Truncation of CYR1 promoter in industrial ethanol yeasts for improved ethanol yield in high temperature condition

The CYR1 promoter was serially truncated from the 3′end by 30 bp steps to finely modulating the activity of Adenylate cyclase, encoded by CYR1 and synthesizing cAMP from ATP. The constructed mutants AY15a-90 and AY15a-120, whose promoters carry 90- and 120-bp truncations, showed a 2- and 3-fold drop in adenylate cyclase activity, and improved heat and ethanol tolerances than AY15a.