Surface display of a bifunctional glutathione synthetase on Saccharomyces cerevisiae for converting chicken feather hydrolysate into glutathione.

The low economic profits of feather recycling lead that the large amount of feathers is currently discarded in China. To convert feather hydrolysates into GSH with high values, surface display of the bifunctional glutathione synthetase encoded by gcsgs from Streptococcus thermophilus on Saccharomyces cerevisiae and the potential in glutathione (GSH) production from feather hydrolysates were studied. The surface-displayed GCSGS could be used to convert feather hydrolysates into GSH. Results showed that 10 g/l of feather was converted into 321.8 mg/l GSH by the Trichoderma atroviride F6 and surface-displayed GCSGS in the study. Compared with production of intracellular GSH by S. cerevisiae from amino acids or feather hydrolysate, the concentration of GSH in the study was higher, and purification of GSH was more feasible. Due to the glycolytic pathway, the S. cerevisiae was used to generate ATP and cheap feather hydrolysate as precursors, the process for GSH production based on surface-displayed GCSGS is cheap and feasible. The process showed the potential to convert feather hydrolysates into GSH on an industrial scale.