The thioredoxin (Trx) system of Mycobacterium leprae is expressed as a single hybrid protein containing thioredoxin reductase (TR) at its N terminus and Trx at its C terminus. This hybrid Trx system is unique to M. leprae, since in all other organisms studied to date, including other mycobacteria, both TR and Trx are expressed as two separate proteins. Because Trx has been shown to scavenge rea...

We investigated the expression of thioredoxin (Trx) and thioredoxin reductase (TrxR) in 89 non-small cell lung carcinomas. Additionally, immortalized human bronchial epithelial cells (BEAS 2B) and four human lung carcinoma cells lines (A549, SK-MES-1, CALU-6, and A427) were studied by Western blot and reverse transcription-PCR for the synthesis of Trx and TrxR protein and mRNA expression in vit...

The 2.2 A crystalline structure of an oxidized active-site variant of Escherichia coli thioredoxin (Trx) has been solved. Trx is a 12 kDa enzyme which catalyzes the oxidation of dithiols and the reduction and isomerization of disulfides in other proteins. Its active site contains the common structural motif CXXC. Protein-disulfide isomerase (PDI), a 57 kDa homolog of Trx, contains four Trx-like...

Forty years ago, ferredoxin (Fdx) was shown to activate fructose 1,6-bisphosphatase in illuminated chloroplast preparations, thereby laying the foundation for the field now known as "redox biology." Enzyme activation was later shown to require the ubiquitous protein thioredoxin (Trx), reduced photosynthetically by Fdx via an enzyme then unknown-ferredoxin:thioredoxin reductase (FTR). These prot...

Cysteine residues in cytosolic proteins are maintained in their reduced state, but can undergo oxidation owing to posttranslational modification during redox signaling or under conditions of oxidative stress. In large part, the reduction of oxidized protein cysteines is mediated by a small 12-kDa thiol oxidoreductase, thioredoxin (Trx). Trx provides reducing equivalents for central metabolic en...

Thioredoxin (Trx) reduces disulfide bonds and play numerous important functions in plants. In cereal seeds, cytosolic h-type Trx facilitates the release of energy reserves during the germination process and is recycled by NADPH-dependent Trx reductase. This review presents a summary of the research conducted during the last 10 years to elucidate the structure and function of the barley seed Trx...

All organisms contain thioredoxin (TRX), a regulatory thiol:disulfide protein that reduces disulfide bonds in target proteins. Unlike animals and yeast, plants contain numerous TRXs for which no function has been assigned in vivo. Recent in vitro proteomic approaches have opened the way to the identification of >100 TRX putative targets, but of which none of the numerous plant TRXs can be speci...

the use of organophosphorus hydrolase (oph) enzyme to degrade chemical warfare agents is one of the most frequently used decontamination methods. oph is a ~36 kda homodimeric metalloprotein that is found in the membrane of flavobacterium sp. strain atcc 27551 and brevundimonas diminuta mg and is capable of hydrolyzing a wide range of oxon and thion , such as paraoxon and parathion. oph gene ( o...

Thioredoxin (Trx) is a cytosolic, redox-active protein that is secreted from many cells and has several extracellular functions. In activated lymphocytes, the pathway of secretion does not involve the Golgi apparatus. Levels of extracellular Trx are decreased by the antioxidant N-acetylcysteine. Hence, the secretion of Trx could be altered by the redox status of the cell or the protein. To stud...

Plants contain several genes encoding thioredoxins (Trxs), small proteins involved in the regulation of the activity of many enzymes through dithiol-disulfide exchange. In addition to chloroplastic and cytoplasmic Trx systems, plant mitochondria contain a reduced nicotinamide adenine dinucleotide phosphate-dependent Trx reductase and a specific Trx o, and to date, there have been no reports of ...