Fuel ethanol production using renewable cellulosic materials has attracted widespread attention by researchers. However

acetic acid released from the pretreatment process exerts severe inhibition on yeast cell growth and ethanol fermentation. Therefore

improvement of acid tolerance of industrial Saccharomyces cerevisiae benefits efficient cellulosic ethanol production. In this work

glutaredoxin encoding gene GRX5 was overexpressed in S. cerevisiae

and it was found that the GRX5 overexpression strain grew better than that of the control strain in the plates containing 5 g·L-1 acetic acid. When ethanol fermentation in the presence of 5 g·L-1 acetic acid was evaluated

it was found that the GRX5 overexpression strain consumed all glucose in the broth within 48 h

12 h shorter than that of the control strain. Ethanol productivity of the GRX5 overexpressed strain was determined to be 0.897 g·L-1·h-1

with a 28.5% increase than that of the control strain. Analysis of the key metabolites showed that the GRX5 overexpression strain produced higher concentration of trehalose and glycerol

which might explain its improved cell viability in the presence of acetic acid stress.