Sulfur containing secondary metabolites are prime modulators of  the redox and metal homeostasis in microbial as well as human cells and therefore play important roles in many medical disorders. The identification of novel biothiols and investigation of their biosynthesis physiological functions has gained much interest in the last few years.^3-6. The enzymology of sulfur incorporation for many of these compounds is not clear and suggesting that much of C-S bond forming biocatalysis is yet to be discovered.