Proteomics gives insight into the regulatory function of chloroplast thioredoxins.

Thioredoxins are small multifunctional redox active proteins widely if not universally distributed among living organisms. In chloroplasts, two types of thioredoxins (f and m) coexist and play central roles in regulating enzyme activity. Reduction of thioredoxins in chloroplasts is catalyzed by an iron-sulfur disulfide enzyme, ferredoxin-thioredoxin reductase, that receives photosynthetic electrons from ferredoxin, thereby providing a link between light and enzyme activity.

The atopic dog as a model of peanut and tree nut food allergy.

Background: Animal models are needed that mimic human IgE-mediated peanut and tree nut allergy. Atopic dogs have been previously used in a model of food allergy to cow's milk, beef, wheat, and soy, with the demonstration of specific IgE production and positive oral challenges similar to those seen in human subjects.

Objective: We sought to sensitize dogs to peanut, walnut, and Brazil nut and to assess whether sensitization is accompanied by clinical reactions and whether there is cross-reactivity among the different preparations.

Thioredoxin-(dithiol-)linked inactivation of elastase.

Following inactivation by the alpha-1-antitrypsin (AAT) inhibitor, the protease elastase was reduced by thioredoxin, itself reduced by NADPH and NADP-thioredoxin reductase (NTR). Under these conditions, reduction of enzyme disulfide groups was accompanied by loss of more than 60% of the activity measured following dissociation of the enzyme-inhibitor complex with NaCl. The inhibitor was required (1) to prevent proteolysis of both reduced thioredoxin and NTR and (2) to assess the progress of the reduction reaction.