Figure 4.

CysM dependent L-cysteine production. ΔcysM or ΔcysK harboring pDES was transformed plasmids overexpressing empty vector (pCA24N), pGrx1 or pNrdH. These strains were cultivated in SM1 with 30 mM thiosulfate and 30 mM sulfate medium for 36 hours to compare amount of L-cysteine produced from ΔcysM or ΔcysK, respectively. The concentration of L-cysteine plus L-cystine was determined by Gaitonde method. Values indicate means and standard deviations of results from three independent experiments.