tDisulfide bonds are among the most important factors related to correct folding of the proteins. Pro-tein disulfide isomerase (PDI) is the enzyme responsible for the correct formation and isomerization ofthese bonds. It is rarely studied so far and none of them showed industrial properties. In this study, thegene encoding for a putative PDI from Bacillus subtilis DR8806 was identified, cloned and expressed inEscherichia coli. It was encoded a 23.26 kDa protein. The enzyme was purified by GST affinity chromatog-raphy with a specific activity of 1227 u/mg. It was active and stable over a wide range of temperature(20–85◦C) and pH (4.5–10) with an optimum at 65◦C and pH 5.5. Its activity was enhanced by Mn2+and Co2+while Ag+and Zn2+decreased it. Some of the known PDI inhibitors such as Tocinoic acid andBactiracin did not affect its activity. In-silico analysis shows the five amino acids changes in the proteinsequence regarding to the consensus sequence of PDIs, have a positive impact toward the protein ther-mal stability. This was further confirmed by molecular dynamics simulations. By considering the overallresults, the enzyme might be a potential candidate for applications in the respective industries

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