The transformation efficiency with Cs+ or Li+ was comparable with that of conventional protoplast methods for a plasmid containing ars1, although not for plasmids containing a 2 microns origin replication.
The results suggest that catalase is not essential for yeast cells under normal conditions, but plays an important role in the acquisition of tolerance to oxidative stress in the adaptive response of these cells.
Three glutathione peroxidase homologs (GPX1, GPX2, and GPX3) were found in the Saccharomyces Genome Database, and the function of each gene product was investigated.
The transformation efficiency with Cs+ or Li+ was comparable with that of conventional protoplast methods for a plasmid containing ars1, although not for plasmids containing a 2 microns origin replication.
Results indicate that incompleteness of glutathione recycling alone is not sufficient to account for the increased sensitivity and inability to induce adaptation to H2O2 stress of G6PDH-deficient yeast cells.
Glutathione S-transferase was purified approximately 2,300-fold from cell extracts of Escherichia coli B with a 7.5% activity yield and appeared to consist of two homogeneous subunits.
The nucleotide sequence of the gsh I gene for gamma-glutamylcysteine synthetase(GSH I) of Escherichia coli B has been determined and the terminator signal shows the favored stem-loop structure with an adequate free energy delta G = -22.80 kcal/mol.
The effect on GSH production in the bioreactor system, containing an ATP regenerating system, of using cells containing various hybrid plasmids has now been explored and the highest glutathione-producing activity was found in the case of the cells transformed with pGS500 carrying both genes for GSH-I and G SH-II on the vector plasmid pBR325.