Pictorial representation of the four gene expression comparisons. The top half of the graph shows the strain comparison and the bottom half shows the hydrolysate media comparison. Heavy black arrows indicate the direction of comparison for transcriptomic analysis. Length of the arrow is used to indicate number of differentially expressed genes. The condition at the base of the arrow was used as the baseline of the comparison. Thin black arrows point to boxes that list the number of statistically significant up- or-down regulated genes and the categories with significant changes in expression in that direction.