| Authors: | Thressa C Stadtman |
| Institution: | Laboratory of Biochemistry , National Heart, Lung and Blood Institute, National Institutes of Health , Bethesda, Maryland, 20205, USA |
| Abstract: | Abstract Some enzymes known to contain selenium are enumerated. In four of them which catalyze coupled oxidation-reduction reactions the selenium occurs exclusively in the form of selenocysteine residues. Their structure and function are described in detail. Two other bacterial enzymes which contain selenium in the form of a labile, readily dissociable component are also described. Results on the isolation, identification and structure determination of selenium-containing amino acid transfer ribonucleic acids are presented. These seleno-t RNA's are shown to contain either 5-methyl-aminomethyl-2-selenouridine or other 2-selenouridine derivatives. The role of selenium in a glutamate iso-accepter species is discussed. |
| Keywords: | Wittig reagents (1) N N′-2 5-cyclohexadiene-1 4-diylidene-bis(methanesulfonamide) (IIa) N N′-(2-chloro-2 5-cyclohexadiene-1 4-diylidene)bis(methanesulfonamide) (IIb) alkyl 1-[(methylsulfonyl)amino]-4-[(methylsulfonyl)imino]-α-(triphenylphosphoranylidene)-2 5-cyclohexadiene-1-acetate (IIIa b) N-[4-[(methylsulfonyl)amino]-4-[2-oxo-1- triphenvlphosphoranvlidene)-propyl]-2 5-cyclohexadien-1-ylidene] methanesulfonamide (IIIc) N-[4-[(meihylsulfonyl)amino]-4-[2-oxo-2-phenyl-1-(triphenylphosphoranylidene)ethyl]-2 5-cyclohexadien-1-ylidene] methanesulfonamide (IIId) |