# Comparative Proteomics of Two Flor Yeasts in Sparkling Wine Fermentation: First Approach
## 3 Results
### Protein Clustering Analysis
#### 3.4.3. Differential Expression Analysis: ANOVA and HSD Tukey Test  
Finally, out of a total of 574 proteins, 127 proteins exceeded the statistical threshold and showed statistical differences in quantification values according to the one-way ANOVA and HSD Tukey tests in comparisons between G1 and N62, with a \(q\)-value \(<0.05\). After statistical screening, 63 proteins with significant upward differences were obtained for  
Figure 5: (**a**) Bubble plot and (**b**) protein–protein interaction network map of the N62 strain-specific proteins. strain N62, and 64 proteins with significant upward differences were obtained for strain G1, as shown in Figure 6a. These proteins were subjected to another ANOVA and Tukey test, but with a \(q\)-value < 0.01 and an FC > 2. This resulted in 51 proteins showing a greater quantitative difference. These are shown in a radar plot in Figure 6b. Of these 51 proteins with high significant differences, 29 proteins showed maximum quantification peaks in strain N62, and 22 proteins presented maximum quantification values in strain G1. Of the 29 proteins from N62, three are part of cluster 5, and their molecular functions include hydrolase activity, while MAP1 belongs to the peptidase family; for RNA binding, RPS15, both proteins interact with each other as shown in INM5, and the latter is part of the ribosome structure; in the binding of RNAAm, PAB1 has an RNA binding function, as observed in INMS5, involved in the control of the length of the poly(A) tail. The rest of the proteins with maximum quantification peaks in strain N62 belong to cluster 2, and their molecular functions include lyase activity; one of them is a glyoxalase HSP31, involved in resistance to oxidative stress, and the others are located in the mitochondria. They also interacted with the rest of the proteins of the same cluster, as observed in INM2; oxidoreductase activity, GLR1, has a role in hyperoxia resistance, OYE3 modulates oxidative stress-induced programmed cell death in yeast, and MAE1 catalyzes the oxidative decarboxylation of malate to pyruvate, a key intermediate in sugar metabolism and a precursor for the synthesis of several amino acids. This protein interacts with MDH3; as observed in INM2, it is involved in the glyoxylate cycle and catalyzes the interconversion of malate and oxaloacetate, and CTT1 is a catalase that is responsible for the degradation of hydrogen peroxide, protecting yeast from oxidative stress; hydrolase activity, GPP2 is involved in glycerol biosynthesis; ATP hydrolysis activity, one of which, RPT5, is involved in the degradation of ubiquitinated substrates; SSA4 is important in the orientation and membrane translocation of co-translational proteins and also has significant interaction with several cluster 2 proteins; transferase activity, for QRI1, catalyzes the formation of UDP-N-acetylglucosamine, which is important for cell wall biosynthesis; in kinase activity, POS5 phosphorylates NADH and also interacts with the previous function; in DNA binding, HTB1 is required for chromatin assembly and chromosome function; translation elongation  
Figure 6: (**a**) Volcano plot of proteins with significant differences at \(q\)-value < 0.05. The up-regulated proteins correspond to the yellow spheres (LFC > 0) and the down-regulated proteins correspond to the green spheres (LFC < 0). Proteins without significant differences are shown in gray.