Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04040 (Catalase)
 3,577 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Initiation with methionine of the synthesis of rat liver catalase [EC 1.11.1.6] has been investigated. Analysis of the N-terminal residue of nascent catalase peptides labeled in vivo with injected radioactive amino acids, including [3H]methionine, indicated a remarkably high content of methionine. By fractionating [3H]methionine-labeled nascent catalase according to chain length, it was found that peptides of shorter chain length contained more N-terminal methionine relative to total methionine incorporated. In addition, only a small amount of [3H]methionine was detected as the N-terminal amino acid when newly completed catalase was examined by Edman degradation. These results indicate that the synthesis of liver catalase is initiated with methionine, and suggest the presence of a mechanism for its subsequent removal from the N-terminal position. Catalase was also synthesized in a cell-free system directed by the catalase mRNA, using [3H]Met-tRNAf or [3H]Met-tRNAm. The results obtained in such in vitro experiments were in good agreement with those from in vivo studies, and further showed that the N-terminal methionine was provided by a specific initiator tRNA, i.e. tRNA Met f.
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PMID:Studies on rat liver catalase. IX. Role of methionine in polypeptide chain inhibition. 89 58

The synthesis of glutathione peroxidase from [75Se]selenite was studied in slices and cell-free extracts from rat liver. The incorporation of [75Se]selenocysteine at the active site was detected by carboxymethylation and hydrolysis of partially purified glutathione peroxidase (glutathione:hydrogen peroxide oxidoreductase, EC 1.11.1.9) in the presence of [3H]selenocysteine and subsequent amino acid analysis. The synthesis of glutathione peroxidase in slices was inhibited by cycloheximide or puromycin and 75Se was incorporated from [75Se]selenite into free selenocysteine and selenocysteyl tRNA. Increasing concentrations of selenocystine caused a progressive dilution of the 75Se and a corresponding decrease in glutathione peroxidase labeling. In cell-free systems, [75Se]selenocysteyl tRNA was the best substrate for glutathione peroxidase synthesis. These results indicate the existence in rat liver of the de novo synthesis of free selenocysteine and a translational pathway of selenocysteine incorporation into glutathione peroxidase.
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PMID:In vitro synthesis of glutathione peroxidase from selenite. Translational incorporation of selenocysteine. 621 28

The Halobacterium salinarum catalase-peroxidase gene was subcloned into shuttle vectors pWL102 and pWL202 and expressed under the control of different archaeal promoters. When Hbt. salinarum was transformed with the catalase-peroxidase gene under the control of its own promoter, catalase-peroxidase activity increased twofold. Catalase-peroxidase activity increased threefold when Hbt. salinarum was transformed with the catalase-peroxidase gene under the control of a tRNA promoter. This bifunctional enzyme in Hbt. salinarum was not induced by environmental stresses such as H2O2, intense light, darkness, high temperature, low temperature, redox inhibitors, heavy metals, or ions.
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PMID:Archaeal promoter-directed expression of the Halobacterium salinarum catalase-peroxidase gene. 1113 77