The shift of industrial biotechnology from highly refined sugar
syrups to more sustainable and cheaper carbon and energy
sources, such as lignocellulosic hydrolysates, also represents a shift
from single-sugar to mixed-substrate utilization (19, 39). Many
traditional applications of the yeast Saccharomyces cerevisiae are
already based on substrate mixtures, such as mixtures of glucose
and fructose in grape must and mixtures of maltose, sucrose, glucose,
and fructose in beer wort. Typically, the yeast will first consume
its preferred substrate, glucose or fructose, by the glucose
repression of genes involved in uptake and the consumption of
other substrates. This results in the sequential consumption of
multiple substrates, also known as diauxic growth