CYSH E.Coli

The recombinant form of this enzyme, derived from Escherichia coli (E. coli), is a single, non-glycosylated polypeptide chain containing 264 amino acids. It has a molecular mass of approximately 30.1 kDa. The recombinant enzyme is often fused to a 20 amino acid His-tag at the N-terminus to facilitate purification .

PAPS reductase catalyzes the reduction of PAPS to sulfite and adenosine 3’,5’-bisphosphate. This reaction is essential for the biosynthesis of cysteine and other sulfur-containing compounds in bacteria. The enzyme uses thioredoxin as a cofactor, which is oxidized during the reaction. The overall reaction can be summarized as follows:

$$\text{PAPS} + \text{Thioredoxin (reduced)} \rightarrow \text{Adenosine 3',5'-bisphosphate} + \text{Sulfite} + \text{Thioredoxin (oxidized)}$$

Recombinant PAPS reductase from E. coli is widely used in research to study the sulfate assimilation pathway and its regulation. It is also utilized in the production of sulfated polysaccharides and other sulfated biomolecules. The enzyme’s ability to catalyze the reduction of PAPS makes it a valuable tool in biochemical and biotechnological applications .

The recombinant enzyme is typically supplied in a solution containing 20 mM Tris-HCl buffer (pH 8.0), 1 mM DTT, 10% glycerol, and 50 mM NaCl. It is shipped with ice packs and should be stored at -20 to -70°C to maintain its stability. It is important to avoid repeated freeze-thaw cycles to preserve the enzyme’s activity .