|
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 |
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