type	Journal Article
authors	Mizutani, T.
title	Some evidence of the enzymatic conversion of bovine suppressor phosphoseryl-tRNA to selenocysteyl-tRNA
journal	FEBS Lett
Activity	2.9.1.2
Family	2.9.1.2
ui	89325556
year	(1989)
volume	250
number	2
pages	142-6.
keywords	Amino Acids/analysis
abstract	In order to clarify the mechanisms of selenocysteine incorporation into glutathione peroxidase, some evidence to show the in vitro conversion of phosphoseryl-tRNA to selenocysteyl-tRNA is reported. [3H]Phosphoseryl-tRNA was incubated in a reaction mixture composed of SeO2, glutathione and NADPH in the presence of selenium-transferase partially purified. Analyses of amino acids on the product tRNA showed that a part (4%) of [3H]phosphoseryl-tRNA was changed to [3H]selenocysteyl-tRNA. The conversion from seryl-tRNAsu or major seryl- tRNAIGA was not found. Selenium-transferase was essential for the conversion. [3H]Selenocysteine, liberated from the tRNA, was modified with iodoacetic acid. The product was confirmed to be carboxymethyl- selenocysteine by two-dimensional TLC. Selenocysteyl-tRNAsu should be used to synthesize glutathione peroxidase by co-translational mechanisms.
last changed	2010/01/12 13:20