TRX activity is assayed by measuring the change in absorbance at 650 nm at 25°C using 0.13µM bovine insulin containing 0.33mM DTT (pH 6.5). The specific activity was found to be 5.8units/mg. Thioredoxin Yeast Recombinant produced in E.Coli is a single, non-glycosylated, polypeptide chain having a molecular mass of 12.6kDa. Each mg of protein contains 20mM phosphate buffer pH 7.4.TRX activity is assayed by measuring the change in absorbance at 650 nm at 25°C using 0.13µM bovine insulin containing 0.33mM DTT (pH 6.5). The specific activity was found to be 5.8units/mg.